Etiologies of olfactory dysfunction in a pediatric population: based on a retrospective analysis of data from an outpatient clinic

PURPOSE: Although the prevalence of olfactory dysfunction in children is thought to be lower compared to adults, little is known about the actual frequency of etiologies of smell dysfunction in children. Aim of the study was (i) to describe the epidemiology of olfactory dysfunction in a pediatric population and (ii) to compare the distribution of etiologies to adults. MATERIAL AND METHODS: Data of patients consulting a smell and taste clinic between 2000 and 2017 were retrospectively analyzed. Frequency of major causes of olfactory dysfunction was examined with a focus on the pediatric population. RESULTS: A total of 7153 patients (164 children) were included in the analysis. Most children presented with congenital olfactory dysfunction (67%), or head-trauma (12%). In contrast, the cumulative frequency of olfactory loss associated with sinonasal disorders or acute infections of the upper airways was 6%. The frequency of etiologies of olfactory dysfunction changed with age: While the frequency of patients with congenital anosmia decreased, the frequency of causes related to infections of the upper respiratory tract and idiopathic causes increased. CONCLUSION: About 2/3 of olfactory dysfunction in children are congenital while 1/3 is acquired. The frequency of etiologies causing olfactory dysfunction change significantly from children to an adult population.