A systematic review and meta-analysis on the epidemiology, casual agents and demographic characteristics of onychomycosis in Iran

Abstract Onychomycosis or fungal nail infection is one of the most common fungal infections. Nearly 50% of all nail disorders are caused by fungi. This systematic review and meta-analysis was conducted to determine the prevalence of onychomycosis across Iran. We searched English and Persian databases for studies reporting the epidemiologic features of onychomycosis in Iranian people from January 2000 to December 2018. Literature search revealed 307 studies, of which 24 studies met the eligibility criteria. In order to identifying the existence of publication bias among studies, funnel plots were used. The results of the meta-analysis were visualized as a forest plot representing the prevalence estimates of each study. Heterogeneity was also analyzed using the I 2 , Chi 2 , and Tau 2 statistics. A high level of I 2 and Chi 2 was obtained among studies, which provides evidence of notable heterogeneity between studies. The results of current study revealed that the highest prevalence of onychomycosis was related to Mazandaran and Tehran provinces, respectively. As in the literature hypothesized shift in etiologic agents from yeasts to dermatophytes or molds could not be confirmed. Females were affected more frequently than males and in both sexes the highest incidence of infection occurrence was at the ages of > 50 years. It seems the highest prevalence of onychomycosis in Mazandaran and Tehran provinces is due to the concentration of specialist doctors and research centers in these two provinces compared with others which leads to more detection and more care of the disease. Therefore, further educational strategies in order to accurate diagnosis in other provinces is necessary to reduce the risk of onychomycosis in Iran.