Use of Immunosuppression, Romiplostim, and Splenectomy to Achieve Remission in a British Shorthair Cat With Primary Immune-Mediated Thrombocytopenia.

A 2-year-old female spayed British Shorthair cat was diagnosed with immune-mediated thrombocytopenia (ITP) after presenting with a 3-week history of gastrointestinal bleeding and anemia. Treatment with an immunosuppressive dose of glucocorticoids was initiated, but relapse occurred within 3 weeks. Because of persistent thrombocytopenia and recurrence of clinical signs of active bleeding, despite further treatment with chlorambucil, romiplostim, and subsequently splenectomy and mycophenolate mofetil was used to successfully treat the cat for 6 months. This case describes the first known use of romiplostim for the treatment of ITP in a cat and demonstrates that although the efficacy of sustained romiplostim use might be variable, it might be effective in treating life-threatening thrombocytopenia while alternative treatments are pursued.