What defines a patient with 11-hydroxylase deficiency?

In 11-hydroxylase deficiency, which is a form of congenital adrenal hyperplasia, the lack of the enzyme 11-hydroxylase leads to an accumulation of steroid precursors, particularly 11-deoxycorticosterone and 11-deoxycortisol. One of the key clinical features of this condition is the increased production of mineralocorticoids, particularly due to the buildup of precursors that are shunted toward the mineralocorticoid pathway. This results in hypertension and signs of excess mineralocorticoid activity despite impaired cortisol production.

Additionally, cortisol levels are typically low in this deficiency, which can contribute to the adrenal crisis and other metabolic disturbances. Unlike other forms of congenital adrenal hyperplasia, such as 21-hydroxylase deficiency, where significant androgen overproduction is common and leads to virilization, 11-hydroxylase deficiency is characterized by an increased mineralocorticoid surge without corresponding elevations in androgens to the same extent.

This understanding highlights the unique biochemical pathway disruption present in 11-hydroxylase deficiency and clarifies why increased mineralocorticoid production is the defining characteristic of this specific adrenal enzyme disorder.