European Journal of Clinical Microbiology & Infectious Diseases最新文献

Purpose: In November 2023, the National Reference Laboratory for Enteroviruses (Budapest, Hungary) received stool, pharyngeal swab and cerebrospinal fluid samples from five newborns suspected of having human parechovirus (PEV-A) infection. The neonates were born in the same hospital and presented with fever and sepsis-like symptoms at 8-9 days of age, and three of them showed symptoms consistent with central nervous system involvement. PEV-A positivity was confirmed by quantitative reverse transcription polymerase chain reaction.

Methods: To determine the PEV-A genotype responsible for the infections, fecal samples of four neonates were subjected to metagenomic sequencing. For further analyses, amplicon-based whole genome sequencing was performed directly from the clinical samples.

Results: On the basis of whole genome analysis, sequences were allocated to PEV-A genotype 3 (PEV-A3) and consensus sequences were identical. Two ambiguities were identified in the viral protein 1 (VP1) region of all sequences at a frequency of 17.7-53.7%, indicating the simultaneous presence of at least two quasispecies in the clinical samples. The phylogenetic analysis and similarity plotting showed that all sequences clustered without any topological inconsistencies between the P1 capsid and P2, P3 non-capsid regions, suggesting that recombination events during evolution were unlikely.

Conclusion: Our findings suggest that the apparent cluster of cases were microbiologically related, and the results may also inform future investigations on the evolution and pathogenicity of PEV-A3 infections.

Purpose: To investigate the epidemiological and clinical characteristics of pertussis in children and close contacts.

Methods: Nasopharyngeal swabs and blood samples of clinically suspected children with pertussis and their close contacts from 2018 to 2022 were collected for pathogen detection of Bordetella pertussis. Questionnaires were designed to investigate the basic information and infection status of pertussis children cases and their close contacts. Descriptive epidemiological analysis was performed on the results.

Results: 1229 confirmed children cases of pertussis were collected and infants < 1 year old were the most affected (77.7%). Etiological data were collected from 587 close contacts of 269 confirmed cases and the infection rate was high (24.4%). The positive detection rate of parents, especially mothers, was significantly higher than that of other groups (32.2% vs. 18.4%, P < 0.001); The rates of misdiagnosis or missed diagnosis in pertussis children (92.2%) and close contacts (99.8%) were very high, and the distribution of symptoms between pertussis children and their close contacts was different (χ² = 535.328, P < 0.001); The vast majority of pertussis children (84.0%) were diagnosed with upper respiratory tract infection or trachea/bronchitis while 91.0% of close contacts did not seek medical attention (χ² = 685.373, P < 0.001).

Conclusion: Infants < 1 year old are at high risk in pertussis. Pertussis infection in close contacts of confirmed children is underestimated. Caregivers who are positive for pertussis but missed or misdiagnosed seriously may be a main source of pertussis infections in children. Adjusting the current pertussis immunization strategy in China is necessary.

Purpose: This study describes a pseudo-outbreak of Bacillaceae spp. bloodstream infections that spanned five months starting in May 2023 and the infection prevention measures implemented to control it.

Methods: This retrospective study was conducted at a tertiary infectious disease hospital in Bucharest, Romania. An observational audit of the blood culture collection practice in our hospital was performed, and the materials used during blood culture collection were sampled. Bacterial colonies were identified using MALDI Biotyper. The Bacillaceae blood culture positivity rates in the previous four years were compared using the Kruskal‒Wallis rank test.

Results: Bacillaceae spp.-positive blood cultures were recovered from 60 patients over a five-month period. In the case of 58 patients, Bacillaceae spp.-positive blood cultures were considered contaminated. Two patients were treated for Bacillus spp. bacteraemia. The audit revealed significant variation during the preparation of the venipuncture site step and the use of nonsterile medical cotton wool. Medical cotton wool contaminated with species of Bacillaceae was found in 10 out of 12 wards. The control measures included repeated training on the blood culture collection procedure and the removal of Bacillaceae spp.-contaminated cotton wool.

Conclusions: The pseudo-outbreak was caused by the unjustified use of medical cotton wool for disinfection of the skin and blood culture bottle septums. The investigation of this pseudo-outbreak highlighted a gap in blood culture collection practices at our facility and thus allowed for its improvement.

Purpose: Chronic suppurative otitis media (CSOM) is characterized by persistent inflammation of the mucous membrane of the middle ear and mastoid. One of the primary causative agents of CSOM is P. aeruginosa, known for its production of virulent toxins and enzymes. Some cases of CSOM, improvement may not occur despite treatment lasting three weeks, leading to what is termed refractory CSOM. This research aims to characterize the P. aeruginosa strains isolated from patients with refractory CSOM in Gyeongsangnam-do, South Korea, providing insights into their pathogenic profiles.

Methods: We conducted a retrospective analysis of P. aeruginosa isolates from the otorrhea of patients diagnosed with CSOM at a tertiary hospital in Gyeongsangnam-do, over a period from January 2005 to August 2022. The strains were examined using multilocus sequence typing (MLST) and toxin gene assay to assess genetic diversity and virulence.

Results: 39 samples were obtained from 13 cases of refractory CSOM and 15 cases of non-refractory CSOM. The findings unveiled that the P. aeruginosa cultured from patients with refractory CSOM belonged to the P. aeruginosa sequence type 235 (ST235) strain, which harbors the exoU gene as a major virulence factor.

Conclusion: The detection of ST235 in refractory CSOM signifies a challenging clinical scenario. Given the genotype's strong virulence and antibiotic resistance, identifying ST235 through MLST can guide effective management approaches, including potential surgical intervention. This study underscores the necessity of broader epidemiological investigations to understand ST235 behavior and advocates for patient education to mitigate the impacts of this formidable pathogen in CSOM.

Background: Diagnosis of Lyme borreliosis (LB) relies on clinical symptoms and detection of Borrelia-specific antibodies. Guidelines recommend a two-tier testing (TTT) strategy for disseminated LB: serological screening with a sensitive enzyme immunoassay (EIA) and confirmation with a specific immunoblot. Searching for the most sensitive and specific approach, this retrospective study evaluated standard (STTT) and modified (MTTT) strategies using a well-defined study population.

Methods: Cases included patients with active Lyme neuroborreliosis (LNB; n = 29) or Lyme arthritis (LA; n = 17). Controls comprised patients treated for LNB (n = 36) or LA (n = 8), healthy individuals who were either untreated (n = 75) or treated for LB (n = 15) in the past, and patients with potentially cross-reactive diseases (n = 16). Sera were subjected to three EIAs and two immunoblots. Reactive screening results were confirmed by immunoblot (STTT) or EIA (MTTT). Solitary IgM results in the screening assay and effects of antibiotic treatment on isotype-specific seropositivity rates were also assessed.

Results: Sensitivities of STTT strategies ranged from 90%-97% for LNB and were 100% for LA. MTTT strategies were 100% sensitive. Specificities ranged from 89%-95% for STTT and from 88%-93% for MTTT strategies. Differences between STTT and MTTT strategies were not statistically significant. Solitary IgM reactivity was common among controls. Antibiotic treatment significantly reduced IgM/IgG positivity for LNB patients; for LA patients, a decline was only observed for IgM.

Conclusion: In conclusion, MTTT strategies showed a slightly higher sensitivity and similar specificity compared to STTT strategies. Since EIAs are more time- and cost-efficient, MTTT strategies seem more favorable for clinical use. IgG testing enhances specificity with minimal sensitivity loss.

Previous reports focusing on cefiderocol susceptibility against Stenotrophomonas maltophilia have included a large number of noninvasive or colonized isolates, and data focusing on invasive S. maltophilia strains are still lacking. We retrospectively investigated the cefiderocol susceptibility of stored S. maltophilia strains that caused bacteremia at two Japanese hospitals. The MIC₅₀ and MIC₉₀ were 0.06 μg/mL and 0.25 μg/mL, respectively, while the susceptibility rate was 99.3% (current CLSI breakpoint criteria). Our results provide the MIC distribution of bacteremic S. maltophilia isolates in Japan and show the preserved cefiderocol susceptibility of S. maltophilia among clinically invasive pathogenic strains.

Purpose: Next-generation sequencing (NGS) tools have clinical advantages over blood culture but are more expensive. This study assesses the budget impact and break-even point of NGS testing costs from a healthcare provider's perspective in Germany.

Methods: The budget impact was calculated based on aggregated data of German post-operative surgery cases. Simulated cost savings were calculated based on a simulated reduction in hospital length of stay (LOS) of four or eight days with a positivity rate of 71% and compared to the costs of one (scenario A) or two tests (scenario B) per case. Furthermore, the break-even point of the cost of two tests compared to saved costs through shortened LOS was conducted.

Results: For 9,450 cases, an average budget impact for scenario A and scenario B of €1,290.41 [95% CI €1,119.64 - €1,461.19] and - €208.59 [95% CI - €379.36 - - €37.81] was identified for gastrointestinal and kidney surgery cases, and €1,355.58 [95% CI €1,049.62 - €1,661.55] and €18.72 [95% CI - €324.69 - €287.24] for vascular artery surgery cases, respectively. The break-even analysis showed that using two tests per case could achieve a minimum positive contribution margin with an average of 1.9 tests per case across the study population.

Conclusion: The results revealed a positive budget impact for one NGS test and a slightly negative budget impact for two NGS tests per case. Findings suggest that largest cost savings are generated for more severe cases and are highly dependent on the patient population.

Background: Diagnostic methods for native vertebral osteomyelitis (NVO) often yield inconclusive results. Image-guided spine biopsies for culture are specific but diagnose NVO in only 50% of cases. Pre-exposure to antimicrobials further reduces diagnostic yield. Our study assesses the value of neutrophil percentage in disc space fluid and vertebral body (DS/VB) samples for diagnosing NVO.

Methods: Adults referred for spine biopsy at Mayo Clinic from August 2022 to September 2023 were consented and enrolled at the time of biopsy. Following routine specimen collection, the biopsy needle was rinsed in saline into an EDTA tube for cell analysis. NVO diagnosis required organism identification in spine tissue or blood and/or positive histopathology, and consistent symptoms and imaging.

Results: Sixty-eight patients were prospectively enrolled, comprising 14 with NVO and 54 with alternative diagnoses. The median biopsy sample polymorphonuclear (PMN) percentage for NVO patients was 80.5% (IQR 72.5-85.2), compared to 64.5% (IQR 54.0-69.0) for those without NVO (p < 0.001). Nine (64.3%) NVO patients received antibiotics within 10 days prior to spine biopsy. As a continuous measure, PMN differential showed a moderately strong ability in classifying NVO status with an area under ROC curve of 0.795; an optimal point on the curve of 71.5% corresponded to a sensitivity of 78.6%, specificity of 79.6%, negative predictive value of 93.5% and positive predictive value of 50.0%.

Conclusion: PMN differential in DS/VB biopsies may serve as an effective diagnostic tool in the evaluation of patients with NVO particularly in ambiguous cases with an initially negative spine biopsy. Future efforts will aim to implement these findings within routine clinical practice.

Introduction: Understanding the dynamics that may characterize the emergence of KPC variants with resistance to novel β-lactam/β-lactamase inhibitor combinations (βL/βLICs) represents a challenge to be overcome in the appropriate use of recently introduced antibiotics.

Methods: Retrospective case series describing development of multiple resistance to novel βL/βLICs in patients with KPC-producing Klebsiella pneumoniae (KPC-Kp) infections treated with these drugs. Clinical-microbiological investigation and characterization of longitudinal strains by Whole-Genome Sequencing were performed.

Results: Four patients with KPC-Kp bloodstream infections were included. Most frequent clinical features were kidney disease, obesity, cardiac surgery as reason for admission, ICU stay, treatment with ceftazidime/avibactam, and pneumonia and/or acute kidney injury needing renal replacement therapy as KPC-Kp sepsis-associated complications. The development of resistance to ceftazidime/avibactam was observed in four longitudinal strains (three of which were co-resistant to aztreonam/avibactam and cefiderocol) following treatments with ceftazidime/avibactam (n = 3) or cefiderocol (n = 1). Resistance to meropenem/vaborbactam and imipenem/cilastatin/relebactam was observed in one case after exposure to ceftazidime/avibactam and imipenem/cilastatin/relebactam. Resistome analysis showed that resistance to novel βL/βLICs was related to specific mutations within bla_KPC carbapenemase gene (D179Y mutation [KPC-33]; deletion Δ242-GT-243 [KPC-14]) in three longitudinal strains, while porin loss (truncated OmpK35 and OmpK36 porins) was observed in one case.

Conclusion: Therapy with novel βL/βLICs or cefiderocol may lead to the selection of resistant mutants in the presence of factors influencing the achievement of PK/PD targets. KPC variants are mainly associated with resistance to ceftazidime/avibactam, and some of them (e.g. KPC-14) may also be associated with reduced susceptibility to aztreonam/avibactam and/or cefiderocol. Loss of function of the OmpK35 and OmpK36 porins appears to play a role in the development of resistance to meropenem/vaborbactam and/or imipenem/relebactam, but other mechanisms may also be involved.

Purpose: COVID-19 and influenza infections have similar modes of transmission and clinical symptoms but have different prognoses and treatment methods; therefore, it is important to make a final diagnosis. Herein, we aimed to compare the demographic, clinical, and laboratory differences in hospitalized pediatric patients with COVID-19 and influenza.

Methods: This retrospective study comprised patients with COVID-19 managed between March 2020 to February 2022, and patients with influenza managed between December 2017 to February 2022, at a tertiary care hospital. The clinical data and laboratory parameters were obtained from the medical records of the hospital. Pediatric intensive care unit (PICU) admission, need for oxygen support, and the mortality rates of the patients were recorded and compared statistically.

Results: Overall, 107 patients with COVID-19 and 250 patients with influenza were included. Underlying chronic disease (UCD) rates were statistically higher in patients with COVID-19 (p < 0.001). When the symptoms were compared, fever, cough, and runny nose were more common in patients with influenza, and abdominal pain and rash were more common in patients with COVID-19 (p < 0.05). In patients with influenza, white blood cell count and absolute neutrophil count values were lower (p = 0.021 and p = 0.037, respectively), and aspartate aminotransferase and creatinine kinase values were higher (p = 0.007 and p < 0.001, respectively). PICU admission rates and oxygen support needs were similar in both groups (p > 0.05). When the virus was COVID-19, it had 7.8 times higher risk of mortality compared to influenza (p = 0.002). There were statistically significant risk for mortality when the virus was COVID-19, the risk of mortality was 6.9 times higher in those with UCD, 8.5 times higher in those with admission to PICU and 3.8 times higher in those with needing mechanical ventilation (MV) compared to when the virus was influenza (p = 0.004, p = 0.006 and p = 0.049, respectively). The mortality rate was higher in patients with COVID-19 (p = 0.007).

Conclusion: This study showed that COVID-19 might negatively affect the survival times and increase mortality rates, especially in children with an UCD, admitted to the PICU and in need of MV.