Which is a primary cause of adrenal insufficiency?

Which is a primary cause of adrenal insufficiency?

• A. Tuberculosis
• B. Hemorrhage
• C. Autoimmune Disorders
• D. Secondary Adrenal Insufficiency Due to Pituitary Failure

Answer: (C)

Distinguishing the most common cause of primary adrenal insufficiency is about recognizing that the problem lies in the adrenal glands themselves, not in the pituitary. When the adrenal cortex is destroyed, cortisol and often aldosterone decline, leading to the characteristic Addisonian picture. Autoimmune destruction of the adrenal cortex is the most frequent cause of this primary form in many settings. In autoimmune adrenalitis, the immune system targets adrenal enzymes (such as 21-hydroxylase), triggering progressive lymphocytic infiltration and loss of functional cortex. This direct attack on the adrenal glands explains why cortisol and aldosterone drop, producing fatigue, weight loss, low blood pressure, hyponatremia, hyperkalemia, and often hyperpigmentation from excess ACTH. Tuberculosis can involve the adrenal glands and cause primary insufficiency by granulomatous destruction, but it is less common in many modern contexts compared to autoimmune causes. Adrenal hemorrhage can cause acute primary insufficiency, but it is not the typical chronic, most common cause. Secondary adrenal insufficiency due to pituitary failure is not primary—it's a problem of the pituitary, leading to low ACTH with relatively preserved aldosterone and a different clinical and laboratory profile. So autoimmune adrenalitis stands out as the leading cause of primary adrenal insufficiency because it directly damages the adrenal cortex, producing the full spectrum of hormonally driven deficits seen in Addison’s disease.

Distinguishing the most common cause of primary adrenal insufficiency is about recognizing that the problem lies in the adrenal glands themselves, not in the pituitary. When the adrenal cortex is destroyed, cortisol and often aldosterone decline, leading to the characteristic Addisonian picture.

Autoimmune destruction of the adrenal cortex is the most frequent cause of this primary form in many settings. In autoimmune adrenalitis, the immune system targets adrenal enzymes (such as 21-hydroxylase), triggering progressive lymphocytic infiltration and loss of functional cortex. This direct attack on the adrenal glands explains why cortisol and aldosterone drop, producing fatigue, weight loss, low blood pressure, hyponatremia, hyperkalemia, and often hyperpigmentation from excess ACTH.

Tuberculosis can involve the adrenal glands and cause primary insufficiency by granulomatous destruction, but it is less common in many modern contexts compared to autoimmune causes. Adrenal hemorrhage can cause acute primary insufficiency, but it is not the typical chronic, most common cause. Secondary adrenal insufficiency due to pituitary failure is not primary—it's a problem of the pituitary, leading to low ACTH with relatively preserved aldosterone and a different clinical and laboratory profile.

So autoimmune adrenalitis stands out as the leading cause of primary adrenal insufficiency because it directly damages the adrenal cortex, producing the full spectrum of hormonally driven deficits seen in Addison’s disease.