Myelofibrosis is usually observed in association with hematologic malignancies or metastatic solid tumors, but it has rarely been reported in patients who suffer with autoimmune disorders. Autoimmune myelofibrosis is a distinct clinicopathologic entity and it can occur alone or in association with autoimmune disorders, and the final result is chronic peripheral cytopenia. Primary autoimmune myelofibrosis, in which the autoimmune myelofibrosis is not preceded by a well-defined autoimmune disease, has recently been defined as a distinct clinicopathologic syndrome. We report here on a case of an 18-year-old woman who was diagnosed with primary autoimmune myelofibrosis, and she manifested peripheral pancytopenia, positivity for autoantibodies and Grade III myelofibrosis without having any preceding autoimmune or hematologic disorders. (Korean J Hematol 2009;44:157-162.)

Keywords: Myelofibrosis, Primary, Autoimmune disorder