Cytochemical detection of erythroblastic enzymes in acquired dyserythropoiesis

We have studied the amount and intracellular distribution of erythroblastic alkaline and acid phosphatase, nonspecific esterase, and N-acetyl-beta-glucosaminidase in 50 patients with acquired dyserythropoiesis. 19 morphologically normal bone marrow smears served as controls. Alkaline phosphatase was found in all controls (mean 9.4% of erythroblasts). The percentage of positive erythroblasts in pathological conditions varied greatly from absence to over 70%. Acid phosphatase and N-acetyl-beta-glucosaminidase were positive in pernicious anaemia and in acute erythremic myelosis. Nonspecific esterase was only detected in a case of erythremic myelosis. This case also showed a faint metachromasia with the dye azure A.