Autoimmune acquired factor XIII deficiency due to anti-factor XIII/13 antibodies: A summary of 93 patients.

Autoimmune acquired factor XIII (F13) deficiency or autoimmune hemophilia-like disease (hemorrhaphilia) resulted from the generation of anti-F13 antibodies (AH13) is a severe bleeding disorder that occurs mainly in the elderly. Although rare, the number of patients diagnosed with AH13 has recently increased. To improve understanding of this disease, the author summarized 93 ever reported/diagnosed AH13 cases. About 50% of cases were idiopathic. In the remaining half of the patients, autoimmune diseases and malignancies were the most common underlying diseases. Intramuscular and subcutaneous bleeding were the most frequently reported symptoms. Hemorrhage was the cause of death in 13 patients. In 4 patients, the diagnosis was established after hemorrhagic death. Therefore, physicians/hematologists must raise the awareness of AH13 as a life-threatening disease. Most patients were treated with F13 concentrates to arrest bleeding and with prednisolone and cyclophosphamide to eradicate anti-F13 autoantibodies. AH13 cases tend to become chronic and intractable and require close follow-up over an extended period.