Difficulties in CAH Diagnosis Associated with Newborn Screening

 Excerpted from: "Difficulties in CAH Diagnosis Associated with Newborn Screening"
Bradford L. Therrell, Jr., and Sheri A. Berenbaum, New Horizons in Neonatal Screening, Elsevier Sueice B.V., J.P. Farriaux and J.L. Khondt, editors, 1994

Texas Newborn Screening Program has included Congenital Adrenal Hyperplasia (CAH) screening since June 1, 1989. CAH screening is aimed to identify and treat infants suffering from 21-hydroxylase deficient CAH. Classical CAH, existing in either salt-wasting (SW) or simple virilizing (SV) form, results in cortisol deficiency and requires corticosteroid replacement.

Newborns with SW-CAH may die if untreated. Females with SW- or SV-CAH have ambiguous genitalia. Males with SV-CAH have no clinical symptoms at birth but develop precocious puberty if left untreated.

Milder forms of non-saltwasting (NSW-CAH) exist with either no apparent clinical symptoms or late onset of symptoms. These non-classical forms of CAH are more difficult to identify since clinical signs of virilization do not exist or are minimal in newborns and biochemical abnormalities are subtle. Treatment protocols are not clearly established and therefore this group of patients presents difficulties in both disease confirmation and treatment following detection through newborn screening.

It has been relatively easy to diagnose the cases of SW-CAH because these infants have exhibited dehydration, virilization (in females), and high 17-OHP levels. On the other hand, differentiation of SV-CAH, especially in boys, has been difficult.

Studies have been undertaken to determined the cost effectiveness of CAH screening and the history of NC-CAH and the factors that affect physical and behavioral development of all CAH children. A reporting questionnaire was developed to include questions related to physical symptoms, laboratory results, and medical data for completion by the patient's endocrinologist. The combined studies underway will provide not only a better understanding of CAH as an endocrine disorder, but also a clearer understanding of the relationship between behavior and excess androgen exposure.

Last updated November 22, 2010