Clinical diagnosis and genetic testing for Pendred syndrome

YUAN Yongyi; HUANG Shasha; ZUO Lujie; ZHANG Guozheng; DAI Pu

doi:10.3969/j.issn.1672-2922.2014.01.004

Abstract：Objective To analyze the clincial traits and genetic testing for Pendred syndrome and tohelp ENT doctors understand the disease and avoid misdiagnosis and missed diagnosis. Methods 1,745 patients with enlarged vestibular aque-duct verified by high resolution temporal bone CT scan were included. After careful physical examination, ultrasound scan of thyroid, thyroid hormone assays and the perchlorate discharge test were performed on subjects with bilateral EVA and goiter. Results Pendred syndrome was diagnosed in four patients. They all showed goiter, sensorineural hearing loss and EVA. The goiter all appeared after 11 years old in these Pendred syndrome patients. Three of them were verified thyroid iodine organifi-cation defect by perchlorate discharge test. The thyroid hormone levels were all within the normal range. PDS gene sequenc-ing was carried out in 3 of the Pendred syndrome patients and these patients were all found carrying homozygous or compound heterozygous PDS mutations. Conclusions Since the phenotype of goiter didn’t emerge at the time the Pendred syndrome patients came to the clinic, or the doctors hadn’t enough experience on Pendred syndrome, there are still missed diagnosis on the disease in China. And the ratio of Pendred syndrome may be not so low as that shown by our study. We suggest that chil-dren EVA patients should be given instruction for follow-up of the thyroid. Genetic testing is one of the major factors for diag-nosing Pendred syndrome. It’s important for the normal hearing parents who had given birth to a Pendred syndrome baby and are in need of repregnancy. It’s also significant for Pendred syndrome patients in need of genetic counseling before marriage and pregnancy.