Abstract
Our hospital has links with an Army base and investigates recruits for Tuberculosis (TB). Many come from high prevalence areas. Recruits are screened with a Mantoux test. Those with a Mantoux reaction ≥15mm and no previous BCG vaccination are referred for QuantiFERON Gold testing. If positive they are treated for latent TB.
We reviewed referrals over a 2 year period (April 2008 - April 2010) to assess compliance with Army policy and investigate whether referral based on Mantoux reaction alone is warranted.
Demographic data were gathered from Army records. The relationship between a positive QuantiFERON test and a Mantoux reaction of ≥15mm was assessed using a Chi-squared test.
153 cases were identified, 28 were excluded due to insufficient data, leaving a sample of 125. All cases were male. Median age was 21.5 years (range 17-33). For analysis recruits were divided into 4 areas (see table 1).
QuantiFERON and Mantoux results by Nationality
89 recruits (79%) had a positive QuantiFERON test. There was no significant relationship between QuantiFERON positivity and Mantoux size ≥ 15mm (p=0.0923).
Large numbers of recruits are referred based on their Mantoux results, including many with reactions of 6-14 mm. As there was no significant relationship between the rate of QuantiFERON positivity and Mantoux reaction size ≥ 15mm, referral decisions should not be made on this basis alone.
Further research is warranted to assess the current referral guidelines.
- © 2011 ERS