Characteristics of paradoxical tuberculosis-associated immune reconstitution inflammatory syndrome and its influence on tuberculosis treatment outcomes in persons living with HIV.

OBJECTIVE: The influence of tuberculosis (TB)-immune reconstitution inflammatory syndrome (IRIS) on TB treatment outcomes and its risk factors were investigated among people with human immunodeficiency virus (HIV) and co-infected with TB. METHODS: Newly diagnosed, culture-confirmed, pulmonary TB patients with HIV and enrolled in a clinical trial (NCT00933790) were retrospectively analysed for IRIS occurrence. Risk factors and TB outcomes (up to 18 months after initiation of anti-TB treatment [ATT]) were compared between people who experienced IRIS (IRIS group) and those who did not (non-IRIS group). RESULTS: TB-IRIS occurred in 82 of 292 (28%) participants. Significant baseline risk factors predisposing to TB-IRIS occurrence in univariate analysis were: lower CD4+ T-cell count, CD4/CD8 ratio, haemoglobin levels, presence of extra-pulmonary TB focus, and higher HIV viral load; the last two retained significance in the multivariate analysis. After 2 months of ATT commencement, sputum smear conversion was documented in 45 of 80 (56.2%) vs. 124 of 194 (63.9%) (p=0.23), culture conversion was in 75 of 80 (93.7%) vs. 178 of 194 (91.7%) (p=0.57) and the median decline in viral load (log10copies/mm3) was 2.7 in the IRIS vs. 1.1 in the non-IRIS groups (p<0.0001), respectively. An unfavourable response to TB therapy was detected in 17 of 82 (20.7%) and 28 of 210 (13.3%) in the IRIS and non-IRIS groups, respectively (p=0.14). CONCLUSIONS: TB-IRIS frequently occurred in people with advanced HIV infection and in those who presented with extra-pulmonary TB lesions, without influencing subsequent TB treatment outcomes.

Paradoxical tuberculosis immune reconstitution inflammatory syndrome (TB-IRIS) in HIV patients with culture confirmed pulmonary tuberculosis in India and the potential role of IL-6 in prediction.

BACKGROUND: The incidence, manifestations, outcome and clinical predictors of paradoxical TB-IRIS in patients with HIV and culture confirmed pulmonary tuberculosis (PTB) in India have not been studied prospectively. METHODS: HIV+ patients with culture confirmed PTB started on anti-tuberculosis therapy (ATT) were followed prospectively after anti-retroviral therapy (ART) initiation. Established criteria for IRIS diagnosis were used including decline in plasma HIV RNA at IRIS event. Pre-ART plasma levels of interleukin (IL)-6 and C-reactive protein (CRP) were measured. Univariate and multivariate logistic regression models were used to evaluate associations between baseline variables and IRIS. RESULTS: Of 57 patients enrolled, 48 had complete follow up data. Median ATT-ART interval was 28 days (interquartile range, IQR 14-47). IRIS events occurred in 26 patients (54.2%) at a median of 11 days (IQR: 7-16) after ART initiation. Corticosteroids were required for treatment of most IRIS events that resolved within a median of 13 days (IQR: 9-23). Two patients died due to CNS TB-IRIS. Lower CD4(+) T-cell counts, higher plasma HIV RNA levels, lower CD4/CD8 ratio, lower hemoglobin, shorter ATT to ART interval, extra-pulmonary or miliary TB and higher plasma IL-6 and CRP levels at baseline were associated with paradoxical TB-IRIS in the univariate analysis. Shorter ATT to ART interval, lower hemoglobin and higher IL-6 and CRP levels remained significant in the multivariate analysis. CONCLUSION: Paradoxical TB-IRIS frequently complicates HIV-TB therapy in India. IL-6 and CRP may assist in predicting IRIS events and serve as potential targets for immune interventions.