CONTEXT: In our neonatal program, a number of infants with congenital hypothyroidism (CH) had escaped diagnosis, when a spot RIA-TSH value of 20 mU/liter whole blood was used as a cutoff point. OBJECTIVE: The objective of the study was to find out prospectively the additional number of newborns with CH if the TSH cutoff point is lowered to 10 mU/liter. POPULATION AND METHODS: The study included 311,390 screened newborns. The children with CH were followed up for a period of 3 yr. RESULTS: Twenty-eight percent of infants diagnosed with CH had neonatal TSH values between 10 and 20 mU/liter (56 of 200). Forty of 47 infants, who were reevaluated later on (85.1%), suffered permanent CH. A thyroid scintiscan and/or echogram revealed that eight of 40 children (20.0%) had a structural defect, and the remaining (32 of 40) had a functional defect of the thyroid gland without anatomical abnormality; 14 of 32 cases were familial. Eighteen of the 47 reevaluated infants were prematurely born (38.3%) and 15 of these 18 had permanent CH (83.3%). The lowering of TSH cutoff point from 20 to 10 mU/liter resulted in a 10-fold increase of recall rate. CONCLUSIONS: A significant number of cases with permanent CH are missed when a TSH threshold of 20 mU/liter is applied. Almost 40% of the missed CH cases were premature. A mild increase of TSH at screening is not a predictor of transient CH. The increase in recall rate constitutes a serious drawback and should be balanced against the possible consequences of thyroid dysfunction at this important developmental stage.
CONTEXT: In our neonatal program, a number of infants with congenital hypothyroidism (CH) had escaped diagnosis, when a spot RIA-TSH value of 20 mU/liter whole blood was used as a cutoff point. OBJECTIVE: The objective of the study was to find out prospectively the additional number of newborns with CH if the TSH cutoff point is lowered to 10 mU/liter. POPULATION AND METHODS: The study included 311,390 screened newborns. The children with CH were followed up for a period of 3 yr. RESULTS: Twenty-eight percent of infants diagnosed with CH had neonatal TSH values between 10 and 20 mU/liter (56 of 200). Forty of 47 infants, who were reevaluated later on (85.1%), suffered permanent CH. A thyroid scintiscan and/or echogram revealed that eight of 40 children (20.0%) had a structural defect, and the remaining (32 of 40) had a functional defect of the thyroid gland without anatomical abnormality; 14 of 32 cases were familial. Eighteen of the 47 reevaluated infants were prematurely born (38.3%) and 15 of these 18 had permanent CH (83.3%). The lowering of TSH cutoff point from 20 to 10 mU/liter resulted in a 10-fold increase of recall rate. CONCLUSIONS: A significant number of cases with permanent CH are missed when a TSH threshold of 20 mU/liter is applied. Almost 40% of the missed CH cases were premature. A mild increase of TSH at screening is not a predictor of transient CH. The increase in recall rate constitutes a serious drawback and should be balanced against the possible consequences of thyroid dysfunction at this important developmental stage.
Authors: George A Ford; Sara Denniston; David Sesser; Michael R Skeels; Stephen H LaFranchi Journal: Horm Res Paediatr Date: 2016-09-06 Impact factor: 2.852
Authors: A Cassio; C Corbetta; I Antonozzi; F Calaciura; U Caruso; G Cesaretti; R Gastaldi; E Medda; F Mosca; E Pasquini; M C Salerno; V Stoppioni; M Tonacchera; G Weber; A Olivieri Journal: J Endocrinol Invest Date: 2013-02-12 Impact factor: 4.256