The role of diabetes on the clinical manifestations of pulmonary tuberculosis

Objective Diabetes is associated with pulmonary tuberculosis (TB), possibly due to impaired immunity, and diabetes may exacerbate the clinical manifestations of TB. Our aim was to assess the role of diabetes in the clinical manifestations of TB. Methods We studied 1250 patients with pulmonary TB in an urban population in a cross‐sectional study in Tanzania. All participants were tested for diabetes and HIV co‐infection, and TB culture intensity was assessed. Levels of white blood cells, haemoglobin, acute phase reactants, CD4 count and HIV viral load were measured, and a qualitative morbidity questionnaire was used to identify the prevalence of disease‐related symptoms. Results Tuberculosis patients with diabetes had a higher neutrophil count (B 0.5 × 10⁹ cells/l, 95% CI 0.2; 0.9, P = 0.001) than non‐diabetic TB patients. Serum C‐reactive protein (B 18.8 mg/l, CI 95% 8.2; 29.4, P = 0.001) and alpha‐1‐acid glycoprotein (B 0.2 g/l, CI 95% 0.03; 0.3, P = 0.02) were similarly higher in patients with diabetes. Diabetes did not affect culture intensity or HIV status, but self‐reported fever was three times higher among participants with diabetes than in those without diabetes (OR 2.9, CI 95% 1.5; 5.7, P = 0.002). Conclusion Diabetes is associated with small changes in the manifestations of TB, but may have little clinical significance.