Birt-Hogg-Dubé Syndrome: Another mTOR Phenomenon


      Birt-Hogg-Dubé syndrome is an uncommon autosomal dominant systemic disorder with cutaneous findings notable for fibrofolliculomas or trichodiscomas on the scalp, face, neck, and trunk. These cutaneous signs are associated with bilateral renal cell carcinoma, benign renal cysts, pulmonary cysts, and spontaneous pneumothorax. Given its autosomal dominant inheritance pattern, the successful diagnosis of BHDS may elucidate a diagnosis in family members. BHDS results from a mutation in the FLCN gene encoding the folliculin protein, a transcriptional regulator of the mammalian target of rapamycin (mTOR) signaling pathway. Like tuberous sclerosis, BHDS's clinical features may subside with the use of oral rapamycin for mTOR inhibition, a theoretical concept meriting exploration. Although its prevalence in the general population has been estimated at only 2 cases per million, BHDS has been detected in a few patients from the nearby Portuguese-lineage quarter of the city of Newark, a disproportionate prevalence possibly explained by the founder effect.

      Key Words

      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'


      Subscribe to Clinics in Dermatology
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect