Comedonal and Cystic Fibrofolliculomas in Birt-Hogg-Dube Syndrome.

IMPORTANCE: The differential diagnosis of extensive open comedones includes inherited genetic syndromes and several acquired conditions. Birt-Hogg-Dube syndrome (BHD) is not typically included in the differential diagnosis of syndromes with comedonal lesions. Given the potentially life-threatening systemic complications associated with BHD, early recognition and diagnosis of the condition is important. OBSERVATIONS: We describe comedonal or cystic fibrofolliculomas in 4 patients with BHD. Cutaneous lesions were identified on the face, neck, chest, and abdomen. CONCLUSIONS AND RELEVANCE: Comedonal or cystic fibrofolliculomas are a variant of fibrofolliculomas that have not previously been well characterized in patients with BHD and represent a novel diagnostic clue to its early detection and diagnosis. Expanding the phenotypic features of BHD facilitates earlier diagnosis of the syndrome, which allows for early surveillance of renal cancer in affected patients as well as disease screening in their relatives.