Implementation and Evaluation of a Screening Strategy to Reduce Morbidity and Mortality Due to Cryptoccocal Meningo-encephalitis in ART Naive AIDS Patients With <100 CD4 Count at the Day Hospital of the Yaounde Central Hospital, Cameroon

Cryptococcal meningitis (CM) is a leading cause of death in AIDS patients in much of the developing world, responsible for up to 500,000 deaths each year in sub-Saharan Africa alone. Introduction of antiretroviral therapy (ART) has reduced the number of cases of cryptococcal meningitis in the developed world. Unfortunately, in many low resource settings, patients continue to present late to ART treatment programs with advanced immunosuppression, and many die of HIV-related illness in the weeks just prior to, and months following, initiation of ART. Cryptococcal meningitis causes many of these deaths, and is also a heavy burden on healthcare facilities. Treatment of the disease remains inadequate, with an acute mortality of between 20 and 50%, even with the best current treatment.

Many of these cases of cryptococcal meningitis may be preventable. Recent research has shown that routine screening for sub-clinical infection, using a simple test (cryptococcal antigen or CRAG) in patients presenting to ART programmes, can identify which patients are at risk of developing cryptococcal meningitis. Once identified, these patients could then be given safe oral "pre-emptive" treatment to prevent them developing a severe form of the disease. This strategy has many advantages over the alternative preventative measure, called generalised primary prophylaxis, which involves giving all profoundly immune depressed HIV-infected patients preventative treatment. Using a primary prophylaxis strategy, large numbers of patients are given medication, many of whom don't need it, and there are problems of cost and development of drug resistance and drug interactions. In a targeted strategy, only patients who benefit most from the treatment will be given medication.

The investigators propose to study the feasibility and effectiveness of CRAG screening and targeted pre-emptive treatment in patients entering ART treatment programmes in Yaoundé, Cameroon using a newly approved, easier to use, lateral flow format dipstick test (LFA). In the planned study, 400 patients will be screened using the CRAG test prior to starting ART. Patients with a positive cryptococcal antigen will be consented for a lumbar puncture (LP) for cerebrospinal fluid (CSF) analysis, and, if found to have cryptococcal meningitis, and eligible, they will be randomised and included in the complementary clinical trial "Advancing Cryptococcal Treatment in Africa" (ACTA) [ISRCTN45035509, ANRS12275] and treated according to the study protocol. Positive cryptococcal antigen patients with no evidence of neurological disease following lumbar puncture, or who decline a diagnostic LP will receive a tapering course of fluconazole. Cryptococcal antigen negative patients will not receive any additional antifungal therapy. All CRAG screened patients will be started on standard ART 2 to 4 weeks after screening and followed for up to 1 year, depending on antigen status, to determine whether any patients go on to develop clinical cryptococcal meningitis.

General objective

• To implement and evaluate systematic cryptococcal antigen screening as a strategy to reduce cryptococcal meningoencephalitis morbidity and mortality among HIV-infected patients initiating antiretroviral therapy at less than 100 CD4 cell counts at the Day Hospital of the Yaoundé Central Hospital in Cameroon