Thrombocytosis related to piperacillin sodium and tazobactam sodium

A 67-year-old man with acute gangrenous appendicitis received intravenous infusion of ceftriaxone sodium (2 g once every 12 hours ) and ornidazole (0.5 g once every 12 hours) after emergency appendectomy. Three days later, antibiotics were changed to piperacillin sodium and tazobactam sodium (4.5 g once every 8 hours by intravenous infusion) based on the results of drug sensitivity. His platelet count (PLT) was 288×109/L before the operation, 308×109/L on the second day and 1 128×109/L on the 12th day of piperacillin sodium and tazobactam sodium treatment. The examination of bone marrow smear showed hyperplasia of bone marrow. Thrombocytosis was considered to be related to piperacillin sodium and tazobactam sodium. piperacillin sodium and tazobactam sodium was withdrawn and cefoperazone sulbactam sodium (3 g once every 12 hours by intravenous infusion) was given. After 9 days of treatment, his platelet count decreased to 360×109/L. Fifteen days later, his platelet count was 332×109/L. Key words: Piperacillin; Thrombocytosis