BACKGROUND: Growing evidence suggests that chronic inflammation caused by tuberculosis (TB) may increase the incidence of diabetes. However, the relationship between post-TB pulmonary abnormalities and diabetes has not been well characterized.
METHODS: We analyzed data from a cross-sectional study in KwaZulu-Natal, South Africa, of people 15 years and older who underwent chest X-ray and diabetes screening with hemoglobin A1c testing. The analytic sample was restricted to persons with prior TB, defined by either (1) a self-reported history of TB treatment, (2) radiologist-confirmed prior TB on chest radiography, and (3) a negative sputum culture and GeneXpert. Chest X-rays of all participants were evaluated by the study radiologist to determine the presence of TB lung abnormalities. To assess the relationships between our outcome of interest, prevalent diabetes (HBA1c ≥6.5%), and our exposure of interest, chest X-ray abnormalities, we fitted logistic regression models adjusted for potential clinical and demographic confounders. In secondary analyses, we used the computer-aided detection system CAD4TB, which scores X-rays from 10 to 100 for detection of TB disease, as our exposure interest, and repeated analyses with a comparator group that had no history of TB disease.
RESULTS: In the analytic cohort of people with prior TB (n = 3,276), approximately two-thirds (64.9%) were women, and the average age was 50.8 years (SD 17.4). The prevalence of diabetes was 10.9%, and 53.0% of people were living with HIV. In univariate analyses, there was no association between diabetes prevalence and radiologist chest X-ray abnormalities (OR 1.23, 95%CI 0.95-1.58). In multivariate analyses, the presence of pulmonary abnormalities was associated with an 29% reduction in the odds of prevalent diabetes (aOR 0.71, 95%CI 0.53-0.97, p = 0.030). A similar inverse relationship was observed for diabetes with each 10-unit increase in the CAD4TB chest X-ray scores among people with prior TB (aOR 0.92, 95%CI 0.87-0.97; p = 0.002), but this relationship was less pronounced in the no TB comparator group (aOR 0.96, 95%CI 0.94-0.99).
CONCLUSIONS: Among people with prior TB, pulmonary abnormalities on digital chest X-ray are inversely associated with prevalent diabetes. The severity of radiographic post-TB lung disease does not appear to be a determinant of diabetes in this South African population.

This study provides a brief view of chronic pulmonary aspergillosis (CPA) in the post-tuberculosis treatment community in Vietnam, a high burden tuberculosis (TB) country. In three months in late 2019, 70 post-TB patients managed at Vietnam National Lung Hospital were enrolled. Of these, 38 (54.3%) had CPA. The male/female ratio was 3/1 (28 males and ten females). CPA patients had a mean age of 59 ± 2.3 years (95%CI 54.4-63.6). The mean Body mass index (BMI) was 19.0 ± 0.5 (18.0-20.0) and 16 of 38 (42.1%) patients had concurrent diseases, the most common of which were chronic obstructive pulmonary disease (COPD) and diabetes. Twenty-six patients (68.4%) developed hemoptysis, 21 (55.3%) breathlessness, and weight loss was seen in 30 (78.9%). Anaemia was seen in 15 (39.5%) and 27 of 38 (71.1%) patients had an elevated C-reactive protein (CRP). The most common radiological findings were multiple cavities (52.6%) and pleural thickening (42.7%), followed by aspergilloma (29.0%) and non-specific infiltrates. There were five of 38 patients (13.2%) with a cavity containing a fungal ball on the chest X-ray, but when the high resolution computed tomography (HRCT) was examined, the number of patients with fungal balls rose to 11 (28.9%). Overall, 34 of 38 (89.5%) cases had an elevated Aspergillus IgG with an optical density ≥ 1, and in 2 cases, it was 0.9-1.0 (5%), borderline positive. In nine patients (23.7%) Aspergillus fumigatus was cultured from sputum. CPA is an under-recognised problem in Vietnam and other high burden TB countries, requiring a different diagnostic approach and treatment and careful management. HRCT and Aspergillus IgG serum test are recommended as initial diagnostic tools for CPA diagnosis.