At two hospitals in Southwest London comprising an international population with an African heterosexual predominance, there was a 5% prevalence of cryptococcal antigenemia in newly diagnosed patients with CD4 count < 100 cells/μL. Almost all of the CRAG positive patients were African, though the statistical power of the comparison of proportion of African patients between the CRAG positive (88%) and negative (54%) groups was limited by the cohort size. This relatively high prevalence of cryptococcal infection, on a par with some African countries, reflects our African HIV patient predominance, and may not
be generalizable to all UK HIV cohorts. Our numbers may also have been augmented by a tertiary centre referral bias of complex HIV patients AZD2281 manufacturer with advanced disease and CM for specialist Infectious Diseases inpatient care. Four of the 8 patients had been transferred to St George’s from hospitals in our sector, for whom we did not have a new HIV diagnoses denominator. Excluding those transfers would result in a conservative estimate of prevalence of cryptococcal infection in newly diagnosed HIV patients with CD4 < 100 cells/μL in southwest London of 3% (4/153), and 5% (4/84) in Africans. In our cohort, almost all the CRAG positive patients were only diagnosed with HIV at the time of presentation with CM. Late HIV diagnoses are not exclusive to resource-limited countries: in 2010, 28% of new UK HIV diagnoses
had CD4 counts < 200 cells/μL17 and in North America in 2008, 33% of newly HIV-diagnosed patients developed
AIDS Cyclopamine manufacturer within one year.18 By ethnicity, late presentation is highest amongst Black Africans,17 and the National Institute for Clinical Excellence is promoting increased HIV testing in this group.19 For our African CRAG positive patients with known time between arrival to the UK and new HIV diagnosis, this ranged from 5 to 16 years, suggesting opportunities for earlier HIV diagnosis and ART, which might have prevented dissemination of latent cryptococcal infection occurring at lower CD4 counts. For those diagnosed late, the question remains whether CRAG screening at HIV diagnosis should be routinely recommended. To be effective, screening needs to be done prior to symptomatic presentation within the antigenemic window, which ranges from weeks to months.8 Current BHIVA guidelines20 recommend RG7420 order excluding cryptococcal infection in symptomatic patients with CD4 < 200 cells/μL but do not advocate routine screening or fluconazole prophylaxis. CM is not a reportable disease: HPA figures of new CM diagnoses in the UK between 2006 and 2011 range from 5 to 28 cases/year, suggesting significant underreporting [C Chau, Health Protection Agency HIV&STI department, personal communication]. Based on these figures and our relatively high prevalence in a London cohort, it is difficult to extrapolate to recommendations for targeted screening in the UK.