Addison disease

Right upper and middle lobar tree-in-bud densities with right upper lobar small nodular and patches of air space consolidation showing tiny internal cavitation, likely representing residual inflammatory (granulomatous) process.

Bilateral adrenal diffuse enlargement (larger and mass like-like on the left side) showing calcficationscalcifications.

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 “adrenalitis” 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 chronic:

• acute Addison disease occurs within a few weeks to months and is caused by bilateral adrenal haemorrhage (adrenal apoplexy), secondary to shock and sepsis or trauma. On CT scan bilateral adrenal haematomas are demonstrated. 
• subacute disease (adrenalitis): when the disease has been present for less than 2 years. On CT enlargement of both adrenal glands, with necrotic centres and a rim of contrast enhancement are usually demonstrated. A CT-guided biopsy helps to identify the cause such as tuberculosis, histoplasmosis, and other fungi. 
• chronic 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.