Background NICE released an updated Tuberculosis (TB) guideline in January 2016. Compared with the 2011 guideline this reduced the Mantoux threshold from 15 mm to 5 mm irrespective of BCG status, thus increasing the number of patients requiring assessment for latent TB infection (LTBI) and TB disease. In 2015 we predicted a paediatric workload increase of 37%.¹

Objectives To determine the impact of the 2016 guideline on the number of children diagnosed with LTBI and TB disease.

Methods A retrospective analysis of children aged <16 years attending our TB service January-December 2016. All children were assessed by a TB nurse followed by a consultant if there were concerns about LTBI or TB disease. Management followed 2016 NICE guidelines. Treatment given was then compared with that recommended in the 2011 guidelines.

Results 411 children were seen by the TB nurse. Of these, 294/411 fulfilled the 2016 criteria for screening (new entrants and pulmonary contacts). 50/294 (17%) had a positive Mantoux. Based on Mantoux Results 40/294 (14%) were diagnosed with LTBI. 9/294 (3%) had TB disease. Following the 2011 guideline 22/294 (7%) had a positive Mantoux with 16/294 (5%) treated for LTBI and 6/294 (2%) for TB disease. Of those with positive Mantoux tests, IGRA tests were positive in 20/40 (50%) and 14/22 (64%) of the 2011 and 2016 guideline groups respectively (Table 1). 43 additional children (household contacts of non-pulmonary disease) would have been screened by the 2011 but not the 2016 guideline. These children were seen in our clinic. None had TB disease but 8 had Mantoux≥5 mm (1 IGRA positive).

Conclusion Compared with the 2011 version, the NICE 2016 TB guideline more than doubles the number of children receiving chemoprophylaxis for LTBI but identifies 33% more children with TB disease. Not screening household contacts of non-pulmonary cases Results in a 14.6% reduction in referrals but also misses a significant number of children with a positive mantoux.

Reference

1. Turnbull Let al. Thorax 2015;70(3):A209.