Abstract
Birt-Hogg-Dubé syndrome is a rare autosomal dominant disorder characterized by fibrofolliculomas, renal tumors, and lung cysts of varying sizes that exhibit a lentiform appearance. The cysts are typically small (less than 1 cm), thin-walled, and irregularly shaped, with a higher prevalence in the basal and mediastinal regions of the lungs. Approximately 30% of patients experience one or multiple pneumothoraces before reaching 40 years of age. Unlike in other cystic lung diseases, lung cysts in this condition do not show progression. Malignant renal tumors manifest in 12−35% of individuals before the age of 50, with surgical intervention being the preferred treatment option. As mortality frequently results from these renal tumors, expert consensus often advocated for screening starting at 21 years of age. Herein, we present a 68-year old male patient who presented with shortness of breath and cough. He had a history of pneumothorax 30 years ago. Computed tomography of the thorax revealed lentiform (lens-shaped) cysts of various sizes in the basal regions of the lungs. Since multiple fibrofolliculomas on the face and neck, Birt-Hogg-Dube sydrome was considered, and genetic screening was performed. A mutation in the Folliculin (FLCN) gene was identified. Abdominal Magnetic Resonance Imaging (MRI) was performed to assess for kidney tumors, but no pathology was identified. Although this patient does not have a renal tumor, we want to emphasize the need for MRI screening for renal tumors in patients with Birt-Hogg-Dube syndrome. Additionally, due to autosomal dominant inheritance, genetic screening is recommended for relatives.