A 27-year-old man had been diagnosed as Evans syndrome (ITP+immune hemolytic anemia) at the age of 17 and treated with prednisolone, to which he became refractory. Splenectomy at the age of 24 failed to maintain normal platelet counts after a year. One and half years after the splenectomy, he was admitted because of ecchymoses, macroscopic hematuria and serious thrombocytopenia (3×10³/μl). Pulse therapy with methyl-prednisolone (m-PSL) (1.0g/day for 3 days) rapidly increased platelet counts to 105×10³/μl and improved hematuria. However, one week later, platelet counts again decreased to 3×10³/μl and the patient complained of serious colicky abdominal pains. Colonoscopy showed moderate colitis. The same m-PSL pulse therapy was again administrated, which increased platelet counts to 149×10³/μl but gave no effect on the abdominal pains. His blood levels of factor XIII antigen and activity were abnormally low (both 40% of normals). Based on a presumptive diagnosis of Schönlein-Henoch purpura, treatment with i. v. Factor XIII (Fibrogammin P, 6A/day) for 5 days dramatically improved abdominal pains. His platelet counts gradually decreased but he did not complain of an abdominal pain. Thereafter, the patient had another two attacks of colicky pains associated with abnormally decreased Factor XIII that were successfully treated with Fibrogammin.