Status of the Microbiological Isolates and Antibiotics Susceptibilities in Patients with Auricular Perichondritis.

Abstract

Auricular perichondritis is a dangerous infection involving the external ear cartilage and its perichondrium. This condition can lead to significant morbidity including cartilage necrosis, deformity and the characteristic "cauliflower ear" if not properly diagnosed and treated in a timely manner. The infection typically develops following trauma, burns, insect bites, ear surgery, or ear piercings through the cartilaginous portion of the ear. Objective of the study was to analyze the microbiological profile and antibiotic susceptibility patterns in auricular perichondritis and to evaluate treatment outcomes in relation to causative organisms and therapeutic approaches. This prospective observational study of 50 consecutive cases of auricular perichondritis was conducted at Mymensingh Medical College Hospital from July 2022 to June 2023. Specimens were collected for culture and antimicrobial susceptibility testing. Patient demographics, predisposing factors, clinical presentations, treatment modalities, and outcomes were analyzed. Patients were followed up for 30 days post-treatment. The mean age was 28.3±9.7 years, with male predominance (60.0%). Ear piercing was the most common predisposing factor (56.0%). Culture positivity rate was 86.0%, with Pseudomonas aeruginosa (41.9%) and Staphylococcus aureus (27.9%) being the predominant isolates. Methicillin-resistant Staphylococcus aureus (MRSA) accounted for 11.6% of isolates. Pseudomonas (P.) aeruginosa showed high susceptibility to fluoroquinolones (88.9%) and aminoglycosides (83.3-94.4%). Complete clinical resolution was achieved in 94% of cases, with mean treatment duration of 14.2 ± 3.8 days. Delayed presentation (>3 days) significantly correlated with complications (p=0.023). The study reveals evolving patterns of causative organisms in auricular perichondritis, with a notable presence of resistant organisms. High culture positivity rates support the importance of culture-guided therapy. Treatment outcomes are favorable with appropriate antibiotic selection and timely intervention. These findings provide evidence-based parameters for empiric therapy while emphasizing the importance of microbiological confirmation.