A Pilot Newborn Screening for Congenital Adrenal Hyperplasia in Alaska*

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Abstract
A pilot newborn screening program for 21-hydroxylase deficiency congenital adrenal hyperplasia (CAH) was conducted in Alaska using a 3-mm disc filter paper elution technique of capillary whole blood for 17-hydroxyprogesterone (17-OHP) by RIA. The filter paper specimens were provided via the mandated newborn screening program. The highest values of 17-OHP in a control population of 4569 consecutive normal neonates, aged 2–14 days, was 40 pg/disc, and the range of values for 20 newborns with proven CAH was 57–980 pg/disc. All Alaskan newborns with 17-OHP levels of 57 pg/disc or greater were referred for diagnostic workup, and initially, those with 17-OHP levels of 41–56 pg/disc were recalled for a second specimen. However, the range for recall was changed subsequently to the 17-OHP level greater than 51 pg/disc, since no newborns with 17-OHP level below 50 pg/disc were found to be affected in the initial screening. In a 30-month period, the Alaskan newborns screened on the third day of life consisted of a total of 19,677 consecutive births (13,733 Caucasians, 1,131 Yupik Eskimos, 3,173 other natives, and 1,640 others). Sixteen had 17-OHP values greater than 57 pg/disc, of which 4 (3 Yupik Eskimos and 1 Caucasian) were proven to have the salt-losing form of CAH. Of the remaining 12, 4 were not available for follow-up; 8 were distressed premature infants, including 2 infants who died with severe prematurity. In addition, 1 Yupik Eskimo newborn who was clinically suspected and treated for CAH at birth before confirmation of the diagnosis, was subsequently confirmed to have CAH by filter paper 17-OHP determination off treatment. Of the 14 newborns whose 17-OHP values were 51–56 pg/disc, 13 were recalled and proven to be normal, and 1 could not be located. Thus, the neonatal Alaskan screening, including 1 newborn who was clinically suspected for CAH, revealed 4 infants with the salt-losing form of CAH in 1,131 live births in Yupik Eskimos and 1 infant with the salt-losing form of CAH in 13,733 Caucasian live births. These data indicate a prevalence of this disorder of 1 in 282 in Yupik Eskimo live births and 1 in 13,733 in Caucasian live births. The false positive and recall rates were 0.05% and 0.1%, respectively. The present study demonstrates the feasibility of a newborn screening program for CAH and indicates that the frequency of the salt-losing form of CAH may be greater than previously reported by the case assessment method in Yupik Eskimos in Alaska.