Pulmonary function in Williams-Beuren syndrome: Spirometric data of 22 Italian patients

Williams-Beuren syndrome (WBS) is caused by an haploinsufficiency of the 7q11.2 region which involves the elastin gene (ELN). A deficiency of elastin is a known pathophysiological mechanism of emphysema/chronic obstructive pulmonary disease (COPD). A previous study hypothesized a higher risk of COPD in WBS patients. Herein, this phenomenon was further investigated looking for a possible correlation between COPD and WBS. Dynamic lung volumes (forced vital capacity [FVC], FEV1, FEV1/FVC) were measured in 22 patients (age range 18.9 ± 7.4 years) affected with WBS, genetically confirmed, correlating these parameters to respiratory risk factors. Dyspnea, cough and wheezing were detected in 6/22 (27%) patients. Obstructive and restrictive patterns were identified in 6/22 (27%) and 2/22 (9%) cases, respectively with no evidence of irreversible obstruction. CVF, FEV1 and FEV1/CVF mean values were all normal, with values of 91.3% (n.v. > 80%), 84.2% (n.v. > 80%) and 0.82 (n.v. > 0.7), respectively. The severity of the comorbidities did not show a cause-effect relation with the respiratory patterns, nevertheless patients treated with anti-hypertensive drugs had poorer pulmonary function. Our findings are in accordance with previous observations, showing that emphysema/COPD is not a typical finding in young patients with WBS. However, a respiratory function assessment should be included in the follow-up of WBS patients, especially in adolescents/young adults under treatment with anti-hypertensive drugs.