Platelet count and thrombopoietic activity in patients with chronic renal failure.

The frequency of thrombocytopenia in patients with chronic renal failure (CRF) is controversial. This study was undertaken to investigate the platelet count in 55 patients with end-stage renal disease on maintenance hemodialysis and in 19 patients with CRF before hemodialysis had begun. In both groups platelet counts were similar and significantly reduced, 175,000 +/- 6,500 and 181,000 +/- 10,800 compared to 253,000 +/- 3,700/mm3 in the control (p less than 0.0001). 31% of hemodialysis patients had thrombocytopenia (platelet count less than 150,000/mm3). The megakaryocyte number in their bone marrow aspirate was not reduced. Primary renal disease, androgen treatment or parathyroidectomy did not affect the platelet count. Thrombopoietic activity using 75Se-selenomethionine incorporation into platelets measured in 7 thrombocytopenic patients was found to be reduced, 6.77 +/- 0.29 vs. 9.06 +/- 0.27 (X 10(-2)%: p less than 0.001). This study shows that the platelet count is reduced and mild thrombocytopenia is frequent in patients with CRF. A possible cause for the platelet count reduction is insufficient thrombopoietic activity.