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Background: Hemodialysis patients are at high risk for developing Pneumocystis jirovecii pneumonia (PJP), and trimethoprim–sulfamethoxazole (TMP–SMX) is the first-line agent for treating this disease. However, there is a lack of consensus on the required dosage of TMP–SMX for hemodialysis patients. Methods: This study used the nationwide Japanese Diagnosis Procedure Combination database to review hemodialysis patients hospitalized for PJP from April 2014 to March 2022. Eligible patients were divided into high-dose and low-dose groups based on the median daily dose per body weight of TMP. The 90-day mortality and adverse events after propensity score matching were compared between the groups. Results: A total of 126 hemodialysis patients with PJP were included, and the median daily dose per body weight of TMP was 5.74 mg/kg/day (interquartile range: 4.33–8.18 mg/kg/day). Thirty-two pairs were analyzed after the propensity score matching. No significant differences in the 90-day mortality and proportion of adverse events were observed between the high-dose and low-dose groups. Conclusions: A high dose of TMP–SMX is unlikely to decrease the in-hospital mortality and adverse events among hemodialysis patients with PJP. However, the results should be interpreted with caution, given the lack of power and lack of long-term follow-up. Additional prospective interventional studies are required to validate these results. [ABSTRACT FROM AUTHOR]

Objective: Analyze the duration of symptom‐free intervals following laser wedge excision (LWE) for recurrent idiopathic subglottic stenosis (iSGS). Secondary aim includes evaluating the influence of patient‐related or disease factors. Study Design: Retrospective review. Setting: Tertiary center. Methods: Review of iSGS patients who underwent LWE between 2002 and 2021. LWE patients without prior airway surgery were labeled LWE primary (LWEP) and those with prior history of dilation were labeled LWE secondary (LWES). A conditional frailty repeated events model was used to analyze the median time to recurrence (MTR) for each nth recurrence. Secondary analysis included stratification by use of medical therapy and initial preoperative characteristics of scar (Myer‐Cotton grade, distance between the glottis and superior‐most aspect of scar, DGS; length of scar, DL). Results: Two hundred and ten iSGS patients underwent LWE (131 LWEP, 79 LWES). The proportion of patients experiencing at least 1, 3, 6, and 12 recurrences, respectively, was 68.0% (n = 143), 40.7% (n = 85), 20.0% (n = 42), and 5.2% (n = 11). There was exponential time‐shortening from the 1st to 12th recurrence (P <.0001). While MTR was 4.1 years after the first LWE, this fell to 2.8, 1.7, 1.0, and 0.7 years for the 2nd, 3rd, 6th, and 12th recurrences. Furthermore, LWEP patients experienced longer MTR than LWES counterparts within the first 6 recurrences (P <.01). There was no significant relationship between intersurgical interval and medication adherence, DL, DGS, or grade for recurrences beyond the first (P =.207, P =.20, P =.43, P =.16). Conclusion: Symptom‐free intervals in iSGS shorten with each subsequent recurrence and LWE. The difference in MTR between LWEP and LWES groups was significant within the first 6 recurrences with LWEP having longer MTR. Level of Evidence: 3. [ABSTRACT FROM AUTHOR]

Qimei Wei,1,&ast; Wenxia Zuo,2,&ast; Rong Cong,1 Kun Luo,1 Shanshan Dong1 1Department of Clinical Laboratory, Wuhan Asia Heart Hospital, Wuhan, 430022, People’s Republic of China; 2Department of Cardiac Critical Care Medicine, Wuhan Asia Heart Hospital, Wuhan, 430022, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Shanshan Dong, Department of Clinical Laboratory, Wuhan Asia Heart Hospital, No. 753 Jinghan Avenue, Jianghan District, Wuhan, 430022, People’s Republic of China, Tel +86 18162516279, Email 18162516279@163.comAbstract: Elizabethkingia anophelis is an opportunistic pathogen that causes serious life-threatening infections. In this report, we describe a case of pulmonary infection caused by E. anophelis in a young female patient, following cardiac surgery, which was successfully treated with a combination of trimethoprim-sulfamethoxazole (TMP-SMZ) and eravacycline. Additionally, this report provides a summary of high-risk factors for E. anophelis infection, clinical manifestations, and therapeutic options. Given the high degree of antimicrobial drug resistance of the organism and the fact that inappropriate empirical antimicrobial therapy constitutes a risk factor for mortality, our case serves as a valuable reference for similar cases, highlighting potential strategies for effective management.Keywords: Elizabethkingia anophelis, pulmonary infections, trimethoprim-sulfamethoxazole, eravacycline

Background: Trimethoprim-sulfamethoxazole (TMP-SMX) has long been considered the treatment of choice for infections caused by Stenotrophomonas maltophilia. Levofloxacin has emerged as a potential option for treating these infections. This study aimed to evaluate the clinical outcomes in patients who received TMP-SMX versus levofloxacin for treating S. maltophilia infections. Methods: A retrospective, cohort study was conducted in 4 tertiary centres and included patients who were treated with either TMP-SMX or levofloxacin for infections caused by S. maltophilia. The main study outcomes were overall in-hospital mortality, 30-d mortality, and clinical cure. Safety outcomes were also evaluated. Multivariate analysis using logistic regression was used to control for the effect of the covariables. Results: We included 371 patients in this study, 316 received TMP-SMX and 55 patients received levofloxacin. A total of 70% were in the intensive care unit and 21% presented with bacteraemia. No statistically significant differences were observed in overall in-hospital mortality (52% vs. 40%; P = 0.113; odd ratio [OR], 1.59; 95% confidence interval [CI], 0.89–2.86), 30-d mortality (28% vs. 25%; P = 0.712; OR, 1.13; 95% CI, 0.59–2.18), or clinical cure (55% vs. 64%; P = 0.237; OR, 0.70; 95% CI, 0.37–1.31). Rates of acute kidney injury were comparable between the two groups (11% vs. 7%; P = 0.413). Conclusion: Patients receiving levofloxacin for the treatment of infections caused by S. maltophilia demonstrated clinical outcomes similar to those receiving TMP-SMX. Our study suggests that levofloxacin can be a reasonable alternative to TMP-SMX to treat these infections.

Nocardiosis in patients after allogeneic hematopoietic stem cell transplantation (HSCT) is rare, but is associated with a significant mortality risk. Although trimethoprim-sulfamethoxazole (TMP/SMX) remains the cornerstone of nocardiosis treatment, optimal alternative therapies for patients intolerant to TMP/SMX are not well-established. Herein, we report a case of disseminated nocardiosis with bacteremia and multiple lesions in the lungs and brain caused by Nocardia farcinica , in a 60-year-old man who had previously undergone allogeneic HSCT and was receiving immunosuppressants for severe chronic graft-versus-host disease. The patient received atovaquone for the prophylaxis of Pneumocystis pneumonia because of a previous serious allergic reaction to TMP/SMX. The patient was initially treated with imipenem/cilastatin and amikacin, which were later switched to ceftriaxone and amikacin based on the results of antimicrobial susceptibility testing. After switching to oral levofloxacin and a standard dose of minocycline, the patient experienced a single recurrence of brain abscesses. However, after switching to oral moxifloxacin and high-dose minocycline, the patient did not experience any relapses during the subsequent two years and seven months of treatment. In treating nocardiosis with brain abscesses, it is crucial to select oral antibiotics based on the antimicrobial susceptibility test results and pharmacokinetics, especially when TMP/SMX is contraindicated. A combination of oral moxifloxacin and high-dose minocycline could be a promising alternative therapy. [ABSTRACT FROM AUTHOR]

We present a case of a young male from a low socioeconomic background who presented with mucosal ulceration, hematemesis episodes, and pancytopenia following treatment with trimethoprim-sulfamethoxazole (TMP-SMX) for a urinary tract infection. On examination, the patient exhibited signs of severe anemia and hemodynamic instability. After stabilization and a thorough workup a diagnosis of idiosyncratic drug reaction secondary to TMP-SMX was established, believed to be exacerbated by the patient’s immune-hyperactive state due to a recent HIV diagnosis. Initiation of methylprednisolone therapy resulted in rapid improvement in blood parameters. This case highlights the complexity of TMP-SMX-induced pancytopenia in the context of HIV infection and emphasizes the prompt recognition and management of such life-threatening adverse reactions in immunocompromised individuals.

Background. The outcome of complex treatment of implant-associated infection (IAI) depends on various factors, but one of the most important is the etiology of the inflammatory process. Treatment of orthopedic infection caused by Gram-negative microorganisms in general and representatives of the family Enterobacteriaceae in particular causes many difficulties, one of which is the rapid growth of antibiotic resistance. Aim of the study — to evaluate the factors affecting the course and prognosis of implant-associated infection caused by Klebsiella spp. Methods. We performed a retrospective analysis of case histories of 85 patients who underwent treatment of IAI caused by Klebsiella spp. in the clinical departments of the center from January 1, 2017 to December 31, 2021. According to the results of the telephone survey, the patients were divided into 2 main groups depending on the outcome of the 2-year follow-up period determined in accordance with the Delphi criteria. Results. It was found that the prognosis was significantly worsened by the number of sanitizing surgical interventions in the anamnesis (p = 0.022), the need for sanitizing intervention in the early postoperative period (p0.001) and the presence of Klebsiella spp. growth in postoperative culture tests (p = 0.002), hypoalbuminemia on 7-14 days after the surgery (p = 0.008). The administration of trimethoprim-sulfamethoxazole for the outpatient treament stage significantly improved the outcome (p = 0.038), which is most likely due to a high proportion of polymicrobial associations — 69.5%. Conclusions. There is a statistically significant direct relationship between the probability of an unfavorable treatment outcome of patients with IAI caused by Klebsiella spp. and the number of sanitizing surgical interventions in the anamnesis, low serum albumin (g/l) on 7-14 days after the operation, revision intervention in the early postoperative period, positive growth of Klebsiella spp. in postoperative culture tests. The probability of a favorable outcome was increased by the prescription of trimethoprim-sulfamethoxazole for oral administration at the outpatient stage.

Wenya Shan,1– 3 Liangping Wang,1,4 Jiayi Qin,1– 3 Wenhan Peng,5 Kuifen Ma1– 3 1Department of Clinical Pharmacy, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, People’s Republic of China; 2Zhejiang Provincial Key Laboratory for Drug Evaluation and Clinical Research, Hangzhou, People’s Republic of China; 3Zhejiang Provincial Key Laboratory of Traditional Chinese Medicine for Clinical Evaluation and Translational Research, Hangzhou, People’s Republic of China; 4Department of Pharmacy, Hangzhou Linping District Hospital of Integrated Chinese and Western Medicine, Hangzhou, People’s Republic of China; 5Kidney Disease Center, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, People’s Republic of ChinaCorrespondence: Wenhan Peng, Kidney Disease Center, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, People’s Republic of China, Tel +8687233411, Email 1198027@zju.edu.cn Kuifen Ma, Department of Clinical Pharmacy, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, People’s Republic of China, Email makuifen@zju.edu.cnBackground: The administration of trimethoprim-sulfamethoxazole (TMP-SMX) for the prophylaxis of Pneumocystis jirovecii pneumonia (PJP) has proven to be highly efficacious in individuals who have undergone kidney transplantation. Nevertheless, the potential for severe adverse reactions associated with this treatment cannot be overlooked, and the determination of an optimal dosage regimen continues to be a matter of investigation. The current study evaluated the effectiveness of low-dose TMP-SMX for PJP prophylaxis in kidney transplant patients and conducted an analysis of the clinical characteristics and epidemiological trends in patients with PJP infection.Methods: This retrospective analysis studied electronic medical records of 1763 kidney transplant recipients from 2017 to 2020. These patients were initially prescribed a daily half-strength TMP-SMX (40 mg/200 mg), and the efficacy of this regimen was assessed during a follow-up period of 3– 51 months.Results: Under our PJP prevention and adjustment strategy, 24 patients were infected with PJP. The overall morbidity of PJP infection in our study was 1.36%, corroborates with findings from previously published studies. Among these 24 patients, up to 87.5% had their dosage adjusted due to increased creatinine or other adverse reactions, the most frequent dose was daily quarter-strength TMP-SMX (20 mg/100 mg). TMP-SMX prophylaxis successfully postponed and distributed the onset of PJP, with the mean duration from transplantation to the occurrence of PJP being 13.50± 7.11 months.Conclusion: Daily administration of half-strength TMP-SMX can effectively prevent PJP, and prolonging prophylaxis with this medication may potentially reduce the incidence of infection.Keywords: efficacy, kidney transplant recipients, Pneumocystis jirovecii pneumonia, trimethoprim-sulfamethoxazole

Background In clinical practice, challenges in identifying patients with uncomplicated urinary tract infections (uUTIs) at risk of antibiotic nonsusceptibility may lead to inappropriate prescribing and contribute to antibiotic resistance. We developed predictive models to quantify risk of nonsusceptibility to 4 commonly prescribed antibiotic classes for uUTI, identify predictors of nonsusceptibility to each class, and construct a corresponding risk categorization framework for nonsusceptibility. Methods Eligible females aged ≥12 years with Escherichia coli– caused uUTI were identified from Optum's de-identified Electronic Health Record dataset (1 October 2015–29 February 2020). Four predictive models were developed to predict nonsusceptibility to each antibiotic class and a risk categorization framework was developed to classify patients' isolates as low, moderate, and high risk of nonsusceptibility to each antibiotic class. Results Predictive models were developed among 87 487 patients. Key predictors of having a nonsusceptible isolate to ≥3 antibiotic classes included number of previous UTI episodes, prior β-lactam nonsusceptibility, prior fluoroquinolone treatment, Census Bureau region, and race. The risk categorization framework classified 8.1%, 14.4%, 17.4%, and 6.3% of patients as having isolates at high risk of nonsusceptibility to nitrofurantoin, trimethoprim-sulfamethoxazole, β-lactams, and fluoroquinolones, respectively. Across classes, the proportion of patients categorized as having high-risk isolates was 3- to 12-fold higher among patients with nonsusceptible isolates versus susceptible isolates. Conclusions Our predictive models highlight factors that increase risk of nonsusceptibility to antibiotics for uUTIs, while the risk categorization framework contextualizes risk of nonsusceptibility to these treatments. Our findings provide valuable insight to clinicians treating uUTIs and may help inform empiric prescribing in this population. [ABSTRACT FROM AUTHOR]

Hemodialysis is a risk factor for Staphylococcus aureus bloodstream infection (SAB). In this single-center study, SAB rates were 56% lower during the monsoonal wet season when patients on hemodialysis receive supervised melioidosis prophylaxis with trimethoprim-sulfamethoxazole. This intervention may reduce SAB rates in high-risk patients; however, further targeted studies are required. [ABSTRACT FROM AUTHOR]

Infection management in solid organ transplantation poses unique challenges, with a diverse array of potential pathogens and associated antimicrobial therapies. With limited high-quality randomized clinical trials to direct optimal care, therapeutic "myths" may propagate and contribute to suboptimal or excessive antimicrobial use. We discuss 6 therapeutic myths with particular relevance to solid organ transplantation and provide recommendations for infectious diseases clinicians involved in the care of this high-risk population. [ABSTRACT FROM AUTHOR]

We present a case of a young male from a low socioeconomic background who presented with mucosal ulceration, hematemesis episodes, and pancytopenia following treatment with trimethoprim-sulfamethoxazole (TMP-SMX) for a urinary tract infection. On examination, the patient exhibited signs of severe anemia and hemodynamic instability. After stabilization and a thorough workup a diagnosis of idiosyncratic drug reaction secondary to TMP-SMX was established, believed to be exacerbated by the patient's immune-hyperactive state due to a recent HIV diagnosis. Initiation of methylprednisolone therapy resulted in rapid improvement in blood parameters. This case highlights the complexity of TMP-SMX-induced pancytopenia in the context of HIV infection and emphasizes the prompt recognition and management of such life-threatening adverse reactions in immunocompromised individuals. [ABSTRACT FROM AUTHOR]

A 77-year-old immunocompetent male agricultural worker presented with a 9-year history of hand stiffness, edema, and draining wounds. Despite two surgeries and antibiotic use many times, his condition persisted. Initially treated for a deep fungal infection with Itraconazole for 9 months without improvement, Nocardia spp. were later identified in deep tissue culture via microbiological examination by Gram-staining and isolation in culture media. He was treated with trimethoprim-sulfamethoxazole (TMP-SMX) 160/800 mg for six months, leading to regression of the cutaneous lesions. However, magnetic resonance imaging revealed osteomyelitis and tenosynovitis, prompting an extended 12-month treatment with increased doses of TMP-SMX and a month of ceftriaxone. Complete recovery was achieved after 12 months. This case highlights the rarity and diagnostic challenges of nocardiosis, emphasizing the need for thorough microbiological evaluation, extended antibiotic treatment, and imaging follow-up for persistent, deep localized infections. Primary cutaneous nocardiosis should be considered, particularly in patients with non-healing skin lesions and a history of soil exposure. [ABSTRACT FROM AUTHOR]

BackgroundThe recommended standard treatment for Pneumocystis jirovecii pneumonia (PJP) is high-dose trimethoprim-sulfamethoxazole (TMP-SMX) (15–20 mg/kg/d TMP). However, the standard regimen may cause a high incidence of dose-related adverse events (AEs). Therefore, we aimed to conduct a systematic review and meta-analysis to evaluate the efficacy and safety of low-dose TMP-SMX regimens (

Myasthenia gravis (MG) is an autoimmune disease. Patients with MG due to compromised autoimmune regulation, progressive muscle weakness, and prolonged use of immunosuppressants and glucocorticoid, often present with concomitant infections. However, cases of MG complicated by Nocardia infection are rare. In this case, we report MG complicated with pulmonary infection by Nocardia cyriacigeorgica. A 71-year-old male farmer who was admitted for management of MG. After 7 weeks of treatment of MG, the patient reported improvement. However, clinical presentation, inflammatory markers, and imaging findings supported a diagnosis of pulmonary infection. To further elucidate the etiology, Nocardia was identified in sputum smear microscopy and sputum culture, with 16S rRNA gene sequencing confirming N. cyriacigeorgica. The patient was prescribed trimethoprim-sulfamethoxazole. After 1 month of treatment, clinical symptoms of MG and pulmonary nocardiosis showed significant improvement. Additionally, we searched PubMed for case reports of Nocardia cyriacigeorgica pulmonary infection from 2010 to 2024 and conducted a statistical analysis of the case information. This report aims to highlights the increased risk of pulmonary Nocardia infection in MG patients after the use of steroids and immunosuppressants, thereby enhancing clinical awareness.

BackgroundPneumocystis jirovecii pneumonia (PJP) is an opportunistic infection caused by the yeast-like fungus P. jirovecii. As recommended by some guidelines, the first-line treatment for this infection is trimethoprim-sulfamethoxazole (TMP-SMX), and the second-line treatment includes drugs such as dapsone, pentamidine, primaquine, Atovaquone, clindamycin, and caspofungin. Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an X-linked gene disorder in which treatment with oxidizing drugs, such as sulfonamides, dapsone, primaquine, can directly destroy hemoglobin present in red blood cells (RBCs), thereby inducing methemoglobin and hemolysis.Case presentationHere, we present the case of a lymphoma patient with previous G6PD deficiency who was admitted to ICU for the treatment of severe pneumonia combined with respiratory failure. PJP was detected by the next-generation sequencing of the bronchoalveolar lavage fluid. The patient was initially treated with the antifungal drug caspofungin; however, this treatment showed poor therapeutic effect. Based on the evaluation of G6PD enzyme activity and the patient’s previous history of G6PD deficiency, we finally treated the patient with low-dose TMP-SMX combined with caspofungin and provided rigorous medical care to the patient. Following this treatment, the patient’s clinical symptoms improved, lung computed tomography showed reduced pulmonary inflammation, and the fungal β-(1,3)-D-glucan test (G test) showed decreased levels of fungal D-glucan. After 57 days, the TMP-SMX treatment was discontinued. No symptoms related to G6PD deficiency, such as hemolysis, hematuria, and anemia, occurred during the treatment course.ConclusionThis is the first report mentioning the successful treatment of Pneumocystis jirovecii pneumonia with a double-drug regimen with low-dose TMP-SMX and caspofungin in a T-lymphoblastic leukemia/lymphoma patient with previous G6PD deficiency. Enzyme activity detection is the first step for anti-PJP treatment in patients with G6PD deficiency. Although patients with mild enzyme deficiency may not show any adverse reactions, we still recommend the regular monitoring of the levels of RBCs, hemoglobin, and hematocrit before and after the use of sulfonamides or sulfoxides and other oxidizing drugs in patients with G6PD deficiency. Among other things, early and correct diagnosis of Pneumocystis jirovecii pneumonia in hematological malignancies patients is very important. Relevant oncologists should be alert to the risk of Pneumocystis jirovecii pneumonia in these patients.

Nocardia is a genus of aerobic, Gram-positive bacteria known for their filamentous and branching morphology. N. brasiliensis is the most common species causing cutaneous nocardiosis. We present a 67-year-old woman who developed abscesseson the back of her right ankle after walking barefoot on soil. Cultures from the cutaneous lesions grew N. brasiliensis. Antibiotic therapy with trimethoprim-sulfamethoxazole given for a month provided near-complete resolution of her lesions. [ABSTRACT FROM AUTHOR]

Huaichong Wang,1 Yuying Lang,1 Xinjun Cai,1 Liujie Gao,2 Shengya Yang,3 Jie Jin1 1Department of Pharmacy, Hangzhou Red Cross Hospital, Hangzhou, Zhejiang Province, People’s Republic of China; 2Department of Oncology, Hangzhou Red Cross Hospital, Hangzhou, Zhejiang Province, People’s Republic of China; 3Tuberculosis Diagnosis and Treatment Center, Hangzhou Red Cross Hospital, Hangzhou, Zhejiang Province, People’s Republic of ChinaCorrespondence: Jie Jin, Department of Pharmacy, Hangzhou Red Cross Hospital, East Huancheng Road No. 208, Hangzhou, Zhejiang Province, People’s Republic of China, Email jinjie0916@163.comBackground: Lymphoma is complicated by intricate infections, notably Pneumocystis jirovecii pneumonia (PJP), marked by rapid progression, respiratory failure, and high mortality. Rapid diagnosis of PJP and effective administration of the first-line treatment trimethoprim-sulfamethoxazole (TMP-SMX) are important. For patients intolerant to TMP-SMX, selecting appropriate alternatives is challenging, necessitating careful decisions to optimize diagnosis and treatment. We present a lymphoma case complicated by PJP, illustrating medication adjustment until a positive response was observed.Case Description: A 41-year-old male patient with lymphoma presented with a week-long history of fever, fatigue, cough, sputum, chest tightness, and exertional dyspnea, unresponsive to treatment. Routine laboratory examinations revealed no pathogenic bacteria. PJ and Mycobacterium tuberculosis (MTB) were detected in bronchoalveolar lavage fluid (BALF) using metagenomic next-generation sequencing (mNGS). On Day 1 of admission, meropenem, TMP-SMX, and rifampicin+isoniazid+levofloxacin were administered. However, the patient developed drug-induced hepatotoxicity and gastrointestinal adverse reactions after six days of treatment. After a multidisciplinary team discussion, anti-tuberculosis therapy was stopped because of insufficient evidence of tuberculosis infection. A reduced dose of TMP-SMX with micafungin was used for PJP; however, symptoms persisted and repeated computed tomography showed extensive deterioration of bilateral pulmonary plaques. The PJP regimen was modified to include a combination of TMP-SMX and caspofungin. Due to the high fever and elevated infection indices, the patient was treated with teicoplanin to enhance the anti-infection effects. By Day 13, the patient’s temperature had normalized, and infection control was achieved by Day 30. CT revealed that the infection in both lung lobes fully resolved. Subsequently, lymphoma treatment commenced.Conclusion: BALF-NGS facilitates early and rapid diagnosis of PJP. mNGS reads of MTB bacillus < 5 may indicate a bacterial carrier state, warranting other detection techniques to support it. There is insufficient evidence for using TMP-SMX with micafungin to treat PJP; however, TMP-SMX combined with caspofungin is suitable.Keywords: bronchoalveolar lavage fluid, metagenomic next-generation sequencing, Pneumocystis jirovecii pneumonia, Mycobacterium tuberculosis, trimethoprim-sulfamethoxazole

Objective: Stenotrophomonas maltophilia is an emerging multi-drug resistant, opportunistic pathogen in the neonatal intensive care unit (NICU). In this study, we aimed to assess the incidence, clinical features, antibiotic susceptibility, and treatment options of S. maltophilia infection among the healthcare-associated infections (HAIs) in the neonatal unit. Methods: In this study, the patients who were hospitalized in the NICU between January 2020 and December 2021 with S. maltophilia isolated from clinical samples were included. Demographic, clinic features, and microbiological findings of the patients were retrospectively evaluated by using the medical records. The samples (lower respiratory tract, urine, peritoneal fluid) were first examined microscopically by gram preparation and cultured. Antibiotic susceptibility tests were performed according to the recommendations of The European Committee on Antimicrobial Susceptibility Testing (EUCAST) for TMP-SMX. Results: S. maltophilia was isolated in 38 clinical samples of the 20 patients who were hospitalized at the NICU between January 2020 and December 2021. A total of 40 % (n = 8) of samples from different patients were accepted as colonization. Ventilator-associated pneumonia was determined in 55 % (n = 11), and urinary tract infection in 5 % (n = 1). S. maltophilia-associated bacteremia was not detected in any of the cases. The TMP-SMX susceptibilities of the strains were as it follows: 3 (15 %) were resistant (R), 7 (28 %) were susceptible (S), and 10 (47 %) were susceptible-increased exposure (I). Three of these patients were given dual antibiotics therapy (levofloxacin plus TMP-SMX) and nine of them were given only TMP-SMX. The most common hospital-acquired infectious agents are Gram negative microorganisms (51 %), followed by coagulase negative staphylococci (CNS), Staphylococcus aureus (24 %) and S. maltophilia (24 %). Conclusion: Increasing TMP-SMX resistance and specific drug and dosage-related problems in the neonatal unit are important problems in treatment management.

Background Nocardia tends to cause infection in immunocompromised patients or those with chronic pulmonary disease. Nocardia is known to recur, prompting the practice of secondary prophylaxis in patients perceived at high risk. However, few data exist regarding the epidemiology of recurrent nocardiosis or the effectiveness of secondary prophylaxis. Methods We performed a multicenter, retrospective cohort study of adults diagnosed with nocardiosis from November 2011 to April 2022, including patients who completed primary treatment and had at least 30 days of posttreatment follow-up. Propensity score matching was used to analyze the effect of secondary prophylaxis on Nocardia recurrence. Results Fifteen of 303 (5.0%) patients developed recurrent nocardiosis after primary treatment. Most recurrences were diagnosed either within 60 days (N = 6/15, 40.0%) or between 2 to 3 years (N = 4/15, 26.7%). Patients with primary disseminated infection tended to recur within 1 year, whereas later recurrences were often nondisseminated pulmonary infection. Seventy-eight (25.7%) patients were prescribed secondary prophylaxis, mostly trimethoprim-sulfamethoxazole (N = 67/78). After propensity-matching, secondary prophylaxis was not associated with reduced risk of recurrence (hazard ratio, 0.96; 95% confidence interval,.24–3.83), including in multiple subgroups. Eight (53.3%) patients with recurrent nocardiosis required hospitalization and no patients died from recurrent infection. Conclusions Recurrent nocardiosis tends to occur either within months because of the same Nocardia species or after several years with a new species. Although we did not find evidence for the effectiveness of secondary prophylaxis, the confidence intervals were wide. However, outcomes of recurrent nocardiosis are generally favorable and may not justify long-term antibiotic prophylaxis for this indication alone. [ABSTRACT FROM AUTHOR]

• Whipple's disease is a very rare, multisystemic, chronic infection due to Tropheryma whipplei , an actinobacterium found in soil. • Diagnosis is challenging due to both its rarity and non-specific clinical features resembling rheumatological conditions. • A few years later, gastrointestinal symptoms appear helping to reach the correct diagnosis. Fatal central nervous system involvement can occur. • Diagnosis is based on PAS-positive macrophages in the duodenal lamina propria and positive PCR for Tropheryma whipplei in affected tissues.. • Treatment has not yet been fully established, particularly in cases of recurrent disease Whipple's disease, an extremely rare, chronic infection caused by Tropheryma whipplei , an actinobacterium ubiquitously present in the environment, is a multisystemic condition that can affect several organs. Therefore, Whipple's disease should always be considered by physicians working across various branches of medicine, including internal medicine, rheumatology, infectious diseases, gastroenterology, haematology, and neurology. Initially, Whipple's disease is challenging to diagnose due to both its rarity and non-specific clinical features, almost indistinguishable from rheumatological conditions. A few years later, the onset of gastrointestinal symptoms increases the specificity of its clinical picture and helps in reaching the correct diagnosis. Diagnosis is typically made by finding PAS-positive macrophages in the lamina propria at duodenal biopsy. PCR for Tropheryma whipplei is nowadays also increasingly available, and represents an undeniable help in diagnosing this condition. However, it may also be misleading as false positives can occur. If not promptly recognized and treated, central nervous system involvement may develop, which can be fatal. The therapeutic gold standard has not yet been fully established, particularly in cases of recurrent disease, neurological involvement, and an immune reconstitution inflammatory syndrome that may arise following the initiation of antibiotic therapy. [ABSTRACT FROM AUTHOR]

Stenotrophomonas maltophilia is an emerging multi-drug resistant, opportunistic pathogen in the neonatal intensive care unit (NICU). In this study, we aimed to assess the incidence, clinical features, antibiotic susceptibility, and treatment options of S. maltophilia infection among the healthcare-associated infections (HAIs) in the neonatal unit. In this study , the patients who were hospitalized in the NICU between January 2020 and December 2021 with S. maltophilia isolated from clinical samples were included. Demographic, clinic features, and microbiological findings of the patients were retrospectively evaluated by using the medical records. The samples (lower respiratory tract, urine, peritoneal fluid) were first examined microscopically by gram preparation and cultured. Antibiotic susceptibility tests were performed according to the recommendations of The European Committee on Antimicrobial Susceptibility Testing (EUCAST) for TMP-SMX. S. maltophilia was isolated in 38 clinical samples of the 20 patients who were hospitalized at the NICU between January 2020 and December 2021. A total of 40 % (n = 8) of samples from different patients were accepted as colonization. Ventilator-associated pneumonia was determined in 55 % (n = 11), and urinary tract infection in 5 % (n = 1). S. maltophilia -associated bacteremia was not detected in any of the cases. The TMP-SMX susceptibilities of the strains were as it follows: 3 (15 %) were resistant (R), 7 (28 %) were susceptible (S), and 10 (47 %) were susceptible-increased exposure (I). Three of these patients were given dual antibiotics therapy (levofloxacin plus TMP-SMX) and nine of them were given only TMP-SMX. The most common hospital-acquired infectious agents are Gram negative microorganisms (51 %), followed by coagulase negative staphylococci (CNS), Staphylococcus aureus (24 %) and S. maltophilia (24 %). Increasing TMP-SMX resistance and specific drug and dosage-related problems in the neonatal unit are important problems in treatment management. [ABSTRACT FROM AUTHOR]

Staphylococcus aureus bacteremia (SAB) is a common and serious condition, particularly among patients on long-term hemodialysis. A study conducted in Northern Australia found that the incidence of SAB was significantly lower during the wet season when patients received trimethoprim-sulfamethoxazole (TMP-SMX) prophylaxis after hemodialysis. However, there were limitations to the study, including its retrospective design and small sample size. While TMP-SMX has a broad spectrum of activity against various infections, it also has numerous adverse effects and concerns about increasing antimicrobial resistance. Further research is needed to determine the risks and benefits of using TMP-SMX as prophylaxis for SAB in high-risk populations. [Extracted from the article]

This study investigates the frequency of infections in autoimmune blistering disease (AIBD) patients treated with rituximab and evaluates the difference in infectious complications in patients on concomitant antibiotic and/or antiviral prophylaxis. The study retrospectively reviewed 43 AIBD patients who received rituximab over a five-year interval. The patients were categorized based on prophylaxis type (antibiotic, antiviral, or both) and concomitant immunosuppression status, which we defined as treatment with an immunosuppressive medication during the time frame they were given Rituximab. Our findings suggest that concomitant immunosuppression alongside rituximab did not significantly increase the risk of developing infectious complications compared to rituximab monotherapy. Results revealed that 34.4% of patients with concomitant immunosuppression had a secondary bacterial infection, defined as bacterial complications requiring hospitalization, consistent with prior studies. Moreover, antibiotic prophylaxis did not significantly reduce infection risk in patients on rituximab, with 45.1% of these patients experiencing bacterial complications. There was an absence of pneumocystis pneumonia in the study population. Despite the small sample size and limited timeline, this study suggests that antibiotic prophylaxis may not significantly mitigate the risk of infections in AIBD patients receiving rituximab, and the risk of infection with concomitant immunosuppression with rituximab requires additional investigation for definitive causal risk. [ABSTRACT FROM AUTHOR]

Introduction: Urinary tract infections (UTI) are one of the most common infections encountered in the emergency department (ED) with an estimated 2-3 million annual visits.  Commonly prescribed antibiotics for UTIs have shown growing rates of resistance.  Previous studies lack direction on improving UTI treatment based on the labs available to the bedside clinician.   Methods: We sought to determine if antibiotic resistance in UTIs was related to demographics, urinalysis, and history of renal failure or kidney stones. We conducted an analysis of 892 women ≥18 years of age discharged from the ED with a UTI diagnosis. We assessed predictors of nitrofurantoin resistance, cefazolin resistance, ciprofloxacin resistance, and trimethoprim-sulfamethoxazole resistance using unadjusted and multivariable logistic regression models. Results: Antibiotic resistance was 13.6% for nitrofurantoin, 11.9% for cefazolin, 12.8% for ciprofloxacin, and 17.1% for trimethoprim-sulfamethoxazole. In multivariable analysis, significant independent associations with an increased likelihood of resistance to nitrofurantoin were observed for less urine blood (OR [per 1 category increase of score] 0.81; P = 0.02); greater mucous (OR [per 1 category increase of score] 1.22; P = 0.02); less specific gravity urine (OR [per 1 category increase] 0.87; P = 0.04), and presence of any history of kidney stones (OR 3.24; P = 0.01). There were no significant predictors for cefazolin resistance (all P ≥0.06); age was the only significant predictor of ciprofloxacin resistance (OR per 10 year increase] 1.10, P = 0.05), and lower specific gravity urine was significantly associated with an increased risk of resistance to trimethoprim- sulfamethoxazole (OR [per 1 category increase] 0.88, P = 0.04). Conclusion: Women with any history of kidney stones may have bacteriuria resistant to nitrofurantoin, suggesting that providers might consider alternative antibiotic therapies in this scenario.

Purpose: Fosfomycin has been used more frequently in managing uncomplicated urinary tract infections (UTIs) due to decreased compliance and increased multidrug-resistant bacteria. The aim of this network meta-analysis was to assess the efficacy of Fosfomycin compared to Nitrofurantoin, Trimethoprim–Sulfamethoxazole (TMP-SMX), and Ciprofloxacin in terms of clinical and microbiological cure alongside with other measurements. Materials and methods: We searched MEDLINE, Embase, and Cochrane Central Register of Controlled Trials (CENTRAL). We included randomized control trials (RCTs) with uncomplicated UTI patients who received Fosfomycin, Nitrofurantoin, TMP-SMX, or Ciprofloxacin and reported the clinical or microbiological cure. We used Cochrane Risk of Bias Assessment Tool to assess the included studies’ quality. R-software was used for all statistical analysis. We ranked all antibiotics using the netrank function which yielded P scores. Frequentist network meta-analysis was used to assess the efficacy of all outcomes. Results: We included 13 RCTs with a total number of 3856 patients that showed Fosfomycin ranked the highest among the other antibiotics with respect to clinical cure (P-score = 0.99) and microbiological cure (P-score = 0.99) while Ciprofloxacin ranked the lowest (P-score = 0.11 and 0.02, respectively). Moreover, Ciprofloxacin yielded the highest relapse rate (P-score = 1), whereas TMP-SMX had the lowest relapse rate (P-score = 0.07). As for the adverse events, Ciprofloxacin demonstrated the highest adverse events as opposed to Fosfomycin (P-score = 0.98 and 0.05, respectively). Conclusion: The network meta-analysis demonstrated that Fosfomycin is the most effective antibiotic in treating uncomplicated UTIs with respect to clinical cure, microbiological cure, and adverse events profile. [ABSTRACT FROM AUTHOR]

We performed a retrospective study to evaluate the risk factors for acquiring Pneumocystis pneumonia (PCP) by pharmacologically immunosuppressed HIV-negative patients. Patients who received corticosteroids, immunosuppressive agents, anticancer agents, and radiotherapy with or without trimethoprim-sulfamethoxazole (TMP-SMX) at Himeji Medical Center between 2010 and 2021 were evaluated. Drugs and doses of the treatments for each patient were divided by month into person-month units. Each person-month datum includes information on the administered drug (or radiotherapy), average doses, and whether the patient had PCP during the corresponding month. ROC curves with person-month data were generated for each treatment, and AUCs >0.7 were identified as possessing positive classification utility. The risks for PCP according to gender, age (grouped by median) and each treatment were examined by univariate analysis, followed by multivariate analysis to identify independent factors. Of a total of 17,733 patients (214,676 person-months), 32 developed PCP. The cut-off values by ROC analysis were 13.7 mg/day for corticosteroid (prednisolone equivalent), 0.92 mg/day (6.45 mg/week) for methotrexate (MTX), and 34.3 mg/day for TMP-SMX. The cut-off values for other treatments could not be estimated. The above three drugs and male sex were significant variables in univariate analysis and were all confirmed as independent factors by multivariate analysis. The results suggest that a monthly average dose of ≥13.7 mg/day of prednisolone, ≥0.92 mg/day of MTX and male sex are significant independent risk factors for PCP, and that prophylaxis with ≥34.3 mg/day of TMP-SMX is to be recommended. [ABSTRACT FROM AUTHOR]

OBJECTIVES: Trimethoprim-sulfamethoxazole (TMP-SMX)-associated severe acute respiratory distress syndrome (ARDS) has gone underrecognized. We propose the first disease definition and clinical evaluation for a novel adverse drug reaction (ADR) based on a series of recently identified rare cases of life-threatening ADRs. DESIGN: A retrospective study was conducted. All medical records were evaluated. Available pathology samples were sent to Massachusetts General for clinical consultation. Blood samples from surviving patients were obtained and human leukocyte antigen (HLA) analysis was performed by the Children’s Mercy Hospital Genomic Center and Vanderbilt University Medical Center. SETTING: U.S. ICUs, 1996–2021. PATIENTS: Nineteen young patients (10–37) were identified. Patients were previously healthy, with no preexisting pulmonary disease, no other cause for respiratory failure, and no chronic history of smoking/vaping. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Through our retrospective analysis, we analyzed clinical characteristics associated with TMP-SMX. Pathology samples were reviewed, and HLA analysis was performed on available samples by the study team or as standard of care at treatment hospitals in some cases. In 19 critically ill patients, we identified a pattern of severe respiratory failure requiring ICU admission, mechanical ventilation, and frequent extracorporeal membrane oxygenation use. We describe the first three-part clinical diagnosis and evaluation strategy: 1) Clinical definition: Unexplained severe respiratory failure in a patient receiving greater than or equal to 6 days of TMP-SMX at treatment dose (not prophylaxis). TMP-SMX ARDS is a diagnosis of exclusion. 2) Genetic association: One hundred percent of currently available TMP-SMX respiratory failure patient genomic data, (n = 11) have been carriers of both HLA-B*07:02 and HLA-C*07:02 alleles. HLA allele evaluation could be considered in patients with suspected TMP-SMX respiratory failure. 3) Lung pathology: A unique pulmonary pathologic pattern of lung injury termed diffuse alveolar injury with delayed epithelialization has been observed in these cases. In suspected cases, surgical lung biopsy early in the clinical course could be considered. CONCLUSIONS: TMP-SMX is a commonly prescribed antibiotic. However, we find it imperative to share this relatively rare but life-threatening condition with clinicians as the mortality rate approaches 40%. [ABSTRACT FROM AUTHOR]

Zhiqiang Fan,1 Yang He,1 Wei Sun,2 Zuojun Li,2 Min Zhu,3 Chunjiang Wang2 1Department of Pharmacy, The First Hospital of Hunan University of Chinese Medicine, Changsha, Hunan, 410007, People’s Republic of China; 2Department of Pharmacy, The Third Xiangya Hospital, Central South University, Changsha, Hunan, 410013, People’s Republic of China; 3Department of Ophthalmology, Central South University, Changsha, Hunan, 410013, People’s Republic of ChinaCorrespondence: Chunjiang Wang, Department of Pharmacy, The Third Xiangya Hospital, Central South University, No. 138 Tongzipo Road, YueLu District, Changsha, Hunan, 410013, People’s Republic of China, Email wongcj@csu.edu.cnObjective: Trimethoprim sulfamethoxazole (TMP-SMX) is related to aseptic meningitis. However, a detailed description of its phenotype is lacking, which easily leads to misdiagnosis. The purpose of this article is to explore the clinical characteristics of TMP-SMX-induced aseptic meningitis (TSIAM).Methods: We collected literature related to TSIAM published before July 31, 2023, by searching Chinese and English databases. Data were extracted and analyzed descriptively.Results: The 55 patients were mostly female (60.0%), with a median age of 43 years (range: 2.5– 90 years). The first onset time was from a few minutes to 3 months after administration, and the time of reonset was within 12 hours. Fever (98.2%), headache (78.2%), altered mental status (42.3%), nausea and vomiting (41.8%), and neck pain (34.5%) were the most common symptoms. In severe cases, patients presented with low blood pressure, seizures, unconsciousness, or coma. Typical cerebrospinal fluid analysis showed elevated white blood cell counts, with polymorphonuclear leukocytes predominating, elevated protein levels, and normal glucose levels. Brain imaging usually showed no abnormalities. Symptoms resolved rapidly after the discontinuation of TMP-SMX, within a median time of 2 days (range: 1, 60). Readministration of TMP-SMX led to another relapse of aseptic meningitis. Aseptic meningitis usually culminated in a full recovery, although one patient experienced permanent paraplegia.Conclusion: Clinicians should be aware that aseptic meningitis is a rare adverse effect of TMP-SMX. TMP-SMX should be discontinued in patients with TSIAM to reduce unnecessary testing and treatment, and readministration of TMP-SMX should be avoided.Keywords: aseptic meningitis, trimethoprim-sulfamethoxazole, drug-induced aseptic meningitis, headache, trimethoprim

Abstract Background Antibiotic prophylaxis is recommended during ANCA-associated vasculitis (AAV) induction. We aimed to describe the frequency, persistence, and factors associated with trimethoprim-sulfamethoxazole (TMP-SMX) use in an adult population sample with granulomatosis with polyangiitis (GPA) treated with rituximab (RTX). Methods We identified adults with GPA treated with RTX within the Merative™ Marketscan® Research Databases (2011–2020). TMP-SMX prophylaxis was defined as a $$\ge$$ ≥ 28-day prescription dispensed within a month of starting RTX. We estimated TMP-SMX persistence, allowing prescription refill gaps of 30 days. Multivariable logistic regression and Cox proportional hazards regression assessed the factors associated with baseline TMP-SMX use and persistence, respectively. Covariates included age, sex, calendar year, insurance type, immunosuppressant use, hospitalization, and co-morbidities. Results Among 1877 RTX-treated GPA patients, the mean age was 50.9, and 54% were female. A minority (n = 426, 23%) received TMP-SMX with a median persistence of 141 (IQR 83–248) days. In multivariable analyses, prophylaxis was associated with prednisone use in the month prior to RTX ( $$\ge$$ ≥ 20 mg/day vs none, OR 3.96; 95% CI 3.0–5.2; 1–19 mg/day vs none, OR 2.63; 95% CI 1.8–3.8), and methotrexate use (OR 1.48, 95% CI 1.04–2.1), intensive care (OR 1.95; 95% CI 1.4–2.7), and non-intensive care hospitalization (OR 1.56; 95% CI 1.2–2.1) in the 6 months prior to RTX. Female sex (OR 0.63; 95% CI 0.5–0.8) was negatively associated with TMP-SMX use. Conclusions TMP-SMX was dispensed to a minority of RTX-treated GPA patients, more often to those on glucocorticoids and with recent hospitalization. Further research is needed to determine the optimal use and duration of TMP-SMX prophylaxis following RTX in AAV.

Abstract Background Taiwanese patients frequently experience severe hepatotoxicity associated with high‐dose methotrexate (HD‐MTX) treatment, which interferes with subsequent treatment. Drug–drug interactions occur when MTX is used in combination with proton pump inhibitors (PPIs), trimethoprim‐sulfamethoxazole (TMP‐SMX), or non‐steroidal anti‐inflammatory drugs (NSAIDs). In East Asia, real‐world analyses on the effects of co‐medication and other potential risk factors on the clinical course of HD‐MTX‐mediated acute hepatotoxicity in patients with osteogenic sarcoma (OGS) are limited. Methods This cohort study included patients with newly diagnosed OGS who were treated with HD‐MTX between 2009 and 2017 at Taipei Veterans General Hospital. We collected data on the clinical course of HD‐MTX‐mediated acute hepatotoxicity, co‐medications, and other potential risk factors, and analyzed the effects of these factors on the clinical course of HD‐MTX‐mediated acute hepatotoxicity. Results Almost all patients with OGS treated with HD‐MTX developed acute hepatotoxicity with elevated alanine aminotransferase (ALT) levels. Most patients with Grade 3–4 ALT elevation failed to recover to Grade 2 within 7 days. Women and children are high‐risk subgroups for HD‐MTX‐mediated elevation of ALT levels. Age is a factor that contributes to the pharmacokinetic differences of HD‐MTX. However, the concurrent use of PPIs, TMP‐SMX, or NSAIDs did not affect the elimination of MTX when administered with adequate supportive therapy. Conclusions Co‐administration of PPIs, TMP‐SMX, or NSAIDs may have limited effects on acute hepatotoxicity in well‐monitored and adequately pre‐medicated patients with OGS undergoing chemotherapy with HD‐MTX. Clinicians should pay particular attention to ALT levels when prescribing HD‐MTX to children and women.

Abstract Background The number of pneumocystis pneumonia (PCP) cases is increasing in immunocompromised patients without human immunodeficiency virus infection (HIV), causing serious morbidity with high mortality. Trimethoprim/sulfamethoxazole (TMP/SMZ) monotherapy has limited effectiveness in the treatment of PCP. Clinical data on whether initial caspofungin plus TMP/SMZ for this disease is superior to monotherapy in non-HIV-infected patients are limited. We aimed to compare the clinical effectiveness of these regimens for severe PCP in non-HIV patients. Methods A retrospective study reviewed 104 non-HIV-infected patients with confirmed PCP in the intensive care unit between January 2016 and December 2021. Eleven patients were excluded from the study because TMP/SMZ could not be used due to severe hematologic disorders or clinical data were missing. All enrolled patients were divided into three groups according to different treatment strategies: Group 1 received TMP/SMZ monotherapy, Group 2 received caspofungin combined with TMP/SMZ as first-line therapy, and Group 3 initially received TMP/SMZ monotherapy and later received caspofungin as salvage therapy. The clinical characteristics and outcomes were compared among the groups. Results A total of 93 patients met the criteria. The overall positive response rate of anti-PCP treatment was 58.06%, and the overall 90-day all-cause mortality rate was 49.46%. The median APACHE II score was 21.44. The concurrent infection rate was 74.19%, among whom 15.05% (n = 14) of those patients had pulmonary aspergillosis, 21.05% (n = 20) had bacteremia, and 23.65% (n = 22) had CMV infections. The patients who received initial caspofungin combination with TMP/SMZ had the best positive response rate (76.74%) compared to others (p = 0.001). Furthermore, the group that received initial caspofungin combined with TMP/SMZ had a 90-day all-cause mortality rate (39.53%) that was significantly different from that of the shift group (65.51%, p = 0.024), but this rate showed no statistically significant difference compared with that in the monotherapy group (48.62%, p = 0.322). None of the patients had serious adverse events from caspofungin therapy. Conclusions For non-HIV-infected patients with severe PCP, initial combination therapy with caspofungin and TMP/SMZ is a promising first-line treatment option compared with TMP/SMZ monotherapy and combination therapy as salvage therapy.

Background/purpose: The study was to assess the relationship between antibiotic therapy and the outcome in intensive care unit (ICU) patients with Stenotrophomonas maltophilia bloodstream infection (BSI). Methods: ICU patients with monomicrobial S. maltophilia BSI from January 2004 to December 2019 were included and divided into two groups—those with- and without appropriate antibiotic therapy after BSI—for comparison. The primary outcome was the relationship between appropriate antibiotic therapy and 14-day mortality. The secondary outcome was the influence of different antibiotic therapies: levofloxacin- and trimethoprim–sulfamethoxazole (TMP/SMX)-containing regimens, on 14-day mortality. Results: A total of 214 ICU patients were included. Patients received appropriate antibiotic therapy (n = 133) after BSI had a lower 14-day mortality than those (n = 81) without appropriate antibiotic therapy (10.5% vs. 46.9%, p 0.05). After a propensity score matching, the results is consistent that 14-day mortality were lower in patients with appropriate antibiotic therapy than those without appropriate antibiotic therapy (11.5% vs. 39.3%, p

Trimethoprim-sulfamethoxazole (TMP-SMX) is a broad spectrum antibiotic in use for more than 50 years. It has an important indication as first line agent in the prophylaxis of opportunistic infections, particularly Pneumocystis jirovecii pneumonia (PJP), in immunosuppressed patients. For those who have a history of allergy or severe intolerance to TMP-SMX, pentamidine, dapsone or atovaquone may be substituted; however there is evidence that TMP-SMX offers superior coverage for PJP, toxoplasmosis, and nocardiosis. Compared to pentamidine, it has the added benefit of cost-effectiveness and self-administration as opposed to required hospital attendance for administration. Many patients who report a history of allergy or adverse reaction to TMP-SMX (or “sulfur allergy”) will be found not to be allergic; and even those who are allergic may be able to be desensitized. The evaluation and, where appropriate, removal of TMP-SMX allergy label enables the use of TMP-SMX for prophylaxis against opportunistic infections. This is a cost-effective intervention to optimize antimicrobial prescribing and reduce the risk of opportunistic infections in immunosuppressed patients.

Antimicrobials are commonly prescribed and often misunderstood. With more than 50% of hospitalized patients receiving an antimicrobial agent at any point in time, judicious and optimal use of these drugs is paramount to advancing patient care. This narrative will focus on myths relevant to nuanced consultation from infectious diseases specialists, particularly surrounding specific considerations for a variety of antibiotics. [ABSTRACT FROM AUTHOR]

Background Trimethoprim–sulfamethoxazole (TMP–SMX) is active against most Staphylococcus aureus isolates but is not widely used for the treatment of pediatric osteoarticular infections. Methods This was a comparative effectiveness study of hospitalized patients ≤18 years treated with TMP–SMX vs. other antibiotic regimens for acute osteoarticular infections between 2016 and 2021 at 3 hospitals using inverse probability of treatment weighted propensity score analysis. The primary outcome was treatment failure, a composite of unanticipated emergency department (ED) or outpatient visits, hospital readmissions, extension, or change of antibiotic therapy due to inadequate clinical response, or death, all within 6 months after completing antibiotics. The secondary outcome was antibiotic-associated adverse events (AEs) within 6 months. The exposed group for the treatment failure analysis included children who received ≥7 days of TMP–SMX and did not experience treatment failure while on another antibiotic. Children receiving at least 1 dose of TMP–SMX were the exposed group for the AE analysis. Results One-hundred and sixteen patients met eligibility criteria; 26 (22.4%) patients were classified into the TMP–SMX cohort and 90 (77.6%) into the other antibiotics cohort (most commonly clindamycin, vancomycin, and cefazolin). There was no significant difference in treatment failure between TMP–SMX and other antibiotics (43% vs. 19%; 95% CI.9–10.4). More patients in the TMP–SMX cohort experienced an unplanned ED or outpatient visit (OR 4.8, 95% CI 1.3–17.8). There was no difference in hospital readmission, antibiotic change, or duration extension. Exposure to TMP–SMX was associated with more AEs (41% vs. 19%, P  = .012). Conclusions Treatment with TMP–SMX was not associated with greater clinical failure but was associated with more AEs compared to alternative agents for the treatment of pediatric acute osteoarticular infections. [ABSTRACT FROM AUTHOR]

Background: Nocardia is an opportunistic pathogen that primarily affects immunocompromised individuals, including solid organ transplant (SOT) recipients. Up to 2.65% of SOT recipients develop nocardiosis; however, few studies have examined risk factors and prophylaxis for nocardiosis. Methods: We performed a multicenter, matched nested case‐control study of adult SOT recipients with culture‐confirmed nocardiosis from 2000 through 2020. Controls were matched up to 2:1 by sex, first transplanted organ, year of transplant, transplant center, and adequate post‐transplant follow‐up. Multivariable conditional logistic regression was performed to analyze associations with nocardiosis. Cox proportional hazards regression compared 12‐month mortality between infection and uninfected patients. Results: One hundred and twenty‐three SOT recipients were matched to 245 uninfected controls. Elevated calcineurin inhibitor level, acute rejection, cytomegalovirus infection, lymphopenia, higher prednisone dose, and older age were significantly associated with nocardiosis while trimethoprim‐sulfamethoxazole prophylaxis was protective (odds ratio [OR].34; 95% confidence interval [CI].13‐.84). The effect of prophylaxis was similar, though not always statistically significant, in sensitivity analyses that only included prophylaxis dosed more than twice‐per‐week (OR.30; 95% CI.11‐.80) or restricted to years 2015‐2020 (OR.33, 95% CI.09‐1.21). Nocardiosis was associated with increased 12‐month mortality (hazard ratio 5.47; 95% confidence interval 2.42‐12.35). Conclusions: Multiple measures of immunosuppression and lack of trimethoprim‐sulfamethoxazole prophylaxis were associated with nocardiosis in SOT recipients. Effectiveness of prophylaxis may be related to trimethoprim‐sulfamethoxazole dose or frequency. Trimethoprim‐sulfamethoxazole should be preferentially utilized over alternative agents in SOT recipients with augmented immunosuppression or signs of heightened immunocompromise. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Sulfonamides are widely used to treat and prevent various bacterial and opportunistic infections. The aim of this study was to describe the clinical presentation and outcomes of a large cohort of patients with sulfonamide hepatotoxicity. METHODS: Between 2004 and 2020, 105 patients with hepatotoxicity attributed to trimethoprim/sulfamethoxazole (TMP-SMZ) (n 5 93) or other sulfonamides (n 5 12) were enrolled. Available liver biopsies were reviewed by a single hepatopathologist. RESULTS: Among the 93 TMP-SMZ cases, 52% were female, 7.5% younger than 20 years, and the median time to drug-induced liver injury (DILI) onset was 22 days (range: 3-157). Younger patients were significantly more likely to have rash, fever, eosinophilia, and a hepatocellular injury pattern at onset that persisted at the peak of liver injury compared with older patients (P < 0.05). The 18 (19%) TMP-SMZ patients treated with corticosteroids had more severe liver injury and a higher mortality but a trend toward more rapid normalization of their laboratory abnormalities compared with untreated patients. During follow-up, 6.2% of the TMP-SMZ patients died or underwent liver transplantation. Chronic DILI developed in 20% and was associated with cholestatic injury at onset and higher peak total bilirubin levels. DISCUSSION: Sulfonamide hepatotoxicity is characterized by a short drug latency with frequent hypersensitivity features at onset. Subject age is an important determinant of the laboratory profile at presentation, and patients with cholestasis and higher total bilirubin levels were at increased risk of developing chronic DILI. Corticosteroids may benefit a subgroup of patients with severe injury, but further studies are needed. [ABSTRACT FROM AUTHOR]

B-cell lymphoma is the most prevalent type of non-Hodgkin lymphoma, for which the standard treatment regimen includes rituximab combined with CHOP. However, some patients may develop interstitial pneumonitis (IP), which can be caused by various factors; one of the most important factors is Pneumocystis jirovecii. It is crucial to investigate the pathophysiology of IP and implement preventive measures since IP can be fatal for some people. The data were collected from the First Affiliated Hospital, Zhejiang University School of Medicine, where patients with B-cell lymphoma received the R-CHOP/R-CDOP regimen with or without prophylactic use of trimethoprim-sulfamethoxazole (TMP-SMX). Multivariable logistic regression and propensity score matching (PSM) were used to investigate any potential association. Eight hundred thirty-one patients with B-cell lymphoma were classified into two groups: the non-prophylaxis group without TMP-SMX (n=699) and the prophylaxis group with TMP-SMX (n = 132). IP occurred in 66 patients (9.4%, all in the non-prophylaxis group), with an onset median of three cycles of chemotherapy. Multiple logistic regression analysis demonstrated that IP incidence was associated with pegylated liposome doxorubicin (OR=3.29, 95% CI 1.84–5.90, P<0.001). After utilizing a 1:1 matching algorithm for PSM, 90 patients from each group were obtained. There was a statistical difference between the two cohorts in the IP incidence (non-prophylaxis 12.2% vs prophylaxis 0.0%, P <0.001). The prophylactic use of TMP-SMX could prevent the occurrence of IP whose risk factor was pegylated liposome doxorubicin after chemotherapy for B-cell lymphoma. [ABSTRACT FROM AUTHOR]

Stenotrophomonas maltophilia is an emerging multidrug-resistant organism with an increasing frequency of hospital-acquired infections predominantly in developing countries. The purpose of this study was to determine the antibiotic resistance and frequency of the smeD, class 1 integron, and sul1 genes in clinical isolates of S. maltophilia in two Iranian provinces. From January 2020 to September 2021, 38 clinical isolates of S. maltophilia were collected from patients in hospitals in Tabriz and Sanandaj provinces of Iran. S. maltophilia isolates were confirmed by standard bacteriological tests and 16S rRNA gene PCR. Disk diffusion and the MIC test strip methods were used to determine the antibiotic resistance patterns. PCR was performed to investigate the presence of smeD, class 1 integron, and sul1 genes. The antimicrobial test for the isolated S. maltophilia showed a high level of sensitivity against most of the antibiotics used. Maximum sensitivity was recorded for ciprofloxacin (100% (38/38)) and levofloxacin 100% (38/38), followed by ceftazidime (97.36% (37/38)), trimethoprim-sulfamethoxazole (81.57% (31/38)), ticarcillin-clavulanate (60.52% (23/38)), and piperacillin-tazobactam (55.26% (21/38)). We observed a high prevalence of smeD (100% (38/38)) and class 1 integron (94.73% (36/38)) genes in the isolates, and none of the isolates carried the sul1 gene. The findings from this study indicate that resistance to trimethoprim-sulfamethoxazole was not observed, and still, trimethoprim-sulfamethoxazole is the best drug with desirable antimicrobial effect in the treatment of nosocomial infections caused by S. maltophilia strains. Despite the observation of a high number of class 1 integron, the sul1 gene was not observed, which indicates the role of this gene in high-level trimethoprim-sulfamethoxazole resistance and not having a role in low-level resistance. Based on our results, clinical microbiology laboratories need continuous surveillance of resistance rates to trimethoprim-sulfamethoxazole, because of the possibility of S. maltophilia acquiring trimethoprim-sulfamethoxazole-resistance by mobile gen elements. [ABSTRACT FROM AUTHOR]

Background/Purpose: Nocardiosis is an uncommon infectious disease. This study aimed to assess the clinical outcome of patients with nocardiosis and examine the antimicrobial susceptibility profiles of Nocardia spp. isolated. Methods: We retrospectively reviewed the medical records of all inpatients diagnosed with nocardiosis between 2011 and 2021. The identification of Nocardia spp. at the species level was performed with the use of MALDI-TOF and 16S rRNA assays. The antimicrobial susceptibility of Nocardia spp. was performed using the microbroth dilution method. Factors associated with 90-day all-cause mortality were identified in multivariate logistic regression analysis. Results: Of 60 patients with nocardiosis in the 11-year study period, the lungs (55.0%) were the most common site of involvement, followed by the skin and soft tissue (45.0%). Twenty-two patients (36.7%) died within 90 days following the diagnosis. All of the Nocardia isolates were susceptible to trimethoprim-sulfamethoxazole, linezolid, and amikacin, whereas more than 70% of the isolates were not susceptible to ciprofloxacin, imipenem-cilastatin, moxifloxacin, cefepime, and clarithromycin. Nocardiosis involving the lungs (relative risk [RR], 9.99; 95% confidence interval [CI], 1.52–65.50; p = 0.02), nocardiosis involving the skin and soft tissue (RR, 0.15; 95% CI, 0.02–0.92; p = 0.04), and treatment with trimethoprim-sulfamethoxazole (RR, 0.14; 95% CI, 0.03–0.67; p = 0.01) were independently associated with 90-day all-cause mortality. Conclusions: Nocardia spp. identified between 2011 and 2021 remained fully susceptible to trimethoprim-sulfamethoxazole, linezolid, and amikacin. Nocardiosis of the lungs, skin and soft tissue infection, and treatment with trimethoprim-sulfamethoxazole were independently associated with 90-day all-cause mortality.

Jun Hirai,1,2 Nobuaki Mori,1,2 Hideo Kato,3 Nobuhiro Asai,1,2 Mao Hagihara,4 Hiroshige Mikamo1,2 1Department of Clinical Infectious Diseases, Aichi Medical University Hospital, Nagakute, Aichi, Japan; 2Department of Infection Control and Prevention, Aichi Medical University Hospital, Nagakute, Aichi, Japan; 3Department of Pharmacy, Mie University Hospital, Mie, Japan; 4Department of Molecular Epidemiology and Biomedical Sciences, Aichi Medical University, Nagakute, Aichi, JapanCorrespondence: Jun Hirai, Department of Clinical Infectious Diseases, Aichi Medical University Hospital, 1-1, Yazako-karimata, Nagakute, Aichi, 480-1195, Japan, Tel +81-561-62-3311, Fax +81-561-76-2673, Email hiraichimed@gmail.comAbstract: Currently, atovaquone is not recommended for treating severe Pneumocystis jirovecii pneumonia (PCP) due to insufficient evidence in clinical studies. This report describes a case of severe PCP in a human immunodeficiency virus (HIV)-negative immunosuppressed patient who was successfully treated with oral atovaquone and corticosteroids. A 63-year-old Japanese woman complained of fever and dyspnea for 3 days. She had been treated with oral prednisolone (30 mg/day) for interstitial pneumonia for 3 months without PCP prophylaxis. Although we could not confirm P. jirovecii from the respiratory specimen, a diagnosis of PCP was indicated by marked elevation of serum beta-D-glucan levels and bilateral ground-glass opacities in the lung fields. Based on the arterial blood gas test results (alveolar-arterial oxygen difference > 45 mmHg), the disease status of PCP was defined as severe. Trimethoprim-sulfamethoxazole (SXT) is the first-line drug for treating severe PCP. However, given the patient’s history of SXT-induced toxic epidermal necrolysis, she was administered atovaquone instead of SXT. Her clinical symptoms and respiratory condition gradually improved, with a 3-week treatment showing a good clinical course. Previous clinical studies on atovaquone have only been conducted in HIV-positive patients with mild or moderate PCP. Accordingly, the clinical efficacy of atovaquone for severe PCP cases or PCP in HIV-negative patients remains unclear. There is a rising incidence of PCP among HIV-negative patients, given the increasing number of patients receiving immunosuppressive medications; moreover, atovaquone has less severe side effects than SXT. Therefore, there is a need for further clinical investigation to confirm the efficacy of atovaquone in cases of severe PCP, especially among HIV-negative patients. In addition, it also remains unclear whether corticosteroids are beneficial for severe PCP in non-HIV patients. Thus, the use of corticosteroids in cases of severe PCP in non-HIV patients should also be investigated.Keywords: Pneumocystis pneumonia, severe, atovaquone, trimethoprim-sulfamethoxazole, corticosteroid

Stenotrophomonas maltophilia is an opportunistic pathogen and frequent cause of serious nosocomial infections. Patient populations at greatest risk for these infections include the immunocompromised and those with chronic respiratory illnesses and prior antibiotic exposure, notably to carbapenems. Its complex virulence and resistance profile drastically limit available antibiotics, and incomplete breakpoint and pharmacokinetic/pharmacodynamic (PK/PD) data to inform dose optimization further complicates therapeutic approaches. Clinical comparison data of first‐line agents, including trimethoprim‐sulfamethoxazole (TMP‐SMX), quinolones, and minocycline, are limited to conflicting observational data with no clear benefit of a single agent or combination therapy. Newer antibiotic approaches, including cefiderocol and aztreonam‐ avibactam, are promising alternatives for extensively drug‐resistant isolates; however, clinical outcomes data are needed. The potential clinical utility of bacteriophage for compassionate use in treating S. maltophilia infections remains to be determined since data is limited to in‐vitro and sparse in‐vivo work. This article provides a review of available literature for S. maltophilia infection management focused on related epidemiology, resistance mechanisms, identification, susceptibility testing, antimicrobial PK/PD, and emerging therapeutic strategies. [ABSTRACT FROM AUTHOR]

Background: The number of pneumocystis pneumonia (PCP) cases is increasing in immunocompromised patients without human immunodeficiency virus infection (HIV), causing serious morbidity with high mortality. Trimethoprim/sulfamethoxazole (TMP/SMZ) monotherapy has limited effectiveness in the treatment of PCP. Clinical data on whether initial caspofungin plus TMP/SMZ for this disease is superior to monotherapy in non-HIV-infected patients are limited. We aimed to compare the clinical effectiveness of these regimens for severe PCP in non-HIV patients. Methods: A retrospective study reviewed 104 non-HIV-infected patients with confirmed PCP in the intensive care unit between January 2016 and December 2021. Eleven patients were excluded from the study because TMP/SMZ could not be used due to severe hematologic disorders or clinical data were missing. All enrolled patients were divided into three groups according to different treatment strategies: Group 1 received TMP/SMZ monotherapy, Group 2 received caspofungin combined with TMP/SMZ as first-line therapy, and Group 3 initially received TMP/SMZ monotherapy and later received caspofungin as salvage therapy. The clinical characteristics and outcomes were compared among the groups. Results: A total of 93 patients met the criteria. The overall positive response rate of anti-PCP treatment was 58.06%, and the overall 90-day all-cause mortality rate was 49.46%. The median APACHE II score was 21.44. The concurrent infection rate was 74.19%, among whom 15.05% (n = 14) of those patients had pulmonary aspergillosis, 21.05% (n = 20) had bacteremia, and 23.65% (n = 22) had CMV infections. The patients who received initial caspofungin combination with TMP/SMZ had the best positive response rate (76.74%) compared to others (p = 0.001). Furthermore, the group that received initial caspofungin combined with TMP/SMZ had a 90-day all-cause mortality rate (39.53%) that was significantly different from that of the shift group (65.51%, p = 0.024), but this rate showed no statistically significant difference compared with that in the monotherapy group (48.62%, p = 0.322). None of the patients had serious adverse events from caspofungin therapy. Conclusions: For non-HIV-infected patients with severe PCP, initial combination therapy with caspofungin and TMP/SMZ is a promising first-line treatment option compared with TMP/SMZ monotherapy and combination therapy as salvage therapy. [ABSTRACT FROM AUTHOR]

Mycophenolic acid (MPA) and trimethoprim-sulfamethoxazole (TMP-SMX) are commonly prescribed together in certain groups of patients, including solid organ transplant recipients. However, little is known about the pharmacokinetic drug–drug interactions (DDIs) between these two medications. Therefore, the present study aimed to determine the effects of TMP-SMX on MPA pharmacokinetics in humans and to find out the relationship between MPA pharmacokinetics and gut microbiota alteration. This study enrolled 16 healthy volunteers to take a single oral dose of 1000 mg mycophenolate mofetil (MMF), a prodrug of MPA, administered without and with concurrent use of TMP-SMX (320/1600 mg/day) for five days. The pharmacokinetic parameters of MPA and its glucuronide (MPAG) were measured using high-performance liquid chromatography. The composition of gut microbiota in stool samples was profiled using a 16S rRNA metagenomic sequencing technique during pre- and post-TMP-SMX treatment. Relative abundance, bacterial co-occurrence networks, and correlations between bacterial abundance and pharmacokinetic parameters were investigated. The results showed a significant decrease in systemic MPA exposure when TMP-SMX was coadministered with MMF. Analysis of the gut microbiome revealed altered relative abundance of two enriched genera, namely the genus Bacteroides and Faecalibacterium, following TMP-SMX treatment. The relative abundance of the genera Bacteroides, [Eubacterium] coprostanoligenes group, [Eubacterium] eligens group, and Ruminococcus appeared to be significantly correlated with systemic MPA exposure. Coadministration of TMP-SMX with MMF resulted in a reduction in systemic MPA exposure. The pharmacokinetic DDIs between these two drugs were attributed to the effect of TMP-SMX, a broad-spectrum antibiotic, on gut microbiota-mediated MPA metabolism. [ABSTRACT FROM AUTHOR]

Background Trimethoprim-sulfamethoxazole (TMP-SMX) can cause hyperkalemia by reducing renal potassium excretion. We assessed the risk of hyperkalemia after initiating TMP-SMX versus amoxicillin and determined if this risk is modified by a patient's baseline kidney function [estimated glomerular filtration rate (eGFR)]. Methods We conducted a population-based cohort study in Ontario, Canada involving adults ≥66 years of age newly treated with TMP-SMX (n  = 58 999) matched 1:1 with those newly treated with amoxicillin (2008–2020). The primary outcome was a hospital encounter with hyperkalemia defined by a laboratory serum potassium value ≥5.5 mmol/L within 14 days of antibiotic treatment. Secondary outcomes included a hospital encounter with acute kidney injury (AKI) and all-cause hospitalization. Risk ratios (RRs) were obtained using a modified Poisson regression. Results A hospital encounter with hyperkalemia occurred in 269/58 999 (0.46%) patients treated with TMP-SMX versus 80/58 999 (0.14%) in those treated with amoxicillin {RR 3.36 [95% confidence interval (CI) 2.62–4.31]}. The absolute risk of hyperkalemia in patients treated with TMP-SMX versus amoxicillin increased progressively with decreasing eGFR (risk difference of 0.12% for an eGFR ≥60 ml/min/1.73 m2, 0.42% for eGFR 45–59, 0.85% for eGFR 30–44 and 1.45% for eGFR <30; additive interaction P  < .001). TMP-SMX versus amoxicillin was associated with a higher risk of a hospital encounter with AKI [RR 3.15 (95% CI 2.82–3.51)] and all-cause hospitalization [RR 1.43 (95% CI 1.34–1.53)]. Conclusions The 14-day risk of a hospital encounter with hyperkalemia was higher in patients newly treated with TMP-SMX versus amoxicillin and the risk was highest in patients with a low eGFR. [ABSTRACT FROM AUTHOR]

Background: Taiwanese patients frequently experience severe hepatotoxicity associated with high‐dose methotrexate (HD‐MTX) treatment, which interferes with subsequent treatment. Drug–drug interactions occur when MTX is used in combination with proton pump inhibitors (PPIs), trimethoprim‐sulfamethoxazole (TMP‐SMX), or non‐steroidal anti‐inflammatory drugs (NSAIDs). In East Asia, real‐world analyses on the effects of co‐medication and other potential risk factors on the clinical course of HD‐MTX‐mediated acute hepatotoxicity in patients with osteogenic sarcoma (OGS) are limited. Methods: This cohort study included patients with newly diagnosed OGS who were treated with HD‐MTX between 2009 and 2017 at Taipei Veterans General Hospital. We collected data on the clinical course of HD‐MTX‐mediated acute hepatotoxicity, co‐medications, and other potential risk factors, and analyzed the effects of these factors on the clinical course of HD‐MTX‐mediated acute hepatotoxicity. Results: Almost all patients with OGS treated with HD‐MTX developed acute hepatotoxicity with elevated alanine aminotransferase (ALT) levels. Most patients with Grade 3–4 ALT elevation failed to recover to Grade 2 within 7 days. Women and children are high‐risk subgroups for HD‐MTX‐mediated elevation of ALT levels. Age is a factor that contributes to the pharmacokinetic differences of HD‐MTX. However, the concurrent use of PPIs, TMP‐SMX, or NSAIDs did not affect the elimination of MTX when administered with adequate supportive therapy. Conclusions: Co‐administration of PPIs, TMP‐SMX, or NSAIDs may have limited effects on acute hepatotoxicity in well‐monitored and adequately pre‐medicated patients with OGS undergoing chemotherapy with HD‐MTX. Clinicians should pay particular attention to ALT levels when prescribing HD‐MTX to children and women. [ABSTRACT FROM AUTHOR]

The incidence of the opportunistic infection of pneumocystis carini pneumonia(PCP) in patients with autoimmune diseases has increased over recent years, because of the use of glucocorticoids, immunosuppressants, small molecule targeted drugs and biological agents. This group of patients show more rapid progress and higher mortality than human immunodeficiency virus positive patients with PCP. Sulfonamide is the first-line treatment for PCP. Many scholars advocate taking trimethoprim-sulfamethoxazole(TMP-SMZ) for prophylaxis of PCP. However, the adverse effects of sulfonamides and drug resistance cannot be ignored. This article reviews the risk factors for the development of PCP in patients with autoimmune diseases, the effectiveness of PCP prevention with TMP-SMZ, and adverse drug reactions, tolerance, and drug resistance.

Objectives: To evaluate the efficacy and safety of low-dose trimethoprim (TMP)-sulfamethoxazole (SMX) (TMP-SMX) as the primary prophylaxis for Pneumocystis jirovecii pneumonia (PJP) in adult recipients of kidney transplantation. Methods: Three kinds of prescriptions in kidney recipients were documented, including 20 mg TMP/100 mg SMX oral daily, 20 mg TMP/100 mg SMX oral every other day, and nonprophylaxis. The primary outcome was the incidence of PJP in the first 180 days of follow-up after kidney transplantation. The secondary outcomes were changes in renal and liver function. Results: Among the 1469 recipients, 1066 (72.56%) received 20 mg TMP/100 mg SMX daily, 127 (8.65%) received 20 mg TMP/100 mg SMX every other day, and 276 (18.79%) did not have prophylaxis prescription. The 276 recipients in the nonprophylaxis group had 124.92 person-years of follow-up, during which PJP occurred in 29 patients, for an incidence rate of 23.21 (95% confidence interval 15.76-32.72) per 100 person-years. The TMP-SMX daily group and the TMP-SMX every other day group had 524.89 and 62.07 person-years of follow-up, respectively, with no occurrence of PJP. There was no significant difference among the three groups in changes in renal and liver function (P >0.05, respectively). A total of 111 recipients in each group were enrolled in the propensity score matching analysis. It was revealed that the 111 nonprophylaxis recipients had 51.27 person-years of follow-up and 10 PJP cases. Prophylaxis was considered effective because there was a significant difference between the three groups (P