Cryptococcal meningitis diagnostics and screening in the era of point-of-care laboratory testing

Over the past ten years, standard diagnostics for cryptococcal meningitis in HIV-infected persons have evolved from culture, to India ink, to detection of cryptococcal antigen (CrAg) with the recent development and distribution of a point-of-care lateral flow assay. This assay is highly sensitive and specific in cerebrospinal fluid (CSF), but is also sensitive in the blood to detect CrAg prior to meningitis symptoms. CrAg screening in HIV-infected persons in the blood prior to development of fulminant meningitis, and preemptive treatment for CrAg-positive persons is recommended by the World Health Organization and many national HIV guidelines. Thus, CrAg testing is occurring more widely, especially in resource-limited laboratory settings. CrAg titer predicts meningitis and death, and could be used in the future to customize therapy according to burden of infection.