Clinical features of primary vs central (secondary, tertiary) adrenal insufficiency
| Feature | Primary | Central | Possible explanation for difference |
|---|---|---|---|
| Skin hyperpigmentation | Yes | No | Adrenocorticotropic hormone production and thus melanocyte-stimulating hormone levels are increased in primary but not central adrenal insufficiency |
| Gastrointestinal symptoms | More prominent | Less prominent | More prominent electrolyte disturbances in primary adrenal insufficiency may play a role in gastrointestinal symptoms |
| Intravascular volume depletion, hypotension | More prominent | Less prominenta | Decreased serum aldosterone levels only in primary adrenal insufficiency |
| Hyperkalemia | Yes | No | Decreased serum aldosterone levels only in primary adrenal insufficiency |
| Hypoglycemia | Less prominent | More prominent | Concomitant growth hormone deficiency present in some cases of central adrenal insufficiency More insidious progression in central adrenal insufficiency resulting in delayed presentation and more prominent corticosteroid deficiency symptoms such as hypoglycemia |
| Blood urea nitrogen elevation | More frequent | Less frequent | Intravascular volume depletion resulting in prerenal azotemia is present more frequently in primary adrenal insufficiency |
| Hypopituitarism, headaches, visual field defects | No | Yes | Depends on the underlying cause |
↵a Secondary adrenal insufficiency such as pituitary apoplexy may present with hypotension and, if not treated, may lead to azotemia. However, this may occur much more frequently in patients with primary adrenal insufficiency.