Which deficiency leads to congenital hypocortisolism?

Congenital hypocortisolism, often manifesting as adrenal insufficiency in infants, can arise from deficiencies in specific enzymes involved in steroid hormone biosynthesis. The adrenal cortex produces hormones such as cortisol, aldosterone, and adrenal androgens, and disruptions to the pathways that synthesize these hormones can lead to varying clinical presentations depending on which enzyme is deficient.

Among the enzymes listed, 21-hydroxylase deficiency is the most common cause of congenital adrenal hyperplasia (CAH) and directly leads to reduced production of cortisol and aldosterone, causing significant adrenal insufficiency. 11-hydroxylase deficiency can also result in reduced cortisol synthesis, but it leads to the accumulation of mineralocorticoid precursors, affecting fluid and electrolyte balance differently. Additionally, 17-hydroxylase deficiency leads to a lack of sex steroid and cortisol production, which also results in adrenal insufficiency.

The correct choice recognizes that any of the deficiencies in 11-hydroxylase, 17-hydroxylase, or 21-hydroxylase can lead to varying degrees of congenital hypocortisolism. Each of these enzyme deficiencies disrupts the pathway that ultimately produces cortisol, though they may also affect