INTRODUCTION
Congenital Adrenal Hyperplasia (CAH) is a group of inherited disorders
caused by genetic defects that hinder the production of adrenal
hormones, cortisol, and aldosterone, either completely or at their
normal rate. It may be caused by a deficiency of one of the five enzymes
responsible for cortisol synthesis. These enzymes include
21α-hydroxylase, 11β-hydroxylase and 17α-hydroxylase/17,20-lyase,
cholesterol 20,22 desmolase and 3β-hydroxysteroid dehydrogenase [1].
Adrenal steroidogenesis occurs by a series of steps facilitated by the
zone-specific enzyme expression and different types of CAH interrupt
this process at distinct branch points. Furthermore, there is a
substitute pathway for the endogenous synthesis of androgens, which also
plays a significant role in the causation of CAH [2,3]. CAH is
further categorized into two types - Classic & Non-Classic. Classic
CAH, although a more severe form, is rare and is usually detected at
birth and is associated with the life-threatening adrenal crisis in both
sexes and virilization of the external genitalia in 46, XX patients.
Non-Classic CAH is a more common form that has a milder phenotype in
which clinical problems are not obvious during the neonatal period or
childhood and generally develops during adolescence or adulthood
[4,5]. In Classic CAH, the findings usually visible at birth include
ambiguous genitalia in females due to excess male androgens, whereas in
males no overt abnormality of the external genitalia is present. In 95%
of the cases of CAH, the identified deficiency is of 21α-hydroxylase
enzyme [6]. This leads to impairment of cortisol and aldosterone
production with excess production of androgens that leads to the
aforementioned findings. We present a case of a four-month-old male
child who presented with Classic CAH with signs of dehydration,
malnutrition, and failure to thrive.