OBJECTIVE: To study the prevalence of congenital hypothyroidism in infants with Down's syndrome and to verify whether there is an association with other congenital defects. METHODS: This is a prospective study of 112 Down patients, less than 1 year of age, who attended Songklanagarind Hospital from January 1991 to December 1996. Free T4 and TSH determinations were performed in all Down infants. Information on karyotype, sex, maternal age and other congenital anomalies was collected. RESULTS: Congenital hypothyroidism was detected in 17 patients (15.2%); 3 overt congenital hypothyroidism; 6 persistent compensated hypothyroidism; and 8 transient compensated hypothyroidism. Nine of the 20 patients (45%) with congenital gastrointestinal anomalies had congenital hypothyroidism, while 8 out of 92 patients (8.7%) without congenital gastrointestinal anomalies had congenital hypothyroidism. The odds ratio was 8.59 (95% confidence interval 2.4-31.6; p = 0.0001). CONCLUSION: Congenital hypothyroidism has a relatively high prevalence rate in Down infants and tends to occur in Down patients with gastrointestinal anomalies.
OBJECTIVE: To study the prevalence of congenital hypothyroidism in infants with Down's syndrome and to verify whether there is an association with other congenital defects. METHODS: This is a prospective study of 112 Down patients, less than 1 year of age, who attended Songklanagarind Hospital from January 1991 to December 1996. Free T4 and TSH determinations were performed in all Down infants. Information on karyotype, sex, maternal age and other congenital anomalies was collected. RESULTS:Congenital hypothyroidism was detected in 17 patients (15.2%); 3 overt congenital hypothyroidism; 6 persistent compensated hypothyroidism; and 8 transient compensated hypothyroidism. Nine of the 20 patients (45%) with congenital gastrointestinal anomalies had congenital hypothyroidism, while 8 out of 92 patients (8.7%) without congenital gastrointestinal anomalies had congenital hypothyroidism. The odds ratio was 8.59 (95% confidence interval 2.4-31.6; p = 0.0001). CONCLUSION:Congenital hypothyroidism has a relatively high prevalence rate in Down infants and tends to occur in Down patients with gastrointestinal anomalies.