Cryptococcal Antigen Screening and Treatment: The Current State of Global Screening Programs to Prevent Death from Cryptococcal Infection

Abstract

Cryptococcal meningitis (CM) is the leading cause of death among people with AIDS. The World Health Organization issued a conditional recommendation in 2011 for countries to consider serum cryptococcal antigen (CrAg) screening in patients with CD4 count <100 cells/μL in order to identify those at risk for CM and to treat them preemptively with fluconazole to prevent progression to CM. This paper outlines the evidence behind CrAg screening, the prevalence of CrAg in various settings, and our current understanding of the state of CrAg screening programs. A growing number of countries are incorporating CrAg screening into their national HIV treatment guidelines and are beginning to implement national screening programs, while others are piloting in select regions to assess the feasibility of such programs. Strategies used to conduct CrAg screening, including reflexive laboratory-based screening, provider-initiated screening, and point-of-care screening, are also discussed. Countries considering large-scale rollout of CrAg screening should assess what combination of screening methods works best in their specific contexts.