Abstract
OBJECTIVE: Tinea capitis, a chronic inflammatory disease of the scalp and hair shafts caused by dermatophyte infections, manifests clinically as erythematous lesions, scaling, alopecia, and pustule formation. Hainan, a tropical island province in China, exhibits distinctive climatic conditions and demographic contact patterns that could shape its pathogen spectrum. However, comprehensive epidemiological data remain scarce. This study analyzes the epidemiological characteristics and pathogen spectrum of tinea capitis in Hainan, China. METHODS: This study was undertaken across 11 coastal and inland dermatological centers in Hainan Province (January 2023 to December 2024). A total of 76 tinea capitis patients diagnosed via mycological examination (fungal fluorescence microscopy, fungal culture with species identification) and corroborated by dermatoscopic evaluation were consecutively enrolled. Data on demographic characteristics, exposure history, and clinical manifestations were systematically collated using standardized case report forms. Pathogen subtyping was performed via integrated morphological identification supplemented by molecular biological analysis of the ITS region. RESULTS: Among 76 enrolled patients, minors (≤15 years) accounted for 80.26% (61/76), with ≤10-year-olds representing 91.8% (56/61) of pediatric cases. The overall male-to-female ratio was recorded as 1:1.05 (37 males vs. 39 females), while pediatric patients (≤15 years) exhibited a 1.07:1 ratio (31 males vs. 29 females). Animal contact history was reported in 31 cases (40.79%), scalp trauma in 3 cases (3.95%), and co-occurring superficial fungal infections in 12 cases (15.79%). Fungal elements were detected via direct microscopic examination in 64 cases (84.21%). Fungal cultures obtained 45 positive isolates (19 strains in 2023, 26 in 2024), with kerion (inflammatory tinea capitis) exhibiting the highest culture positivity rate, followed by tinea alba. The primary pathogens identified were zoophilic Microsporum canis (M. canis) (20 cases, 43.79%) and anthropophilic Trichophyton rubrum (T. rubrum) (9 strains, 19.57%). Clinical manifestations comprised kerion (44 cases, 57.89%), tinea alba (27 cases, 35.53%), and black dot tinea (5 cases, 6.58%). Kerion cases were predominantly linked to M. canis and T. mentagrophytes (interdigital subtype), whereas tinea alba demonstrated infections by M. canis and T. rubrum. Black dot lesions were additionally observed in M. canis infections. CONCLUSION: The primary affected group is children ≤10 years old, with the most common pathogenic fungus being zoophilic M. canis, and clinical classification is predominantly kerion. Dermatologists should pay attention to different transmission routes and pathogen spectra.