Contact tracing in pulmonary versus non-pulmonary tuberculosis- the impact of the 2016 NICE guidelines?

Aim: The UK guidance for contact tracing in TB was updated in 2016 and recommends against contact tracing in patients with non-pulmonary (NP) TB (1). Based on anecdotal and published evidence there are substantial numbers of positive screening episodes in NP TB contacts (2). The aim of our study was to evaluate the impact of the new guidelines on the number of new TB cases that would be missed in the NP TB contacts if guidelines were implemented. Methods: We performed an audit of TB contact tracing in Royal Bolton Hospital in 2014-2015. We identified index cases and determined the site as P or NP as per NICE definitions. The number of contacts identified and screened was recorded. A positive screen was defined as either active or latent TB as per national guidelines (1). Results: The number of positive screening episodes for P-TB was 23.3% (active TB 2.1% and latent TB 21.2%). The total positive screening episodes for NP-TB was 6.2% (active TB 2.1% and latent TB 4.1%) but was 10.9% in adult contacts. Conclusion: Contact tracing in NP-TB patients produced significant numbers of positive screens and had comparable levels of active TB to the P-TB contacts. This evidence supports our decision to continue contact screening in NP-TB until more robust evidence is available. References: 1) NICE. Tuberculosis, 2016 2) Mandal P et al. Contact tracing in pulmonary and non-pulmonary tuberculosis, QJM, 2012, 105(8): 741-747