Early Access

Objective: Granulomatous mastitis (GM) is a chronic inflammatory breast disease with heterogeneous clinical presentation and uncertain optimal management. Increasing evidence suggests a role for Corynebacterium species, particularly Corynebacterium kroppenstedtii, in its pathogenesis. To evaluate the clinical characteristics, treatment strategies, and outcomes of granulomatous mastitis, with particular emphasis on cases associated with Corynebacterium species and the impact of antibiotic therapy.

Materials and Methods: This retrospective cohort study included 165 female GM patients treated at a university hospital between January 2018 and January 2023. Patients were grouped according to Corynebacterium isolation (25 positive, 140 negative). Clinical characteristics, microbiological findings, and treatment modalities—oral steroids, combined antibiotic–steroid therapy, antibiotics with intralesional steroids, and segmental mastectomy—were evaluated. The impact of lipophilic antibiotics (tetracyclines, linezolid, rifampicin) combined with steroids was assessed. Recurrence rates and associated factors, including symptom duration, were analyzed using Chi-square, Fisher’s exact, Student’s t-test, or Mann–Whitney U test.

Results: Corynebacterium spp. were detected in 15.15% of cases, with C. kroppenstedtii identified in 8.48%. Patients with Corynebacterium-associated GM had more extensive abscess formation and required more interventional procedures. Multimodal treatment strategies combining steroids, antibiotics, and surgery resulted in favorable outcomes. Lipophilic antibiotics combined with steroids showed a positive but statistically nonsignificant effect. Recurrence occurred in 16.3% of patients and was associated with longer symptom duration.

Conclusion: Accurate microbiological identification is essential in GM, particularly in C. kroppenstedtii infections, to guide targeted antibiotic therapy and reduce recurrence. Tailored management strategies, including lipophilic antibiotics, may improve outcomes. Further studies are needed to define optimal treatment duration and the role of surgery in refractory GM.

Key-words: Granulomatous mastitis, Corynebacterium kroppenstedtii, breast abscess, Corynebacterium infections, anti-bacterial agents

Objective: Contaminated environmental surfaces contribute to transmission of pathogens that cause healthcare-associated infections. The present study aimed to assess the efficacy and analyze the cost of a chlorine-based combined detergent-disinfectant applied for environmental decontamination around methicillin-resistant Staphylococcus aureus (MRSA) patients.

Materials and Methods: The study was conducted in the inpatient wards (medical, surgical and orthopaedic) of Infectious Disease Control Training Centre, the Hong Kong Special Administrative Region of the People’s Republic of China over six months. The surrounding areas of newly diagnosed MRSA patients were divided into two equal halves, and decontaminated either by the conventional two-step process (cleaning with detergent followed by disinfection with 1,000 ppm hypochlorite solution), or by a new one-step method using a combined detergent-disinfectant. High-touch areas of patient’s surroundings were sampled to detect MRSA by culture and measure adenosine triphosphate (ATP) levels before and after decontamination. The number of disposable wipes used and the duration of the decontamination process were recorded for cost analysis.

Results: Both the conventional and new methods significantly reduced MRSA detection rate from 68.7% to 12.7% and 15.3% respectively (p<0.001), and significantly reduced ATP failure rate from 78.2% to 2.7% and 4.5% respectively (p<0.001). Compared with the conventional method, the new method saved an average of 5.9 minutes of decontamination time and 10.2 pieces of disposable wipes per patient, resulting in a substantial cost saving of over 6 million Hong Kong dollars per year in total according to currently recommended infection control practices for MRSA patients in public hospitals in Hong Kong.

Conclusion: The one-step method using a combined detergent-disinfectant effectively decontaminated high-touch hospital surfaces of patient environment while reducing time and costs. Its wider adoption in local inpatient settings can be considered to enhance environmental hygiene at a lower cost.

 Keywords: Decontamination, Methicillin-Resistant Staphylococcus aureus, detergents, disinfectants, costs and cost analysis

Objective: Surgical antimicrobial prophylaxis (SAP) is a key strategy for preventing surgical site infections (SSIs), yet its implementation in clinical practice remains variable despite established guideline recommendations. This study aimed to assess neurosurgeons’ knowledge and practices regarding SAP in Türkiye and to evaluate their adherence to current guideline recommendations.

Materials and Methods: This multicenter, cross-sectional study was conducted among actively practicing neurosurgeons across Türkiye using an online survey. A structured questionnaire, informed by relevant national and international guideline recommendations, collected data on demographic characteristics and key aspects of SAP, including antibiotic selection, timing of initiation, dosing strategies, and duration of prophylaxis. Categorical variables were analyzed using the chi-square test, and a p-value <0.05 was considered statistically significant.

Results: A total of 464 participants were included. Overall, 28.7% of respondents rated their SAP knowledge as “good,” ranging from 21.9% among residents to 80% among professors (p<0.001). Guideline-concordant antibiotic selection was reported by 70.7% of participants; however, in cranial procedures, ceftriaxone was preferred over cefazolin in 56.2% of cases. Adherence to recommended timing of prophylaxis initiation was reported by 62% of participants, while 68.1% administered additional intraoperative doses during prolonged surgeries. Only 51.7% considered patient body weight when adjusting doses, and 37.9% reported discontinuing prophylaxis within 24 hours postoperatively. Professors demonstrated higher adherence across several parameters, including initiation timing, dosing, and discontinuation (all p<0.05).

Conclusion: Adherence to key components of SAP remains suboptimal among neurosurgeons in Türkiye. Although knowledge levels varied across academic ranks, this did not consistently translate into clinical practice. Structured educational initiatives, institutional protocols, and audit-based interventions may help improve adherence to guideline-recommended SAP practices.

Keywords: Surgical antimicrobial prophylaxis, neurosurgery, guideline adherence; cross-sectional survey

Objective: Rapid and accurate identification of central nervous system (CNS) pathogens is essential for appropriate antimicrobial management. This study aimed to evaluate the performance of the BioFire FilmArray Meningitis/Encephalitis (ME) Panel in comparison with conventional cerebrospinal fluid (CSF) analysis.

Materials and Methods: This retrospective study was conducted in a tertiary care hospital over a three-year period. A total of 1,470 CSF samples were analyzed using routine microbiological methods (culture and Gram staining), cytological examination, biochemical testing, and multiplex PCR with the BioFire FilmArray ME Panel.

Results: Pathogens were detected in 104 samples (7.1%), including 58 viral agents, 39 bacterial agents, one fungal agent, and six co-infections. Culture positivity was observed in one Streptococcus pneumoniae case and one Cryptococcus neoformans case, both concordant with PCR findings. Bacterial infections were associated with significantly lower CSF glucose levels (42.57 ± 26.07 mg/dL) and higher Lactate dehydrogenase (LDH) levels (320.33 ± 455.76 IU/L) compared with viral infections (60.38 ± 18.88 mg/dL and 53.08 ± 26.85 IU/L, respectively). Polymorphonuclear leukocyte (PMNL) predominance was significantly higher in bacterial cases. Receiver operating characteristic (ROC) analysis demonstrated good discriminatory performance for LDH (AUC = 0.835) and PMNL% (AUC = 0.822). Viral pathogens were more frequent in the 0–2-year age group, whereas bacterial infections predominated in older children.

Conclusion: The FilmArray ME Panel, when interpreted together with routine CSF biochemical and cytological parameters, provides a rapid and reliable diagnostic approach for differentiating bacterial and viral CNS infections.

Keywords: Cerebrospinal fluid, FilmArray multiplex PCR, meningitis/encephalitis, biochemical parameters.

Ventriculitis is a severe CNS infection with high mortality. We present a 24-year-old male with nasopharyngeal carcinoma who developed Klebsiella pneumoniae ventriculitis during hospitalization. Symptoms included fever, headache, and altered mental status. Due to acute hydrocephalus, an external ventricular drain (EVD) was inserted; purulent CSF subsequently grew K. pneumoniae. Despite aggressive intravenous and intrathecal antibiotic therapy, the patient died from septic shock. This case highlights the rapid clinical deterioration associated with Gram-negative bacterial ventriculitis and the management difficulties in immunosuppressed oncological patients, emphasizing the critical nature of this rare but fatal complication.

Keywords: Nasopharyngeal carcinoma, Klebsiella pneumoniae, ventriculitis, cerebrospinal fluid, hydrocephalus

The integration of immune checkpoint inhibitor therapy in the field of medical oncology has shifted prognosis of multiple solid organ malignancies, though, such an advancement is not without significant adverse events referred as immune-related adverse events. A novel pattern of autoimmune-like hepatitis following certain medication exposures including statins, isoniazid, nitrofurantoin, anti-tumor necrosis factor-alpha therapy and minocycline has recently been defined. We hereby present a 66-year-old male patient with extensive-stage small-cell lung carcinoma (SCLC) who was inflicted by acute liver injury while undergoing a conjunction of atezolizumab therapy and isoniazid prophylaxis for latent tuberculosis. The patient subsequently developed hepatotoxicity which improved after a discontinuation of isoniazid therapy and administration of corticosteroids. The aim of this report is to contribute to the literature by presenting a rare case of grade IV immune-related hepatotoxicity under atezolizumab therapy in a patient receiving isoniazid prophylaxis for latent tuberculosis.

Keywords: Atezolizumab, small-cell lung cancer, immune-related hepatotoxicity.

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