Lakshminarasimhan Sindhuja1, Devi Dayal2,3, Kushaljit Singh Sodhi4, Naresh Sachdeva5, Anish Bhattacharya6. 1. Pediatric Endocrinology Unit, Department of Pediatrics, Postgraduate Institute of Medical Education and Research, Chandigarh, India. 2. Pediatric Endocrinology Unit, Department of Pediatrics, Postgraduate Institute of Medical Education and Research, Chandigarh, India. drdevidayal@gmail.com. 3. Pediatric Endocrinology & Diabetes Unit, Department of Pediatrics, Advanced Pediatrics Center, Postgraduate Institute of Medical Education and Research, Chandigarh, 160012, India. drdevidayal@gmail.com. 4. Department of Radiodiagnosis, Postgraduate Institute of Medical Education and Research, Chandigarh, India. 5. Department of Endocrinology, Postgraduate Institute of Medical Education and Research, Chandigarh, India. 6. Department of Nuclear Medicine, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
Abstract
BACKGROUND: Familial clustering in patients with permanent congenital hypothyroidism (CH) caused by thyroid dysgenesis (TD) has been reported in developed countries. There is no information on familial TD from developing countries. METHODS: A total of 312 first degree relatives belonging to 80 families of children with TD (group 1) and 40 families of age-matched normal children (group 2) were screened by thyroid ultrasonography, serum total thyroxine (T4) and thyroid stimulating hormone (TSH). RESULTS: Thyroid scintigraphy revealed agenesis in 78.7% of the patients, ectopic gland in 15%, and hypoplasia in 6.2%. The mean thyroid volumes were similar in parents and siblings of both groups. Eight (10.6%) mothers in group 1 were identified to have thyroid hypoplasia as compared with none in group 2 (P=0.03). Serum TSH was significantly higher in group 1 than in group 2 (P=0.004). Sixteen (7.8%) subjects (6 mothers, 5 fathers, and 5 siblings) in group 1 were found to have subclinical hypothyroidism as compared to none in group 2 (P<0.05). Four families were identified to have thyroid developmental anomalies and abnormal thyroid functions accounting for 5% of cases of familial TD in our cohort. CONCLUSION: Thyroid developmental anomalies and thyroid function abnormalities are more frequent in first degree relatives of children with TD as compared with a control population. These findings suggest that possibly there is a genetic component of TD in Indian patients.
BACKGROUND: Familial clustering in patients with permanent congenital hypothyroidism (CH) caused by thyroid dysgenesis (TD) has been reported in developed countries. There is no information on familial TD from developing countries. METHODS: A total of 312 first degree relatives belonging to 80 families of children with TD (group 1) and 40 families of age-matched normal children (group 2) were screened by thyroid ultrasonography, serum total thyroxine (T4) and thyroid stimulating hormone (TSH). RESULTS: Thyroid scintigraphy revealed agenesis in 78.7% of the patients, ectopic gland in 15%, and hypoplasia in 6.2%. The mean thyroid volumes were similar in parents and siblings of both groups. Eight (10.6%) mothers in group 1 were identified to have thyroid hypoplasia as compared with none in group 2 (P=0.03). Serum TSH was significantly higher in group 1 than in group 2 (P=0.004). Sixteen (7.8%) subjects (6 mothers, 5 fathers, and 5 siblings) in group 1 were found to have subclinical hypothyroidism as compared to none in group 2 (P<0.05). Four families were identified to have thyroid developmental anomalies and abnormal thyroid functions accounting for 5% of cases of familial TD in our cohort. CONCLUSION: Thyroid developmental anomalies and thyroid function abnormalities are more frequent in first degree relatives of children with TD as compared with a control population. These findings suggest that possibly there is a genetic component of TD in Indian patients.