Should HIV-Infected Patients in the U.S. Routinely Be Screened for Cryptococcal Infection?

Carlos del Rio, MD

Among patients with advanced HIV infection, the prevalence of cryptococcal infection, as determined by a positive serum cryptococcal antigen assay, was 2.9%.

Cryptococcal meningitis is a common AIDS-associated opportunistic infection worldwide. In sub-Saharan Africa, the median incidence is 3.2% among HIV-infected individuals; in 2011, the WHO recommended that patients there with HIV infection and CD4 counts <100 cells/mm3 be routinely screened for cryptococcal infection.

In the U.S., cryptococcal meningitis is much less common but still a problem; routine screening is not recommended in the most-recent version of the Guidelines for Prevention and Treatment of Opportunisitic Infections in HIV-Infected Adults and Adolescents. Now, researchers have examined the prevalence and outcomes of cryptococcal infection among AIDS patients in the U.S.

Using the cryptococcal antigen (CrAg) lateral flow assay, the investigators determined the presence of this antigen in 1872 stored serum samples collected between 1986 and 2012 from MACS and WIHS study participants with CD4 counts <100 cells/mm3. Prevalence of CrAg positivity was 2.9% overall and 2.5% among patients with no history of cryptococcal disease. Prevalence showed little variation by period of specimen collection but was significantly higher among participants with CD4 counts ≤50 cells/mm3 than among those with higher counts (4.3% vs. 1.7%). Having a positive CrAg result was associated with shorter survival (mean, 2.8 years vs. 3.8 years after specimen collection).

Citation(s):

McKenney J et al. Prevalence, correlates, and outcomes of cryptococcal antigen positivity among AIDS patients, United States from 1986–2012. Clin Infect Dis 2014 Nov 24; [e-pub ahead of print].