Parathyroid hormone contributes to variations in blood morphology in diabetic and non diabetic patients treated with continuous ambulatory peritoneal dialysis.

The present study looked for variations in blood morphology between diabetic patients (group I, n = 7) and non diabetic patients (group II, n = 16) treated with continuous ambulatory peritoneal dialysis (CAPD). A subsequent trial sought to find a reason for discrepancies in the results between the two groups. The patients in both groups and similar ages, CAPD durations, and erythropoietin dosages. Nutrition, CAPD adequacy, serum iron and ferritin levels, total iron binding capacity (TIBC), transferrin saturation (TSAT), red blood cells (RBCs), mean corpuscular hemoglobin (MCH), mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC), hemoglobin (Hb), hematocrit (Hct), white blood cells (WBCs), total lymphocyte count (TLC), platelets (PLTs), and serum intact parathyroid hormone (PTH) were evaluated every three months. The mean result of each parameter was obtained in every patient as representative for the entire CAPD course. Means and standard deviations for all respective parameters were then calculated for the two groups and compared. In patients with diabetes as compared with patients without diabetes, significantly higher numbers of RBCs, WBCs, and PLTs were seen, as were higher values for Hb and Hct and a lower serum PTH concentration. Values for WBCs, PLTs, and MCH obtained in all patients (n = 23) were correlated with serum intact PTH (r = -0.520, p = 0.011; r = -0.422, p = 0.045; and r = -0.436, p = 0.037 respectively). When data obtained in the patients receiving erythropoietin were excluded and the correlation analysis was repeated for the 10 remaining patients, a correlation between serum PTH and RBCs was found (r = -0.685, p = 0.029). With comparable age, renal function, nutrition, erythropoietin dosage, iron indices, and CAPD adequacy, duration, and outcome, higher parameters of blood morphology in diabetic patients may be related to lower levels of serum intact PTH, indicating no or only mild secondary hyperparathyroidism. Patients with diabetes usually show smaller disturbances in PTH level than do non diabetic uremic patients on CAPD. Better peripheral morphology indices in the group with diabetes can be expected when other factors affecting hematologic status are similar.