The behaviour of LDH-3 in patients with malignant diseases during therapy with cytostatic drugs and prednisone, studied by LDH-isoenzyme electrophoresis on cellulose acetate

A modified method used for the quantitative estimation of LDH-isoenzymes in serum after electrophoresis on cellulose acetate is described. Total LDH-activity and isoenzyme distribution in serum samples of capillary blood are compared to those in samples collected by venipuncture. Total LDH-values and LDH-distributions both in 29 normal children and 14 children with malignant diseases are given. When studying the LDH-distribution in serum samples of children with malignant diseases a significantly decreased LDH-3 was found in many patients. LDH-4 and LDH-5 were also reduced. It was noted that these children all received therapy with prednisone. Possible explanations are discussed