Background: Tuberculosis(TB)-associated IRIS posed a substantial early complication following antiretroviral therapy (ART) in area with HIV-TB co-endemic. However, the outcome of TB-IRIS is not well defined.This study aimed to determine the incidence and outcome of paradoxical and unmasking TB-IRIS after ART initiation.
Methods: We performed a retrospective cohort study of HIV-infected patients starting ART at Siriraj Hospital between January 2010 and December 2013. Paradoxical and unmasking TB-IRIS was diagnosed using published case criteria. The outcome obtained were mortality, rate of hospitalization, the increment of CD4 cell count and the proportion of virological suppression at 6 months and 1 years of ART initiation.
Results: A total of 370 HIV-infected patients were included, with a mean age of 40.02 (SD 10.36). The median CD4 cell count at baseline was 44 cell/ mm3 (IQR 17.5-91.5). Of 120 patients whom TB were diagnosed before starting ART, 21(17.5%) developed paradoxical TB-RIS at a median time of 24 days (IQR 14-49). Of 250 patients who was not receiving TB treatment when ART was initiated, 18 (7.2%) experienced ART-associated TB, with a median time of 47.5 days (IQR 23-98). Of which, 13 (5.2%) was identified as unmasking TB-IRIS. Four of 370 (1.08%) patients died within one year after HAART initiation. Those who died did not develop TB-IRIS. As compared to those without IRIS, paradoxical (94 vs.114, p=0.365) and ART-associated TB (104 vs.114, p=0.43) had no difference in the increment of CD4 cell count, and the proportion of virological suppression at 6 months (88.9%, 93.3% vs. 88.8%, p=1.00). However, those with paradoxical TB-IRIS or ART associated TB were hospitalized within 6 months after ART more frequently than those without TB-IRIS (33.3%, 33.3% vs. 8.2%, respectively, p = 0.001) and required more invasive procedures than those without TB-IRIS (42.9%, 55.6% vs. 3.3%, respectively, p<0.001)
Conclusion: The occurrence of TB-IRIS is not uncommon. Even though patients with TB-IRIS were hospitalized and underwent an invasive procedure far more frequently than those without TB-IRIS, none of those died. ART should be provided early and fear of any type of IRIS should not be the reason to defer ART in area with HIV-TB co-endemic.