Cryptococcal antigen titers and semi-quantitative assay scores among people with HIV-associated cryptococcal antigenemia

A majority of patients with HIV-associated cryptococcal antigenemia identified through a large screening program in South Africa had high cryptococcal antigen titers and thus an elevated risk of concurrent meningitis and death. Despite this, a relatively small proportion had a lumbar puncture to definitively exclude meningitis. Routine CrAg semi-quantification can help to stratify patients at higher risk for meningitis and guide clinicians' management, but performing a full range of titers for all CrAg-positive blood samples increases costs and is labor-intensive. An alternative approach is to use a single test strip, which yields a semi-quantitative score.