Acute basophilic leukemia.

Acute basophilic leukemia was diagnosed in a 61-year-old black woman on the basis of 85 to 90 percent basophils in the peripheral blood as well as bone marrow and very high serum histamine level (more than 10,000 ng/ml). These complications occurred as a transformation from essential thrombocythemia. Accompanying this transformation, there was also cytogenetic change from 46XX karyotype to 46XX 2p+ in 66 to 90 percent of cells in the bone marrow. This may be the first reported occurrence of transformation of essential thrombocythemia into acute basophilic leukemia.