Resetting the Detection Level of Cord Blood Thyroid Stimulating Hormone (TSH) for the Diagnosis of Congenital Hypothyroidism

Abstract

An appraisal of a 17-year primary thyroid stimulating hormone (TSH) screening programme for the detection of congenital hypothyroidism was carried out to establish the reference interval of cord blood TSH in unaffected infants; the mean cord blood TSH concentration of affected infants and the incidence of congenital hypothyroidism in the Najran province of Saudi Arabia. Our findings show a reference interval of cord blood TSH of 2.0-16.8 mU/l in unaffected infants; a mean cord blood TSH concentration of 399 mU/l in affected infants; a false positive rate for the diagnosis of at-risk infants of 1.02% and a congenital hypothyroidism incidence rate of 34/100 000 (1 : 2931) live births. These findings suggest that there is a need to reset the cord blood TSH concentration for the detection of at-risk infants. We suggest that the detection level of cord blood TSH for the recognition of at-risk infants can be set at 90 mU/l rather than the recommended level of 30 mU/l. This should reduce the false positive rate for detection of infants at risk of congenital hypothyroidism.

Marked Biological Variance in Endocrine and Biochemical Markers in Childhood: Establishment of Pediatric Reference Intervals Using Healthy Community Children from the CALIPER Cohort

“…Therefore, relevant RIs are essential for correct test result interpretation and reducing the risk of false negatives and false positives. Failure to provide proper RIs in the pediatric population carries obvious consequences for immunochemical analytes such as TSH (8 ) and ferritin (9 ).…”

Closing the Gaps in Pediatric Laboratory Reference Intervals: A CALIPER Database of 40 Biochemical Markers in a Healthy and Multiethnic Population of Children

“…One study found that the use of inadequate serum ferritin reference intervals led to a substantial (Ͼ15%) underestimation of iron deficiency in low-income children (4 ). The lack of ageadjusted cutoffs for thyroid-stimulating hormone during neonatal screening for congenital hypothyroidism led to an increase in the frequency of false positives and to excessive follow-up rates (5,6 ). Mir et al (7 ) analyzed N-terminal B-type natriuretic peptide and observed age-specific sex differences, with children having concentrations up to 260% higher than those of adults.…”

Neonatal Screening for Congenital Hypothyroidism: A Retrospective Hospital Based Study from Bahrain

“…The average TSH cord blood levels in females and males were 10 was determined to be 1 :2,967 and 1:722 live births, respectively. The average TSH cord blood levels in females and males were 10 was determined to be 1 :2,967 and 1:722 live births, respectively.…”