HIV-related opportunistic infections

HIV-related opportunistic infection (OI) risk in people living with HIV (PLWH) increases as the CD4 count declines. Risk also increases in patients who are not virologically suppressed, regardless of the CD4 count.

For most PLWH with an acute OI, antiretroviral treatment (ART) should be considered within the first 2 weeks of initiation of treatment. However, in patients with tuberculosis (TB) it might be appropriate to wait for a therapeutic response before starting ART.

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 Mycobacterium avium complex), 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 PLWH.

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 OIs are infections that can occur as a result of impaired cell-mediated 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 respond to antiretroviral treatment. Tuberculosis, Pneumocystis jirovecii pneumonia, candidiasis, cryptococcosis, toxoplasmosis, cytomegalovirus, Mycobacterium avium complex, and coccidioidomycosis infections are among the HIV-related OIs often encountered in clinical practice and are covered in this topic.​[1]National Institutes of Health, Centers for Disease Control and Prevention, HIV Medicine Association, and Infectious Diseases Society of America. Panel on Guidelines for the Prevention and Treatment of Opportunistic Infections in Adults and Adolescents with HIV. Guidelines for the prevention and treatment of opportunistic infections in adults and adolescents with HIV: Mycobacterium tuberculosis. 2024 [internet publication]. https://clinicalinfo.hiv.gov/en/guidelines/hiv-clinical-guidelines-adult-and-adolescent-opportunistic-infections/whats-new