Impact of HIV and peripartum period on Mycobacterium tuberculosis infection detection

Abstract

Background: Pregnancy and HIV may influence TB infection (TBI) detection using interferon gamma-release assays (QFT-Plus) and tuberculin skin tests (TST).

Methods: Participants from antenatal clinics in Western Kenya underwent QFT-Plus and TST in pregnancy, 6-weeks (6wkPP) and 12-months postpartum (12moPP).

Results: 400 participants (200 WHIV/200 HIV-negative) enrolled in pregnancy at median 28 weeks gestation (IQR 24-30).QFT-Plus + prevalence was higher than TST + in pregnancy (32.5% vs. 11.6%) and through 12moPP (6wkPP: QFT-Plus 30.9% vs. TST 18.0%, 12moPP: QFT-Plus 29.5% vs. TST 17.1%, all p < 0.001), driven primarily QFT-Plus+/TST- discordance among HIV-negative women.TBI test conversion incidence was 28.4/100PY, and higher in WHIV vs. HIV-negative women (35.5 vs. 20.9/100PY, HR 1.73 [95%CI 1.04-2.88]), mostly due to early postpartum TST conversion among WHIV.Among QFT-Plus + participants in pregnancy, Mtb-specific IFN-γ responses were dynamic from pregnancy to 12moPP and were lower among WHIV vs. HIV-negative women with TBI at all time points.

Conclusions: QFT-Plus had higher TBI diagnostic yield than TST in peripartum women with/without HIV. Peripartum QFT-Plus + prevalence was stable and less influenced by HIV than TST. Mtb-specific IFN-γ responses were dynamic and lower among WHIV. TBI test conversion incidence was high between pregnancy and early postpartum, potentially due to postpartum immune recovery.