Management of autoimmune factor XIII deficiency in a frail, elderly patient.

Autoimmune factor XIII/13 deficiency (aFXIII deficiency) is a rare hemorrhagic disorder, for which typical guideline-directed treatment is aggressive immunosuppressive therapy. Approximately 20% of patients are over 80 years old; however, and optimum management of such patients has not reached consensus. Our elderly patient had massive intramuscular hematoma, and aFXIII deficiency was diagnosed. The patient opted against aggressive immunosuppressive therapy, so he was managed with conservative treatment only. Thorough survey of other correctable causes of bleeding and anemia is also required in similar cases. Our patient's serotonin-norepinephrine reuptake inhibitor use and multivitamin deficiency (vitamin C, B 12 and folic acid) were revealed to be aggravating factors. Fall prevention and muscular stress prevention are also important in elderly patients. Our patient had two relapses of bleeding within 6 months, which were improved spontaneously by bed rest without factor XIII replacement therapy or blood transfusion. Conservative management may be preferred for frail and elderly patients with aFXIII deficiency when they opt against standard therapy.