Effectiveness of Danazol as an adjunctive therapy in dogs with immune-mediated hemolytic anemia

Immune-mediated hemolytic anemia (IMHA) is autoimmune disease which is anemia caused by own immune system destroying the red blood cells (RBC). It can be diagnosed with spherocytosis, positive auto-agglutination of RBCs and direct antiglobulin test (DAT, Coomb's test). The treatment for IMHA are blood transfusion, immunosuppressive agents including glucocorticoids and other supportive therapies. Danazol is synthetic androgen that has effect of interfering the autoimmune reaction to RBCs. It can be used as an adjunctive agent in addition to glucocorticoids. To investigate its effectiveness, the medical records of 10 IMHA-diagnosed dogs were evaluated. All subjects were treated with blood transfusion, prednisolone, mycophenolate mofetil, and intravenous human immunoglobulin G. Additionally, 6 subjects were administered with danazol and 4 subjects were not. The results of initial blood examination and responses to the treatment for IMHA were compared between the groups. There were significant differences in the number of blood transfusions; once in group with danazol, twice in group without danazol, duration of recovery to normal hematocrit; 7.67±3.08 days in group with danazol, 22.00±5.66 days in group without danazol, and hospitalization; 5.17±0.75 days in group with danazol, 12.75±2.22 days in group without danazol. Therefore, danazol has potential effective on treating IMHA for rapid improvement.