Pyoderma gangrenosum, defective neutrophil chemotaxis, and leukemia.

To the Editor.— In late 1972, Perry and Winkelmann1reported on the association of pyoderma gangrenosum with various forms of granulocytic leukemia in three patients. One of these patients had polycythemia vera and developed pyoderma gangrenosum at about the time leukemia became evident. Some time after this paper appeared, I encountered a patient with polycythemia vera of several years' duration and pyoderma gangrenosum of recent onset (Figure). On investigation, the patient had no evidence of ulcerative colitis, and his peripheral blood smear gave no evidence of leukemia. Because of the report of Perry and Winkelmann, a bone marrow aspiration was also performed to determine if there were any early signs of transformation into acute leukemia. At that time, however, no morphologic evidence of leukemia was apparent. Since I also wished to determine if the patient demonstrated evidence of impaired immunity or defects in neutrophil function, intradermal testing was done