Pregnancy suppresses Mycobacterium tuberculosis-specific Th1, but not Th2, cell-mediated functional immune responses during HIV/latent TB co-infection

Latent Tuberculosis Infection Status of Pregnant Women in Uganda Determined Using QuantiFERON TB Gold-Plus

“…This finding is consistent with published case series, which shows that the risk of TB in HIV-infected pregnant women appears to be higher, with 1%–11% developing active TB during pregnancy or the early postpartum period [ 22 , 24 ]. However, recent work has shown that despite the high TB incidence among HIV-positive individuals, detection of LTBI among these individuals is lower [ 8 ]. In Africa, WHO estimates revealed that TB rates are up to 10 times higher in pregnant women living with HIV than in pregnant women without HIV infection [ 3 ].…”

“…One study from Tanzania found a prevalence of LTBI among pregnant women as high as 37.4% [ 7 ]. Two studies from Ethiopia showed a prevalence of LTBI of 31.9% [ 8 ] and 33% [ 9 ] among pregnant women using IGRA.…”

Effect of pregnancy and HIV infection on detection of latent TB infection by Tuberculin Skin Test and QuantiFERON-TB Gold In-Tube assay among women living in a high TB and HIV burden setting

“…However, the risk of developing active TB as a result of reactivation of the LTBI could substantially increase in the presence of several predisposing factors such as Human immunodeficiency virus (HIV) infection and pregnancy (World Health Organization, 2019;Jonsson et al, 2020). HIV infection diminishes the Th1 cell-mediated immune response Abbreviations: TB, tuberculosis; LTBI, latent tuberculosis infection; HIV, Human immunodeficiency virus; M. tuberculosis, Mycobacterium tuberculosis; CD, cluster of differentiation; IFN, interferon; BCG, Bacille Calmette-Guérin; TST, tuberculin skin test; ELISA, enzyme-linked immunosorbent assay; QFTGIT, QuantiFERON-TB Gold In-Tube; PPD, purified protein derivative; ESAT-6, Early secreted antigen target-6; CFP-10, Culture filtrate protein-10; IQR, interquartile range; CDC, Center for Disease Control and Prevention; WHO, World Health Organization. to M. tuberculosis, while pregnancy deepens this suppression of anti-mycobacterial responses in HIV-positive individuals (Birku et al, 2020;Amelio et al, 2019;Mofenson and Laughon, 2007). This shows that the co-existence of HIV and pregnancy markedly suppresses M. tuberculosis-specific functional immune responses, thereby increasing the risk of progression of LTBI to active TB.…”

“…The diameter of induration was measured after 48-72 h by well-experienced nurses. The TST response was considered positive when the induration was at least 5 mm for HIV-positive participants and 10 mm for HIV-negative participants (World Health Organization, 2019;Birku et al, 2020;Cohn et al, 2000;Lin et al, 2016).…”

“…A blood sample of study participants was further tested using QFTGIT assay kits (Cellestis Limited, Australia) according to the manufacturer's protocol (Birku et al, 2020;LaCourse et al, 2017). Of the sample, 1 ml was collected in three QFTGIT evacuated tubes supplied by the manufacturerone containing M. tuberculosis antigens (ESAT-6, CFP-10 and TB7.7), a positive control tube containing phytohemagglutinin and a negative control tube, incubated overnight at 37 Cplasma was collected and stored at À20 C. When required, frozen plasma was thawed, and ELISA for IFN-g measurement was performed according to the QFTGIT kit.…”