CAH Flashcards
DDx hirsutism
85% polycystic ovarian syndrome
10% idiopathic
3% congenital adrenal hyperplasia
others: neoplasm, Cushing’s, exogenous androgens use
acanthosis nigricans
connotes insulin resistance
most common cause of CAH
21-hydroxylase deficiency
draw adrenal hormone schematic
see notes
why is the 21-hydroxylase gene so frequently mutated?
nearby pseudogene w/ lots of homology that easily picks up mutations (not normally expressed)
+ freq crossover b/t this gene and the real gene
classic form of 21-hydroxylase deficiency
no 21-OHase activity
presents as newborn
genitalia: female= ambiguous, male= precocious
cortisol and aldosterone deficiency
growth: short (early growth –> epiphyseal plates close early)
nonclassical form of 21-hydroxylase deficiency
presents in adolescence
genitalia, cortisol, aldosterone normal
20-50% 21-OHase deficiency
how to dx 21-hydroxylase deficiency
measure 17-OH-progesterone b/f and after ACTH injection
tx goals in 21 hydroxylase deficiency
reverse adrenal insufficiency
suppress androgen excess
female: in utero - prevent genital ambiguity; in adult - prevent hirsutism, fertility, pscyh
male: child - behavior probs, short stature
tx for 21-hydroxylase deficiency
give exogenous cortisol to restore cortisol and reduce ACTH secretion –> less androgen excess and adrenal secretion
CAH phenotype is determined by…
most functional allele
17-alpha hydroxylase deficiency
increased mineralocorticoids, lack cortisol and sex hormones
labs: hypertension, hypokalemia
11-beta hydroxylase deficiency
mineralocorticoids: decreased aldosterone, increased 11-deoxycortisol (increases BP) decreased cortisol increased androgens labs: hypertension presentation: XX virilization
