Serum ribonuclease of normal persons and patients with renal impairment.

Serum ribonuclease of normal persons and of patients with renal impairment was determined with polycytidylic acid as substrate. There was a pronounced rise in the serum ribonuclease of patients with renal impairment. Average serum ribonuclease values of 25 normal persons and 25 patients with renal impairment, respectively were 110 and 2329 units per ml of serum. Serum ribonuclease, because of its unique specificity, stability and abnormal elevation in the sera of patients with renal failure, might serve as an additional indicator in the assessment of renal function.