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Brucella endocarditis is a rare but life-threatening complication of brucellosis and accounts for most disease-related deaths. Mycotic aneurysm is an even rarer extracardiac manifestation of infective endocarditis and may cause catastrophic hemorrhage. We describe a 58-year-old man with prosthetic aortic valve endocarditis due to Brucella spp. who developed intracranial hemorrhage following rupture of a posterior cerebral artery mycotic aneurysm. The patient was successfully treated with prolonged combination antimicrobial therapy and endovascular coil embolization, without cardiac or neurosurgical intervention. We also reviewed previously reported cases of Brucella endocarditis complicated by mycotic aneurysm to summarize their clinical characteristics, diagnostic approaches, and treatment outcomes. Our case highlights an exceptionally rare presentation and demonstrates that favorable outcomes can be achieved through a combined medical and endovascular strategy.

Keywords: Brucellosis, endocarditis, mycotic aneurysm, cerebral hemorrhage, endovascular treatment

Objective: Although HIV RNA can be suppressed with antiretroviral therapy (ART), chronic inflammation may persist in people living with HIV (PLWH). Because a low CD4/CD8 ratio is associated with morbidity and mortality, this study aimed to evaluate factors associated with CD4/CD8 ratio normalization, defined as achieving CD4/CD8 ≥1.

Materials and Methods: This retrospective cohort study included PLWH aged ≥18 years who were diagnosed between 2010 and 2017 and achieved viral suppression within the first year after starting ART. Data were retrospectively obtained from a tertiary infectious diseases clinic.

Results: Among 217 patients followed for five years, 187 (86.2%) achieved CD4⁺ >500 cells/μL and 87 (40.1%) reached a CD4/CD8 ≥1. In multivariable logistic regression, higher baseline CD4⁺ T-cell count and baseline CD4⁺/CD8⁺ ratio were independently associated with CD4/CD8 ratio normalization.

Conclusion: Including immunological markers alongside viral suppression may better reflect treatment success. Baseline immunological status appears to be associated with long-term CD4/CD8 ratio normalization in PLWH receiving suppressive ART. Monitoring these markers may help inform long-term follow-up strategies.

Keywords: CD4-CD8 ratio, HIV, viral suppression, immune reconstitution, chronic inflammation, antiretroviral therapy (ART)

Objective: Staphylococcus aureus is a leading cause of community-acquired skin and soft tissue infections (SSTIs), for which empirical oral therapy is frequently initiated in outpatient practice. Ongoing shifts in antimicrobial resistance may compromise the reliability of commonly prescribed non–β-lactam agents. This study evaluated six-year trends in methicillin resistance and susceptibility to widely used non–β-lactam oral antibiotics among outpatient-derived S. aureus isolates.

Materials and Methods: In this retrospective observational study, non-duplicate S. aureus isolates recovered from wound, abscess, and tissue specimens of outpatients between January 2020 and December 2025 were analyzed. Identification was performed using MALDI-TOF MS. Antimicrobial susceptibility testing and methicillin resistance screening (cefoxitin) were conducted in accordance with EUCAST criteria. Resistance to clindamycin, tetracycline, trimethoprim–sulfamethoxazole (TMP-SMX), and inducible clindamycin resistance (iMLSB phenotype) were assessed. Temporal trends were analyzed statistically.

Results: A total of 1,890 isolates were included, of which 655 (34.6%) were methicillin-resistant (MRSA). The proportion of MRSA increased significantly over time, reaching 39.0% in 2025. Significant upward trends were observed for clindamycin, inducible clindamycin, and tetracycline resistance (all p for trend ≤0.004). In contrast, TMP-SMX resistance remained consistently low (<5%) without a significant increase. MRSA isolates demonstrated markedly higher resistance rates than methicillin-susceptible strains. Adults exhibited higher resistance to methicillin and tetracycline than children.

Conclusion: Rising MRSA prevalence and declining activity of clindamycin and tetracycline may limit empirical oral treatment options for outpatient SSTIs. TMP-SMX retained stable in vitro activity. Continuous outpatient-focused surveillance is essential to support evidence-based empirical therapy.

Keywords: Staphylococcus aureus, MRSA, skin and soft tissue infections, outpatient surveillance, antimicrobial resistance

Objective: This study aimed to investigate the differences in HIV/AIDS knowledge and attitudes across medical students at distinct academic stages, evaluating their relation to a structured Infectious Diseases and Clinical Microbiology (IDCM) clerkship and sociodemographic characteristics.

Materials and Methods: This research was conducted as a cross-sectional and comparative study from 1 March 2024 to 5 July 2024. The medical students were divided into three cohorts: third-year (preclerkship), fourth-year (postclerkship), and fifth-year (postclerkship, advanced-stage) students. This study does not follow the same individuals over time but compares different cohorts at distinct educational stages.

Results: The study included 291 medical students (median age 22; 51.9% male). Among fourth-year students, the IDCM clerkship significantly increased median knowledge scores from 19 (9–21) to 20 (13–21) and attitude scores from 54 (26–85) to 57 (17–85). Knowledge scores were 18 (9–21) for third-year, 20 (13–21) for fourth-year (posttest), and 19 (12–21) for fifth-year students; attitude scores were 51 (22–80), 57 (17–85), and 55 (19–76), respectively. Knowledge and attitude scores were significantly higher in the post-clerkship fourth-year cohort than in the third-year cohort. Knowledge increased in fifth-year vs third-year students, though attitude differences were non-significant. IDCM clerkship independently predicted higher knowledge. Female gender, the clerkship, and paternal education predicted positive attitudes.

Conclusion: HIV/AIDS knowledge scores were significantly higher among cohorts who had completed the IDCM clerkship; however, attitudinal differences across cohorts were less prominent. These findings suggest that while higher educational stages are associated with higher cognitive scores, differences in professional attitudes may require more integrated, long-term educational strategies across the curriculum.

Keywords: HIV/AIDS, medical education, stigma, socio-demographic factors

Objective: Invasive non-typhoidal Salmonella (iNTS) infection may cause severe systemic and focal disease, particularly in patients with comorbidities or immunosuppression. Data on the clinical features and antimicrobial resistance patterns of iNTS infections in Türkiye remain limited. We evaluated the clinical and microbiological characteristics of adult patients with microbiologically confirmed iNTS infection.

Materials and Methods: This retrospective single-center case series included adult patients diagnosed with iNTS infection at a tertiary-care hospital in Türkiye between 2015 and 2025. iNTS infection was defined as isolation of non-typhoidal Salmonella from blood or other sterile body sites. Clinical, microbiological, antimicrobial susceptibility, and outcome data were analyzed.

Results: Nine patients with iNTS infection were identified. The median age was 54 years (IQR: 45–68), and five patients (55.6%) were male. Underlying comorbidities were present in eight patients (88.9%), most commonly hypertension, diabetes mellitus, autoimmune diseases, and HIV infection. Gastrointestinal symptoms were observed in only two patients (22.2%), whereas seven patients (77.8%) presented without typical enteric manifestations. Bacteremia was detected in seven patients (77.8%), and focal invasive infections were identified in five patients (55.6%), including spondylodiscitis, septic arthritis, thyroid abscess, and liver abscess. Salmonella enterica serovar Enteritidis was the predominant serovar, identified in six isolates (66.7%), while three isolates (33.3%) were classified as Salmonella enterica subsp. enterica without further serovar determination. All isolates remained susceptible to third-generation cephalosporins, whereas resistance to ampicillin and ciprofloxacin was detected in four (44.4%) and three isolates (33.3%), respectively. The median length of hospitalization was 16 days, and two patients (22.2%) died during follow-up.

Conclusion: iNTS infection may present with heterogeneous and frequently non-enteric manifestations, particularly in adults with significant comorbidities or immunosuppression. The high frequency of focal invasive disease and elevated ciprofloxacin resistance in this series highlight the importance of early microbiological diagnosis, evaluation for metastatic infectious foci, and appropriate empirical antimicrobial therapy.

Keywords: Invasive non-typhoidal Salmonella, bacteremia, focal infection, antimicrobial resistance, case series

Pasteurella multocida, a Gram-negative coccobacillus commonly found in the oropharyngeal flora of cats, is a rare cause of peritoneal dialysis–associated peritonitis. We report a 44-year-old patient with exposure to stray cats who presented with abdominal pain and cloudy dialysis effluent. Laboratory tests revealed leukocytosis and elevated CRP, and empirical intraperitoneal cefazolin was started. Peritoneal fluid culture yielded P. multocida, resistant to fluoroquinolones, but susceptible to penicillin, cefotaxime, trimethoprim-sulfamethoxazole, and tetracycline. The patient showed rapid clinical improvement. This case highlights the need to assess animal exposure in PD patients and underscores emerging resistance patterns within a One Health approach.

 Keywords: Pasteurella multocida, peritoneal dialysis, peritonitis

Crimean–Congo hemorrhagic fever (CCHF) is a life-threatening viral infection that may mimic HELLP syndrome during pregnancy. We describe a 30-year-old woman at 23 weeks’ gestation presenting with fever, myalgia, thrombocytopenia, and severe transaminase elevation. Initial suspicion of HELLP syndrome was reconsidered due to high fever, rural exposure, and rapidly progressive coagulopathy. CCHF was confirmed by polymerase chain reaction. Despite intensive supportive therapy and plasma exchange, fulminant multiorgan failure developed, resulting in simultaneous maternal and fetal death. This case underscores the need to consider CCHF in febrile pregnant patients with thrombocytopenia in endemic areas.

Keywords: Crimean-Congo hemorrhagic fever, pregnancy, HELLP syndrome, thrombocytopenia, maternal and fetal mortality, differential diagnosis

Ochrobactrum species are aerobic, non-fermenting Gram-negative bacilli that are increasingly recognized as causes of healthcare-associated infections. Among them, Ochrobactrum intermedium remains a rare human pathogen and poses therapeutic challenges due to its resistance to multiple antimicrobial agents. We report a case of hospital-acquired sepsis caused by O. intermedium bacteremia in an 82-year-old woman with advanced pancreatic cancer. Clinical resolution was achieved following removal of the central venous catheter and a seven-day course of intravenous meropenem. This case underscores the role of O. intermedium as an emerging opportunistic pathogen in immunocompromised patients.

Keywords: Bacteremia, Ochrobactrum intermedium, catheter-related bloodstream infection, healthcare-associated infection

Gardnerella vaginalis (G. vaginalis) pneumonia in men is very rare, with most reported cases occurring in critically ill patients with major predisposing conditions. We describe a man in his 60s with poorly controlled diabetes mellitus who developed G. vaginalis pneumonia complicated by septic shock after an influenza-like illness in the setting of household influenza exposure. He required mechanical ventilation, and G. vaginalis was isolated from both sputum and blood cultures. Empirical meropenem, vancomycin, and azithromycin were de-escalated to intravenous ampicillin according to susceptibility testing, followed by oral clindamycin, for a total treatment duration of 6 weeks. Despite the absence of trauma, prolonged mechanical ventilation before onset, or a clear aspiration event, he developed severe pneumonia with lung abscess formation and achieved full clinical and radiographic recovery.

Keywords: Gardnerella vaginalis, pneumonia, septic shock