Latent TB infection and pulmonary TB disease among patients with diabetes mellitus in Bandung, Indonesia

Background: Screening and treatment of latent TB infection (LTBI) and TB disease could reduce diabetes mellitus (DM)-associated TB. We aimed to describe the prevalence of LTBI and pulmonary TB among patients with DM in a TB-endemic setting.

Methods: Patients with DM attending a hospital and community centres in Bandung, Indonesia, underwent LTBI screening using interferon gamma release assay (IGRA). TB was investigated by sputum smear, culture and x-ray. TB contacts from a parallel study were age- and sex-matched to patients with DM to compare LTBI and TB disease prevalence.

Results: Of 682 patients with DM screened, 651 (95.5%) were eligible. Among 'TB disease-free' patients, LTBI prevalence was 38.9% (206/530; 95% CI 34.7-43.2). Patients with DM were less likely to be IGRA positive than TB contacts (38.6%, 54/140; 95% CI 30.5-46.6 vs 68.6%, 96/140; 95% CI 60.9-72.3: p<0.001); but had a higher disease prevalence (4.9%, 8/164; 95% CI 1.6-8.2 vs 1.2%, 2/164; 95% CI -0.5 to 2.9: p=0.054). Patients with DM in crowded households had increased risk of LTBI (AOR 1.71; 95% CI 1.19-2.45).

Conclusions: LTBI prevalence in patients with DM was lower than in household contacts, but patients with DM were more likely to have TB disease. Further studies should explore possible benefits of LTBI screening and preventive therapy in patients with DM in TB-endemic settings.