Related Experiment Videos
Neonatal screening program for congenital adrenal hyperplasia: adjustments to the recall protocol
L Gruñeiro-Papendieck1, L Prieto, A Chiesa
1Fundación de Endocrinología Infantil, Centro de Investigaciones Endocrinológicas CEDIE, División de Endocrinología Hospital de Niños R. Gutiérrez, Capital Federal, Argentina. protir@cedie.guti.gov.ar
Insights
Gestational age and birth weight influence 17 alpha-OH-progesterone levels in neonatal screening for congenital adrenal hyperplasia. Adjusting screening cutoffs for these factors reduces false positives in preterm infants.
Area of Science:
- Neonatal screening
- Endocrinology
- Pediatric diagnostics
Background:
- Congenital adrenal hyperplasia (CAH) screening relies on 17 alpha-OH-progesterone (17-OHP) levels.
- Neonatal screening programs face challenges with high recall rates, particularly in preterm infants.
- Gestational age (GA) and birth weight (BW) are known factors influencing neonatal physiology.
Purpose of the Study:
- To assess the impact of GA and BW on 17-OHP levels.
- To determine how GA and BW affect the recall rate in CAH neonatal screening.
- To optimize screening protocols for congenital adrenal hyperplasia.
Main Methods:
- A pilot CAH screening program utilized fluoroimmunoassay for 17-OHP on dried blood spots.
- Analyzed 17-OHP levels in 1,313 preterm (23-36 weeks) and 1,500 term (>37 weeks) infants.
- Collected serial samples from preterm infants in their second week of life.
Main Results:
- Five cases of CAH were identified.
- The 30-nmol/l 17-OHP cutoff represented the 99th percentile in term newborns.
- Preterm infants exhibited higher 17-OHP levels, with inverse correlation to GA and BW.
Conclusions:
- GA and BW are crucial for adjusting 17-OHP cutoff levels in CAH screening.
- Adjusted criteria significantly reduce follow-up testing and parental anxiety.
- Implementing GA and BW adjustments can substantially lower false-positive recall rates in preterm infants.
Objective:
To evaluate the influence of gestational age (GA) and birth weight (BW) on 17 alpha-OH-progesterone (17-OHP) levels with respect to their impact on the recall rate of neonatal screening programs for congenital adrenal hyperplasia (CAH).
Patients And Methods:
In June 1997 we began a pilot screening program for CAH measuring 17-OHP using a fluoroimmunoassay method (DELFIA) on dried blood spots. Until September 1999, 24,153 babies were screened. Among them, we analyzed the levels of 17-OHP in 1,313 samples from healthy preterm babies (23-36 weeks) and 1,500 term babies (>37 weeks), grouped according to GA and BW. All preterm babies underwent another sampling in their 2nd week of life.
Results:
5 CAHs were detected. The 30-nmol/l cutoff limit for 17-OHP in blood corresponded to the calculated 99th percentile in term newborns, while in preterm babies higher levels were found. GA and BW correlated inversely with 17-OHP levels.
Conclusion:
GA and BW were useful tools to adjust cutoff levels, obtaining a significant reduction in follow-up testing and psychological stress for families. The high false-positive recall rate in preterm babies can be substantially lowered with adjusted GA and/or BW criteria.