Which condition is characterized by destruction of the adrenal gland?

Primary adrenal insufficiency, also known as Addison's disease, is characterized by the destruction of the adrenal glands, leading to insufficient production of adrenal hormones such as cortisol and aldosterone. This condition typically arises from autoimmune destruction of the adrenal cortex, although it can also result from infections, metastatic cancer, or other factors that damage the gland.

In primary adrenal insufficiency, the lack of cortisol can lead to a range of symptoms, including fatigue, weight loss, low blood pressure, and hyperpigmentation of the skin. Aldosterone deficiency can cause electrolyte imbalances, particularly hyponatremia and hyperkalemia.

On the other hand, secondary adrenal insufficiency involves an insufficient amount of adrenocorticotropic hormone (ACTH) from the pituitary gland, which leads to reduced stimulation of the adrenal glands but does not directly involve destruction of the adrenal glands themselves. Conditions like Cushing syndrome are characterized by excessive cortisol production, rather than destruction of the adrenal tissue, and pheochromocytoma relates to adrenal tumors and the overproduction of catecholamines, not the destruction of the gland. Thus, primary adrenal insufficiency is the correct choice as it directly reflects the condition of adrenal gland destruction.