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We report a case of Spiroplasma bloodstream infection in a patient in China who developed pulmonary infection, acute respiratory distress syndrome, sepsis, and septic shock after emergency surgery for type A aortic dissection. One organism closely related to Spiroplasma eriocheiris was isolated from blood culture and identified by whole-genome sequencing.

Background: Bloodstream infections (BSI) in immunocompromised patients suffering from hematological malignancies continue to be an essential cause of morbidity and mortality. Methicillin-resistant Staphylococcus aureus (MRSA)-related BSI in patients with febrile neutropenia (FN) is a life-threatening bacterial infection and extremely challenging to treat. Methods: Blood samples were collected from febrile neutropenic patients. Conventional blood culture and direct PCR identification of 16S rRNA, mecA, femA, nuc, and lukS genes were performed for detection of MRSA. Antibiotic sensitivity profiles of the isolates were investigated using disc diffusion and minimum inhibitory concentration methods. Results: Among 24 positive blood cultures isolates, MRSA (12/24, 50%) was the predominant bacteria followed by coagulase negative staphylococci (CoNS) (6/24, 33.3%). All MRSA isolates were resistant to cefoxitin (MIC ≥ 8 μg/ml), and oxacillin (MIC ≥ 4 μg/ml) and harbored mecA gene. 10/12 MRSA isolates were vancomycin resistant (VRSA) (MIC ≥ 16 μg/ml). PCR for 16S rRNA and mecA genes yielded positive results in 14 negative blood culture samples. Conclusions: We cannot rely on blood culture as a reliable method for BSI diagnosis in patients with FN. 16S rRNA and characteristic MRSA genes PCR showed important role for diagnosis of culture-negative MRSA BSI particularly in patients with preceding prophylactic or empirical antibiotics.

Background: Bloodstream infections (BSI) in immunocompromised patients suffering from hematological malignancies continue to be an essential cause of morbidity and mortality. Methicillin-resistant Staphylococcus aureus (MRSA)-related BSI in patients with febrile neutropenia (FN) is a life-threatening bacterial infection and extremely challenging to treat. Methods: Blood samples were collected from febrile neutropenic patients. Conventional blood culture and direct PCR identification of 16S rRNA, mecA, femA, nuc, and lukS genes were performed for detection of MRSA. Antibiotic sensitivity profiles of the isolates were investigated using disc diffusion and minimum inhibitory concentration methods. Results: Among 24 positive blood cultures isolates, MRSA (12/24, 50%) was the predominant bacteria followed by coagulase negative staphylococci (CoNS) (6/24, 33.3%). All MRSA isolates were resistant to cefoxitin (MIC ≥ 8 μg/ml), and oxacillin (MIC ≥ 4 μg/ml) and harbored mecA gene. 10/12 MRSA isolates were vancomycin resistant (VRSA) (MIC ≥ 16 μg/ml). PCR for 16S rRNA and mecA genes yielded positive results in 14 negative blood culture samples. Conclusions: We cannot rely on blood culture as a reliable method for BSI diagnosis in patients with FN. 16S rRNA and characteristic MRSA genes PCR showed important role for diagnosis of culture-negative MRSA BSI particularly in patients with preceding prophylactic or empirical antibiotics. [ABSTRACT FROM AUTHOR]

Peripheral venous catheter (PVC) complications occur on average in approximately half of patients, necessitating premature PVC removal, suspending administration of ongoing therapies, and catheter replacement. To estimate the current incidence, complications, and costs of bloodstream infection (BSI) attributable to PVCs. Patients with PVC-related BSI (cases) were matched with patients without PVC-related BSI (controls). From January 1st, 2018 to March 31st, 2020, a total of 9833 out of 113,068 patients visiting the emergency department (9%) were hospitalized in a medical ward after insertion of a PVC. Among them, 581 (6%) had at least one positive blood culture. Twenty-five (4%) of these were judged as having a PVC-related BSI. Major complications were noted in nine patients. One patient presented severe sepsis requiring admission to intensive care unit for eleven days followed by thoracic (T4–T7) spondylodiscitis requiring prolonged antimicrobial therapy. Another patient developed mitral valve endocarditis also requiring prolonged antimicrobial therapy. One patient developed a pre-sacral abscess three months after initial PVC infection and required hospital readmission for 19 days for drainage. Median (interquartile range) hospital stay costs were €11,597 (8,479–23,759) for cases and €6,789 (4,019–10,764) for controls, leading to median additional costs of €5,587. Though the risk of developing PVC-related BSI in patients admitted to medical wards may seem low, complications of PVC-related BSI are severe, and associated mortality remains high. The financial resources used to treat these complications could be better spent on prevention, including the use of high-quality materials and technologies, and improved training of healthcare providers. [ABSTRACT FROM AUTHOR]

Objectives: Bloodstream infections (BSIs) acquired in the ICU represent a detrimental yet potentially preventable condition. We determined the prevalence of BSI acquired in the ICU (ICU-onset BSI), pathogen profile, and associated risk factors.Design: Retrospective cohort study.Data Sources: Eighty-five U.S. hospitals in the Cerner Healthfacts Database.Patient Selection: Adult hospitalizations between January 2009 and December 2015 including a (≥ 3 d) ICU stay.Data Extraction and Data Synthesis: Prevalence of ICU-onset BSI (between ICU Day 3 and ICU discharge) and associated pathogen and antibiotic resistance distributions were compared with BSI present on (ICU) admission (ICU-BSI POA ); and BSI present on ICU admission day or Day 2. Cox models identified risk factors for ICU-onset BSI among host, care setting, and treatment-related factors. Among 150,948 ICU patients, 5,600 (3.7%) had ICU-BSI POA and 1,306 (0.9%) had ICU-onset BSI. Of those with ICU-BSI POA , 4,359 (77.8%) were admitted to ICU at hospital admission day. Patients with ICU-onset BSI (vs ICU-BSI POA ) displayed higher crude mortality of 37.9% (vs 20.4%) ( p < 0.001) and longer median (interquartile range) length of stay of 13 days (8-23 d) (vs 5 d [3-8 d]) ( p < 0.001) (considering all ICU stay). Compared with ICU-BSI POA , ICU-onset BSI displayed more Pseudomonas , Acinetobacter , Enterococcus, Candida , and Coagulase-negative Staphylococcus species, and more methicillin-resistant staphylococci, vancomycin-resistant enterococci, ceftriaxone-resistant Enterobacter , and carbapenem-resistant Enterobacterales and Acinetobacter species, respectively. Being younger, male, Black, Hispanic, having greater comorbidity burden, sepsis, trauma, acute pulmonary or gastrointestinal presentations, and pre-ICU exposure to antibacterial and antifungal agents was associated with greater ICU-onset BSI risk after adjusted analysis. Mixed ICUs (vs medical or surgical ICUs) and urban and small/medium rural hospitals were also associated with greater ICU-onset BSI risk. The associated risk of acquiring ICU-onset BSI manifested with any duration of mechanical ventilation and 7 days after insertion of central venous or arterial catheters.Conclusions: ICU-onset BSI is a serious condition that displays a unique pathogen and resistance profile compared with ICU-BSI POA . Further scrutiny of modifiable risk factors for ICU-onset BSI may inform control strategies. [ABSTRACT FROM AUTHOR]

Background: The Malawi-Liverpool Wellcome Trust Clinical Research Programme (MLW) has undertaken sentinel surveillance of bloodstream infection and meningitis at Queen Elizabeth Central Hospital (QECH), Blantyre, Malawi for 20 years. Previously, three epidemics of Salmonella bloodstream infection have been identified. Here we provide updated surveillance data on invasive non-typhoidal Salmonella disease from 2011 – 2019. Methods: Surveillance data describing trends in invasive non-typhoidal Salmonella disease and associated antimicrobial susceptibility profiles are presented for the period January 2011 – December 2019. Results: Between January 2011-December 2019, 128,588 blood cultures and 40,769 cerebrospinal fluid cultures were processed at MLW. Overall, 1.00% of these were positive for S. Typhimurium, 0.10% for S. Enteritidis, and 0.05% positive for other Salmonella species. Estimated minimum incidence of invasive non-typhoidal Salmonella (iNTS) disease decreased from 21/100,000 per year in 2011 to 7/100,000 per year in 2019. Over this period, 26 confirmed cases of Salmonella meningitis were recorded (88.5% S. Typhimurium). Between 2011-2019 there was a substantial decrease in proportion of S. Typhimurium (78.5% to 27.7%) and S. Enteritidis (31.8% in 2011 to 0%) that were multidrug-resistant. Resistance to fluoroquinolones and third-generation generation cephalosporins (3GC) remained uncommon, however 3GC increased amongst Salmonella spp. and S. Typhimurium in the latter part of the period. Conclusions: The total number of iNTS bloodstream infections decreased between 2011-2019. Although the number multidrug resistance (MDR) S. Typhimurium and S. Enteritidis isolates has fallen, the number of MDR isolates of other Salmonella spp. has increased, including 3GC isolates.

Aims:Acinetobacter baumannii has become an important nosocomial pathogen that causes invasive infections. We conducted a retrospective study to evaluate the risk factors for mortality due to A. baumannii bacteremia in children. Materials and Methods: We reviewed data from Seoul National University Children's Hospital from 2002 to 2013 for children with A. baumannii bacteremia, including age, gender, underlying disease, associated site of infection, duration of hospitalization, presence of neutropenia, and antibiotic susceptibility data. The outcome measures were the 7- and 30-day mortality rates. Results: Among 74 A. baumannii bacteremia cases, 35.1% were carbapenem nonsusceptible. Common comorbidities were malignancy or hematologic diseases (28.4%), followed by gastrointestinal/hepatobiliary diseases (21.6%). A total of 47.3% of patients had isolated bacteremia, and in 33.8% of patients, pneumonia accompanied bacteremia. The mortality rates were 18.9% at 7 days and 35.1% at 30 days. The significant associated factors for 30-day mortality were carbapenem nonsusceptibility (adjusted hazard ratio [aHR]: 1.28, 95% confidence interval [CI]: 1.10–11.82, p = 0.034), neutropenia (aHR: 1.68, 95% CI: 1.60–18.03, p = 0.007), and prior intensive care unit (ICU) admission (aHR: 1.15, 95% CI: 1.03–9.73, p = 0.045). The mortality rate among neutropenic patients with inappropriate empirical antibiotics was higher than that among patients with appropriate empirical antibiotics (90.1% vs. 33.3%, p = 0.031). Conclusions: We identified carbapenem nonsusceptibility, neutropenia, and prolonged ICU stay as independent risk factors for mortality due to A. baumannii bacteremia in children. An early administration of appropriate antibiotics should be enacted, especially in patients with neutropenia. [ABSTRACT FROM AUTHOR]

Background: Hamad General Hospital (HGH) is the principal provider of dialysis in the state of Qatar, comprising a total of four facilities in different cities. Infection rates in dialysis patients are increasingly used as a surrogate marker for measuring patient safety and quality of healthcare. These infections are associated with substantial morbidity, mortality, and excess healthcare costs. We observed an elevated rate of hemodialysis catheter-related bloodstream infections (HD-CRBSI) in our outpatient dialysis facilities (1.4/1,000 Central Venous Catheter [CVC] days) in 2011. Our goal was to reduce our HD-CRBSI rate by 80% within a period of four years in HGH ambulatory dialysis facilities. Methods: HD-CRBSIs are defined as the presence of positive blood cultures in a febrile catheter-dependent patient in the absence of alternative sources of infection upon clinical evaluation. The project was led by the HGH quality improvement program director in coordination with a multidisciplinary team (nephrologists, nurses, vascular coordinators, a patient educator, and an infection control team) after implementation of a bundle of infection prevention measures. Results: The rate of HD-CRBSI was reduced from 1.4/1,000 CVC days in 2011 to 0.014 in 2017, achieving a 99% reduction rate (p < 0.001). Conclusions: Strict implementation of our new infection prevention measures bundle is sufficient to significantly reduce HD-CRBSIs. [ABSTRACT FROM AUTHOR]

The factors influencing the virulence of P. aeruginosa in the development of invasive infection remain poorly understood. Here, we investigated the role of the host microenvironment in shaping pathogen virulence and investigated the mechanisms involved. Comparing seven paired genetically indistinguishable clinical bloodstream and peripheral isolates of P. aeruginosa, we demonstrate that isolates derived from bloodstream infections are more virulent than their peripheral counterparts (p = 0.025). Bloodstream and peripheral isolates elicited similar NF-kB responses in a THP-1 monocyte NF-kappaB reporter cell line implicating similar immunogenicity. Proteomic analysis by mass spectrometry identified multiple virulence and virulence-related factors including LecA and RpoN in significantly greater abundance in the bacterial supernatant from the bloodstream isolate in comparison to that from the corresponding peripheral isolate. Investigation by qPCR revealed that control of expression of these virulence factors was not due to altered levels of transcription. Based on these data, we hypothesize a post-transcriptional mechanism of virulence regulation in P. aeruginosa bloodstream infections influenced by surrounding microenvironmental conditions.

The factors influencing the virulence of P. aeruginosa in the development of invasive infection remain poorly understood. Here, we investigated the role of the host microenvironment in shaping pathogen virulence and investigated the mechanisms involved. Comparing seven paired genetically indistinguishable clinical bloodstream and peripheral isolates of P. aeruginosa , we demonstrate that isolates derived from bloodstream infections are more virulent than their peripheral counterparts (p = 0.025). Bloodstream and peripheral isolates elicited similar NF-kB responses in a THP-1 monocyte NF-kappaB reporter cell line implicating similar immunogenicity. Proteomic analysis by mass spectrometry identified multiple virulence and virulence-related factors including LecA and RpoN in significantly greater abundance in the bacterial supernatant from the bloodstream isolate in comparison to that from the corresponding peripheral isolate. Investigation by qPCR revealed that control of expression of these virulence factors was not due to altered levels of transcription. Based on these data, we hypothesize a post-transcriptional mechanism of virulence regulation in P. aeruginosa bloodstream infections influenced by surrounding microenvironmental conditions. [ABSTRACT FROM AUTHOR]

Background: Patients with chronic renal failure who require haemodialysis are at high risk for infections.Aim: To determine the burden of bloodstream and local access-related infections and the prescribing patterns for intravenous antibiotics in Australian haemodialysis outpatients.Methods: A surveillance network was established following stakeholder consultation, with voluntary participation by haemodialysis centres and data collation by the Victorian Healthcare Associated Infection Surveillance System Coordinating Centre. Definitions for infection and intravenous antimicrobial starts were based upon methods employed by the Centers for Disease Control and Prevention. Longitudinal mixed-effects Poisson regression was used to model time-trends for the period 2008-2015.Findings: Forty-eight of 78 Victorian dialysis centres participated in the network, with 3449 events reported over 78,826 patient-months. Rates of bloodstream infection, local infection and intravenous antimicrobial starts were much higher for patients with tunnelled central lines (2.60, 1.41, and 3.37 per 100 patient-months, respectively), compared to those with arteriovenous fistulae (0.27, 0.23, and 0.73 per 100 patient-months, respectively) and arteriovenous grafts (0.76, 1.08, 1.50 per 100 patient-months, respectively). Staphylococcus aureus was the most frequent pathogen, with meticillin-resistant isolates (MRSA) responsible for 14.0%. Access-related infections diminished significantly across all vascular-access modalities over time. Vancomycin contributed nearly half of all antimicrobial starts consistently throughout the study period.Conclusion: Risk for bloodstream and local access-related infections is highest in Australian haemodialysis patients with tunnelled central lines. S. aureus is the most frequent cause of infection, with a low incidence of MRSA. Future programmes should evaluate infection prevention practices and appropriateness of antibiotic prescribing in this population. [ABSTRACT FROM AUTHOR]

Data on catheter-related bloodstream infection (CRBSI) in cubital artery access are scarce. Thus, the objective of this study was to compare the incidence of CRBSI in a large series of patients with femoral or cubital artery catheters. We found 11 events of CRBSI in 1085 femoral artery catheters during 6497 days and none in 449 cubital artery catheters during 2709 days. Poisson regression analysis showed a higher incidence of CRBSI in femoral than in cubital artery site access (1.69 vs 0 CRBSI events per 1000 catheter-days; odds ratio 6.41, 95% confidence interval 1.05-infinite; p == 0.02). In conclusion, according to the results of our observational study, cubital artery access could have a lower risk of CRBSI than femoral artery access. However the development of randomized controlled trials is necessary before this conclusion can be definitively established. In addition, it is necessary to consider other potential mechanical complications when decision-making. [ABSTRACT FROM AUTHOR]

Aim. The purpose of this study was to evaluate in vitro differences of colony forming units (CFUs), of four different bacteria (Staphylococcus epidermidis, Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli), over 4 days, using bovine blood, in five intravenous needleless connectors (three negative, one positive, one zero). Background. Availability of colony forming units creates a definitive environment for bloodstream infections and occlusions. Protection of the intraluminal pathway is one important way to help eliminate occlusions and catheter-related bloodstream infections and utilization of best available product(s) will aid in best patient outcomes. Methods. Five different connectors evaluated in 2009 by an independent laboratory for in vitro differences about colony forming units of four different organisms over 4 days. Results. The Q-Syte™ performed poorly on all organisms (P < 0.0001). The MaxPlus® Clear and MicroCLAVE® fluctuated between high colony forming units (28.15 & 56.55 respectively) and zero colony forming units. The TKO™Clave® stayed increased (high of 50.8 colony forming units). The RyMed-5001® performed the best with very low colony forming units (2.25 CFUs to zero). Conclusions. Non-antimicrobial connectors differ on colony forming unit counts in vitro for four types of bacteria. Connectors with most colony forming units to least colony forming units included the Q-Syte™, TKO™Clave®, MicroCLAVE®, MaxPlus® Clear and RyMed-5001®. Connectors are one statistically significant variable (50%) in the development of occlusions and infections. Staff nurses, managers, infection control specialists and vascular access specialists in all settings need to use technologies that invoke the least patient harm. The RyMed-5001® connector best protects the intraluminal pathway from bacteria compared with four other commonly used connectors in vitro. [ABSTRACT FROM AUTHOR]

Abstract: The use of biomarkers provides a novel approach to diagnosing infection, its severity and treatment response. Biomarkers, especially procalcitonin and, to a lesser extent, C-reactive protein and interleukin 8, can improve the diagnostic and prognostic assessment of bloodstream infections. Both strengths and weaknesses of biomarkers must be recognized for rational and safe use in clinical settings. Cut-off ranges must be chosen within the specific clinical context. Ultrasensitive assays for procalcitonin, capable of measuring low levels in healthy individuals, may help to identify even ‘subclinical’ inflammatory states before the development of clinically evident sepsis. For immunocompromised patients, the use of biomarkers could lead to an earlier and more targeted antimicrobial therapy for patients at risk of sepsis, whereas those patients with viral illness or a non-infectious aetiology of inflammation who maintain low levels of procalcitonin over time can be withheld from antibiotic exposure. The time has arrived to move beyond the observational reporting of ‘promising’ biomarkers. Specific cut-off ranges must be proposed and intervention studies conducted to tackle the existing vicious cycle of diagnostic uncertainty, antibiotic overuse and emerging multi-resistance. [Copyright &y& Elsevier]

Summary: Introduction: Klebsiella pneumoniae is of high prevalence in hospital infections, mainly in bloodstream infections (BSI), and some produce extended-spectrum β-lactamase (ESBL). For hospitals with a high prevalence of strains producing this enzyme, there is no reference material to show whether the use of the E-test method for their detection, which can be quite expensive, is actually required. Objective: To evaluate the cost-benefit of the disk diffusion and E-test methods for the detection of ESBL-producing K. pneumoniae strains in hospitals where a high prevalence of this resistance mechanism in BSI is found. Methods: One hundred and eight patients with K. pneumoniae BSI were evaluated retrospectively. ESBL-producing strains were identified by the disk diffusion method and by the E-test method. We estimated the costs of both diagnostic methods based on antimicrobial therapy adequacy. Results: Fifty-two percent of K. pneumoniae infections were due to ESBL-producing strains. The disk diffusion method yielded a positive predictive value (PPV) of 94.7% (95% CI: 88.9–100%) and a negative predictive value (NPV) of 96.1% (CI 95%: 90.8–101.4%) in relation to the E-test. We evaluated cost-effectiveness, i.e., we analyzed the cost of both E-test and disk diffusion methods with carbapenem and cephalosporins, and found that the use of the disk diffusion method accounts for approximately US$3300. Conclusions: In hospitals with a high prevalence of ESBL-producing strains, the disk diffusion method can be used to detect ESBL-producing K. pneumoniae without compromising the clinical progression of patients with BSI. The E-test showed higher accuracy but this method was more expensive than the disk diffusion method. However, the use of the E-test method was demonstrated to be more cost-effective, as we evaluated cost based on antimicrobial therapy adequacy. [Copyright &y& Elsevier]

Abstract: Background: We report the aetiology and outcome of bloodstream infections (BSI) occurring at two regional cystic fibrosis (CF) centres (one adult, one paediatric) between 1998 and 2006. Methods: A retrospective analysis of all positive blood cultures during the study period was performed. Results: During the study period 1691 blood culture sets were taken. Fifty-seven clinically significant episodes of BSI in 48 people with CF (36 adult, 12 paediatric) were identified, along with 28 other episodes considered to be contamination or not clinically significant. The most common BSIs were caused by coagulase-negative staphylococci (13) Candida spp (10), and Stenotrophomonas maltophilia (8). The majority (82%) of significant BSIs were considered to originate from totally-implantable vascular access devices (TIVADs); only 9% were attributed to the lower respiratory tract. The TIVAD was removed in two-thirds of cases of TIVAD-associated BSI. There were three deaths (60% of cases) attributable to BSI originating from the lower respiratory tract but no deaths attributable to TIVAD-associated BSI. Conclusion: Most significant BSIs in patients with CF originate from TIVADs. Targeted antimicrobial therapy and appropriate early device removal is associated with good clinical outcome. BSI originating from the lower respiratory tract is associated with poor clinical outcome. [Copyright &y& Elsevier]

The authors reflect on a peer review about central catheter-associated infections in critical care medicine. They emphasizes the importance of developing standards of protocol for the study of central catheter-associated infections. They stress that the peer review concur with the Centers for Disease Control and Prevention (CDC) guidelines concerning the preference of the subclavian vein as the site for central venous catheterization.

Early identification of an outbreak is one of the main advantages of routine epidemiological surveillance. Enterococcus spp. used to be regarded as microorganisms of low pathogenicity, because they are part of the normal microbial flora of the gastrointestinal and genitourinary tract. Recently, they have emerged as important pathogenic agents, sometimes causing infections with high mortality rates. We studied a clustering of primary bloodstream infections caused by Enterococcus faecalis in a cardiology hospital neonatal intensive care unit (NICU). Four cases of primary bloodstream infection by E. faecalis were detected from April 15 to May 13, 2004, during active infection surveillance. The isolates were sensitive to glycopeptides. Some aspects of the management of these patients, including the date of insertion and placement of a central venous catheter, prescription of a specific medication, contiguity of beds, personnel attending the patients, and occurrence of diarrhea were analyzed to look for factors that might affect the spread of the microorganisms. Measures taken to hamper the spread included contact precautions throughout the unit, cleansing and disinfection of equipment and surfaces, bathing children with 2% chlorhexidine-gluconate-containing soap, professional reeducation, and reinforcement of all measures to prevent infections. We suggest that there is a need to re-evaluate preventive infection measures and to review the strategies aimed at decreasing the nosocomial infection rate in the NICU.