Systemic Immune-Inflammation Index and Platelet Parameters in Diabetic Kidney Disease

Diabetic kidney disease (DKD) is a frequent microvascular complication in individuals with type 2 diabetes mellitus (T2DM) and a major cause of chronic kidney failure worldwide. Chronic low-grade inflammation and platelet activation contribute significantly to renal microvascular damage. The purpose of this observational study is to evaluate whether routine blood test markers, specifically the Systemic Immune-Inflammation Index (SII), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and platelet indices (such as mean platelet volume \[MPV\] and platelet distribution width \[PDW\]), can serve as simple, accessible, and cost-effective biomarkers for identifying the presence and progression of diabetic kidney disease. Participants will include adult patients with type 2 diabetes categorized according to their urinary albumin-to-creatinine ratio (normoalbuminuria, microalbuminuria, and macroalbuminuria) as well as healthy control subjects. Complete blood counts, derived inflammatory indices, and renal parameters will be measured to assess their diagnostic accuracy for DKD.

Inclusion Criteria: * Adults aged 18 to 80 years, both males and females. * Confirmed clinical diagnosis and history of Type 2 Diabetes Mellitus (T2DM). * Healthy control subjects matched for age and sex (for the control cohort). Exclusion Criteria: * Type 1 diabetes mellitus. * Acute infections or clinical signs of active inflammation at the time of sampling. * Chronic inflammatory or autoimmune diseases (e.g., rheumatoid arthritis, systemic lupus erythematosus). * Known or recently diagnosed malignancies. * Chronic liver diseases, including cirrhosis or hepatitis. * Nephrotic syndrome or other known non-diabetic kidney diseases. * History of immunosuppressive therapy, systemic corticosteroids, or cytotoxic medications within the past 3 months prior to enrollment. * Pregnancy. * Significant cardiovascular complications.