The CDC recommends that every individual between the ages of 13 and 64 be tested for HIV at least once, and that persons at high risk for HIV infection be screened at least annually. The American College of Physicians encourages testing of all persons. The US Preventive Services Task Force recommends screening for adolescents and adults at increased risk for HIV infection, and for all pregnant women.
Risk factors for exposure to HIV include unprotected sexual intercourse, large number of sexual partners, history of sexually transmitted infection, blood transfusion, needle-stick injury, sharing of intravenous drug paraphernalia, mucosal contact with infected blood, and mother-to-child vertical transmission.
An ELISA test is used for screening. A positive immunoassay should be followed by confirmatory Western blot testing. A rapid detection combination antigen/antibody test is available. The CD4+ lymphocyte count is used for classification and to monitor for opportunistic infection. The viral load in peripheral blood is used to guide therapy; the rate of progression to AIDS and death is related to viral load.
The workup of a patient with newly diagnosed HIV infection should include an ophthalmologic examination and testing for TB, CMV, syphilis, hepatitis A–C, Toxoplasma, chlamydia, and gonococcus.
Centers for Disease Control and Prevention (CDC). Detection of acute HIV infection in two evaluations of a new HIV diagnostic testing algorithm—United States, 2011–2013. MMWR Morb Mortal Wkly Rep. 2013;62(24):489–494.
Joyce MP, Kuhar D, Brooks JT. Notes from the field: occupationally acquired HIV infection among health care workers—United States, 1985–2013. MMWR Morb Mortal Wkly Rep. 2015;63(53):1245–1246.
Excerpted from BCSC 2020-2021 series: Section 1 - Update on General Medicine. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.