Which condition is primarily treated with adrenocortical agents?

Adrenocortical agents, which include corticosteroids, are primarily used in the management of conditions that involve excess cortisol production or where there is a need to suppress inflammation and the immune response. Cushing's disease is characterized by an overproduction of cortisol, often due to a pituitary adenoma. The treatment for Cushing's may involve the use of adrenocortical agents to help manage symptoms and complications associated with this excess hormone when surgical options are not viable or as a bridge to surgery.

In contrast, hypothyroidism is primarily managed with thyroid hormone replacement rather than adrenocortical agents. Diabetes mellitus primarily focuses on insulin or oral hypoglycemic agents for glucose control, and hypertension usually requires diuretics or antihypertensive medications, rather than the use of corticosteroids which might actually exacerbate hypertension due to fluid retention and increased blood pressure. Therefore, the correct choice emphasizes the specific role of adrenocortical agents in treating conditions characterized by adrenal dysfunction, particularly excess cortisol as seen in Cushing's disease.