Abstract: | Piperacillin plus amikacin was compared in a prospective randomized double-blind trial with our standard regimen of ticarcillin plus amikacin as empiric therapy of fever in patients with granulocytopenia. Profound persistent granulocytopenia (fewer than 100/μl polymorphonuclear leukocytes without a rise during therapy) was present in 60 percent of the patient trials in both treatment groups. Of 38 microbiologically and clinically documented infections treated with piperacillin plus amikacin, 22 (58 percent) showed improvement. Of 34 microbiologically and clinically documented infections treated with ticarcillin plus amikacin, 19 (56 percent) showed improvement. There was no difference in response between groups according to the site of infection or infecting pathogen. Toxicity was minimal, with an equivalent incidence of immediate reactions, nephrotoxicity and superinfection. Patients receiving ticarcillin plus amikacin became colonized with more resistant gram-negative bacilli (17) than did those receiving piperacillin plus amikacin (3). Despite the monosodium structure of piperacillin, hypokalemia was not reduced for patients who received piperacillin plus amikacin. Although piperacillin has a wider in vitro antibacterial spectrum than ticarcillin, the clinical efficacy and toxicity of the combination of piperacillin plus amikacin were similar to those of ticarcillin plus amikacin as empiric therapy. |