A cross-sectional study examining the prevalence of antibiotic-resistant Cutibacterium acnes isolated from patients with acne in Bangkok, Thailand.

Cutibacterium acnes is associated with the pathogenesis of acne vulgaris (AV). The relationship between antibiotic-resistant C. acnes and AV remains unclear. The authors aimed to determine the prevalence of antibiotic-resistant C. acnes and investigate the association of acne severity with topical and systemic treatments in patients with acne. Samples were collected of inflammatory and noninflammatory acne, including closed and open comedones and erythematous papules/pustules from the face of patients with mild to severe acne. The samples were cultured under anaerobic conditions for the isolation of C. acnes. Antibiotic susceptibility tests for erythromycin, tetracycline, doxycycline, clindamycin, and trimethoprim/sulfamethoxazole were performed using the agar dilution method. From 153 patients, 143 viable C. acnes samples were isolated (93.5%). They were found resistant to trimethoprim/sulfamethoxazole (143/143, 100%), clindamycin (108/143, 75.5%), erythromycin (105/143, 73.4%), tetracycline (74/143, 51.7%), and doxycycline (73/143, 51.1%). There was no significant correlation between the prevalence of antibiotic resistance and acne severity. High-level resistant C. acnes correlated with higher clinical severity of acne in patients taking doxycycline (τ  = 0.3). The present prevalence of antibiotic-resistant C. acnes was high in Thailand. Antibiotic stewardship in AV treatment should be encouraged to prevent further antibiotic resistance crises.