What Is Immune Reconstitution Inflammatory Syndrome?

Immune reconstitution inflammatory syndrome (IRIS) is a complication of HIV in which a patient's improving immune system causes mass inflammation in response to an already present opportunistic infection. IRIS occurs when an HIV patient with a compromised immune system starts to respond to antiretroviral medication. Symptoms arise rapidly and can be fatal if the infection involves the brain. Treatment for IRIS involves re-treating the underlying condition that caused the infection.

HIV affects the immune system, killing specialized white blood cells known as T-cells in order to replicate. With the body no longer able to fight off even simple infections such as colds, most HIV patients succumb to other infections rather than HIV. Medications known as antiretrovirals slow the process of HIV replications. These medications can have great success, holding the virus back and increasing T-cell levels to almost normal. It is when virus levels drop and T-cell levels rise that immune reconstitution inflammatory syndrome can occur.

Before a patient begins antiretroviral treatment, he or she may have already contracted a viral infection. As the body cannot produce an immune response, the patient may not experience symptoms. In other cases, the patient had a previously treated infection that continues to linger within the body. When the patient begins antiretroviral treatment, the improving immune system begins to attack the opportunistic infection.

Inflammation is the body's natural response to infection. The symptoms of immune reconstitution inflammatory syndrome are generally localized. Fever and pain, symptoms normal when a healthy person catches an infection, are greatly intensified when an HIV patient experiences IRIS. The condition is potentially fatal, especially if the inflammation is in the brain. More likely, though, is that a patient will experience some tissue damage where the inflammation takes place.

Treating immune reconstitution inflammatory syndrome requires treating the opportunistic infection. Antibiotics and other treatment involving a hospital stay may be required. A course of corticosteroids helps most patients in lessening their inflammation. Recovering from any illness is complicated when a patient has HIV; physicians more closely monitor a patient's recovery. An individualized treatment plan is always necessary.

If a patient recovers from immune reconstitution inflammatory syndrome, he or she can continue antiretroviral therapy. Prognosis is generally good if a patient continues his or her therapy, following all dosage instructions. Any illnesses a patient catches after recovery will produce normal symptoms and not an extreme inflammatory response. If IRIS causes tissue damage, extra medical treatment may be necessary.