Oxidative Stress and Inflammatory Markers in Infectious and Metabolic Diseases: A Comparative Study

Abstract

Background: Bacterial infections and type 2 diabetes mellitus (T2DM) independently dysregulate redox homeostasis and immune signalling; their co-occurrence may amplify these perturbations through shared transcriptional pathways. Aim: To quantify and compare oxidative stress and inflammatory biomarkers across healthy controls, patients with bacterial infection, patients with T2DM, and patients with concurrent bacterial infection and T2DM.

Methods: A cross-sectional comparative study enrolled 120 participants (30 per group) at a teaching hospital in Salah al-Din, Iraq (January–June 2024). Malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), erythrocyte sedimentation rate (ESR), and a full metabolic panel were measured. One-way ANOVA with Duncan’s post hoc test and Pearson correlation were applied using SPSS v.26. Results: Group 4 (concurrent disease) showed the highest MDA (5.28 ± 0.74 nmol/mL; p=0.004 vs controls) and the lowest SOD (1.87 ± 0.39 U/mL; p<0.001). MDA correlated positively with IL-6 (r=+0.63, p=0.008) and negatively with SOD (r=−0.54, p=0.041). CRP and IL-6 were severalfold elevated in Group 4 relative to all other groups (p<0.001). Conclusion: Co-existing bacterial infection and T2DM synergistically intensify oxidative and inflammatory burden, underscoring the need for integrated antioxidant monitoring in dually affected patients.