Newborn screening for congenital adrenal hyperplasia has reduced sensitivity in girls.
OBJECTIVE
To characterize Wisconsin-born infants with 21-hydroxylase deficiency-congenital adrenal hyperplasia (21-OH-D-CAH) who were not identified by the newborn screening for 21-OH-D-CAH, and to examine male and female screening 17-hydroxyprogesterone (17-OHP) levels.


METHODS
Information on infants with false-negative results was gathered. Results of the Wisconsin newborn screening for 21-OH-D-CAH from January 1, 2000, to June 30, 2003, were analyzed to detect possible differences between male (n=119,842) and female (n=114,951) infants.


RESULTS
Six of 7 female infants with false-negative results had genital masculinization, and 4 of 8 infants with false-negative results had laboratory evidence of salt-wasting. None died, had a salt-wasting crisis, or was assigned the wrong sex. A significant difference in the mean 17-OHP levels between male (17.5 ng/mL) and female (15.4 ng/mL) infants (P <.0001) was detected. The sensitivity of newborn screening for female infants was 60%, compared with 80% for male infants.


CONCLUSIONS
Male and female infants have significantly different mean 17-OHP levels on newborn screening, and female infants comprise most of the infants with false-negative results. Although health professionals should not assume that newborn screening for 21-OH-D-CAH is a means of identifying all affected infants, the primary goals of newborn screening for CAH (prevention of salt-wasting crises and sex misassignment) are fulfilled.
Varness
Todd S
TS
Department of Pediatrics, University of Wisconsin Children's Hospital, Madison, Wisconsin 53792-4108, USA.
Allen
David B
DB
Hoffman
Gary L
GL
D019326:17-alpha-Hydroxyprogesterone / Q000097:blood*; D000312:Adrenal Hyperplasia, Congenital / Q000097:blood* / Q000150:complications / Q000175:diagnosis*; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D015997:Neonatal Screening; D011188:Potassium / Q000097:blood; D011237:Predictive Value of Tests; D012737:Sex Factors; D012964:Sodium / Q000097:blood; D014770:Virilism / Q000209:etiology; D014922:Wisconsin
D019326:17-alpha-Hydroxyprogesterone; D012964:Sodium; D011188:Potassium