Autoantibodies against coagulation factor XIII in autoimmune factor XIII deficiency

Key Points

• To investigate the characteristics and implications of autoantibodies in autoimmune factor XIII deficiency.
• Identified 83 cases of autoimmune factor XIII deficiency in Japan since 2009.
• Classified autoantibodies into three types: Aa, Ab, and B based on their binding effects.
• Monitored changes in FXIII-A levels and the presence of antibodies over time.
• Aa type autoantibodies often lead to significantly reduced plasma FXIII-A levels.
• The presence of clearance-promoting antibodies was suggested in many cases.
• The timing of inhibitor disappearance and recovery of FXIII-A antigen often differed significantly.