Immune reconstitution syndrome

This code represents the paradoxical worsening of an existing infection or the unmasking of a previously subclinical infection, or the development of an autoimmune condition, following the initiation of highly active antiretroviral therapy (HAART) or other immunosuppressive treatment. It occurs as the immune system recovers and begins to mount an inflammatory response to antigens that were previously tolerated due to immunosuppression.

Assign this code when documentation clearly indicates a patient is experiencing symptoms consistent with immune reconstitution inflammatory syndrome (IRIS) after starting or restarting immunosuppressive therapy, most commonly HAART for HIV. Supporting documentation should specify the underlying infection or autoimmune condition that is flaring or emerging, and the temporal relationship to immune system recovery.

• Always code the underlying infection or autoimmune condition that is flaring or emerging due to immune reconstitution, in addition to this code.
• Do not confuse with opportunistic infections that occur due to continued immunosuppression; IRIS specifically relates to immune recovery.
• Ensure documentation specifies "immune reconstitution syndrome" or "IRIS" to support the use of this specific code.