Abstracts

Rationale: Thrombocytopenia as a side effect of levetiracetam has not been frequently reported. A case report of a patient who was not on any other thrombocytopenia inducing medications had severe thrombocytopenia that resolved with holding of levetiracetam will be presented. Methods: The patient is a 35 year old female with a past medical history of mental retardation and intractable epilepsy. Patient was admitted to the hospital for an increase frequency in seizures. Patient was noted to be having multiple episodes of head dropping, gaze aversion, and not responding. These episodes would last 2-3 seconds and could occur up to 4 episodes per minute. On admission patient was taking levetiracetam 2,000 mg bid, Topamax 200 mg bid, clonazepam 0.25 mg qhs, docusate sodium, folic acid, calcium, vitamin D, iron, lansoprazole, and acetaminophen. Patient’s past AED use included valproic acid and lamotrogine. In 2006, valproic acid was eventually weaned off secondary to thrombocytopenia. Patient was then placed on Topamax. Patient has a documented normal platelet that count was taken during a hospital admission in January 2008. At that time, patient’s admission platelet count was 266,000. Patient had been admitted for seizures. Patient was started on levetiracetam for the first time during the January admission. On discharge, patient’s platelet count was 197,000. Patient was discharged on levetiracetam 2,000 mg bid, Topamax 200 mg bid,a prednisone taper, pulmicort inhaler, Xopenex, albuterol inhaler, calcium, colace sodium, iron, folic acid, lansoprazole, Nystatin topical, and potassium. No blood work was drawn between end of January and March 2008. On admission to the hospital in March 2008, patient’s platelet count was 41,000. Hemoglobin was 11.5, and white blood cell count was 8.1. No new medications were added after discharge from the January hospital admission except for clonazepam. During patient’s March 2008 hospital course, the patient was treated for a presumed aspiration pneumonia with vancomycin and Zosyn. Because the thrombocytopenia was present on admission prior to the starting of any antibiotics or heparin products, a peripheral blood smear was also sent to further work up the thrombocytopenia. The platelets were normal in appearance. Hematology was then consulted for the thrombocytopenia. There was concern that medication effect was the cause for patient’s thrombocytopenia. Levetiracetam was gradually tapered off over a period of two to three days. During this taper, patient was placed on scheduled lorazepam and continued on her home dose of Topamax. Her platelet counts dropped down to 28,000 but then began to reverse a few days after the Keppra had been stopped. Results: Patient's platelet level increased from 28,000 to 250,000 after withdrawal of levetiracetam. Patient was not on any other medications which are known to have a side effect of thrombocytopenia. Conclusions: Levetiracetam can be associated with thrombocytopenia. A previous history of thrombocytopenia with valproic acid may suggest an underlying tendency towards thromboctyopenia induced by levetiracetam.