Birt-Hogg-Dubé syndrome: a case series highlighting pulmonary manifestations, rare renal involvement and role of familial diagnosis; [Birt-Hogg-Dubé sendromu: Pulmoner semptomları, nadir böbrek tutulumunu ve ailesel geçisin rolünü vurgulayan bir vaka serisi]

Abstract

Birt-Hogg-Dubé syndrome: A case series highlighting pulmonary manifestations, rare renal involvement and role of familial diagnosis Birt-Hogg-Dubé syndrome (BHDS) is a rare autosomal dominant disease characterized by cutaneous lesions and renal tumors, along with the presence of pulmonary cysts. In most cases, it is caused by a mutation in the folliculin (FLCN) gene. While normally evaluated as a triad, the isolated pulmonary presentation can still be expected, and repeated pneumothorax history should be evaluated for BHDS, especially if it is present in family members. In this case series, three patients with different clinical findings were reported. The first patient had a repeated pneumothorax history, along with angiomyolipoma, a relatively unexpected presentation of renal BHDS involvement. The incidental presence of pneumothorax in his mother had strengthened the diagnosis of BHDS, for which she also had renal cysts and additional cutaneous lesions. While these two patients were evaluated on an inpatient basis, the third patient, the son of the first patient, had been evaluated for BHDS presence, and pneumothorax, along with pulmonary cysts, was observed. All three patients were then later referred to a genetic center for confirmation of the FLCN mutation and tested positive for it. These case series illustrate the possibility of a different clinical presentation within the same family and at different ages, along with rare renal presentation and the possible asymptomatic indolent nature of the disease. © 2025 by Tuberculosis and Thorax.