The lungs were divided into upper and lower zones at the level of the right main pulmonary artery.
There is no existing rating system for cystic lung disease.
Lung function testing, including spirometry and diffusing capacity for carbon monoxide (DLCO), was performed in accordance with ATS standards and using the well-validated Knudson 1983 normset .
Lung function tests performed at the time of the individual’s BHD diagnosis were used for data analysis.
All those with confirmed BHD were offered a clinical assessment by the Medical Genetics and Pulmonary services which included a history, physical exam, complete pulmonary function tests, and computed tomography (CT) scan of the chest and abdomen. Of these, 100 % (28/28) had pulmonary cysts, 41 % (13/32) had spontaneous pneumothoraces, 26 % (8/31) had kidney cysts, 3 % (1/31) had renal tumors, and 53 % (18/34) had dermatologic manifestations. Cyst size (OR 3.23, 95 % CI 1.35–7.73) and extent of lower lung zone disease (OR 6.43, 95 % CI 1.41–29.2) were the only findings associated with pneumothorax.
The size or extent of cystic disease did not correlate with lung function results.
** Referral to Medical Genetics refers to a formal appointment to review patient clinical history (genetic testing may have been performed in individuals due to family history with their consent in the absence of formal appointment Medical Genetics appointment with functional inquiry) . The average age at diagnosis was 42 years (range of 19–71 years).