Tinea capitis: a retrospective epidemiological comparative study

Currently, a wide spectrum of retrospective studies regarding the incidence of TC among children and adults are available in the world literature, but none of them are comparative, aiming to distinguish etiological diversity depending on the different geographic areas.

This study aimed to investigate the epidemiology of TC in Plovdiv, Bulgaria and Thessaloniki, and Greece, and to compare the results and predominant etiological agents using retrospective comparative analysis for an 11-year time period.

The subjects included were selected from archives of the Mycological Laboratory of the University Dermatologic Clinic, University Hospital “St. George” Plovdiv, Bulgaria, and the Mycological Laboratory of the First Dermatology Department of Aristotle University Thessaloniki, Greece, by retrospective analysis of data from an 11-year time period (2004–2014). A total count of 374 children aged 0–18, with confirmed diagnosis of TC via direct mycological examination and culture were included (128 children from Plovdiv, Bulgaria, and 246 children from Thessaloniki, Greece). Samples were plated on Sabouraud agar, followed by species identification of the isolated colonies.

Our results demonstrate that the incidence of TC in the region of Bulgaria and Thessaloniki for the investigated period was lower than for the previously reported period. In Plovdiv, Bulgaria, it was 1.20 ± 0.09 % (n = 172 from a total count of 14,278 cases of mycoses), as the disease accounts for 23.10 ± 1.79 % of all mycological infections among the pediatric population and 0.36 ± 0.05 % (n = 49 from a total count of 13,724) among the adults patients in Plovdiv, Bulgaria. The incidence of the disease during the period 2004–2014 in Thessaloniki was 2.49 ± 0.15 % (n = 253 cases of TC from a total count of 10,168 mycoses), as it accounts for approximately 27.06 ± 1.47 % of mycological infections among the pediatric population in Thessaloniki, Greece, and 0.08 ± 0.03 % (n = 7 from a total count of 9259) of the population of adult patients with mycoses. Our study confirmed the presumption that M. canis is the leader among the causative agents in TC in children in both of the included countries, but its presence in the etiology of disease in adult patients was very low and nonsignificant. We categorically identified dominance of the female gender among the children with TC in Plovdiv, Bulgaria; while in Thessaloniki, Greece, the gender distribution had an almost equal ratio of males to females.

Our results suggest that the gender predisposition depends also on the investigated geographic region and the time of the study, rather than only on the causative pathogen and age.