Abstract
Steatocystoma multiplex (SM) is a rare disorder of the pilosebaceous unit characterized by the eruption of numerous sebum-containing dermal cysts. Most cases are sporadic; how-ever, familial cases with autosomal dominant inheritance have also been described.
The aetiopathogenesis of SM remains elusive but there are several hypotheses to explain its cause, such as it originating from sebaceous retention cysts, or representing a naevoid malformation of the pilosebaceous duct. Surgical removal and decapitation of the cyst surface are the most frequently applied therapeutic options.
Mutations in the keratin 17 (K17) gene (KRT17) have been repeatedly reported for familial cases of SM. K17 is a type I keratin expressed in a number of epidermal appendages, such as the nail bed, hair follicles and sebaceous glands.
Here, we present a family comprising five affected individuals with SM with remarkably varying severity.