ĐẶC ĐIỂM DỊCH TỄ, LÂM SÀNG VÀ HÌNH THÁI NẤM CỦA BỆNH NẤM DA ĐẦU DO DERMATOPHYTES TẠI BỆNH VIỆN DA LIỄU TRUNG ƯƠNG TỪ THÁNG 12/2024 ĐẾN THÁNG 5/2025

Abstract

Objective: To describe the epidemiological, clinical, and mycological characteristics of patients with tinea capitis caused by dermatophytes, based on direct microscopic examination using a 20% potassium hydroxide (KOH) preparation. Subjects and Methods: A cross-sectional descriptive study was conducted on 132 patients who presented and were diagnosed with tinea capitis caused by dermatophytes at the National Hospital of Dermatology and Venereology from December 2024 to May 2025. Results: The prevalence of tinea capitis caused by dermatophytes was higher in females than in males (54.5% vs. 45.5%), and most commonly affected children under 10 years of age (84.9%). The majority of patients resided in rural areas (72.7%), significantly higher than those from urban settings (27.3%). Regarding hygiene habits, 42.4% reported drying or toweling their hair after washing, while 57.6% tended to leave their hair damp. In terms of medical history, 65.9% had contact with cats, dogs, or other domestic animals, 34.1% had a previous history of tinea capitis, and 12.9% reported exposure to infected individuals or had family members affected at the same time. There was a statistically significant difference in age group and gender distribution among patients (p<0.05). Common clinical manifestations included scalp scaling (90.2%), hair breakage or hair loss (89.4%), and pruritus (58.3%). Scalp lesions were predominantly diffuse (76.5%), while localized lesions accounted for 23.5%. Direct microscopic examination using 20% KOH revealed that 65.2% of patients had fungal hyphae and/or spores both inside and outside the hair shaft, 18.9% had endothrix fungi, and 15.9% had ectothrix fungi. Conclusion: Tinea capitis caused by dermatophytes is commonly observed in young children. Scaling, hair loss, and itching are the predominant clinical features. The lesions are mostly scattered and strongly associated with exposure to domestic animals and environmental factors.