Background. We evaluated the prognostic usefulness of interferon γ release assays (IGRAs) for active tuberculosis and mortality in Kenyan human immunodeficiency virus type 1 (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 cell count (aHRCD4), were calculated for associations between IGRA positivity and risk of active tuberculosis and mortality over 2-year postpartum follow-up among women and their infants.
Results. Of 333 women tested, 52 (15.6%) had indeterminate IGRA results. Of the remaining 281 women, 120 (42.7%) had positive IGRA results, which were associated with a 4.5-fold increased risk of active tuberculosis (aHRCD4, 4.5; 95% confidence interval [CI], 1.1–18.0; P = .030). For immunosuppressed women (CD4 cell count, <250 cells/µL), positive IGRA results were associated with increased risk of maternal mortality (aHRCD4, 3.5; 95% CI, 1.02–12.1; ), maternal active tuberculosis or mortality (aHRCD4
P = .045 , 5.2; 95% CI, 1.7–15.6; P = .004), and infant active tuberculosis or mortality overall (aHRCD4, 3.0; 95% CI, 1.0–8.9; P = .05) and among HIV-1-exposed uninfected infants (aHRCD4, 7.3; 95% CI, 1.6–33.5; P = .01).
Conclusions. Positive IGRA results for HIV-1-infected pregnant women were associated with postpartum active tuberculosis and mortality among mothers and their infants.