Primary autoimmune myelofibrosis, the development of which is not preceded by a well-defined autoimmune disease, has recently been defined as a distinct clinicopathologic syndrome. We report herein a case of a 68-year-old woman who was diagnosed with primary autoimmune myelofibrosis and present a review of the literature. The patient manifested peripheral pancytopenia, was positive for autoantibodies, and developed myelofibrosis with no preceding autoimmune or hematologic disorders. Her condition was dramatically improved after administration of prednisolone.
Aged ; Autoantibodies ; Autoimmune Diseases ; Female ; Humans ; Pancytopenia ; Prednisolone ; Primary Myelofibrosis*

Acquired hemophilia A (AHA) is a bleeding disorder caused by the development of an auto-antibody against endogenous factor VIII (FVIII). In this study, the epitope of the autoantibody was identified in a 67-year-old female patient with AHA. A prolonged activated partial thromboplastin time (77.4 s) that failed to correct in an incubation mixing test (68.2 s), a decreased FVIII activity, and a high FVIII inhibitor (14.6 Bethesda units/mL) were observed. Enzyme-linked immunosorbent assay demonstrated that the antibody belonged to the immunoglobulin G4 subclass. An immunoblotting assay revealed the light chain (A3/C1/C2 domain) of FVIII as the binding region of the antibody. The bleeding experienced by our patient resulted from the interference of FVIII binding to both FIX by anti-A3 antibodies and phospholipids and von Willebrand factor by anti-C2 antibodies. To the best of our knowledge, this is the first study in Korea characterizing an autoantibody in the context of AHA.
Antibodies ; Enzyme-Linked Immunosorbent Assay ; Factor VIII ; Female ; Hemophilia A ; Hemorrhage ; Humans ; Immunoblotting ; Immunoglobulins ; Korea ; Light ; Partial Thromboplastin Time ; Phospholipids ; von Willebrand Factor

Acquired hemophilia A (AHA) is a bleeding disorder caused by the development of an auto-antibody against endogenous factor VIII (FVIII). In this study, the epitope of the autoantibody was identified in a 67-year-old female patient with AHA. A prolonged activated partial thromboplastin time (77.4 s) that failed to correct in an incubation mixing test (68.2 s), a decreased FVIII activity, and a high FVIII inhibitor (14.6 Bethesda units/mL) were observed. Enzyme-linked immunosorbent assay demonstrated that the antibody belonged to the immunoglobulin G4 subclass. An immunoblotting assay revealed the light chain (A3/C1/C2 domain) of FVIII as the binding region of the antibody. The bleeding experienced by our patient resulted from the interference of FVIII binding to both FIX by anti-A3 antibodies and phospholipids and von Willebrand factor by anti-C2 antibodies. To the best of our knowledge, this is the first study in Korea characterizing an autoantibody in the context of AHA.
Antibodies ; Enzyme-Linked Immunosorbent Assay ; Factor VIII ; Female ; Hemophilia A ; Hemorrhage ; Humans ; Immunoblotting ; Immunoglobulins ; Korea ; Light ; Partial Thromboplastin Time ; Phospholipids ; von Willebrand Factor