Etiology of congenital hypothyroidism among infants screen by the Philippine newborn screening program /
Ethel M. Estanislao [and four others]
OBJECTIVES: To determine the etiology of congenital hypothyroidism (CH) among infants screened by the Philipp Newborn Screening Program. This study also aims to compare the levels of TSH, T4 and developmental stato the infants among the different etiologies.
METHODOLOGY: From July 1996 to September 2004, 121 patients out of 371,072 babies screened were confirmed to have C Medical records were requested for review. Patients' demographics, maternal history, developmental status, a results of thyroid scan, TSH, T4 levels and bone age were collected. Thyroid status of the pregnant mother a developmental status of the offspring were examined. TSH, T4, and developmental status of the patients we compared among the different etiologies.
RESULTS: Of the 121 patients confirmed to have CH, only 42 (35 percent) clinical records were available for review. Among the < reviewed cases, the female to male ratio is 2:1. Athyreosis was seen in eleven infants (26 percent); seven infants (7 percent) h: hypoplastic glands; four (9 percent) had ectopic thyroid glands; two (5 percent) had enlarged glands; nine (21 percent) had norm gland dimensions and functional uptake; and nine (21 percent) had no data on thyroid imaging. Twenty-one percei (9/42) were offsprings of mothers with thyroid dysfunction during pregnancy. Seventy-nine percent (33/42) wei born to mothers with no known thyroid disorders. The mean confirmatory TSH was 140.4 mlU/L. Standard deviation was 24.5 mlU/L. The mean blood T4 was 18.5 pmol/L ( SD=5.3 pmol/L ). Kruskall-Wallis test (j value=0.0345) suggests a statistically significant difference in TSH levels among the different etiologies. On furthe analysis, estimates of the mean TSH of the athyreotic group (178.78; 95 percent CI 120.17-237.39) is significantly elevatei compared with the normal group (64.38; 95 percent CI 47.07-81.69); but not significantly different from the dysgenetii group (143.68; 95 percent CI 71.75-215.61). The differences in the mean T4 levels among the different CH etiology group: were not statistically significant (p-value=0.11). Further, the differences in the distribution of the infants according to developmental status among the different CH etiologies are also not statistically significant (p-value=0.528). There were also no statistically significant differences in the distribution of developmental status of infants according to maternal thyroid status during pregnancy (p-value=1.000).
CONCLUSON: The lack of statistically significant findings in the study is due to the small sample size. A prospective long-term study involving a greater number of infants and mothers is therefore recommended to better define the relationships between thyroid gland anatomy and function, maternal thyroid status and developmental outcome of newborns with congenital hypothyroidism.