Case Presentation: We report a case of a 49-year-old Caucasian male presenting with sudden chest pain worsened by inspiration. Patient reports Birt-Hogg-Dubé Syndrome (BHDS) diagnosis via skin biopsy 5 years ago. Examination is significant for 2-4 mm flesh-colored, dome-shaped papules on the head and neck. No murmurs, chest wall tenderness, wheezing or rhonchi were appreciated. Patient was afebrile and vitals were stable. EKG did not show ischemic changes. Troponin levels were 0.00. CT chest with contrast showed a small left pneumothorax, emphysematous lungs with scattered atelectasis, and ground-glass opacities bilaterally. General surgery recommended no intervention for the small pneumothorax. A pulmonologist recommended symptomatic treatment with cough suppressants to prevent bleb rupture. CT abdomen/pelvis showed a 2.2 cm mass on the right mid kidney.
Discussion: BHDS is a rare autosomal dominant disorder involving the folliculin (FLCN) gene on chromosome 17. FLCN is a tumor suppressor gene that regulates cellular proliferation. BHDS has a highly heterogenous phenotype, and is characterized by cutaneous fibrofolliculomas, pulmonary cysts, spontaneous pneumothorax, and a sevenfold increased risk of renal carcinoma (1). Diagnosis of BHDS relies upon clinical suspicion and is confirmed with DNA sequencing. With only 200 families diagnosed with BHDS worldwide (2), our objective is to increase clinical awareness of BHDS and improve patient prognosis through early diagnosis and management. The predisposition to renal carcinoma is the most feared complication of BHDS with a morbidity rate of 27-34% in Caucasian populations (3). Therefore, prognosis is critically dependent upon radiologic surveillance and early diagnosis for renal carcinoma to limit metastatic disease. Based on medical literature, our case confirms all of the long-term clinical manifestations of BHDS.
Conclusions: We recommend annual abdominal/pelvic MRI or CT with contrast to screen for renal carcinoma. In addition, an increased risk of melanoma from from skin lesions indicates dermatologic examination every 6-12 months. BHDS treatment is dependent upon severity, and may involve laser ablation for fibrofolliculomas, pneumothorax therapy, and nephrectomy for severe renal carcinoma. Finally, we recommend genetic screening for BHDS in patients with a history of renal carcinoma and spontaneous pneumothorax without another plausible etiology. Due to the rarity of BHDS, increased clinical awareness and detection is necessary to facilitate early diagnosis and proper management.