Clinical Microbiology and Infection最新文献

Objectives: To investigate whether bathing with 2% chlorhexidine gluconate (CHG) reduces the incidence of surgical site infection (SSI) in patients undergoing routine pancreatic surgery.

Methods: A randomised controlled trial was conducted at a large-volume pancreatic centre between 1 January 2021 and 31 December 2022. Patients undergoing clean-contaminated pancreatic surgery were enrolled and randomised into an intervention arm (bathing with a 2% CHG wipe) and a control arm (routine care, soap and water). The primary outcome was the incidence of SSI after pancreatic surgery within 30 days.

Results: Overall, 614 patients (311, intervention arm; 303, control arm) were included in intention-to-treat (ITT) analysis. 8.8% (54/614) patients developed SSI. The incidence of SSI in intervention arm was 6.8% (21/311) and 10.9% (33/303) in control arm, and the difference did not reach the level of statistical significance (p=0.070). The time to SSI was significantly extended when patients in the intervention arm (log-rank test, p= 0.047). The intervention did not significantly reduce the incidence of healthcare-associated infection, hospital-acquired pneumonia, and bloodstream infection. No adverse events were observed. However, in the Per-Protocol (PP) analysis among 519 patients, the intervention arm showed a significantly lower incidence of overall SSI than that of those in the control arm (21/272, 7.7% vs. 33/242, 13.4%, p=0.036).

Conclusions: Bathing with 2% chlorhexidine gluconate could potentially reduce the incidence of SSI for the patients scheduled to undergo pancreatic surgery which further well-designed clinical trials are warranted.

Objectives: Explore the presence, or absence, of virulence genes and the phylogeny of a multi-decade UK collection of clinical and reference Fusobacterium necrophorum isolates.

Methods: Three hundred and eighty-five F. necrophorum strains (1982-2019) were recovered from storage (-80°C). Illumina whole genome sequencing (WGS) was undertaken with 374/385 genomes available for examination after quality checking. Sequences were analysed, using BioNumerics (bioMérieux; v 8.1), for the presence of known virulence genes. Strain phylogeny was investigated using a bespoke Fusobacterium spp. whole genome multi-locus sequence typing (wgMLST) method and single nucleotide polymorphism (SNP) analysis.

Results: F. necrophorum ssp. necrophorum and F. necrophorum ssp. funduliforme phylogeny showed clear separation of the two subspecies and clustering of F. necrophorum ssp. funduliforme into three distinct clades. Congruence between SNP and wgMLST analysis was high (99.3%) and indistinguishable clusters were observed with wgMLST (n=3) and SNP (n=1) analysis of isolates derived from different students attending the same education setting. There was no grouping of strains by disease state or decade of isolation. No association was demonstrated with specific virulence gene detection although conspicuous virulence gene patterns were seen amongst the different subspecies and clades.

Conclusions: There was no evidence that the pathogenesis of F. necrophorum infection was associated with the presence of the virulence determinants investigated. Host-pathogen interactions should, therefore, be a focus of future research. Person-to-person transmission is a feature of this important pathogen.

Objectives: To investigate the association between quantitative T-SPOT.TB values and the risk of incident and prevalent tuberculosis disease (TBD), identify risk factors, and evaluate test accuracy.

Methods: This retrospective cohort study followed patients tested consecutively with T-SPOT.TB at Aarhus University Hospital from 2010 to 2017 through 2022. Data on demographics, comorbidities, medications, and TB status were collected from patient records and national registries. Cox proportional hazards models with restricted cubic splines assessed the risk of incident TBD (occurring ≥3 months post-test) by quantitative spot counts. Cox and log-binomial regressions identified risk factors for incident and prevalent TBD (occurring between three months before and after the test). Sensitivity, specificity, and predictive values assessed test accuracy. T-SPOT.TB was the index test, and microbiologically and/or clinically confirmed TBD was the reference standard.

Results: Among 8,542 individuals with complete follow-up, 59 developed incident TBD over 67,456 person-years. Among 9,014 individuals tested once, 162 had prevalent TBD at the time of testing. The risk of incident TBD increased with higher spot counts, plateauing for tests with more than ten spots. The strongest risk factors for both incident and prevalent TBD were categorical T-SPOT.TB results: compared to negative tests (≤4 spots), adjusted hazard ratios for incident TBD were 5.0 (95%CI: 1.9, 13.1) for borderline (5-7 spots) and 8.0 (95%CI: 4.0, 15.7) for positive tests (≥8 spots). Adjusted risk ratios for prevalent TBD were 14.9 (95%CI: 7.7, 28.9) for borderline and 35.6 (95%CI: 21.4, 59.2) for positive tests. Sensitivities for incident and prevalent TBD were 54.0% (95% CI: 39.3, 68.2) and 78.4% (95% CI: 71.3, 84.5), respectively. Specificities were 84.8 (84.0, 85.4) and 83.7 (82.9, 84.4), respectively.

Conclusions: Incident TBD risk increases with T-SPOT.TB values but plateaus beyond 10 spots. Borderline and positive T-SPOT.TB results are strongly linked to TBD risk.

Objectives: Chlamydia trachomatis is the most commonly diagnosed bacterial sexually transmitted infection (STI) worldwide. Diagnosis relies on nucleic acid amplification techniques, such as PCR, which does not distinguish between viable pathogens and residual bacterial DNA, leading to potential overdiagnosis and overtreatment. PCR with confirmation of pathogen viability has not been widely explored in the STI field. Our aim was to establish a C. trachomatis viability PCR (V-PCR) and to apply it to anorectal swabs from men who have sex with men (MSM).

Methods: We performed validation of a published V-PCR protocol by preparing artificial samples with known ratios of viable and non-viable C. trachomatis. Mock samples were treated with propidium monoazide (PMAxx^TM) before DNA extraction and quantitative PCR (qPCR) to detect C. trachomatis. The V-PCR was then applied to C. trachomatis PCR-positive anorectal swabs from MSM. Viability was expressed as the difference in C. trachomatis (CT) copies between PMAxx^TM untreated and treated samples (ΔLog10 CT/mL). The anorectal samples were inoculated in cell culture for isolation. Genotyping was performed by examining the ompA gene sequence.

Results: Of 236 anorectal swabs, 69 (29.2%) were C. trachomatis PCR-positive, and we obtained V-PCR data from 54. There were 7/54 (12.9%), samples with <1% viable CT (>2.52 ΔLog10 CT/mL) 4/54 (7.4%) samples with 1%-10% viable CT (1.59-2.52), 16/54 (29.6%) with 10.01-50% viable CT (0.86-1.59) and 27/54 (50.0%) with 50.01%-100% viable CT (<0.35-0.86). C. trachomatis was isolated successfully from 39/69 (56.5%) samples in cell culture. Genotypes based on ompA were obtained for 62/69 (89.9%) samples: G (n=15/62), D/Da (n=15/62), J (n=15/62), E (n=11/62), L1 (n=4/62) and L2 (n=2).

Conclusions: We successfully implemented a viability test based on PCR, which can distinguish, detect and quantify viable C. trachomatis in anorectal swabs from MSM. Rapid, reliable assessment of C. trachomatis viability could help to improve antimicrobial stewardship.

Objectives: Internal migrants in China frequently travel between their hometowns and the cities where they work, creating ample opportunities for cross-regional transmission of tuberculosis (TB). The aim of this study was to explore the role of internal migrants in transmitting TB across different regions and the contribution of cross-region transmission to China's TB burden.

Methods: The study included a total of 8664 patients with TB and their Mycobacterium tuberculosis isolates, collected from two large cities and three rural regions. Genomic clusters were defined as having a genomic distance of ≤12-single nucleotide polymorphisms. Cross-regional clusters were defined as clusters containing patients from at least two regions, indicative of cross-regional transmission.

Results: A total of 2403 clustered cases (27.7%) were grouped into 845 clusters, of which 142 (16.8%) were cross-regional. An increased risk for cross-regional transmission was found for internal migrants (adjusted OR (aOR), 1.45; 95% CI, 1.13-1.87), individuals aged <55 years (aOR, 2.73; 95% CI, 1.81-4.13), and housekeepers/factory workers (aOR, 1.16; 95% CI, 0.90-1.50). Among 200 cross-regional transmission events identified by transmission inference, 96 occurred between urban patients, 98 between urban and rural patients, and only six between rural patients. Notably, 93.5% (187/200) of cross-regional transmission events involved internal migrants. Epidemiological data showed that just 5.5% of cross-regional transmission events involved patients from the same township or neighbouring counties, where the transmission likely occurred.

Discussion: The mobility of the internal migrant population appears to be responsible for most cross-regional transmission of TB in China. The magnitude and dynamics of cross-regional transmission should be addressed in future strategies to reduce the incidence of TB in China.

Background: Bacteriophage (phage) therapy is a promising alternative antimicrobial approach that has the potential to transform the way we treat bacterial infections. The antibiotic resistance crisis is driving renewed interest in phage therapy. There are currently no licensed phage therapy medicinal products and phage therapy is used in small but growing patient numbers on an unlicensed basis.

Objectives: This article provides guidelines on the assessment of patient suitability for unlicensed phage therapy for clinicians in the United Kingdom.

Sources: This article builds on Health Improvement Scotland's recommendation for the consideration of phage therapy in difficult-to-treat infections and the experience of the author group, who have collectively assessed the suitability of 30 patients for phage therapy.

Content: In the United Kingdom, unlicenced medicines, including phages, may be considered to meet special clinical needs. The use of unlicenced medicines is governed by national legislation and local National Health Service trust policies. Phages can be used in any National Health Service trust and decisions about suitability should be made through existing local clinical management pathways. This article sets out guidelines to support local clinical teams in the assessment of patient suitability for phage therapy. Clinical and microbiological considerations are presented, including allergy and pregnancy.

Implications: The assessment of patient suitability for phage therapy is within the scope of local clinical teams. Local assessment through existing clinical management pathways will develop confidence and competence in phage therapy among clinical teams nationally and ensure timely patient care.