Red blood cell enzyme abnormalities in patients treated with chemotherapy

Sxiteen red blood cell enzyme activities and fetal haemoglobin level have been assayed in 60 patients treated for haematologic or nonhaematologic malignant diseases with various combinations of cytostatic drugs. Acquired enzyme deficiency was found in 20 patients. The most frequently decreased activities were those of G6PD (12 cases), PK (seven cases), PFK (six cases) and AK (three cases). In many patients decreased activity of some enzymes contrasted with increased activity of others such as ALD, TPI, G3PD, PGK, ENOL and 6PGD. The number of abnormalities seems to be related to the duration of the treatment. Incidence of enzyme deficiencies was similar in patients previously treated or not with radiotherapy. Enzyme abnormalities were correlated neither with haemoglobin level nor with reticulocyte count. They were very similar to those observed in primary acquired dyserythropoietic and preleukaemic states. Their prognostic value and mechanism are discussed.