Journal Article

C-Tb skin test to diagnose Mycobacterium tuberculosis infection in children and HIV-infected adults: A phase 3 trial

Borregaard, Bettine, Seopela, Vincent, Andersen, Peter, Hoff, Søren T., Lourens, Madeleine, Ruhwald, Morten, Hellstrom, Elizabeth, Dheda, Keertan, Malahleha, Mookho, Gani, Mashra, Aggerbeck, Henrik, Diacon, Andreas, Siebert, Mirna

2018

Overview

C-Tb, an ESAT-6/CFP-10-based skin test, has similar sensitivity for active TB compared to tuberculin skin test (TST) and QuantiFERON-TB-Gold-In-Tube (QFT). However, data are limited in children and HIV-infected persons. Asymptomatic South African contacts <5 years (n = 87; HIV-uninfected), or symptomatic individuals of all ages presenting to clinics with suspected TB (n = 1003; 30% HIV-infected) were recruited from eight South African centres. C-Tb and TST were allocated to either forearm double blinded. Samples for QFT were collected in parallel, and test-positivity rates were compared. In participants with microbiologically confirmed TB (n = 75; 45% HIV-infected) sensitivity of C-Tb, TST and QFT were similar (72% versus 75% versus 73%; p>0.5). All 3 tests had similar positivity rates in HIV-infected participants with active TB, however, positivity rates were reduced when CD4 counts were <100 cells/μL. In participants where active TB was excluded (n = 920), C-Tb (41%), TST (43%), and QFT (44%) also had similar test-positivity rates. Among asymptomatic contacts aged below five, 32% (28/87) tested positive with C-Tb and 32% (28/87) with TST (concordance 89%). Overall, C-Tb and TST showed a similar safety profile. C-Tb was safe and showed similar test-positivity rates, compared to TST and QFT, in children and HIV-infected persons with active or latent M. tuberculosis infection. These data inform the utility of C-Tb in clinical practice. ClinicalTrials.gov NCT01642888. EudraCT 2011-005078-40.

• Publisher: Public Library of Science,Public Library of Science (PLoS)
• Subject: Adolescent / Adult / Adults / Aged / Analysis / Antigens / Biology and Life Sciences / Care and treatment / CD4 antigen / Child / Child, Preschool / Children / Clinical trials / Coinfection - diagnosis / Double-Blind Method / ESAT-6 antigen / Female / Forearm / Gold / Health aspects / HIV / HIV Infections - complications / HIV Infections - diagnosis / Human immunodeficiency virus / Humans / Immunology / Infant / Infant, Newborn / Infections / Infectious diseases / Male / Medical diagnosis / Medicine and Health Sciences / Middle Aged / Mycobacteria / Pediatric HIV infections / Sensitivity / Sensitivity and Specificity / Skin / Skin tests / Skin Tests - methods / Systematic review / Tuberculin / Tuberculosis / Tuberculosis - complications / Tuberculosis - diagnosis / Ultrasonic testing / Young Adult