Romiplostim-related myelofibrosis in refractory primary immune thrombocytopenia: A Case report

Primary immune thrombocytopenia (ITP) is an immune-mediated disease that is defined as increased platelet destruction and impaired platelet production. Treatment is recommended for highly selected patients, the standard regimen includes glucocorticoid, intravenous immunoglobulin (IVIG). The recombinant thrombopoietin (TPO) receptor agonists, romiplostim, stimulate platelet production and have approved for glucocorticoid or IVIG, splenectomy-refractory chronic ITP patients.

A patient has been diagnosed with ITP, reftractory to steroid, IVIG, splenectomy, danazol, and cyclosporine. The patient received romiplostim to normalize his platelet count, however, over the course of the following year, his platelet counts progressively decreased despite increasing the romiplostim dosing.

A peripheral blood smear showed a severe leukoerythroblastic reaction and bone marrow biopsy demonstrated myelofibrosis due to romiplostim.

Since this diagnosis, romiplostim was discontinued for a while, after 3 months, romiplostim was re-administered to improve thrombocytopenia. His platelet count recovered to 70,000/mm after the administration of romiplostim at 2 μg/kg, and he did not experience complications for 6 months.

This report represents the first evidence of romiplostim-induced myelofibrosis, which was associated with increased levels of bone marrow reticulin and Masson trichrome staining.