Birt-Hogg-Dube Syndrome

Birt-Hogg-Dube syndrome (BHDS) is a rare, complex, genetic disorder with three main clinical findings: non-cancerous (benign) skin tumors; lung cysts and/or history of pneumothorax (collapsed lung); and various types of renal tumors. Fibrofolliculomas are a type of benign skin tumor specific to BHDS. They typically occur on the face, neck, and upper torso. Most people with BHDS also have multiple cysts in both lungs that can be seen on high-resolution chest CT scan. While these cysts usually do not cause any symptoms, they put people at increased risk for spontaneous pneumothorax. BHDS is caused by mutations in the FLCN gene. The condition is inherited in an autosomal dominant fashion.