Decoding the missing link in cystic lung disease: a unique case series of BHD syndrome

<p><strong>Background:</strong> Birt-Hogg-Dubé syndrome (BHDS) is a very rare autosomal dominant inherited disease caused by mutations in the folliculin gene, characterized by a triad of clinical manifestations involving the skin, lungs, and kidneys.<br /><strong>Cases Presentation:</strong> We present a case series of four cases of BHDS with diverse phenotypic spectrum. Case 1 is a 48-year-old female who presented with right-sided hydropneumothorax and a typical triad of BHDS-cystic lung disease, fibrofolliculoma, and renal mass. Case 2 is a 31-year-old young male who presented with left-sided pneumothorax and cystic lung disease with no other systemic involvement. Case 3 is a 43-year-old female who presented with recurrent left-sided pneumothorax and cystic lung disease with no other systemic clinical manifestations. This particular case had a family history of pneumothorax. Case 4 is a 69-year-old female who presented with a chronic cough and right middle lobe pneumonia. She had typical nodular and papular skin lesions over the forehead and computed tomography-thorax showing bilateral cysts of varying size.<br /><strong>Conclusion:</strong> This case series highlights the diverse clinical spectrum of BHDS, emphasizing the importance of early recognition of this condition in patients with recurrent pneumothorax, genetic confirmation of the disease, and multidisciplinary management, including nephrology and pulmonology inputs to prevent complications such as recurrent pneumothorax and renal malignancies. Further research on genotype-phenotype correlation in BHDS is needed to optimize the diagnosis and treatment.</p>