title: Neonatal screening for congenital hypothyroidism using the filter paper thyroxine technique.
abstract: A total of 25,244 full term consecutive newborns were screened for hypothyroidism at 24 to 96 h of birth using the filter paper technique for thyroxine. The screening protocol based on our pilot study considered filter paper thyroxine (FP-T4) values of 51 to 80 ng/ml (-1 SD) as borderline and < 50 ng/ml (-2 SD) as high risk for congenital hypothyroidism. FP-T4 and/or serum T4 and TSH were reestimated in all neonates with FP-T4 < 80 ng/ml. A total of 4775 (18.9%) newborns (FP-T4, 51 to 80 ng/ml in 4435 and < 50 ng/ml in 340) needed the recall; 2237 (50.4%) with FP-T4 51 to 80 ng/ml recalled by letters and 283 (83.3%) of the 340 subjects with FP-T4 < 50 ng/ml recalled by home visit, responded by 6 wk of age. Congenital hypothyroidism was confirmed in 6 newborns. FP-T4 in one persisted at 55 ng/ml on follow up and in the remainder both initial and repeat values were < 50 ng/ml. Follow up serum T4 values were subnormal (7.8-50.2 ng/ml) and serum TSH elevated (80-1233 IU/ml). Technetium thyroid scan showed agenesis in 3, ectopia in 2 and normal gland with probable dyshormonogenesis in one. Three other newborns (FP-T4 93 to 143 ng/ml) escaped primary detection and were referred later for congenital hypothyroidism. The incidence of congenital hypothyroidism by primary screening was 1:4207 (6 of 25,244) but with these 3 missed cases, probably 1:2804. Congenital hypothyroidism was reconfirmed in all 9 infants between the ages of 2 1/2 to 4 yr.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Bai Jerbai Wadia Hospital for Children, Bombay.
authors.forename: M P
authors.initials: MP
authors.lastname: Desai
authors.forename: P
authors.initials: P
authors.lastname: Upadhye
authors.forename: M P
authors.initials: MP
authors.lastname: Colaco
authors.forename: M
authors.initials: M
authors.lastname: Mehre
authors.forename: S P
authors.initials: SP
authors.lastname: Naik
authors.forename: F E
authors.initials: FE
authors.lastname: Vaz
authors.forename: N
authors.initials: N
authors.lastname: Nair
authors.forename: M
authors.initials: M
authors.lastname: Thomas
mesh_terms: D003409:Congenital Hypothyroidism; D005500:Follow-Up Studies; D006801:Humans; D007037:Hypothyroidism / Q000175:diagnosis*; D007231:Infant, Newborn; D015997:Neonatal Screening / Q000379:methods*; D010865:Pilot Projects; D013974:Thyroxine / Q000097:blood*
chemical_list: D013974:Thyroxine