The cytochemical beta-glucuronidase reaction in the differential diagnosis of acute leukaemias.

The value of the cytochemical beta-glucuronidase (beta-gluc.) reaction in the differential diagnosis of acute leukaemia was assessed in a series of 100 adult patients. A purely granular type of reaction was observed in 7 out of 8 cases of lymphoblastic leukaemia and in 2 of 11 cases of acute leukaemia of uncertain type. Such an exclusively granular reaction was never seen in other types of acute leukaemia. In most cases of myeloblastic, promyelocytic, myelomonocytic and monocytic leukaemia, a positive staining reaction was noted which was either diffuse or a combination of diffuse and finely granular. The cells of one patient with lymphoblastic leukaemia were negative for beta-gluc. A coarsely granular PAS reaction was noted in 5 cases of lymphoblastic leukaemia including the one with negative beta-glu, reaction. Our results show that the beta-gluc, reaction is of definite value in the diagnosis of lymphoblastic leukaemia, and that it is probably more sensitive than the PAS reaction. In monocytic or myelomonocytic leukaemia, the pattern and intensity of staining did not differ appreciably from that seen in myeloblastic leukemia.