Lithium therapy of canine cyclic hematopoiesis

Treatment of cyclic hematopoiesis in the grey collie dog with lithium carbonate eliminated the recurrent neutropenia and normalized the other blood cell counts. These findings suggest that human cyclic hematopoiesis may be successfully treated with lithium. The effects of lithium on the monocytes, platelets. and reticulocytes. as well as the neutrophils. suggest that lithium operates on basic regulatory mechanisms affecting the most primitive hematopoietic precursor cells. C YCLIC hematopoiesis in grey collie dogs is a disorder of hematopoietic stem cells in which there are cyclic fluctuations in the number of blood leukocytes, reticulocytes, and platelets. The blood cells cycle because of periodicity in the production of cells by the bone marrow, with a period length of 11-13 days. As a consequence of the cycling of the neutrophil counts, the dogs have recurrent infections and die prematurely. At least 50 % of the dogs die from infec-tions before they reach 3 wk of age.’ This canine disease is a remarkably close analog of human cycli