The risk of OIs in HIV-infected people increases as the CD4+ count declines. Risk also increases in patients who are not receiving, or are not responding to, antiretroviral treatment (ART).
For most HIV-infected patients with an acute OI, ART should be considered within the first 2 weeks of initiation of treatment for the acute OI. However, in TB it might be appropriate to wait for a therapeutic response before ART is started.
The use of ART among patients treated for OIs is complicated by drug interactions, drug toxicity profiles, and immune reconstitution inflammatory syndrome (IRIS). IRIS has been observed most commonly with mycobacterial infections (TB and disseminated MAC), but may also develop with other OIs.
Primary and secondary prophylaxis against OIs is essential in the prevention of an initial or recurrent episode of OIs in HIV-infected patients.
Prophylaxis against many OIs can be discontinued for patients who respond to ART and maintain a CD4+ count above the recommended threshold for more than 3 months. However, if the CD4+ count decreases below that threshold, prophylaxis should be resumed.
HIV-related opportunistic infections (OIs) are clinical syndromes that arise as a consequence of impaired immunity in advanced stages of HIV infection. These illnesses tend to occur most often in patients who have untreated HIV infection or who fail to benefit from antiretroviral treatment. TB,
Pneumocystis jiroveci
pneumonia, candidiasis, cryptococcosis, toxoplasmosis, cytomegalovirus, and
Mycobacterium avium
complex infections, herpes simplex virus infection, and cryptosporidiosis are among the HIV-related OIs often encountered in clinical practice.
[1]
Centers for Disease Control and Prevention. 1993 revised classification system for HIV infection and expanded surveillance case definition for AIDS among adolescents and adults. MMWR Recomm Rep. 1992 Dec 18;41(RR-17):1-19.
http://www.cdc.gov/mmwr/preview/mmwrhtml/00018871.htm
http://www.ncbi.nlm.nih.gov/pubmed/1361652?tool=bestpractice.com