The interplay between type 2 diabetes mellitus and sepsis: a scoping review

Type 2 diabetes mellitus (T2DM) influence sepsis onset and progression. This scoping review mapped 33 studies from PubMed and Scopus up to June 2025 that examined immune, genetic, metabolic, prognostic, clinical, or treatment-related outcomes in patients with T2DM and sepsis. Sepsis patients with T2DM were prone to infections. Immune dysregulation in diabetic sepsis involved sustained pro-inflammatory cytokine release, impaired anti-inflammatory responses and altered immune cell profiles. Multi-organ dysfunction was more severe in T2DM. Monocyte chemoattractant protein-1 polymorphisms increased sepsis susceptibility and amplified inflammation. Poor glycaemic control, advanced diabetes, and comorbidities worsened sepsis outcomes and prolonged hospitalisation. Mortality findings in diabetic sepsis were inconsistent. Insulin influenced sepsis outcomes by C-peptide modulation. Metformin, sodium-glucose co-transporter-2 inhibitors, dipeptidyl peptidase-4 inhibitors, and statins exhibited immunomodulatory effects. Granulocyte-macrophage colony-stimulating factor and ulinastatin restored immune function and suppressed inflammation. Larger multi-ethnic studies are warranted to define optimal glycaemic targets, uncover immune-metabolic interactions, identify biomarkers, and optimise T2DM management in sepsis.