Eruptive Vellus Hair Cysts in a Patient with Lowe Syndrome

: We present a 20‐year‐old patient with Lowe syndrome and eruptive vellus hair cysts. Also known as oculocerebrorenal syndrome, it is an X‐linked recessive disorder localized to Xq24‐26.1. The phenotypic features of this disorder are Fanconi‐type renal failure, mental retardation, and various eye abnormalities. The causative gene, oculocerebrorenal‐Lowe 1 (OCRL1), encodes a phosphatase whose function is to regulate the phosphatidylinositol pool of intracellular signaling molecules that regulate the release of lysosomal enzymes in tissues. Low levels of this phosphatase lead to the extracellular release of lysosomal enzymes in organs such as the eye, brain, and kidney, with the resulting tissue damage most likely accounting for the characteristic phenotype. Our patient with Lowe syndrome had several discrete, dome‐shaped papules on his midchest. They clinically resembled either eruptive vellus hair cysts or steatocystoma multiplex. Histologically they were most diagnostic of eruptive vellus hair cysts, which are not a known feature of Lowe syndrome. We present a hypothesis based on the known biochemical deficiencies resulting from the mutations in the OCRL1 gene, which may account for the cyst formation. To our knowledge, this is the first reported case of skin findings associated with this disorder.