Latent tuberculosis may be missed by current screening practices: Analysis of interferon-gamma release assay results from a paediatric refugee clinic

(i) To determine the prevalence of latent tuberculosis infection (LTBI) and characteristics associated with LTBI in children attending a paediatric refugee clinic and (ii) to determine whether current New South Wales (NSW) Health screening practices could miss LTBI cases.

This was a retrospective analysis of tuberculosis (TB) screening data from refugee and asylum seeker children who attended a refugee clinic in a tertiary children's hospital during 2014 and 2015. We determined associations between LTBI and child characteristics at 5% significance levels.

Of 358 children attending the clinic, 235 children (66%) received interferon-gamma release assay (IGRA) testing, of whom 28 (11.9%) had positive results. Of the 28 with positive IGRAs, 12 (42.9%) would have been missed using NSW Health screening guidelines: two because they were younger than 2 years old, one who was born in Australia and 10 because they were not born in high TB incidence countries. IGRA results were not significantly associated with any of the child characteristics examined, including age, gender, travel through transit countries, boat versus plane arrival into Australia, whether the child had been in a detention centre or TB incidence in the source country.

We identified 12 children with LTBI who would have been missed using current NSW Health Department screening practices. These children are at risk of progression to active disease, particularly the two aged younger than 2 years old. We recommend universal screening.