We discerned the immunological characteristics of diabetic kidney disease (DKD) and CKD due to other causes in this balanced cohort: B lymphocytes negatively correlate with alkaline phosphatase (R = −0.764, p < 0.05), parathyroid hormone (R = −0.929, p < 0.05), and ferritin (R = −0.893, p < 0.05). Here, PTH is linked to diabetic kidney disease.