Changes in Leukocyte Subpopulations with Decline in Glomerular Filtration Rate in Patients with Type 2 Diabetes

Recent studies suggested the role of white blood cells (WBCs) in the pathogenesis and complications of type 2 diabetes. Increased WBC counts predict mortality in patients with chronic kidney disease (CKD). In this study alterations in WBC subpopulations in diabetic patients with non-dialysis dependent CKD are investigated. This was a cross-sectional study on 376 participants, including 272 diabetic patients and 104 healthy controls. Total and differential WBC counts were compared among diabetics with CKD, diabetics without CKD and controls. Among patients with type 2 diabetes, there was no significant difference in total WBC count between those with and without CKD. Diabetic patients with CKD had higher neutrophil, monocyte and eosinophil and lower lymphocyte count compared with both diabetic patients without CKD and healthy controls. Except for monocytes, a significant association was observed between GFR and differential WBC counts, which persisted after adjustment for conventional diabetes risk factors (R2=0.272, P < 0.001 for regression model). Neutrophil/lymphocyte ratio was the best predictor of GFR in total study population (beta= -1.995 ± 0.45, P<0.001). Changes in WBC subpopulations are present even before significant alterations in total WBC count. Immune system dysfunction needs special consideration in diabetic patients with CKD.