# A High Estimated Prevalence of Onychomycosis Exists Among Danish Children

## TL;DR

This study estimates a 2.4% prevalence of onychomycosis among Danish children, suggesting it may be increasing.

## Contribution

The first study to estimate onychomycosis prevalence in Danish children, revealing a higher-than-expected rate.

## Key findings

- 2.4% of Danish children had onychomycosis, all caused by Trichophyton rubrum.
- Nail abnormalities were observed in 29 children, with 23 referred for further examination.
- The prevalence is higher than previously reported in other European countries.

## Abstract

The prevalence of onychomycosis among children is suspected to be increasing. The current global prevalence of paediatric onychomycosis ranges from 0% to 7.7%. Clinical observations in Denmark suggest the same but to our knowledge no study exists estimating the prevalence of onychomycosis among Danish children.

The aim of the study was therefore to estimate this prevalence.

Children and their siblings were included upon visiting the Paediatric Department, Zealand University Hospital, Roskilde, Denmark. The children and their legal guardian, if under the age of 15 years, were asked to answer a questionnaire, and the children had their finger‐ and toenails photographed. Children with nail abnormalities suggestive of onychomycosis were offered a referral to the Department of Dermatology, Zealand University Hospital, Roskilde, Denmark for clinical and mycological examination.

A total of 170 children with a mean age of 6.9 years were included. Ninety‐seven (57.1%) were boys and a total of 46.5% of the children were healthy. Twenty‐nine children had nail abnormalities, and 23 accepted a referral to the Department of Dermatology. Four children had onychomycosis, all caused by
T. rubrum
, resulting in an estimated prevalence of 2.4% (CI 0.6%–5.9%).

The estimated prevalence (2.4%) of onychomycosis among Danish children is higher than expected compared to other European countries, but larger studies are needed to validate these findings. This supports the suggestion of an increasing prevalence of paediatric onychomycosis.