غربالگري نوزادان براي شناسايي كم كاري مادرزادي تيروييد در رشت

Neonatal Screening for Congenital Hypothyroidism (CH) in Rasht

Introduction: Early diagnosis and treatment of congenital hypothyroidism before 6 weeks of birth and preferably at birth, prevents brain damage. Neonatal screening for CH is carried out routinely in developed countries. Overall, the incidence of CH is 1.4000 infants in average. The incidence is higher in iodine deficient areas; also more transient TSH elevation is observed in these districts. Objective: This study was conducted to clarify thyroid dysfunction in the neonates born in Rasht Alzahra Hospital, after elimination of Iodine deficiency in the province. Materials and Methods: All the newborns, up to 3000 neonates, born in one year were included in the study. TSH was measured in cord blood serum immediately after birth by IRMA method. TSH 20 mU/L was considered abnormal. Venous sampling for TSH & T4 was done on recalled patients. Neonates with T4 and TSH measurements <6.5 kg/dL & >10 mU/L respectively or TSH> 30 mU/L alone were considered hypothyroid. Hypothyroid neonates were evaluated for renal and cardiac anomalies by sonography and echocardiography. Results: 62 neonates had TSH>20 mU/L. The mean of cord blood TSH was 32.5 mU/L, with a range of 20-123 mU/L. in recall, only 2 cases (one girl, one boy) had elevated TSH (TSH>l0mu/L) and were considered hypothyroid. None of them had clinical findings of hypothyroidism, goiter and congenital anomalies. Conclusion: With respect to the high incidence of CH and transient TSH elevation (57 cases, 1.9%), supervision on production and consumption of iodide salts via periodic screening of population for iodine deficiency and neonatal screening for CH is strongly suggested.