What is immune reconstitution syndrome?

Answer 1

Immune reconstitution syndrome (IRS), or immune reconstitution inflammatory syndrome (IRIS), is the name given to a diverse group of symptoms that can occur soon after a patient starts treatment with anti-HIV drugs (or as a patient recovers from any other serious immunosuppressing condition).

Although the condition is not yet fully understood, the paradox of the syndrome is that the patient appears to get ill because their immune system is reconstituting (getting healthier).

What seems to happen is that, as untreated HIV infection progresses, the immune system fails to mount as effective a response as it normally would to a whole range of opportunistic infections .. however, when drug therapy to combat the HIV infection is commenced - and the immune system grows stronger - there is a sudden upsurge in the response to these other opportunistic infections.

It is essentially a hypersensitivity reaction and will normally occur between three and twenty-four weeks after initiation of antiretroviral therapy.

The syndrome is particularly common when suppression of HIV is very rapid, or when therapy is commenced when the immune system is already dangerously compromised (i.e. at very low CD4 counts).

Studies seem to indicate that as many as 20% of patients starting anti-HIV treatment for the first time will experience some form of IRIS event and that this will occur at a median of 12 weeks after initiation of treatment.

In approximately 80% of cases IRIS manifested itself as an occurrence / reoccurrence of dermatological problems, which can vary from mild skin complaints to such things as warts, genital herpes, genital warts, molluscum contagiosum and chickenpox / shingles.

A much smaller number of patients experienced non-dermatological IRIS, with reoccurrence of tuberculosis symptoms and hepatitis B. There were also isolated instances of patients experiencing PCP and Kaposi's sarcoma relapses.

Although it is vital that you seek medical advice if you suspect that you are experiencing some sort of immune reconstitution syndrome (this is to guard against the very rare occurrence where it develops into something more serious); it is also important to note that these symptoms are generally a good sign and indicate that your immune system is growing healthier and is now able to deal with infections that it couldn't previously respond effectively to.

Personal experienceWhen I started antiretroviral therapy, I achieved full target suppression of HIV within ten days of starting treatment (which is about as quick a response as you can get).

IRS, although extremely mild, manifested itself in two waves:

• At around four weeks I developed a very mild flushing and redness on the central face and across the cheeks and nose.
• At around sixteen weeks, a small outbreak of warts on my face.

By week twenty-four, all of these had resolved themselves without any sort of medical intervention (except for freezing of the warts for cosmetic reasons).