J Lab Med Qual Assur.  2009 Dec;31(2):269-274.

Cutoff Value of 17-Hydroxyprogesterone Screening Test for Congenital Adrenal Hyperplasia According to Birth Weight

• Choi TY
• Kang JG
• Lee DH
• Song WH

Abstract

BACKGROUND
False positive rate of 17-OHP screening test was higher more than other screening tests due to use same cutoff value both term and preterm infants in Korea. The purpose of this study is to set cutoff value of 17-OHP on the basis of birth weight in neonatal screening for congenital adrenal hyperplasia.
METHODS
17-OHP was measured in filter paper blood spots obtained by heel puncture between 3 and 7 days after birth. 17-OHP values were analyzed with respect to birth weight in order to decide the appropriate cutoff values in a neonatal screening for congenital adrenal hyperplasia.
RESULTS
The mean concentrations of 17-OHP according to birth weight groups were as follows : 12.6, 7.0, 5.1, 3.7, 3.0, 2.5 ng/mL for birth weight of 1.50 or less, 1.50-1.99, 2.00-2.49, 2.50-2.99, 3.00-3.49, 3.50 kg or more, respectively. The cutoff values for determining the 17-OHP for recall were decided as follows : 55, 35, 18, 11, 8, 8 ng/mL for birth weight of 1.50 or less, 1.50-1.99, 2.00-2.49, 2.50-2.99, 3.00-3.49, 3.50 kg or more, respectively. Application of the new cutoff values according to birth weight dropped the total recall rate from 3.3% to 1.0%.
CONCLUSIONS
The cutoff values of 17-OHP on the basis of birth weight should be used in the neonatal screening for congenital adrenal hyperplasia. We believe that the recall rate due to false positive can be reduced using this method in low birth weight infants.

Keyword

17-Hydroxyprogesterone; Congenital adrenal hyperplasia; Neonatal screening; Birth weight

MeSH Terms

17-alpha-Hydroxyprogesterone
Adrenal Hyperplasia, Congenital
Birth Weight
Heel
Humans
Infant
Infant, Low Birth Weight
Infant, Newborn
Infant, Premature
Korea
Mass Screening
Neonatal Screening
Parturition
Punctures
17-alpha-Hydroxyprogesterone