Stages of pregnancy and HIV affect diagnosis of tuberculosis infection and Mycobacterium tuberculosis (MTB)-induced immune response: Findings from PRACHITi, a cohort study in Pune, India. (November 2021)

• Record Type: Journal Article
• Authors: Bhosale, Ramesh; Alexander, Mallika; Deshpande, Prasad; Kulkarni, Vandana; Gupte, Nikhil; Gupta, Amita; Mathad, Jyoti
• Is Part Of: International journal of infectious diseases. Volume 112(2021)
• Page Start: 205
• Page End: 211
• Publication Date: 2021-11
• Subjects: Tubercular Infection (TBI) -- Interferon Gamma Release Assay (IGRA) -- Tuberculin Skin Test (TST) -- pregnancy, Human Immune Deficiency Virus (HIV) -- Interferon Gamma (IFN-γ); Communicable diseases -- Periodicals; Communicable Diseases -- Periodicals; Communicable diseases; Periodicals; Electronic journals; 616.9
• DOI: 10.1016/j.ijid.2021.09.010
• Languages: English
• ISSNs: 1201-9712

Abstract

Highlights: Pregnancy stage and HIV status impacted results of tuberculosis infection tests. IFN γ response was lower in HIV+ women at pregnancy stages relative to HIV- women. IFN γ response was lowest at delivery for both HIV+ and HIV- women. IGRA/TST agreement was lower in HIV+ women than HIV- at pregnancy and delivery. HIV+ and IGRA-positive pregnant women are at high risk of TB post-partum Abstract: Background: Accurate tuberculosis infection (TBI) tests are critical for pregnant women, especially those with HIV, who have a high risk of TB disease. Methods: We enrolled interferon gamma release assay (IGRA)+ pregnant women with and without HIV in a longitudinal study, followed up at delivery and 6 months postpartum. Tuberculin skin test (TST) and IGRA were compared by HIV status at each timepoint. Results: Of 165 enrolled IGRA+ pregnant women: 35 (21%) had HIV and were on antiretroviral therapy with median CD4 of 476 (IQR 399–586). Compared to antepartum, significantly fewer women remained IGRA+ at delivery [HIV+ n=21/35 (62%, p=0.009); HIV- n=100/130 (77%, p=0.002)] and postpartum [HIV+ n=30/35 (87%, p=0.03); HIV– n=116/130 (89%, p=0.01)]. IGRA/TST discordance was high in pregnant women (HIV+: 51%; HIV-: 25%). Median IFN-γ was lowest for all women at delivery; significantly lower in women with HIV at all timepoints compared to women without HIV. TB incidence was 50/ 1000 person-years and 18/1000 person-years among women with and without HIV respectively. Conclusions: Pregnancy affects TBI test results and reduces IFN-γ response to M. tuberculosis stimulation. Despite adequate CD4 counts, women with HIV express less IFN-γ than women without HIV, which may explain the high TB incidence in postpartum women with HIV.