Cryptococcal Antigen Screening and Early Antifungal Treatment to Prevent Cryptococcal Meningitis: A Review of the Literature

Background:Screening individuals with AIDS for serum cryptococcal antigen (CrAg), followed by treatment of CrAg positives with antifungals, may prevent cryptococcal meningitis. This review examined data on CrAg screening and treatment in resource-limited settings.Methods:We searched articles published during 2007-2014 on the effectiveness and cost-effectiveness of CrAg screening and treatment on the outcomes of mortality, morbidity, retention in care, quality of life, and/or prevention of ongoing HIV transmission. We rated overall quality of individual articles, summarized the body of evidence, the expected impact, and cost-effectiveness for each outcome.Results:We identified 2613 articles. Eight met all inclusion criteria. Five studies addressed mortality and/or morbidity outcomes; all were observational and had small sample sizes; 3 lacked a comparison group. Ratings of study quality ranged from medium to weak, and the quality of the overall body of evidence for mortality and morbidity outcomes was rated as fair. The intervention's expected impact on mortality and morbidity was rated as moderate. The 4 cost-effectiveness studies included in the analysis showed that CrAg screening and treatment interventions are highly cost-effective. No studies addressed retention in care, quality of life, or HIV transmission.Conclusions:Although limited, the body of evidence regarding CrAg screening and treatment suggests that the intervention may have an impact on preventing cryptococcal meningitis and death in persons with AIDS. Additional research is needed to quantify the intervention's effectiveness and identify optimal treatment dosing and implementation best practices.