Erythrocyte uroporphyrinogen synthase activity as a possible diagnostic aid in the diagnosis of lymphoproliferative diseases

Patients with active lymphoproliferative diseases were shown to have high activity of erythrocyte uroporphyrinogen synthetase (URO‐S), the enzyme which converts porphobilinogen to uroporphyrinogen. In a few patients examined the lymphocyte URO‐S was markedly increased. No correlation was found between the high URO‐S activity and the degree of anemia, reticulocytosis, or the presence of hemolysis. Patients with epithelial malignancies and with some common viral diseases had normal erythrocyte URO‐S values. Three patients with nonalcoholic cirrhosis also had high erythrocyte URO‐S activities. The determination of erythrocyte and lymphocyte URO‐S activity may be of aid in the diagnosis of lymphoproliferative diseases. It may also indicate whether remission has been achieved and whether treatment should be continued or reinstituted. These preliminary observations justify the investigation of a larger patient and control material.