BACKGROUND: Renal transplant recipients (RTRs), as all immunosuppressed patients, are at increased risk of reactivating latent tuberculosis infection (LTBI). Detecting LTBI in this population is therefore important to prevent active TB. The tuberculin skin test (TST) has a poor sensitivity in this setting. METHODS: The aim of this prospective study was to compare the diagnostic performance of the TST and two interferon-γ release assays (IGRAs): T-SPOT.TB (Oxford Immunotec, Oxford, UK) and QuantiFERON Gold In-Tube (QGIT; Cellestis, Australia), performed simultaneously, for the detection of patients with risk factors for LTBI or a definite history of TB among RTRs under stable immunosuppression. RESULTS: Two hundred five patients (ages 59±13 years, tested 10.4±7.1 years after transplantation) were studied. Positivity rate was 4.5% for TST, 20.5% for T-SPOT.TB, and 23.5% for QGIT. Agreement between IGRAs was fair (κ=0.71). Sensitivity of T-SPOT.TB and QGIT for detection of prior active TB was 55.6% (95% confidence interval [CI], 21.2-86.3) and 44.4 (95% CI, 13.7-78.8), respectively. Sensitivity of both IGRAs for detection of risk factors for LTBI was 33.3% (95% CI, 19.6-49.5). Specificity was 85.5% (95% CI, 78.9-90.7) for T-SPOT.TB and 80.1% (95% CI, 72.9-86.2) for QGIT. Combining IGRAs did not significantly improve sensitivity. CONCLUSIONS: Because their sensitivity for detecting prior active TB and probable LTBI in RTRs is very low, IGRAs cannot be used to exclude LTBI. These results emphasize the limitations of IGRAs in the setting of chronic immunosuppressive therapy.
BACKGROUND: Renal transplant recipients (RTRs), as all immunosuppressed patients, are at increased risk of reactivating latent tuberculosis infection (LTBI). Detecting LTBI in this population is therefore important to prevent active TB. The tuberculin skin test (TST) has a poor sensitivity in this setting. METHODS: The aim of this prospective study was to compare the diagnostic performance of the TST and two interferon-γ release assays (IGRAs): T-SPOT.TB (Oxford Immunotec, Oxford, UK) and QuantiFERON Gold In-Tube (QGIT; Cellestis, Australia), performed simultaneously, for the detection of patients with risk factors for LTBI or a definite history of TB among RTRs under stable immunosuppression. RESULTS: Two hundred five patients (ages 59±13 years, tested 10.4±7.1 years after transplantation) were studied. Positivity rate was 4.5% for TST, 20.5% for T-SPOT.TB, and 23.5% for QGIT. Agreement between IGRAs was fair (κ=0.71). Sensitivity of T-SPOT.TB and QGIT for detection of prior active TB was 55.6% (95% confidence interval [CI], 21.2-86.3) and 44.4 (95% CI, 13.7-78.8), respectively. Sensitivity of both IGRAs for detection of risk factors for LTBI was 33.3% (95% CI, 19.6-49.5). Specificity was 85.5% (95% CI, 78.9-90.7) for T-SPOT.TB and 80.1% (95% CI, 72.9-86.2) for QGIT. Combining IGRAs did not significantly improve sensitivity. CONCLUSIONS: Because their sensitivity for detecting prior active TB and probable LTBI in RTRs is very low, IGRAs cannot be used to exclude LTBI. These results emphasize the limitations of IGRAs in the setting of chronic immunosuppressive therapy.
Authors: Balakrishnan S Ramakrishna; Govind K Makharia; Vineet Ahuja; Uday C Ghoshal; Venkataraman Jayanthi; Benjamin Perakath; Philip Abraham; Deepak K Bhasin; Shobna J Bhatia; Gourdas Choudhuri; Sunil Dadhich; Devendra Desai; Bhaba Dev Goswami; Sanjeev K Issar; Ajay K Jain; Rakesh Kochhar; Goundappa Loganathan; Sri Prakash Misra; C Ganesh Pai; Sujoy Pal; Mathew Philip; Anna Pulimood; Amarender S Puri; Gautam Ray; Shivaram P Singh; Ajit Sood; Venkatraman Subramanian Journal: Indian J Gastroenterol Date: 2015-03-14
Authors: Edward Barton; Yifang Gao; Darran Ball; Katy Fidler; Nigel Klein; Nigel Curtis; Vanessa Clifford; Ben G Marshall; Andrew Chancellor; Salah Mansour; Paul Elkington; Marc Tebruegge Journal: Ann Am Thorac Soc Date: 2019-06