Thyroid function in cord blood.
OBJECTIVE
To determine the biochemical parameters of thyroid function in the cord blood of Saudi infants.


METHODS
Cord blood samples sent to the Pathology Department for screening for congenital hypothyroidism were used to determine the reference ranges for thyrotropin, free thyroxine, free triiodothyronine, thyroxine-binding globulin and thyroglobulin. All the measurements were carried out by immunoassay (Elisa, microparticle enzyme immunoassay or chemiluminescence immunoassay). Reference ranges were calculated after exclusion of outliers.


RESULTS
Reference ranges for thyrotropin, free thyroxine and thyroxine-binding globulin were similar to published values, whereas those for free triiodothyronine and thyroglobulin were different.


CONCLUSIONS
For correct interpretation of the parameters of thyroid function in cord blood it is essential to have reference ranges based on the laboratory's current methods and derived from the local population.
Henry
G
G
Department of Pathology, Riyadh Armed Forces Hospital, PO Box 7897, Riyadh 11159, Kingdom of Saudi Arabia.
Sobki
S H
SH
Al-Beshara
N M
NM
Harkonen
M E
ME
Miller
H R
HR
D003409:Congenital Hypothyroidism; D005312:Fetal Blood / Q000737:chemistry*; D006801:Humans; D007037:Hypothyroidism / Q000097:blood* / Q000175:diagnosis / Q000453:epidemiology; D007118:Immunoassay; D007231:Infant, Newborn; D008163:Luminescent Measurements; D015997:Neonatal Screening; D012016:Reference Values; D012529:Saudi Arabia / Q000453:epidemiology; D013954:Thyroglobulin / Q000097:blood*; D013960:Thyroid Function Tests / Q000379:methods; D013963:Thyroid Hormones / Q000097:blood*; D013972:Thyrotropin / Q000097:blood*; D013974:Thyroxine / Q000097:blood*; D013975:Thyroxine-Binding Proteins / Q000378:metabolism*; D014284:Triiodothyronine / Q000097:blood*
D013963:Thyroid Hormones; D013975:Thyroxine-Binding Proteins; D014284:Triiodothyronine; D013972:Thyrotropin; D013954:Thyroglobulin; D013974:Thyroxine