Multi-country evaluation of RISK6, a 6-gene blood transcriptomic signature, for tuberculosis diagnosis and treatment monitoring

Sci Rep. 2021 Jul 1;11(1):13646. doi: 10.1038/s41598-021-93059-1.

Abstract

There is a crucial need for non-sputum-based TB tests. Here, we evaluate the performance of RISK6, a human-blood transcriptomic signature, for TB screening, triage and treatment monitoring. RISK6 performance was also compared to that of two IGRAs: one based on RD1 antigens (QuantiFERON-TB Gold Plus, QFT-P, Qiagen) and one on recombinant M. tuberculosis HBHA expressed in Mycobacterium smegmatis (IGRA-rmsHBHA). In this multicenter prospective nested case-control study conducted in Bangladesh, Georgia, Lebanon and Madagascar, adult non-immunocompromised patients with bacteriologically confirmed active pulmonary TB (ATB), latent TB infection (LTBI) and healthy donors (HD) were enrolled. ATB patients were followed-up during and after treatment. Blood RISK6 scores were assessed using quantitative real-time PCR and evaluated by area under the receiver-operating characteristic curve (ROC AUC). RISK6 performance to discriminate ATB from HD reached an AUC of 0.94 (95% CI 0.89-0.99), with 90.9% sensitivity and 87.8% specificity, thus achieving the minimal WHO target product profile for a non-sputum-based TB screening test. Besides, RISK6 yielded an AUC of 0.93 (95% CI 0.85-1) with 90.9% sensitivity and 88.5% specificity for discriminating ATB from LTBI. Moreover, RISK6 showed higher performance (AUC 0.90, 95% CI 0.85-0.94) than IGRA-rmsHBHA (AUC 0.75, 95% CI 0.69-0.82) to differentiate TB infection stages. Finally, RISK6 signature scores significantly decreased after 2 months of TB treatment and continued to decrease gradually until the end of treatment reaching scores obtained in HD. We confirmed the performance of RISK6 signature as a triage TB test and its utility for treatment monitoring.

Publication types

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

MeSH terms

  • Adult
  • Case-Control Studies
  • Disease Management
  • Female
  • Humans
  • Latent Tuberculosis / blood
  • Latent Tuberculosis / diagnosis
  • Latent Tuberculosis / genetics
  • Latent Tuberculosis / therapy
  • Male
  • Mycobacterium tuberculosis / genetics*
  • Mycobacterium tuberculosis / isolation & purification
  • Prospective Studies
  • Transcriptome*
  • Triage
  • Tuberculosis / blood
  • Tuberculosis / diagnosis*
  • Tuberculosis / genetics
  • Tuberculosis / therapy
  • Tuberculosis, Pulmonary / blood
  • Tuberculosis, Pulmonary / diagnosis
  • Tuberculosis, Pulmonary / genetics
  • Tuberculosis, Pulmonary / therapy
  • Young Adult