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BackgroundIdentification of the opportunistic fungus Pneumocystis jirovecii in respiratory specimens presents challenges, particularly in differentiating between colonization and active infection. The present study assessed a probe-based real time PCR (qPCR) diagnostic effectiveness in patients with diverse underlying conditions, particularly those with COVID-19 and pulmonary insufficiency.MethodsTo set up the qPCR, clinical samples from 281 patients with respiratory ailments were tested. Subsequently, a descriptive study was conducted on 112 patients with pulmonary insufficiency with and without COVID-19 suspected of P. jirovecii infection. All specimens were subjected to DNA extraction followed by nested PCR and qPCR targeting the mitochondrial large subunit (mtLSU)-rRNA gene.ResultsBased on nested PCR and qPCR, P. jirovecii was identified in 40 out of 281 patients, with slight variations in positive samples observed across dilutions. Three patients who tested positive in nested PCR yielded negative results in probe-based qPCR. Conversely, three patients who tested positive in probe-based qPCR yielded negative results in nested PCR. Considering nested PCR as the golden standard, probe-based qPCR demonstrated good diagnostic performance, with 92.5% sensitivity and 98.7% specificity. Based on cycle threshold (Ct) values, the positive cases were categorized: ≤32 as infection, >35 as colonization, and a grey zone between these values (32 < X ≤ 35). The analysis of 112 PCP-suspected patients revealed a prevalence ranging from 6.25% (nested PCR) to 7% (probe-based qPCR).ConclusionsThis study suggested Ct values to differentiate Pneumocystis pneumonia/colonization in immunocompromised patients. To further augment the diagnostic sensitivity, it is recommended to integrate qPCR results with clinical parameters and biomarkers to offer a more precise understanding of Pneumocystis-related conditions.

IntroductionAlthough the existence of Candida species in the respiratory tract is often considered commensal, it is crucial to recognize the significance of Candida colonization in immunocompromised or COVID-19 patients. The emergence of Candida auris as an emerging pathogen further emphasizes the importance of monitoring yeast infection/colonization, particularly in COVID-19 patients.MethodsIn this study, respiratory samples mainly from COVID-19 patients, primarily those suspected of having a fungal infection, were cultured on Sabouraud dextrose agar plates and the yeast colonies were identified using a two-step multiplex PCR method. The samples suspected of C. auris underwent specific nested PCR followed by sequence analysis.ResultsA total of 199 respiratory samples were collected from 73 women and 126 men, ranging in age from 1.6 to 88 years. Among the patients, 141 had COVID-19, 32 had cancer, 5 were hospitalized in ICU, 2 had chronic obstructive pulmonary disease)COPD(, and others were patients with combination diseases. From these samples, a total of 334 yeast strains were identified. C. albicans (n=132, 39.52%) was the most common species, followed by C. tropicalis (n=67, 20%), C. glabrata (n=56, 16.76%), C. krusei (n=18, 5.4%), C. parapsilosis (n=17, 5.08%), Saccharomyces cerevisiae (n=10, 3%), C. kefyr (n=9, 2.6%), C. dubliniensis (n=7, 2.1%), C. lusitaniae (n=5, 1.5%), C. auris (n=3, 0.9%), C. guilliermondii (n=2, 0.6%), C. rugosa (n=1, 0.3%), C. intermedia (n=1, 0.3%), and Trichosporon spp. (n=1, 0.3%). C. auris was detected in a patient in ICU and two COVID-19 patients. While its presence was confirmed through sequence analysis, our extensive efforts to isolate C. auris were unsuccessful.ConclusionWhile C. albicans colonization remains prevalent, our study found no evidence of Candida lung infection. Since the role of Candida colonization in airway secretions remains ambiguous due to limited research, further studies are imperative to shed light on this matter.

Candidemia caused by rare and uncommon Candida species is becoming more prevalent in pediatric healthcare settings, resulting in significant morbidity and mortality. One such species, Candida palmioleophila, is resistant to fluconazole but highly susceptible to echinocandins. Here, we report the first documented case of C. palmioleophila candidemia in Iran that occurred in a male infant with biliary atresia who had been hospitalized for 2 months. The patient’s blood and urine cultures were positive for both yeast and bacterial species. Through DNA sequence analysis, the yeast isolate was identified as C. palmioleophila. In vitro antifungal susceptibility testing of the isolate against amphotericin B, fluconazole, itraconazole, voriconazole, isavuconazole, posaconazole, and nystatin revealed MIC values of 2, 16, 0.25, 0.0625, 0.125, 0.25, and 4 μg/mL, respectively, and minimum effective concentration for caspofungin was 0.031 μg/mL. Despite receiving antibacterial and antifungal therapies, the patient unfortunately expired due to bradycardia and hypoxemia. Proper identification and epidemiological surveillance studies are needed to understand the exact prevalence of these emerging yeast pathogens. Previously reported cases of C. palmioleophila infection, primarily associated with bloodstream infections and catheter-related candidemia, were reviewed.

BackgroundDeveloping more sensitive methods for the diagnosis of echinococcosis is essential. In this study PCR assay for sensitive detection of specific cell-free DNA (cfDNA) of Echinococcus granulosus sensu lato in the sera of the sheep naturally infected with echinococcosis was investigated.MethodsTo extract cfDNA from 35 infected sheep, the modified phenol-chloroform method was used for two different volumes (0.5 and 2 ml) of serum samples. From each extracted sample, two DNA volumes (5 and 10 μl) were amplified using both standard PCR and semi-nested PCR targeting NADH dehydrogenase subunit I.ResultsStandard and semi-nested PCR on 0.5 ml of serum samples detected Echinococcus DNA in 8 and 12 out of 35 sheep, respectively; however, using 2 ml of serum samples, they detected 24 and 27 samples. By increasing the volume of template DNA, the PCRs could detect 29 and 33 out of 35 samples. The results were confirmed by sequencing of randomly selected PCR amplicons and comparing them with GenBank databases.ConclusionsLarger volumes of serum for DNA extraction, greater volumes of DNA template for PCR, and employing a semi-nested PCR protocol, increased the sensitivity of PCR to 95%. This approach can also be applied to the diagnosis of echinococcosis in humans.

Invasive fungal rhinosinusitis (IFRS) is a life-threatening infection that can occur in immunocompromised patients, including those with COVID-19. Although Mucorales and Aspergillus species are the most common causes of IFRS, infections caused by other fungi such as Fusarium are rare. In this report, we present three cases of proven rhinosinusitis fusariosis that occurred during or after COVID-19 infection. The diagnosis was confirmed through microscopy, pathology, and culture, and species identification of the isolates was performed by DNA sequencing the entire ITS1-5.8 rRNA-ITS2 region and translation elongation factor 1-alpha (TEF-1α). Antifungal susceptibility testing was conducted according to CLSI guidelines. The causative agents were identified as Fusarium proliferatum, F. oxysporum + Aspergillus flavus, and F. solani/falciforme. Treatment involved the administration of antifungal medication and endoscopic sinus surgery to remove the affected mucosa, leading to the successful resolution of the infections. However, one patient experienced a recurrence of IFRS caused by A. flavus 15 months later. Early diagnosis and timely medical and surgical treatment are crucial in reducing mortality rates associated with invasive fusariosis. Additionally, the cautious use of corticosteroids in COVID-19 patients is highly recommended.

IntroductionEarly detection of Pneumocystis jirovecii as an opportunistic pathogen that may endanger predisposed persons, including COVID-19 patients, may help to choose the optimal management.MethodsIn this study, 585, including 530 COVID-19 patients, with clinical and radiological evidence of respiratory diseases, were investigated for P. jirovecii screening. Clinical specimens were examined by direct microscopy and PCR, and randomly selected positive PCR products were confirmed through DNA sequence analysis.ResultsThirty-one (5.3%) samples were positive in P. jirovecii-specific nested-PCR, while by direct microscopic tests, Pneumocystis was observed in 22 (3.76%) samples. Males (61.7%) and patients over 50 years old (75.6%) were more commonly affected than others, and malaise and fatigue (84%), and wheezing (75%) were the most common symptoms, followed by fever (40.48%) and dyspnea (39.51%). Among the Pneumocystis-positive patients, three cases had coinfection with Aspergillus fumigatus, A. flavus, and A. niger (each n = 1), as documented by direct microscopy, culture, and species identification by PCR-sequencing.ConclusionPneumocystis pneumonia is still a diagnostic challenge; therefore, additional large-scale studies are needed to clarify the epidemiology of the disease in immunocompromised or COVID-19 patients.

Along with the pandemic COVID-19 spreads, new clinical challenges have emerged in the health care settings, among which there is a high risk of secondary invasive fungal infections with significant mortality. Here, we report a case of invasive fungal rhino orbital sinusitis due to the simultaneous co-infection by Rhizopus oryzae and Lomentospora prolificans, both identified by sequencing, in a 70-year-old Afghanistanian female with COVID-19. The patient was subjected to surgical debridement as well as taking liposomal amphotericin B, voriconazole, and on discharge, her condition was good. As far as we know, this is the first case of co-infection of COVID-19-associated mucormycosis (CAM) and Lomentospora prolificans infection. Multiple fungal co-infections in COVID-19 patients are reviewed.

Abstract Harmless commensal Candida species, especially uncommon and rare ones may rarely cause a serious infection. Candida metapsilosis is a recently described yeast that is phenotypically indistinguishable from Candida parapsilosis and molecular methods are essential for its identification. We report the first case of Candida conjunctivitis due to C. metapsilosis obtained from the eye discharge of a 40‐day‐old girl with congenital heart disease admitted to the cardiac intensive care unit (CICU). The yeast isolate was identified by sequencing the entire ITS1‐5.8 rRNA‐ITS2 region. Antifungal susceptibility testing performed according to the CLSI M27‐A3 showed that the isolate was susceptible to amphotericin B, fluconazole, itraconazole, voriconazole, clotrimazole, nystatin, terbinafine, 5‐fluorocytosine, and caspofungin. Differentiation of the fungal new species allows us the accurate diagnosis and treatment, and a better understanding the microbial epidemiology.

A fatal case of COVID-19-associated mucormycosis (CAM) affected a 40-year-old woman who was initially admitted to our hospital due to a SARS-CoV-2 infection. Her clinical condition worsened, and she finally died because of respiratory failure, hemodynamic instability, and mucormycosis with invasion into the orbit and probably the brain. According to DNA sequence analysis of the fungus isolated from the patient, Apophysomyces variabilis was involved. This is the first published case of CAM and the third case of mucormycosis due to this mold.

Background and Purpose: The taxonomy of Candida is controversial and has undergone changes due to the investigation of the novel species. Candida africana and Candida dubliniensis are new members of C. albicans complex that are currently gaining both clinical and epidemiologic significance. This study reports the prevalence of C. africana among the strains isolated from patients, by using HWP1 gene size polymorphism.Materials and Methods: A total of 235 yeasts confirmed as C. albicans complex based on chromogenic media and ITS-sequencing isolated from various clinical forms of invasive and non-invasive candidiasis mainly candidemia, were re-identified based on HWP1 gene polymorphisms. The Hwp1-PCR amplicons were re-confirmed by sequencing and BLAST analysis.Results: Based on the HWP1 gene size polymorphism, 223 strains were identified as C. albicans (94.89%) from which 7 isolates produced two DNA fragments (850 and 941 bp). C. dubliniensis (n=4, 1.7%), C. africana (n=1, 0.42%) and mix of C. albicans and C. africana (n=7, 2.97%) were also identified. Conclusion: Although C. albicans remains the most common Candida species, C. dubliniensis and C. africana are rarely found among the patient isolates. Due to limited information on the molecular epidemiology of this novel yeast, more studies using molecular methods are recommended.

Background and Purpose: The most common etiological agents of human dermatophytosis in various parts of the world are Trichophyton rubrum, Trichophyton interdigitale, and Epidermophyton floccosum. The main aim of this study was to design and evaluate a simple and straightforward multiplex polymerase chain reaction (PCR)assay for reliable identification/differentiation of these species in clinical isolates.Materials and Methods: The reliable sequences of several molecular targets of dermatophytes species were used to design a multiplex PCR for the identification of common pathogenic dermatophytes. The isolates and clinical specimens examined in this study included seven standard strains of dermatophytes, 101 isolates of dermatophytes and non-dermatophyte molds/yeasts which had already been identified by sequencing or PCR-restriction fragment length polymorphism (RFLP), and 155 clinical samples from patients suspected of cutaneous mycoses.Results: Species-specific primer pairs for T. rubrum and T. interdigitale/T. mentagrophytes were designed based on the sequence data of the translation elongation factor 1-alpha gene, and the primers for E. floccosum targeted the specific sequence of the internal transcribed spacer region (ITS). The multiplex PCR successfully detected T.rubrum, T. interdigitale/T. mentagrophytes, and E. floccosum strains that were identified by sequencing or PCR-RFLP. However, the primer pairs selected for T. interdigitale/T. mentagrophytes cross-reacted with Trichophyton tonsurans. In testing the PCR system directly for clinical samples, the proportion of positive multiplex PCR was higher than positive culture (68.1% vs. 55.4%, respectively).Conclusion: The multiplex assay could detect three common agents out of several causal agents of dermatophytosis, namely T. rubrum, T. interdigitale, and E. floccosum.Therefore, by adding pan-dermatophyte primers it can be used as a comprehensive detection/identification test.

Background: Candida species cause a wide spectrum of disease entities. Candida africana and Candida dubliniensis–members of Candida albicans complex-are currently gaining both clinical and epidemiologic significance. Materials and methods: Totally, 150 pediatric isolates that had previously been identified as C. albicans species complex based on a positive germ tube test were included. The isolates were cultured on CHROMagar Candida medium to ensure their purity and the results of germ tube test. For definitive speciation, PCR amplification and size polymorphism of the hyphal wall protein 1 (HWP1) gene was used. The results of HWP1-PCR were confirmed by sequencing the amplified fragments for randomly selected isolates of C. africana and C. dubliniensis. Results: All 150 isolates included in this study were reconfirmed as C. albicans complex on chromogenic media. Based on the HWP1 gene size polymorphism, 141 (94%) isolates were identified as C. albicans, 2 (1.33%) as C. africana, and 1 (0.67%) as C. dubliniensis. The remaining 6 (4%) C. albicans complex isolates were a mix of C. albicans and C. africana. All isolates of C. africana and C. dubliniensis have been recovered from cases of candiduria. Conclusion: C. africana, either alone or mixed with C. albicans, could be a cause of candiduria among pediatric patients and should not be ignored.

Background: There is an increasing incidence of life-threatening systemic mycoses, specifically fulminant infections by the Candida species in hospitalised patients and in those who are immunocompromised. Management of the limited number of antifungal drugs currently available requires the identification of infections containing drug-resistant isolates. Objectives: The aim of this study was to identify the non-albicans Candida species as azole-resistant fungi, isolated from sputum and bronchoalveolar lavage specimens of hospitalised cases. Methods: The subjects included hospital-acquired infection (HAI) cases, with a primary diagnosis using a direct microscopic examination, performed for the detection of probable fungi. The molecular tests of PCR-restriction fragment length polymorphism (RFLP) and real-time PCR were performed to confirm the identity and molecular typing of the Candida isolates. Antifungal susceptibility testing (AFST), by the Clinical and Laboratory Standards Institute (CLSI) broth microdilution (BMD) minimum inhibitory concentration (MIC) (M27-A2) method, was performed on the hospital-isolated Candida species. Results: During 24 months, from August 2014 to September 2016, a total of 198 samples were obtained from cases with proven HAI. The results of experimental studies on the specimens showed 93 (47%) positive cases for a fungal or bacterial infection, of which 54 (58%) had a fungal infection. It was hypothesised that all of the isolated organisms were causative agents of the HAI. Conclusions: The results showed that the medium CHROMagar™ Candida is an accessible and easy-to-use method for the identification of infection, but not as accurate and reliable as PCR-RFLP and real-time PCR methods. Results also showed decreasing susceptibility to azoles (itraconazole in this study) of the Candida species.

Background: Tracheoesophageal voice prostheses (TVPs) have been the gold standard in rehabilitation, after laryngectomy, producing faster and premier voicing towards esophageal speech. Fungal colonization shortens the device’s lifetime and leads to prosthesis dysfunction, leakage, and subsequent respiratory infection. Therefore, in the current study, we aimed to investigate the fungal colonization patterns and to propose prophylactic measures that shall increase the longevity of voice prosthesis. Methods: Failed TVPs were removed - due to leakage and/or aspiration - from 66 post laryngectomy patients and examined. They were referred to Amiralam and Rasoul Hospital, the main centers of Ear, Nose, and Throat in Tehran, Iran from April 2018 to January 2020. Fungal colonization patterns were assessed using DNA sequencing techniques. Furthermore, the susceptibility to fluconazole, amphotericin B, nystatin, and white vinegar was evaluated according to the Clinical and Laboratory Standards Institute (CLSI) guidelines. Results: Resident fungal species from the upper airways colonized all the 66 TVPs (100%). Diabetes (31%) and smoking (98%) were the predominant underlying disease and predisposing factors, respectively. Among the 79 fungal agents isolated from the 66 TVPs, Candida glabrata (n=25, 31.7%) was the most common. A significant reduction in minimum inhibitory concentration (MIC) values were observed for white vinegar when used alone (P

Background: Bovine coronaviruses (BCoVs) are zoonotic diseases that result in substantial economic losses due to mortality, impaired growth, and increased medication expenses in large animals. These viruses pose a risk to children who live beside infected animal, as they can cause diarrhea. This study was dedicated to molecular and antigen detections and phylogenetic and immunoinformatics analysis of zoonotic coronavirus (CoV) in Iran. Materials and Methods: A total of 77 diarrheic samples were collected from Holstein dairy herds in selected provinces of Iran. Samples were tested by capture antibody enzyme-linked immunosorbent assay (ELISA) to detect CoV and reverse transcriptase–polymerase chain reaction (RT–PCR) for verification of detection and also genotyping of spike glycoprotein in CoV-positive samples. After statistical analysis, nucleotide sequence alignment, and nucleotide and protein phylogenetic tree construction, the centralized sequence for vaccine strains was obtained using computationally optimized broadly reactive antigen (COBRA)'s center-of-the-tree (COT) method. Results: Twenty-two (28.5%) and eight (10.3%) of 77 samples were positive according to RT–PCR and ELISA, respectively. (Basic Local Alignment Search Tool) BLAST and phylogenetic analysis revealed that most similar sequences to the Iranian CoV sequence were for European countries. Furthermore, there were strong correlations to other CoVs in humans and wild and domesticated animals. As CoV has variable COT, the most recent strains and COBRA vaccine strains were obtained. Conclusion: Based on the high prevalence of this viral disease in calves and its economic impact on the breeding industry, as well as the potential transmission to humans and correlation with World Health Organization (WHO) One Health approach guidelines, the study emphasizes the importance of implementing preventive strategies such as animal vaccination.

BackgroundConsidering the importance of differential diagnosis of infectious otitis externa (OE), a stepwise PCR-based assay using universal and genus- or species-specific primers for the detection/identification of the most prevalent bacterial and fungal OE was developed and evaluated on the ear aspiration specimens of clinically suspected patients.Methods and MaterialsA total of 120 ear aspiration specimens with otomycosis suspicion were subjected to manual DNA extraction using phenol–chloroform extraction after tissue digestion with a lysis buffer. The multiplex PCR was initially performed using pan-fungal and bacterial homemade primers. Pseudomonas and Staphylococcus specific primers were simultaneously used in one reaction mixture to identify the bacterial genera. Furthermore, for the identification of fungal agents, Candida species-specific multiplex primers targeting the most clinically important Candida species causing OE (i.e., C. albicans, C. parapsilosis, and C. auris), as well as Aspergillus related multiplex PCR identifying the most prevalent Aspergillus species were used in two separate reaction mixtures. All the results of multiplex PCR were interpreted based on the amplicon size.ResultsThe overall multiplex PCR-based detection rate of bacterial (n = 88; 73.3%) and fungal (n = 97; 81%) OE was documented to be 100% along with and complete consistency with the results of direct examination and Giemsa staining. Double amplicon bands of bacterial and fungal pathogens were evidenced in 76 specimens (63.3%). Moreover, the positivity rate of pan-fungal PCR was higher than that of the culture result. Out of 88 pan-bacterial positive PCR specimens, 66 and 47 ones were positive for Staphylococcus and Pseudomonas, respectively. In addition, 30 samples exhibited mixed infection of both, and five specimens remained negative. Out of 97 pan-fungal positive PCR specimens, 67 and 51 ones contained Candida and Aspergillus species, respectively. It should be noted that dual amplicon bands of Candida and Aspergillus-related multiplex PCR were yielded in 30 specimens.ConclusionThe stepwise multiplex PCR assay proved to be more sensitive, more rapid, as well as less cumbersome in detection and identification of fungal and bacterial OE, compared to culture.

Background: Early and cost-effective diagnosis and monitoring of the infection caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are critically important to anticipate and control the disease. We aimed to set up a SYBR Green-based one-step real-time polymerase chain reaction (PCR) as a lower-cost alternative method to detect the virus. Materials and Methods: An in-house SYBR Green-based PCR assay targeting the envelope (E) and RNA-dependent RNA polymerase (RdRp) genes, was set up to diagnose the infection, and was compared with the reference probe-based PCR method. Results: When the commercial probe-based assay was considered as the reference method, SYBR Green-based PCR had a slightly lower sensitivity (81.98% and 86.25% for E and RdRp targets, respectively) and a good specificity (100% and 94.44% for E and RdRp targets, respectively). For both gene targets, three different melting temperature (Tm) patterns were found in the PCRs of the nasopharyngeal/oropharyngeal swab samples, but no size polymorphism was seen in agarose gel electrophoresis. Conclusion: Further studies to improvement of the assay are needed to make it an inexpensive and reliable tool for the diagnosis of COVID-19.