Thyroid abnormalities among first-degree relatives of children with congenital hypothyroidism: An ultrasound survey

Background: Congenital hypothyroidism (CH) is caused by thyroid dysgenesis and dyshormonogenesis. Evidence suggests the presence of genetic factors in both types of pathogenesis. We investigated whether an increased incidence of thyroid abnormalities could be shown by ultrasonography among first-degree relatives of children with CH. Material and Methods: In this case-control study the presence of both developmental and non-developmental thyroid abnormalities was studied among first-degree relatives of CH patients and healthy children. Assessments included neck ultrasonography and thyroid function tests. The data obtained from parents, siblings and children were compared in the case and control groups. Results: In the case group, 92 patients, 172 parents and 57 siblings, and in the control group, 82 healthy children, 160 parents and 39 siblings were studied. Thyroid developmental abnormalities were more prevalent among parents (3.5 vs. 0%, p = 0.03) and siblings (10.5 vs. 0, p = 0.01) of CH patients than the control group. Non-developmental abnormalities were not significantly different between the case and control groups (17 vs. 13%, p = 0.3). Conclusion: Thyroid developmental abnormalities were more prevalent among parents and siblings of CH patients than the control group, confirming the familial component of this entity. Copyright (C) 2008 S. Karger AG, Basel.