NBME 24 Answers ↦
The combination of low blood pressure (from lack of mineralocorticoids) and low glucocorticoids (cortisol) indicate adrenal failure. Hyperpigmented skin is a sign of elevated ACTH, indicating that this is a failure of the adrenal gland and not the pituitary. In the industrialized western world, autoimmune destruction of adrenal glands is the leading cause of primary adrenal failure (disseminated tuberculoid destruction of the adrenal glands is significant outside of industrialized nations).
It also fits the time line better than Waterhouse-Friederichsen syndrome, which is sudden in onset and associated with hemorraging. Metastases to the adrenal glands *might* be a possibility, but autoimmune destruction is simply likelier.
Chronic Addisons disease.
Pretty straightforward here. Decreased gland function -> decreased Cortisol, decreased Aldosterone -> hypotension (with hyponatremic volume contraction)
Hyperpigmentation from increased ACTH (from POMC) making MSH.
(FA) Due to adrenal atrophy or destruction by disease (autoimmune destruction most common in the Western world; TB most common in the developing world).
I picked autoimmune adrenalitis but was tempted to pick Waterhouse syndrome because of the low BP (hemorrhaging). But I believe Waterhouse-Fried. syndrome is more likely associated with Neisseria infection