Open AccessEstimated Prevalence of Cryptococcus Antigenemia (CrAg) among HIV-Infected Adults with Advanced Immunosuppression in Namibia Justifies Routine Screening and Preemptive Treatment
Author(s) -
Souleymane Sawadogo,
Boniface Makumbi,
Anne Purfield,
Christophine Ndjavera,
Gram Mutandi,
Andrew Maher,
Francina Kaindjee-Tjituka,
Jonathan E. Kaplan,
Benjamin J. Park,
David Lowrance
Publication year - 2016
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0161830
Subject(s) - medicine , immunosuppression , cryptococcal meningitis , human immunodeficiency virus (hiv) , meningitis , cross sectional study , young adult , immunology , pediatrics , gastroenterology , viral disease , pathology
Background Cryptococcal meningitis is common and associated with high mortality among HIV infected persons. The World Health Organization recommends that routine Cryptococcal antigen (CrAg) screening in ART-naïve adults with a CD4 + count <100 cells/μL followed by pre-emptive antifungal therapy for CrAg-positive patients be considered where CrAg prevalence is ≥3%. The prevalence of CrAg among HIV adults in Namibia is unknown. We estimated CrAg prevalence among HIV-infected adults receiving care in Namibia for the purpose of informing routine screening strategies. Methods The study design was cross-sectional. De-identified plasma specimens collected for routine CD4 + testing from HIV-infected adults enrolled in HIV care at 181 public health facilities from November 2013 to January 2014 were identified at the national reference laboratory. Remnant plasma from specimens with CD4 + counts <200 cells/μL were sampled and tested for CrAg using the IMMY ® Lateral Flow Assay. CrAg prevalence was estimated and assessed for associations with age, sex, and CD4 + count. Results A total of 825 specimens were tested for CrAg. The median (IQR) age of patients from whom specimens were collected was 38 (32–46) years, 45.9% were female and 62.9% of the specimens had CD4 <100 cells/μL. CrAg prevalence was 3.3% overall and 3.9% and 2.3% among samples with CD4 + counts of CD4 + <100 cells/μL and 100–200 cells/μL, respectively. CrAg positivity was significantly higher among patients with CD4+ cells/μL < 50 (7.2%, P = 0.001) relative to those with CD4 cells/μL 50–200 (2.2%). Conclusion This is the first study to estimate CrAg prevalence among HIV-infected patients in Namibia. CrAg prevalence of ≥3.0% among patients with CD4 + <100 cells/μL justifies routine CrAg screening and preemptive treatment among HIV-infected in Namibia in line with WHO recommendations. Patients with CD4 + <100 cells/μL have a significantly greater risk for CrAg positivity. Revised guidelines for ART in Namibia now recommend routine screening for CrAg.