Prospective head-to-head study comparing 2 commercial interferon gamma release assays for the diagnosis of tuberculous uveitis

Am J Ophthalmol. 2014 Jun;157(6):1306-14; 1314.e1-4. doi: 10.1016/j.ajo.2014.01.031. Epub 2014 Feb 4.

Abstract

Purpose: To perform a head-to-head comparison of 2 commercially available interferon-gamma release assays, QuantiFERON-TB Gold In-Tube (Cellestis, Chadstone, Victoria, Australia) and T-SPOT.TB (Oxford Immunotech, Abingdon, Oxfordshire, UK), in the diagnosis of tuberculous uveitis.

Design: Prospective cohort to study diagnostic accuracy.

Methods: We recruited consecutive new patients who presented with uveitis to a tertiary institution over a 2-year period. All patients underwent complete ocular examination and systemic evaluation, including T-SPOT.TB, QuantiFERON-TB Gold In-Tube, and tuberculin skin test. Patients were followed-up for a minimum of 1 year after completion of antituberculous therapy where indicated. The main outcome measures were the sensitivity, specificity and accuracy of each test, estimated using Bayesian latent class analysis (presented with 95% Bayesian credible intervals) (Crl). Prior information was obtained from published meta-analyses for diagnostic tests: QuantiFERON Gold In-Tube sensitivity (0.64, 0.59-0.69) and specificity (0.99, 0.99-1.00); T-SPOT. tuberculosis sensitivity (0.50, 0.33-0.67) and specificity (0.91, 0.88-0.93).

Results: From our study in patients with uveitis, QuantiFERON-TB Gold In-Tube was more specific but slightly less sensitive (sensitivity: 0.64, 0.60-0.69; specificity: 0.995, 0.988-0.999) than T-SPOT.TB (sensitivity: 0.67, 0.60-0.74; specificity: 0.91, 0.88-0.93). However, QuantiFERON Gold In-Tube was significantly more accurate in identifying true-positive tuberculous uveitis cases than was T-SPOT.TB among discordant cases (QuantiFERON Gold In-Tube positive 98% vs T-SPOT.TB positive 76%; ratio 1.28, 95% Crl: 1.11-1.72, ie, 95% Crl >1.0, statistically significant).

Conclusion: Based on statistical decision theory, our head-to-head study suggests that QuantiFERON-TB Gold In-Tube is the first-line test that should be performed in preference to T-SPOT.TB (and the tuberculin skin test) for diagnosing tuberculous uveitis.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antitubercular Agents / therapeutic use
  • Drug Therapy, Combination
  • Enzyme-Linked Immunosorbent Assay
  • False Positive Reactions
  • Female
  • Follow-Up Studies
  • Glucocorticoids / therapeutic use
  • Humans
  • Interferon-gamma / blood
  • Interferon-gamma Release Tests*
  • Male
  • Middle Aged
  • Mycobacterium tuberculosis / isolation & purification
  • Predictive Value of Tests
  • Prednisolone / therapeutic use
  • Prospective Studies
  • Reagent Kits, Diagnostic
  • Reproducibility of Results
  • Sensitivity and Specificity
  • T-Lymphocytes / immunology
  • Tuberculin Test
  • Tuberculosis, Ocular / diagnosis*
  • Tuberculosis, Ocular / drug therapy
  • Tuberculosis, Ocular / microbiology
  • Uveitis / diagnosis*
  • Uveitis / drug therapy
  • Uveitis / microbiology

Substances

  • Antitubercular Agents
  • Glucocorticoids
  • Reagent Kits, Diagnostic
  • Interferon-gamma
  • Prednisolone