ESPE Abstracts

Screening for congenital adrenal hyperplasia through the measurement of 17-hydroxyprogesterone on the neonatal blood spot, aims to: prevent neonatal deaths; allow earlier identification and thereby decrease the severity of the initial salt-wasting episode; and to shorten the time during which a severely virilized genetic female newborn may be assigned the male sex. It is now practiced in most high-income countries, although the positive predictive value of the test is very low in premature infants, who seem to be infrequently affected. In almost all low- and middle-income countries, it has not yet been implemented.

Methods: To determine if it is justified in such a country, we evaluated the prevalence of premature birth and the sex ratio in a cohort of 299 singleton Algerian infants. We reviewed the medical records of all children with CAH referred to six teaching hospitals in Algiers, Algeria during a period of 20 years. The specific type of enzyme deficiency, 21-hydroxylase (21OHD), 11-beta-hydroxylase (11OHD) or 3-beta-ol dehydrogenase (3BHSD) was determined by serum steroid levels and confirmed by mutation analysis in some. Exclusion criteria were: gestational age (GA) not available, prenatal treatment with Dexamethasone until birth, and multiple pregnancy. Preterm births were classified by GA, in weeks, according to the WHO definitions, as late (34-37), moderate (32-34), very (28-32) and extreme (< 28). We also performed a literature search in PubMed, Scopus, Science direct and Google Search

Results: Congenital adrenal hyperplasia was confirmed in 93 boys and 139 girls with the salt-wasting form of the disease. Only 4% were born before 37 weeks of GA, less than the 14.3 % observed in the general Algerian population. None was born before 34 weeks of gestation. In 13 of 16 series of the literature reporting the GA age of CAH patients, the percentage of children with CAH born preterm is lower than that in the general population worldwide. More importantly, in three series totaling 358 patients, not a single one was born preterm

Conclusion: We speculate that the combination of a high production of 17-hydroxyprogesterone with a low production of cortisol by the fetus with congenital adrenal hyperplasia accounts for the rarity of very preterm birth in this population. We conclude that newborn screening for congenital adrenal hyperplasia is necessary in Algeria to equalize the sex ratio but that it could be restricted to neonates born after 32 weeks of gestation, thereby improving the cost-effectiveness ratio of this intervention.