European Journal of Clinical Microbiology & Infectious Diseases最新文献

The genomic comparison of two Klebsiella michiganensis clinical isolates recovered from the same patient, one resistant to piperacillin-tazobactam and intermediate to cefotaxime, the other resistant to ceftazidime but susceptible to piperacillin-tazobactam, revealed one mutation in the bla_OXY-1-24 gene accounting for a L169M substitution in the Ω loop. Cloning experiment in Escherichia coli demonstrated the contribution of this mutation to the hydrolysis spectrum extension towards ceftazidime and cefepime, whereas the resistance to piperacillin-tazobactam was reduced. To the best of our knowledge, this study shows for the first time that ceftazidime resistance can occur in vivo from OXY-1 precursor by structural alteration.

Purpose: Haemophilus influenzae (HINF), primarily non-typeable H. influenzae: (NTHi), is an important cause of neonatal sepsis and meningitis. The goal of this study was to investigate the point prevalence of HINF vaginal-rectal carriage in pregnant women, which could impact neonatal health.

Methods: Simulated vaginal-rectal swabs were cultured and tested to establish optimal recovery methods for HINF. These methods were then applied to vaginal-rectal swabs from a prospective cohort of pregnant women (n = 300) undergoing routine Group B Streptococcus: (GBS) screening. Both culture and PCR were used for detection of HINF. Subject demographics, reproductive history, and genitourinary test results were documented. A retrospective surveillance study was conducted to determine incidence of invasive neonatal HINF infections from 7/1/2017-6/30/2023.

Results: HINF was recovered from 42/42 (100%) simulated vaginal-rectal swabs at 2-45 CFU/plate via direct plating onto chocolate and chocolate + bacitracin agar. HINF was rarely recovered following LIM broth enrichment at 0-75 CFU/plate in 1/42 (2.4%) simulated swabs, but was recovered from BHI/Fildes broth enrichment in 22/42 (52%) specimens at high abundance (> 100 CFU/plate). Among pregnant women prospectively screened for HINF, the median age was 29 (IQR, 24-33) years and gestational age was 36 (IQR, 34-36) weeks. HINF was recovered in 1 of 300 prospective specimens by culture but 0/100 by PCR. A six-year retrospective analysis showed there were seven total cases of neonatal sepsis and majority of HINF was isolated from respiratory specimens followed by blood/CSF overall.

Conclusion: This study established a sensitive culture method for recovering HINF from vaginal-rectal swab specimens and demonstrated low prevalence of HINF carriage rate in pregnant women. These findings highlight the need for further research to pinpoint the source for transmission of HINF to neonates.

Purpose: Bloodstream infections (BSIs) are associated with significant morbidity, mortality and costs, while prolonged blood culture (BC) diagnosis may delay the initiation of targeted therapy. This study evaluates the impact of an optimized microbiology laboratory process on turnaround times, antibiotic use, clinical outcomes and economics for hospitalized BSI patients.

Methods: A pre-post study was conducted in a Chinese hospital in which BSI derived BC results before (Oct. 2020- Sep. 2021) and after (Oct. 2021- Sep. 2022) newly implemented microbiology diagnostics and workflow changes were analyzed. Turnaround times, antibiotic initiation, length of stay and in-hospital costs were compared.

Results: From 213 included patients, 134 were pre-optimization (pre-op) and 79 were post-optimization (post-op) cases. The median time from blood sample collection (BSC) to pathogen identification (ID) decreased from 70.12 to 47.43 h post-op (P < 0.001). The median time from BSC to the first ID report related initiation of pathogen-directed antibiotic use decreased from 88.48 to 47.85 h post-op (P < 0.001). The average hospital stay decreased from 19.54 to 16.79 days and 30-day readmissions declined from 18.7 to 13.9%, while the mean total antimicrobial drug usage costs decreased by 3,889 CNY per patient (P = 0.022) after optimization.

Conclusions: Implementing new diagnostics technologies and optimizing laboratory workflows significantly reduced antimicrobial drug usage costs, shortened the time to ID results and improved the timeliness of appropriate antibiotic choices to treat BSIs. Investments in faster testing and process improvements were clearly beneficial for patient outcomes and healthcare economics.

An increase in Group A Streptococcus vulvovaginitis was detected in 2023: The average number of cases per year was 13 during 2011-2017. Twenty-five and 27 cases were reported in 2018 and 2019 followed by a decline coinciding with the COVID-19 pandemic. The 2023 increase surpassed previous data. The most frequent resistances were to erythromycin (11.3%;) and tetracycline (8.8%). Eleven different emm-types were detected among 30 GAS isolated in 2023: emm 1 was predominant (36.7%) followed by emm 89 (20%), emm 87 (10%) and emm 28 (6.7%). GAS should be increasingly considered in women with vulvovaginitis.

Purpose: Staphylococcus aureus bacteremia (SAB) is associated with a 90-day mortality of 28-34%. Many SAB-patients (7.8-39%) have a secondary S. aureus bacteriuria (SABU) mainly without symptoms of a urinary tract infection. Due to high morbidity and mortality, there is an interest in rapid detection of S. aureus bacteremia. Here, we compared a rapid nucleic acid amplification test (NAAT) with conventional culture to detect S. aureus in urine and to identify cases with increased risk for SAB.

Methods: In a cross-sectional study, we assessed urine samples (mid-stream, clean catch and catheter urine) of patients with SAB and bacteremia other than SAB (non-SAB). Urine samples were collected ± 3 days to the collection of the positive blood culture and were cultured on a set of selective and non-selective agar plates. NAAT was performed using a commercial test (Xpert^® SA Nasal Complete G3, Cepheid) from a sterile swab soaked in urine.

Results: We included samples from 100 patients (68% male, median age: 67.4 years) with SAB and 20 patients (75% male, median age: 65.84 years) with non-SAB. The sensitivity of detecting SAB from urine samples was 47% (specificity: 90%) for NAAT, when applying a Ct-value of ≤ 37.4 for positive results. Urine culture had a sensitivity of 25% and a specificity of 95%. Molecular and culture methods showed a moderate agreement (80%, Cohens kappa: 0.55).

Conclusion: NAAT from urine has a higher sensitivity than culture in patients with SAB and could potentially identify cases with increased risk for SAB. Future studies should investigate whether this characteristic could translate into a clinical benefit through rapid detection of SAB.

Purpose: People living with HIV (PWH) experience a disproportionate burden of sexually transmitted infections (STIs), leading to more severe health outcomes and increasing the risk of HIV transmission. The presence of untreated STIs can accelerate HIV disease progression, while HIV infection can complicate STI diagnosis and treatment. Despite this interconnectedness, comprehensive data on the global prevalence of specific STIs among PWH remain limited. This systematic review aims to synthesize existing data to provide a more accurate picture of the prevalence of co-infection with Treponema pallidum, Neisseria gonorrhoeae, Chlamydia trachomatis or Trichomonas vaginalis in PWH, while also identifying critical knowledge gaps and informing future research priorities.

Methods: We searched databases for eligible studies reporting the prevalence of Treponema pallidum, Neisseria gonorrhoeae, Chlamydia trachomatis, or Trichomonas vaginalis among PWH, published from January 1, 2000, to February 1, 2023. From 22,290 identified articles, 127 independent studies meeting the inclusion criteria were included in this meta-analysis.

Results: The overall global co-infection prevalence of Treponema pallidum, Neisseria gonorrhoeae, Chlamydia trachomatis, and Trichomonas vaginalis in PWH, was 4.8% (95%CI: 4.7-5.0%), 0.8% (95%CI: 0.6-0.9%), 2.5% (95%CI: 2.2-2.7%), and 3.0% (95%CI: 2.7-3.3%), respectively. The global prevalence of these four STIs in PWH is high, especially in Africa and Southeast Asia and in MSM and TGW populations. Based on the subgroup analyses, we further found that there was a high prevalence of Treponema pallidum and Chlamydia trachomatis in Southeast Asia and a high infection of Trichomonas vaginalis in the whole of Africa. Treponema pallidum infection was more common in males than females, and Chlamydia trachomatis and Trichomonas vaginalis infections were more common in females than males. Besides, high infection rates of Treponema pallidum, Neisseria gonorrhoeae, and Chlamydia trachomatis were detected in men who have sex with men (MSM) + transgender women (TGW), while high infection rates of Trichomonas vaginalis were found in sex workers and pregnant women.

Conclusion: The study confirmed high prevalence of four sexually transmitted pathogens in PWH, noting regional, gender, and subpopulation-specific differences. It offered insights for targeted interventions and healthcare strategies. The research underscored the necessity for enhanced data collection and expanded screening/treatment for vulnerable populations and regions.

Purpose: We investigated how the microscopic quality of endotracheal aspirates (ETA) impacts the performance of the Filmarray® pneumonia plus panel (FA-PP) in patients undergoing mechanical ventilation (IMV) with suspicion of lower respiratory tract bacterial infection (LRTBI).

Methods: The quality of ETA was categorized according to the number of leukocytes and buccal squamous epithelial (BSE)/field (100x magnification). G5 (< 10 BSE cells and > 25 leukocytes/field) and G4 (10-25 BSE cells and > 25 leukocytes/field) ETA were tested in parallel by the FA-PP and conventional semiquantitative culture.

Results: In total, 153 ETA were graded as G5 (from 115 patients) and 56 as G4 (from 48 patients). Focusing on "conventional" bacterial species, a trend towards more positive results (P = 0.16), and co-detections (P = 0.18) was returned by G5 ETA. Although more targets were detected on G5 ETA (P = 0.005), the spectra of bacteria detected was comparable across G5 and G4 specimens. A trend towards higher bacterial burdens as quantitated by the FA-PP, and irrespective of the target, was observed in G5 (median, 10⁶ genome copies/ml) vs. G4 ETA (median, 10⁵ genome copies/ml). The degree of full agreement between FA-PP and culture was higher for G5 ETA (Kappa value, 0.54; 95% CI, 0.43-0.66) than for G4 ETA (Kappa value, 0.31; 95% CI, 0.11-0.49). For all bacterial targets detected, genome copy/ml numbers exceeded colony forming units (CFU)/ml counts in 1-2 log₁₀, irrespective of ETA grading. The degree of correlation between genome copies/ml and CFU/ml was slightly better for G5 ETA (Rho = 0.65; P = 0.001) than for G4 ETA (Rho = 0.54; P = 0.11).

Conclusion: FA-PP testing of G5 ETA may provide more comprehensive and clinically useful information compared with G4 specimens in patients undergoing IMV with suspected LRTBI and receiving antimicrobial therapy. Yet G4 ETA may still provide useful microbiological information.

Purpose: Fungal rhinosinusitis is a significant and growing health concern in arid regions, with an increasing incidence over recent decades. Without timely and appropriate management, it can lead to severe complications, including potential intracranial spread. This study aims to establish efficient and rapid diagnostics for non-invasive fungal rhinosinusitis (FRS), addressing the challenge of its difficult-to-culture diagnosis.

Methods: Twenty-eight patients suspected of FRS were studied using endoscopic sinus surgery to obtain tissue samples for histopathology, direct microscopy, fungal culture, quantitative PCR (qPCR) and metagenomic next-generation sequencing (mNGS) detection. A patented qPCR targeting prevalent Aspergillus species was evaluated.

Results: The patient cohort had a male-to-female ratio of 9:14, with disease duration up to 50 years. Histopathologically, 23 out of 28 cases were positive. Fungal culture exhibited a sensitivity of 21.74%, with one false positive. qPCR and mNGS showed 100% sensitivity and specificity, with a 100% consistency rate for identification at the species level (23/23), and potential detection of cases with co-infections. The most common pathogen was A. flavus, followed by A. fumigatus and A. niger. Two cases involved mixed infections of A. fumigatus and A. flavus.

Conclusion: qPCR and mNGS proved effective in rapidly identifying fungi from fresh sinus tissue that are challenging to culture, surpassing conventional methods. However, further evaluation and optimization with a larger cohort of patients are necessary. Histopathology is still recommended to confirm the clinical significance of the detected fungal species.

Coronavirus disease 2019 (COVID-19), a kind of respiratory disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), primarily spreads through the respiratory tract from human to human. Its extensive and rapid spread has led to a global pandemic, causing great harm to human health and economic development all over the world. Current known evidence indicates that SARS-CoV-2 has evolved accumulating multiple mutations, with altered infectivity and viral replication capacity. A better understanding of the complications of COVID-19 and its relationship with underlying diseases is crucial for the prevention and treatment of SARS-CoV-2. This case series reviewed case data of our 4 recent patients with severe or critical COVID-19, including treatment plan, status of pulmonary infection and their microbiology workup with metagenomic next-generation sequencing with bronchoalveolar lavage fluid. This report shed light on the significance of rapid and accurate clinical diagnosis and treatment on COVID-19.