Causes of Adrenal Insufficiency
| Primary adrenal insufficiency | |
|---|---|
| Cause | Examples |
| Infective | Tuberculosis |
| Infiltrative | Metastatic disease Amyloid Haemochromatosis |
| Vascular (bilateral adrenal haemorrhage) | Antiphospholipid syndrome Sepsis (Waterhouse-Friderichsen syndrome):
|
| Congenital | Congenital adrenal hyperplasia |
| Congenital adrenal hypoplasia | |
| Adrenoleukodystrophy | |
| Autoimmune* | Isolated autoimmune adrenalitis |
| Autoimmune polyglandular syndromes | |
| Iatrogenic | Bilateral adrenalectomy (for Cushing's disease, oncological resection) Drug-induced:
|
| Secondary adrenal insufficiency‡ | |
|---|---|
| Cause | Examples |
| Infective | Tuberculosis |
| Infiltrative | Neurosarcoidosis Haemochromatosis Langerhans cell histiocytosis |
| Inflammatory/autoimmune | hypophysitis (lymphocytic, IgG4, immune checkpoint inhibitors, other) Isolated corticotroph autoimmunity Autoimmune polyglandular syndromes |
| Vascular | Sheehan's syndrome Pituitary apoplexy |
| Congenital | Various rare genetic or developmental defects |
| Neoplastic | Pituitary adenoma Metastasis Craniopharyngioma Pituitary carcinoma Meningioma Invasion of other intracranial tumour |
| Iatrogenic | Exogenous glucocorticoids Hypophysectomy Pituitary radiotherapy Radiation of other head and neck tumour |
| Unknown | ‘Empty sella syndrome’ |
* 90% of primary adrenal insufficiency is due to autoimmune adrenalitis.
‡ Secondary adrenal insufficiency is roughly twice as prevalent as primary. Exogenous glucocorticoid commonly causes transient adrenal insufficiency. The commonest cause of permanent secondary adrenal insufficiency is a pituitary tumour and consequent treatment, with sufficient damage to pituitary function to result in hypopituitarism.