Congenital adrenal hyperplasia testing in the Malaysian population: real-world data sourced from a national reference laboratory.

Congenital Adrenal Hyperplasia (CAH) is primarily caused by mutations in genes responsible to produce enzymes involved in the synthesis of cortisol, aldosterone, or both. This study aims to determine the prevalence, sociodemographic distributions, and clinical factors associated with CAH in the Malaysian population. This retrospective study reviewed laboratory records of 17-hydroxyprogesterone (17OHP) test requests received at the Institute for Medical Research, Kuala Lumpur from January 2021 to December 2021. Descriptive statistics were employed for most variables, and logistic regression analysis was conducted to determine factors associated with CAH. The dataset included a total of 775 patients (64.2%) from 1,207 test requests screened. The prevalence of newly diagnosed CAH in the year 2021 was 13.5% (n=105). The majority were Malays (15.1%), neonates (13.8%), and females (45.7%). Higher baseline 17-OHP (cOR:1.31, 95% CI:1.19, 1.45), unknown gender at birth (cOR:7.82, 95% CI:2.86, 21.37), and neonatal age group at presentation (cOR:29.3, 95% CI:12.07, 71.03) independently predict CAH. The high prevalence of CAH in our region has been speculated to be due to the cultural consanguinity norms, resulting in genetic aberrations. CAH may manifest as ambiguous genitalia, particularly in females, due to the overproduction of androgens in-utero, resulting in atypical genitalia, necessitating thorough investigation. To the best of our knowledge, the data presented are the latest report on CAH prevalence, distribution, and description of positive CAH cases in the Malaysian population. These findings are essential for further public health planning to improve the diagnostic capacity and clinical management of CAH.