Latent TB detection by interferon gamma release assay (IGRA) in pregnancy predicts active TB and mortality in HIV-1 infected women and their children

Abstract

Background—We evaluated the prognostic utility of interferon-gamma release assays (IGRAs) for active tuberculosis (TB) and mortality in Kenyan HIV-1 infected women and their infants. Methods—Prevalence and correlates of Mycobacterium tuberculosis-specific T-SPOT.TB IGRA positivity were determined during pregnancy in a historical cohort of HIV-1 infected women. Hazard ratios, adjusted for baseline maternal CD4 count (aHRCD4) were calculated for associations between IGRA positivity and risk of active TB and mortality over 2-year postpartum follow-up in women and their infants. Results—Of 333 women tested, 52 (15.6%) had indeterminate IGRAs. Of the remaining 281 women, 120 (42.7%) had positive IGRAs, which were associated with a 4.5-fold increased risk of active TB [aHRCD4: 4.5; 95% confidence interval (CI): 1.1–18.0; p=0.03]. Among immunosuppresed women (CD4<250 cell/mm3), positive IGRAs were associated with increased risk of maternal mortality (aHRCD4: 3.5; 95% CI: 1.02–12.1; p=0.045), maternal active TB or mortality (aHRCD4: 5.2; 95% CI: 1.7–15.6; p=0.004) and infant active TB or mortality, overall