Post TB Bronchiectasis:a distinct phenotype

<bold>Introduction:</bold> Bronchiectasis occurs frequently as a consequence of pulmonary tuberculosis. We investigated whether TB associated bronchiectasis has a distinct clinical phenotype using the EMBARC bronchiectasis registry. <bold>Methods:</bold> EMBARC is a prospective observational registry of adult patients with bronchiectasis from 31 countries. Patients were classified into two groups based on whether or not they had a history of pulmonary tuberculosis. Factors associated with pulmonary TB history were evaluated using logistic regression. <bold>Results:</bold> 19324 patients were included. Pulmonary TB was associated with a large number of individual factors in multivariate analysis including older age (OR 1.01 95%CI 1.01-1.02), a higher risk of P.aeruginosa infection (OR 1.18 95%CI 1.03-1.35), and a lower risk of H. influenzae infection (OR 0.69 95%CI 0.57-0.83). FEV1 was lower in TB patients (p<0.0001) and MRC dyspnoea score was higher (OR 1.07 95%CI 1.02-1.12). TB was associated with greater extent of radiological bronchiectasis in the right upper lobe (OR 1.36 95%CI 1.28-1.44) and left upper lobe (1.27 95%CI 1.19-1.35) with corresponding less severe bronchiectasis in the middle and lower lobes (all p<0.0001). Compared to the UK (reference), all other regions had a higher incidence of TB, Northern and Western Europe (OR 1.32 95%CI 1.10-1.59), Southern Europe (OR 1.83 95%CI 1.59-2.11), Eastern Europe (OR 2.32 95%CI 1.88-2.86) and Asia (OR 8.92 95%CI 7.63-10.42). Post-TB bronchiectasis was not associated with increased exacerbations or mortality during 5 years follow-up. <bold>Conclusion:</bold> Post TB bronchiectasis is associated with a clinical phenotype of older age, P. aeruginosa infection, worse lung function and dyspnoea, and upper lobar cystic lung disease.