Polyneuritis associated with azathioprine sensitivity reaction

Fraser et all in their original description of legionnaires' disease referred to three patients out of 182 with a WCC less than 2.0 x 109/1, two of whom died. Two other patients had WCCs of less than 6 0 x 109/1. During his acute illness our patient had pancytopenia with bone marrow depression. We can only speculate on the part played by legionnaires' disease in producing hypoplastic anaemia. A toxic effect on the marrow may explain the pancytopenia during the acute phase of the illness. Its recurrence within a few weeks of clinical recovery, however, was unexpected and difficult to explain. Marrow hypoplasia might have been present before the development of legionnaires' disease, although this seems unlikely in view of the return of an almost normal blood profile after clinical recovery. The role of co-trimoxazole in producing the hypoplastic anaemia is probably unimportant as the blood dyscrasias of this drug are quite distinct from that seen in our patient.3