[Familial pulmonary cysts and papular skin lesions in a 37-year-old woman].

A 37-year-old female patient presented with sudden dyspnea and chest pain. Spontaneous pneumothoraces had been observed several times before in this patient and two members of the patient´s family in the last years. Moreover, she exhibited papular facial skin lesions. Radiomorphologically a pneumothorax apical on the left side and basal accentuated cystic lung destruction on both sides could be seen. Pleurodesis and several wedge resections with insertion of a drainage on the left side were performed therapeutically. Histology disclosed multiple cysts, whereby typical differential diagnoses could be excluded by immunohistochemistry. A molecular genetic investigation detected a heterozygous mutation in the gene coding for follikulin (FLCN). Thereby, Birt-Hogg-Dubé syndrome (BHDS) was diagnosed. BHDS follows autosomal dominant inheritance and is characterized by cystic lung lesions with recurrent pneumothoraces, cutaneous fibrofolliculomas and an increased risk of renal carcinomas. It is based on mutations in the gene coding for the protein FLCN on chromosome 17.