Addison disease

Granulomatous Infection (Tuberculosis) is the most common infectious cause of Addison disease. CT appearance of granulomatous infection depends on the time and activity of the inflammatory process. 

• early stage-stage “adrenalitis” include includes bilateral adrenal enlargement with a central necrotic area of hypoattenuation and a peripheral enhancing rim.
• In the healing stage of the disease, the adrenal glands become calcified and atrophic (adrenal calcification).

Addison disease may be either acute, subacute,or, or chronic.:

• Acuteacute Addison disease occurs within a few weeks to months and is caused by bilateral adrenal hemorrhage (adrenal apoplexy), secondary to shock and sepsis or trauma. On CT scan bilateral adrenal hematomas are demonstrated. 
• Subacutesubacute disease (adrenalitis): when the disease has been present for less than 2 years. On CT enlargement of both adrenal glands, with necrotic centers and a rim of contrast enhancement are usually demonstrated. A CT-guided biopsy helps to identifiyidentify the cause such as tuberculosis, histoplasmosis, and other fungi. 
• Chronicchronic disease: may be caused by a chronic autoimmune disorder, chronic granulomatous infection (TB or histoplasmosis). On CT both adrenal glands appear small and atrophic with associated with calcifications in granulomatous adrenalitis.