Abstract
Williams-Beuren syndrome (WBS) is caused by microdeletions of 7q11.23, including the ELN gene, and the characteristic vascular lesions include supravalvular aortic stenosis (SVAS) and peripheral pulmonary artery stenosis (PPS). We identified a patient who has the characteristic cardiovascular lesions of WBS but does not have the 7q11.23 deletion: analysis of ELN identified a nonsense mutation. This case is a baby girl, whose cardiovascular abnormalities were not identified during fetal life. She was admitted with systemic cyanosis after birth, and was diagnosed with SVAS and supravalvular pulmonary stenosis (SVPS). At 10 months of age she underwent cardiac catheterization and confirmed SVAS, which was accompanied by a thin ascending aorta, PPS narrowing from hilar, and SVPS. Due to high blood pressure and hyperreninemia, she was diagnosed with renal vascular hypertension caused by bilateral renal artery stenosis identified on MDCT and began an oral carvedilol regimen. Mental retardation and malformations associated with WBS were not observed and a FISH analysis excluded a microdeletion encompassing ELN. Since mutations in ELN have been identified in cases of isolated SVAS it was screened and a novel nonsense mutation in Exon 24 was identified. Thus, the cardiovascular lesions were considered to be caused by elastin deficiency due to this ELN mutation. We suggest that if a patient has the characteristic cardiovascular lesions of WBS, but is FISH negative, then ELN should be screened for mutations.
