Interferon-Gamma Release Assays for the Diagnosis of Latent Tuberculosis Infection in HIV-Infected Individuals: A Systematic Review and Meta-Analysis

Abstract

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 May2010 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. In3 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.

QuantiFERON-TB Gold In-Tube Test for Tuberculosis Prevention in HIV-Infected Patients

“…Although IGRAs are more sensitive and specific than TST in persons without HIV infection (6), a change from positive to negative results within both short and long-term periods were observed in PLWHIV with no or low TB risk (7,8). A meta-analysis of studies assessing TST and IGRA for LTBI screening among HIV-infected individuals demonstrated comparable performance between both tests (2). However, significant heterogeneity was noted among the studies included in this metaanalytic reports.…”

“…However, significant heterogeneity was noted among the studies included in this metaanalytic reports. In addition, the outcomes evaluated the predictive value of IGRA for active TB development and IGRA sensitivity in individuals using culture confirmation of active TB in comparison with TST (2). More longitudinal studies evaluating IPT efficacy based on positive TST, with or without IGRA testing in PLWHIV from high-endemic TB countries, are needed for evidence-based treatment strategies.…”

“…People living with human immunodeficiency virus (PLWHIV) who also have latent tuberculosis infection (LTBI) are at a greater risk for developing tuberculosis (TB) than those without HIV infection (1,2). The World Health Organization (WHO) recommended screening and isoniazid preventive therapy (IPT) for PLWHIV co-infected with LTBI given a 62 reduction in incidence of TB (1,3).…”

New Advances in Diagnosis of Latent Tuberculosis Infection: A Review Article

“…The Pulmonary Medicine 5 seems to be slightly less affected by immunosuppression (19). However, only five studies compared their sensitivity head to head (32)(33)(34)(35)(36), with only one study showing Quantiferon GIT QFT-GIT with a greater sensitivity than T-SPOT.TB in PLWHA (36). A prospective study from Iran (by Mardani et al) compared TST and Quantiferon TB gold in 50 HIV positive patients.…”

Usefulness of the Combination of Tuberculin Skin Test and Interferon-Gamma Release Assay in Diagnosing Children with Tuberculosis

“…We selected T-SPOT because this method has higher sensitivity in immunosuppressive conditions (Komiya et al 2010;Cattamanchi et al 2011) and requires less blood volume. At least 5 ml of venous blood was collected into a heparinized blood-collecting tube which was performed along with blood cell count and biochemical examination, and the blood samples were outsourced for the assay.…”