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Brain abscesses in children are uncommon but serious conditions. Bifidobacterium species, typically considered commensal organisms of the oral cavity, gastrointestinal tract, and female genital tract, are rarely implicated in invasive infections. We present a case of multiple brain abscesses caused by Bifidobacterium spp. in a previously healthy 11-year-old male, secondary to contiguous spread from chronic left-sided paranasal sinusitis with ethmoid bone erosion. Neuroimaging demonstrated left frontal abscesses with marked perilesional edema, ring enhancement and midline shift, together with opacification of the left maxillary, ethmoid and frontal sinuses. Bifidobacterium spp. was the only organism isolated from both the brain abscess aspirate and the sinus samples. The patient was treated with burr-hole aspiration of the abscesses and same-session endoscopic sinus surgery, followed by six weeks of intravenous crystalline penicillin G. He achieved full clinical recovery without neurological sequelae, with stable residual changes on follow-up MRI. To our knowledge, this is the first detailed case report of a brain abscess caused by Bifidobacterium spp. in a previously healthy pediatric patient. This case highlights the potential of this typically commensal organism to cause serious central nervous system infection via contiguous spread from the paranasal sinuses.

Objectives: Enterotoxemia, caused by Clostridium perfringens, leads to high mortality in ruminants and significant economic losses. This study aimed to toxinotype C. perfringens using the Ag-ELISA method in suspected samples from the Central Black Sea Region and surrounding provinces, while statistically and ecologically evaluating the effects of regional abiotic factors on the spread of the disease.

Methods: Between 2021 and 2024, the Ag-ELISA test was applied to 741 intestinal content samples submitted from 11 provinces to the Samsun Veterinary Control Institute. Meteorological parameters and soil moisture index data derived from NASA satellites were utilized. Generalized Linear Mixed Models (GLMMs) based on the Negative Binomial distribution were used to determine the effects of variables, while Kernel Density Estimation (KDE) was employed to model the ecological niche distribution and case concentrations based on mean temperature and soil moisture.

Results: C. perfringens and its toxins were detected in 297 (40.08%) of the samples. Toxinotyping revealed that Type A was the most prevalent strain (62.63%), followed by Type C (20.54%), Type D (13.80%), and Type B (3.03%). GLMM and KDE analyses demonstrated that soil moisture and temperature are the most influential risk factors. The KDE contour layers revealed that the cases exhibited a bimodal adaptive mechanism and specific ecological niche concentrations based on these abiotic variables.

Conclusions: C. perfringens Type A and Type C were identified as the dominant strains in the study area. Considering the bimodal adaptive mechanism and environmental niche concentrations demonstrated by KDE, selecting vaccines providing targeted protection against Types A and C is of critical importance for controlling enterotoxemia and optimizing strategic vaccination schedules in the region.

Objectives: To characterise the phenotypic and genotypic antimicrobial resistance (AMR) profiles and genomic diversity of vaginal Prevotella bivia isolates obtained from South African women and to compare them with publicly available genomes.

Methods: P. bivia isolates were recovered from lateral vaginal wall swabs and identified by polymerase chain reaction (PCR) and 16S rRNA gene sequencing. Antimicrobial susceptibility testing against metronidazole, clindamycin, azithromycin, amoxicillin and doxycycline was performed using MIC test strips (MTS). Whole-genome sequencing was undertaken using the Illumina MiSeq platform to investigate genomic diversity, AMR gene carriage and mobile genetic elements.

Results: Thirty-five P. bivia isolates from 30 vaginal samples underwent phenotypic characterisation, and 33 high-quality genomes were included in genomic analyses. Resistance to metronidazole and clindamycin was low (11.4% and 8.6%, respectively). The tetQ and cfxA genes were the most frequently detected AMR determinants (90.9% and 72.7% of genomes, respectively), whereas ermF and nimK were rare (3.0% each). Comparative genomic analysis revealed generally low within-sample diversity, although one participant harboured genetically distinct strains, and strain persistence was observed in another participant over a 16-week interval. South African isolates clustered separately from most publicly available isolates originating from the United States. One isolate harboured nimK within a previously described Tn6456-like mobile element, representing, to our knowledge, the first identification of nimK in a South African vaginal P. bivia isolate.

Conclusions: Vaginal P. bivia isolates from South African women exhibited low genomic diversity, evidence of strain persistence and occasional co-colonisation with multiple P. bivia strains. Although resistance to standard bacterial vaginosis therapies remained low, the presence of mobile AMR determinants highlights the importance of continued genomic and phenotypic surveillance of vaginal P. bivia populations.

Clostridioides difficile infection (CDI) remains a major cause of antibiotic-associated diarrhea and colitis, with a high rate of recurrence. Current CDI treatments rely largely on antibiotics that perpetuate dysbiosis or on microbiota-based interventions with limited accessibility, emphasizing the need to explore novel, targeted microbiota-derived therapies. Probiotics have emerged as a potential approach for the prevention and management of CDI, owing to their capacity to modulate the gut microbiota and host immune responses. Among them, bifidobacteria are prominent commensal anaerobes of the human gut with well-documented health-promoting properties. Although their role in CDI has been less extensively explored than that of other probiotic microorganisms, accumulating evidence suggests that bifidobacteria may exert both direct antagonistic effects against C. difficile and indirect benefits through the restoration of eubiosis and attenuation of inflammation. This review summarizes recent in vitro, in vivo, and clinical studies investigating the effects of bifidobacteria in the context of CDI. We discuss mechanisms including inhibition of C. difficile growth and toxin activity, modulation of host inflammatory responses, and interactions with the intestinal microbiota. Particular attention is given to studies published over the past decade. Overall, bifidobacteria emerge as promising candidates for future probiotic or microbiota-based interventions targeting CDI, although further well-designed clinical trials are needed to establish their efficacy and optimal modes of use.

We previously identified an intact Enterobacteriaceae-derived plasmid (pCA17) in the draft genome sequence of C. acnes strain CA17. In the absence of this isolate for laboratory confirmation, we performed in silico analyses, including comparative gene synteny, replicon typing, GC content, and CAI analysis, supporting pCA17 as a likely contaminant.

Objective: This study aims to evaluate the performance of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) for species identification of human Capnocytophaga and to confirm results by whole-genome sequencing.

Methods: Six reference strains, representing human Capnocytophaga species and one taxon, and a total of 126 clinical strains, selected based on their biochemical profiles from a large collection of preliminarily identified Capnocytophaga isolates, were analyzed.

Results: Of those, 125 strains (94%) were identified at least at the genus level (log score variation of 1.7-1.999), while 52 strains (39%) were identified at the species level with a cut-off score of ≥2.0. Eight strains (6%) remained unidentified with a log score of <1.69. C. leadbetteri and Capnocytophaga genospecies AHN8471 strains were accurately identified at the genus level. Minor identification errors were observed in three cases: C. leadbetteri (n=1), C. ochracea (n=2), and Capnocytophaga genospecies AHN8471 (n=38). MALDI-TOF MS was unable to distinguish between C. sputigena and Capnocytophaga genospecies AHN8471 at the species level but clustered them together in the Main Spectra Profile (MSP) dendrogram.

Conclusions: MALDI-TOF MS shows promise as a diagnostic tool for identifying human Capnocytophaga species when correct taxonomy and sufficient reference strains are available in the database. Based on the close phenotypic, ribosomal, and genotypic structures, we propose to establish the term "C. sputigena group" encompassing C. sputigena, Capnocytophaga genospecies AHN8471, and other related Capnocytophaga variants. Nevertheless, updating and expanding the MALDI-TOF MS reference database is essential to improve identification accuracy.