Almost close, but it's A. because: Autoimmune adrenalitis is the most common cause of primary adrenal insufficiency in the United States. An autoimmune cause is also most likely in this patient because she has a history of Graves disease, an autoimmune-mediated thyroiditis. Patients with autoimmune diseases tend to have other simultaneous autoimmune-mediated conditions. Although skin hyperpigmentation is characteristic of Addison disease secondary to increased MSH, this patient presents with patches of depigmentation. This depigmentation is known as vitiligo and is also common in patients with autoimmune disease. The vitiligo occurs through an autoimmune-mediated attack on melanocytes. The diagnosis of Addison disease can be confirmed with laboratory findings of low morning cortisol levels (<3 μg/dL) and high plasma ACTH levels (≥100 pg/mL).
A. Autoimmune adrenalitis is the most common cause of primary adrenal insufficiency in the United States. An autoimmune cause is also most likely in this patient because she has a history of Graves disease, an autoimmune-mediated thyroiditis. Patients with autoimmune diseases tend to have other simultaneous autoimmune-mediated conditions. Although skin hyperpigmentation is characteristic of Addison disease secondary to increased MSH, this patient presents with patches of depigmentation. This depigmentation is known as vitiligo and is also common in patients with autoimmune disease. The vitiligo occurs through an autoimmune-mediated attack on melanocytes. The diagnosis of Addison disease can be confirmed with laboratory findings of low morning cortisol levels (<3 μg/dL) and high plasma ACTH levels (≥100 pg/mL).
