Background: Diabetes mellitus (DM) is believed to affect tuberculosis (TB) at multiple levels in disease control and treatment efficacy, but clinical and radiological presentation resulting from interaction of the two diseases is not known.
Methods: A cross-sectional study was conducted on data obtained from medical records of 438 patients confirmed with TB-DM comorbidity at the Third people’s hospital of Shenzhen from May 01, 2014, to April 30, 2019. Their CT images were reviewed, and patients were divided into subgroups according to lung cavitation: with and without cavities, and number of segments showing pulmonary infiltration: < 4 segment, 4– 8 segment, > 8 segment infiltrates. We then compared clinical parameters between these groups.
Results: The median age of the patients was 50.0 years (IQR 43.3– 56.0) and 86% (n=375) of them were male. Pulmonary cavities were found in 80.8% patients. About 42.7% and 27.2% patients were seen to have infiltration involving 4– 8 and > 8 lung segments, respectively. Patients presented with cavitation and infiltration involving a greater number of lung segments had significantly higher values of WBC, MONO%, GRA%, CRP, lower LYN% level and higher bacterial burden in sputum (P < 0.001). Higher HbA1c and FBG were only observed in patients with lung cavities (P < 0.001). There was no difference in positive ELISPOT.TB and PCT level between the groups regardless of presence or absence of lung cavity (P > 0.9 and P =0.1 respectively). Lower HGB, ALB and higher PCT were observed in patients with infiltration involving more lung segments.
Conclusion: Hyper-inflammation in peripheral blood was significantly associated with cavity and the number of lung lesions. Hyperglycemia was significantly associated with the development of lung cavity. Glycemic control and inflammation influenced radiographic manifestations in patients with TB-DM.
Keywords: diabetes mellitus, tuberculosis, lung cavity, lung infiltration, radiography