A puerperal patient with agranulocytosis during tazobactam / piperacillin administration : A case report

Tazobactam / piperacillin (TAZ / PIPC) is an injectable combination drug consisting of a broad-spectrum penicillin and a β-lactamase inhibitor. This antimicrobial has a wide spectrum of efficacy against both Gram-positive bacteria and anaerobes. Adverse events usually present as diarrhea or liver dysfunction ; agranulocytosis has not been reported in Japanese patients with puerperal disorders. However, we report a 32-year-old Japanese woman who received TAZ / PIPC to treat an intraperitoneal infection that developed after complications related to transvaginal delivery. Within 14 days of beginning TAZ / PIPC therapy, the patient developed agranulocytosis, indicated by a white blood cell count of 1900 cells / µL and a neutrophil count of 475 cells / µL. We discontinued TAZ / PIPC at this point and changed the antimicrobial to meropenem. Seven days later, her white blood cell count increased to 3700 cells / µL (neutrophil count : 1684 cells / µL), and the intraperitoneal infection resolved. Patients receiving TAZ / PIPC should be monitored periodically for agranulocytosis as well as for diarrhea and liver dysfunction. J. Med. Invest. 68 : 368-371, August, 2021.