Interference of Type 2 Diabetes Mellitus in the Early Diagnosis of Sepsis: Clinical Challenges and Biomarkers

Abstract

Background/Objectives: Type 2 diabetes mellitus (T2DM) substantially increases the risk of infection and sepsis while modifying host immune responses, clinical presenta-tion, and biomarker performance. This review summarizes the pathophysiological mechanisms by which T2DM interferes with the early recognition of sepsis and criti-cally evaluates the performance of conventional and emerging biomarkers in this spe-cific population. Methods: A narrative review of the literature was conducted using PubMed, Scopus, and Web of Science. Original studies, systematic reviews, me-ta-analyses, international guidelines, and landmark publications addressing the inter-action between T2DM, sepsis, immune dysfunction, and sepsis biomarkers were criti-cally analyzed. Results: Chronic hyperglycemia induces immune dysregulation, endo-thelial dysfunction, and persistent low-grade inflammation, resulting in atypical infec-tion presentations and reduced sensitivity of conventional clinical assessment tools. Baseline elevations and altered kinetics of C-reactive protein, procalcitonin, interleu-kin-6, and other inflammatory biomarkers may reduce their diagnostic specificity. Lactate retains prognostic value but should be interpreted cautiously in patients with diabetic ketoacidosis or other metabolic disturbances. Emerging biomarkers, including presepsin, pro-adrenomedullin, soluble urokinase plasminogen activator receptor, cell-free DNA, and 16S rRNA, show promising diagnostic potential, although evidence in diabetic populations remains limited. Conclusions: T2DM represents a distinct clin-ical phenotype in sepsis that requires individualized interpretation of biomarkers. Multimarker strategies integrating clinical, metabolic, and laboratory data may im-prove early sepsis recognition, but prospective validation studies in diabetic popula-tions are still needed.