This paper provides an in-depth review of the methodological characteristics and study quality of childhood TB biomarkers, and compares the reported diagnostic performances to WHO-endorsed target product profiles for new diagnostics in children with presumptive tuberculosis (TPPs). It also gives targeted guidance for future biomarker studies, including the crucial need for adaptability of a promising signature in a given location to other geographical locations. The review was done, by Dr Toyin Omotayo Togun, Emily MacLean, Professor Beate Kampmann and  Madhukar Pai. Dr Togun was a PhD student at the MRC Unit The Gambia at LSHTM working on biomarkers for TB diagnostics in children and now post doc at McGill University in Canada with Professor Pai, where our collaborations continue.

The systematic review looked at 29 studies comprised of 20 case- control studies, six cohort studies and three cross-sectional studies. These studies reported diverse and various forms of biomarkers requiring different types of clinical specimen and laboratory assays. However, the diagnostic performance of biomarkers reported in 22 studies met one or both of the WHO-recommended minimal targets of 66% sensitivity and 98% specificity for a new diagnostic test for TB disease in children, and/or 90% sensitivity and 70% specificity for a triage test.

Childhood tuberculosis (TB) is estimated to constitute about 10% of the TB caseload in high TB burden countries. Studies have shown that majority of the biomarkers for diagnosis of TB in children are promising but will need further refining and optimization to improve their performances. As new data are emerging, stronger emphasis should be placed on improving the design, quality and general reporting of future studies investigating TB biomarkers in children. This will help in the accuracy of results obtained.

To develop and evaluate novel biomarkers for childhood TB in one of the aims of the childhood TB research program in the Vaccines & Immunity Theme, led by Prof Kampmann.

This paper was first published in the https://journals.plos.org/plosone/article?id=10.1371/journal.pone.02040… on September 13th 2018