Reference Values for Serum 17 α-Hydroxyprogesterone Levels in Neonates and Infants

TARIFA, C.; OCHETTI, M.; CABRAL, M.; AGUIRRE, M.; SOBRERO, G.; CABRERA, N.; COLLET, I.; SILVANO, L.; TESTA, G.; INCHAUSPE, M.; DE ELIAS, R.; KIENER, O.; ANDRADA, M.; MARTIN, S.; MIRAS, M.; MUÑOZ, L.

Puerto Varas

Encuentro; XXV Annual Meeting of the Latin American Pediatric Endocrinology Society (SLEP); 2015

Sociedad Latinoamericana de Endocrinología Pediátrica (SLEP)

Introduction: The measurement of 17α-hydroxyprogesterone (17OHP) is used for the diagnosis and monitoring of Congenital Adrenal Hyperplasia (CAH). Our previous date support the convenience of employing extractive procedures in the determination of 17OHP during the neonatal period and the first year of life toavoid the interferences observed during this stage. Since the degree of interference may vary between available assays, reference values for 17OHP should be method specific. Our aim is to analyze serum levels of direct 17OHP (17OHPd) and with previous extraction (17OHPe) by RIA-Inmunotech in healthy neonates and infants in order to establish reference values with regard to gestational age (GA), chronological age (CA), sex and birth weight (BW).Subjects and Methods: We analyzed 623 healthy newborns and infants (F:316/M:307), GA ≥37 weeks, BW ≥2500 g, CA: 1 to 365 days. The previous extractive procedure was performed with isopropanol/heptane 3%.Results: The analysis of 17OHPd and 17OHPe levels in healthy newborns showed significant correlation with CA (p < 0.001). To establish the reference values for 17OHPd and 17OHPe, percentiles of the frequency distribution P 98% were calculated (table 1). Conclusion: Our data confirm the convenience of employingextraction procedures and requires adequate specificity and accuracy in the determination of 17OHP. The references values here obtained by the current commercially available method ensures its usefulness in the diagnosis and control of the evolution of CAH patients.