Clinical and epidemiological characteristics of tinea capitis in northern Taiwan during 2014-2019: An unusual bimodal distribution of patients and comparison of paediatric and adult cases

Tinea capitis (TC) mainly occurs in children, and related studies in adults are rare. We aimed to investigate the current epidemiological, clinical and mycological characteristics of TC and to compare adult and paediatric patients in northern Taiwan. We conducted a retrospective study at Chang Gung Memorial Hospital, Linkou Branch, from 2014 to 2019. The dataset included age, sex, records of underlying diseases, animal contact history, frequent hair salon visits, clinical patterns, treatment and outcome via chart or phone call reviews. The average ages of 72 children and 104 adults recruited were 6.0 and 74.0 years, respectively. A female predominance was noted in both groups, and the ratio of females was significantly higher in adults (94.2% vs 59.7%, P <.0001). Microsporum canis (76.4%) and Trichophyton mentagrophytes (11.1%) in children, and M. canis (49.0%) and T. violaceum (31.7%) in adults were the most common pathogens. Adults were more likely to be infected with T. violaceum (OR = 10.14, 95% CI = 2.04-50.26) than children. In contrast, adults were less likely to be infected with M. canis than children (OR = 0.31, 95% CI = 0.11-0.90). Furthermore, adults visited hair salons more, had less animal contact and were more immunosuppressed than children. TC is not unusual in the adult population. Dermatologists are advised to realise risk factors such as immunosuppression and regular hair salon visit in adult TC.