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A Case of Birt-Hogg-Dubé Syndrome: A Rare but Essential Diagnosis to Consider
Andrew Hong1, Kevin Eng2,3, Jaime Betancourt2,3
1University of California, Los Angeles.
Background:
Birt-Hogg-Dubé syndrome (BHD) is an autosomal dominant disorder characterized by multiple pulmonary cysts, predisposing individuals to spontaneous pneumothorax, cutaneous lesions-specifically fibrofolliculomas-and an increased risk of renal malignancies. Although diagnosing BHD is difficult due to the variable presentation of the disease, identification is crucial for proper management, which includes lifelong screening for renal malignancies and management of recurrent pneumothoraces. Despite its rarity, maintaining awareness of BHD in the differential diagnosis of pulmonary cysts is essential.
Case Presentation:
We present the case of a nonsmoking male veteran in his 60s whose BHD diagnosis surfaced many years after a history of recurrent pneumothoraces, leading to 1 pleurodesis in each lung. Genetic testing of the FLCN gene confirmed the BHD diagnosis. A shave biopsy of a skin lesion confirmed a histologic pattern of fibrofolliculoma/trichodiscoma. Annual magnetic resonance imaging surveillance was initiated to monitor for potential renal malignancies.
Conclusions:
BHD is a rare and complex disease. Early recognition and diagnosis play a pivotal role in preventing potentially severe complications such as renal malignancies. Suspicion for a genetic disorder such as BHD, lymphangioleiomyomatosis, or pulmonary Langerhans cell histiocytosis should arise in patients who experience spontaneous pneumothorax, especially in the presence of multiple cystic lesions or a family history of pneumothoraces. Early consideration of pleurodesis after the first spontaneous pneumothorax is recommended. The complex presentation of BHD may delay recognition, which can be exacerbated by variable continuity of care.
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