OBJECTIVE:: To determine whether interferon-gamma release assays (IGRAs) improve the identification of HIV-infected individuals who could benefit from LTBI therapy.

DESIGN:: Systematic review and meta-analysis.

METHODS:: We searched multiple databases through May 2010 for studies evaluating the performance of the newest commercial IGRAs (QuantiFERON-Gold In-tube [QFT-GIT] and T-SPOT.TB [TSPOT]) in HIV-infected individuals. We assessed the quality of all studies included in the review, summarized results in pre-specified sub-groups using forest plots, and where appropriate, calculated pooled estimates using random effects models.

RESULTS:: The search identified 37 studies that included 5736 HIV-infected individuals. In 3 longitudinal studies, the risk of active TB was higher in HIV-infected individuals with positive versus negative IGRA results. However, the risk difference was not statistically significant in the 2 studies that reported IGRA results according to manufacturer-recommended criteria. In persons with active TB (a surrogate reference standard for LTBI), pooled sensitivity estimates were heterogeneous, but higher for TSPOT (72%, 95% CI 62-81%) than for QFT-GIT (61%, 95% CI 41-75%). However, neither IGRA was consistently more sensitive than the tuberculin skin test (TST) in head-to-head comparisons. While TSPOT appeared to be less affected by immunosuppression than QFT-GIT and TST, overall, differences between the three tests were small or inconclusive.

CONCLUSIONS:: Current evidence suggests that IGRAs perform similarly to the TST at identifying HIV-infected individuals with LTBI. Given that both tests have modest predictive value and sub-optimal sensitivity, the decision to use either test should be based on country guidelines and resource and logistical considerations.

J Acquir Immune Defic Syndr. 2010 Dec 25;
Authors: Cattamanchi A, Smith R, Steingart KR, Metcalfe JZ, Date A, Coleman C, Marston BJ, Huang L, Hopewell PC, Pai M
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