Bacillus welchii as an agent in experimental anemia.

Abstract

By one or two intramuscular injections of rabbits with 0.5 to 1.0 cc. of whole culture of B. welchii it has been possible to produce a severe toxic anemia within five days. The blood picture has been that of a secondary anemia, in which the hemoglobin is reduced to 50 or even to 25 per cent of the normal, and the red blood corpuscles are reduced to 2,380,000 or even 840,000 per cu. mm., accompanied by a leucocytosis of 20,000 to 43,000 per cu. mm. Marked anisocytosis and poikilocytosis were observed at the height of the disturbance. Erythroblasts were observed, from 642 to 4,352 per cu. mm.; among them normoblasts, microblasts and macroblasts. Monocytes or clasmatocytes in the peripheral blood containing ingested red blood cells were present, numbering from 186 to 868 per cu. mm. The maximum loss of weight varied from 9 to 23.9 per cent. Histologic examination of the spleen of these rabbits showed a marked increase of erythrophagocytosis. Repeated intramuscular injections of 0.1 to 1.0 cc. of whole culture or of toxic filtrates of B. welchii into rabbits produced chronic intoxication with accompanying secondary anemia. Those animals treated with whole culture showed decrease in hemoglobin from 56 to 53 per cent of the normal in periods varying from 5 to 19 days. A leucocytosis of 13,000 to 29,400 was present. Anisocytosis, poikilocytosis and polychromatophilia were marked from the third to the fifteenth day of treatment and remained to a slight degree as long as the injections were continued, covering in most instances, a period of 25 to 40 days. Nucleated red cells were present in numbers varying from 148 to 270 per cu. mm. Erythrophagocytosis in the blood stream was not observed.