Over the past few years there have been several reports concerning the variation in BHD symptom presentation in Asian populations compared to western populations. Although up to 90% of western BHD patients present with the classic fibrofolliculomas, the incidence of such dermatological involvement is rarer in Asian patients – only 20-27%. In contrast the likelihood of presenting with a pneumothorax is significant greater in these populations with reportedly up to 90% of cases developing at least 1 pneumothorax and the majority more (Kunogi et al., 2010). Therefore if pulmonologists are unaware of the syndrome the correct diagnosis of BHD may be particularly low in these populations. Increasing awareness of BHD as a potential cause of pneumothorax could help more families be identified and therefore begin screening for renal tumours.
A recently published case study from Muira et al., (2015) reported the diagnosis of BHD in a young woman who presented with asymptomatic, bilateral pneumothoraces. Although there was a strong family history of pneumothorax, neither she nor her family had any renal or dermatological involvement. A CT scan identified cysts on both lungs and LAM was ruled out following histological examination on these cysts. Genetic testing identified a deletion mutation in her FLCN gene (c.1379-1380 delTC) that has previously been reported. Although, based on family history, her risk of renal tumour development is deemed to low based, the diagnosis of BHD will enable early detection of any developing tumours due to regular monitoring.
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