Journal of Clinical Microbiology最新文献

Reduced susceptibility to antifungals is common among members of genera Scedosporium and Lomentospora, with optimal treatments still not fully defined. In vitro antifungal susceptibility results and clinical data do not comprehensively account for the advent of new Scedosporium species identified by molecular phylogenetics. Using Clinical and Laboratory Standards Institute (CLSI) methodology, we tested a total of 103 clinical isolates obtained from patients at the NIH Clinical Center. The most frequent species were Scedosporium apiospermum (63%) and Scedosporium boydii (11%), followed by Lomentospora prolificans (7%). The novel antifungal olorofim showed the lowest MICs against all Scedosporium spp. and L. prolificans, followed by micafungin. Among the triazoles, voriconazole showed lower MICs against Scedosporium spp. Amphotericin B and posaconazole demonstrated species-specific and inter-species variable activity. Itraconazole, isavuconazole, and terbinafine had higher MIC values against Scedosporium spp. and L. prolificans. Clinical data were retrospectively reviewed for 90 isolates, of which nine patients (28 isolates) had active disease/infection and received antifungal treatment that included voriconazole or posaconazole. Five of these patients (56%) died, while three patients (33%) with chronic granulomatous disease were cured following hematopoietic cell transplantation. In 24 patients (62 isolates), the presence of the fungus was considered airway colonization. In conclusion, our data support the existence of species-specific and inter-species differences in the antifungal susceptibility patterns among members of genera Scedosporium and L. prolificans. The novel investigational antifungal olorofim may be a promising therapy. Our clinical data suggest that host status and administration of antifungal therapy most effective for each Scedosporium species complex are important determinants of outcomes.IMPORTANCEUnderstanding the epidemiology and clinical spectrum of infections caused by Scedosporium species complex and Lomentospora prolificans is integral to improving outcomes, particularly in severely ill and immunocompromised patients. In vitro antifungal susceptibility testing can provide an estimate of antifungal activity against fungal pathogens. Our study showed that species-specific and inter-species differences exist in the distribution of antifungal susceptibility patterns between Scedosporium and L. prolificans. Our clinical data also highlight that host status, along with effective antifungal therapy, plays a crucial role in determining treatment outcomes.

Tuberculosis (TB) remains a global public health problem. The determination of tuberculosis infection (TBI) using interferon-gamma release assay has now been used widely. We aim to evaluate the positivity rates of Standard E TB-Feron enzyme-linked immunosorbent assay (TB-Feron ELISA) and Standard F TB-Feron fluorescent immunoassay (TB-Feron FIA) and their agreement with QuantiFERON-TB Gold Plus (QFT-Plus) among TB high-risk populations in Bandung City, Indonesia. We conducted a cross-sectional study, including people with a high risk of acquiring TB. We screened subjects for TB symptoms and offered chest X-ray (CXR). Anyone with cough or CXR suggestive of TB was asked to give sputum samples for GeneXpert MTB/RIF Ultra test. The positivity rates and corresponding 95% confidence intervals (CI) were calculated among patients with bacteriologically confirmed TB and among patients with no evidence of TB, no history of TB, and no known contact with TB patient (low risk of TBI). The agreement with QFT-Plus was calculated using Cohen's κ score. We enrolled 527 subjects, and the proportion of positive results among bacteriologically confirmed TB patients were 8 (53.3%; 95% CI 26.6-78.7), 9 (60.0%, 95% CI 32.3-83.7), and 10 (66.7%, 95% CI 38.4-88.8) by TB-Feron FIA, TB-Feron ELISA and QFT-Plus. The agreement between TB-Feron FIA and QFT-Plus among all subjects was similar to that of TB-Feron ELISA and QFT-Plus (84.1%, κ = 0.66, 95% CI 0.59-0.72). TB-Feron FIA and TB-Feron ELISA showed an acceptable clinical performance compared with QFT-Plus. These tests are useful alternatives for detecting TB infection.IMPORTANCEThis study evaluates the performance of two alternative interferon-gamma release assays, Standard E TB-Feron enzyme-linked immunosorbent assay and Standard F TB-Feron fluorescent immunoassay, for diagnosing tuberculosis infection (TBI) among high-risk populations in Bandung, Indonesia. Both assays demonstrated comparable clinical performance to the widely used QuantiFERON-TB Gold Plus (QFT-Plus). Given the global burden of tuberculosis, particularly in resource-limited settings, these findings suggest that the TB-Feron assays could serve as reliable alternatives to QFT-Plus for TBI detection. This research highlights the potential for these assays to improve tuberculosis diagnosis, offering a more accessible and efficient screening tool, especially for high-risk populations, and supporting broader tuberculosis surveillance.

This study evaluated thin-layer agar (TLA) as a faster alternative for both indirect minimum inhibitory concentration (MIC) determination of bedaquiline (BDQ) from culture isolates and direct drug-susceptibility testing (DST) from sputum samples. Indirect BDQ-MIC results from TLA were compared to the established 7H11 solid DST. Direct-TLA-DST performance was assessed using 143 baseline sputum samples from rifampicin-resistant TB cases. Direct-TLA tested susceptibility to rifampicin, isoniazid, levofloxacin, and BDQ, with results compared to Löwenstein-Jensen (LJ) and MGIT. For indirect BDQ-MIC determination, TLA accurately identified H37Rv MICs within the WHO control range (0.015-0.12μg/mL). Optimal results were obtained with standard incubation and day 7 reading of the plates. TLA correctly classified all wild-type clinical strains as BDQ-susceptible and detected 9 out of 10 BDQ-resistant strains with elevated MICs. Direct-TLA-DST detected MTB in 53.8% of samples, compared to 55.9% on LJ and 69.4% in MGIT. Uninterpretable results due to contamination or medium drying were low (4.9%). The median time to result was 15 days for smear-positive and 22 days for smear-negative samples, faster than WHO-endorsed methods. Sensitivity was 100% for rifampicin and 87.8% for isoniazid, with a specificity of 100% for all drugs except isoniazid (96.2%). No BDQ nor levofloxacin resistance was detected, thus direct TLA sensitivity could not be assessed. In conclusion, direct-TLA-DST offers a reliable and faster alternative to conventional DST methods for BDQ and other anti-TB drugs. Essentially, this technique can be operated at BioSafety Level 2, allowing decentralization of pDST for managing drug-resistant TB in settings with limited laboratory infrastructure.

Importance: This paper addresses the critical need for faster direct drug-susceptibility testing (DST) on sputum, especially for bedaquiline (BDQ), which is a key drug in treating drug-resistant TB. Currently, there is a lack of rapid, reliable methods for direct BDQ testing from sputum samples, limiting timely and accurate treatment decisions and monitoring. By demonstrating the potential of thin-layer agar (TLA) for direct BDQ-MIC determination, this study offers a promising solution that could significantly improve patient care.

Escherichia coli pathotypes are enteric pathogens detected in gastrointestinal multiplex polymerase chain reaction (mPCR), with controversial clinical relevance. Our study aimed to describe clinical features and therapeutic decisions associated with E. coli detections in gastrointestinal mPCR. Children with positive mPCR for enteroaggregative (EAEC), enteropathogenic (EPEC), enterotoxigenic (ETEC), Shiga toxin-producing E. coli (STEC), and enteroinvasive E. coli (EIEC)/Shigella identified in two pediatric hospitals over 18 months (2020-2021) were included. We described the frequency of E. coli detection and subsequent modifications in antibiotic strategies. Among the 2,471 mPCRs performed, 338 (14%) tested positive for at least one E. coli pathotype. The patient's mean age was 4.2 years, with 95% experiencing gastrointestinal symptoms. Clinical presentation was generally comparable between E. coli pathotypes. A recent travel abroad was reported in 68/338 (20%) cases and was mainly observed in EIEC/Shigella infections. An E. coli was detected alone in 177/338 (52%) cases and with another virus, bacteria, or parasite in 161 (48%) cases. Multiple enteric pathogens were mainly detected with ETEC (n = 24/26, 92%) and EAEC (n = 82/121, 68%) detections. Antibiotic therapy was prescribed in 136/338 (40%) cases, with initiation based on mPCR results in 69/338 (20%). No antibiotic therapy was discontinued following positive mPCR results. Among the 69 initiations, 31 were deemed inappropriate after retrospective chart review. E. coli detection with mPCR tests may lead to inappropriate antibiotic initiation. Caution is advised when interpreting results from gastrointestinal mPCRs in children, as clinicians may be unaware of their often unclear or irrelevant clinical significance.IMPORTANCEEscherichia coli pathotypes are increasingly detected through the widely used syndromic gastrointestinal multiplex PCR panels. However, their clinical significance and impact on antibiotic therapy in children remain uncertain. This study describes the clinical and microbiological characteristics associated with E. coli detections, as well as the subsequent modifications in antibiotic strategies. It highlights the frequent detection of E. coli pathotypes, often in association with other enteric pathogens, and reveals that nearly half of the antibiotics prescribed following these results were deemed inappropriate. These results underscore the need to enhance clinicians' interpretation of E. coli-positive results and reassess treatment strategies to optimize patient care.

The World Health Organization (WHO) 2030 roadmap for schistosomiasis calls for development of highly sensitive and specific diagnostic tools to continue and sustain progress towards elimination. Serological assays are excellent for sensitive detection of primary schistosome infections and for schistosomiasis surveillance in near- and post-elimination settings. To develop accurate assay formats, it is necessary to identify defined antibody targets with low cross-reactivity and potential for standardized production. Here we aim to identify such target(s) with focus on defined schistosome glycan antigens. Target identification was performed by assessing antibody responses in well-characterized cross-sectional and cohort sample sets (n = 366 individuals) on tailor-made antigen microarrays. IgM and IgG binding to candidate diagnostic targets was measured for serum/plasma samples from controlled human schistosome infection models, schistosome-infected travelers, soil-transmitted helminth-infected individuals, and non-infected individuals. We found that antibodies to a schistosome gut-associated glycan, the circulating anodic antigen (CAA), identify schistosome infection with high sensitivity (IgM ≥100%, IgG ≥97%) and specificity (IgM ≥93%, IgG ≥97%) in the test samples. Infection dose affected timing of anti-CAA antibody isotype switch. Furthermore, we demonstrate that other non-specific glycan epitopes in crude schistosome cercarial and egg antigen preparations can contribute to generation of false schistosomiasis positives, which is relevant for current serological assays based on these antigen mixtures. In conclusion, CAA is an excellent single glycan antigen target for development of highly sensitive and specific tools for schistosomiasis serology with use cases for travelers and surveillance in near- and post-elimination settings, as well as emerging transmission zones.

Importance: The WHO 2030 roadmap deems diagnostics developments for schistosomiasis critically needed. Here we present identification of an antibody target with superior performance compared to traditionally used crude antigens in schistosomiasis serology. Access to unique controlled human infection model samples, traveler samples, and negative controls enabled this discovery, which forms the basis for development of new diagnostic tools urgently needed in travel medicine, surveillance in emerging transmission zones driven by climate change, and in pre- and post-elimination scenarios.