Factors influencing erythrocyte sedimentation in patients with chronic renal failure.

Erythrocyte sedimentation was studied in stable patients with chronic renal failure free of complicating illnesses. The mean (+/- SD) Westergren erythrocyte sedimentation rate was 49 +/- 26 mm/hr in patients not receiving dialysis and 60 +/- 33 mm/hr in patients receiving hemodialysis. Both values are significantly higher than normal. Because anemia accelerates the Westergren determination, we restudied the patients with the zeta sedimentation ratio (ZSR), a method unaffected by hematocrit. In nine patients not receiving dialysis and 49 patients receiving hemodialysis, the ZSR was significantly higher than normal. The ZSR correlated positively with plasma fibrinogen concentration. Recombination experiments showed that the abnormal factor accelerating erythrocyte sedimentation was a constituent of plasma. Thus, erythrocyte sedimentation is accelerated in stable patients with chronic renal failure and a plasma factor, probably fibrinogen, is responsible. An elevated erythrocyte sedimentation rate in this population lacks diagnostic usefulness.