Immune Reconstitution Inflammatory Syndrome (IRIS)

 

Features of IRIS:

(1) discontinuation of TNF alpha blocking therapy

(2) appearance of a systemic inflammatory response to a previously occult infection with massive Th1 response with release of interferon-gamma and TNF-alpha

 

Underlying infections may include:

(1) tuberculosis or other mycobacterial infection

(2) histoplasmosis or other deep fungal infection

 

The discontinuation of the TNF alpha blocking therapy results in better control of the underlying infection but the patient may be miserable with new onset of fever and systemic symptoms including organ failures.

 

Systemic administration of corticosteroids may improve the clinical symptoms.

 

Differential diagnosis:

(1) progressive disseminated infection