Piperacillin/tazobactam in the treatment of hospitalized patients with urinary tract infections: an open non-comparative and multicentered trial

The aim of this multicentered, prospective and open study was to determine the clinical and bacteriological efficacy and safety of piperacillin/tazobactam (4g/500 mg IV tid) in the treatment of 79 adult patients with complicated urinary tract infections (UTI) requiring hospitalization. Forty-seven women and 32 men (mean age 54.2 years, and range 21-91) from 4 Argentinean and 6 Mexican hospitals were enrolled. Sixty-one clinically and bacteriologically evaluable patients were treated for a mean of 9.1 days (range 5-15). A favorable clinical response was seen in 83.6% and 80% at early and late assessment, respectively. Bacteriological eradication was achieved in 85.3% and 80% at early and late estimation, respectively. Escherichia coli was isolated in 33 cases, Klebsiella pneumoniae in 8, Enterococcus spp. in 7, Proteus mirabilis in 6, Pseudomonas aeruginosa in 3, Enterobacter spp. and Morganella morganii in 2. While 21% of all the clinical isolates were resistant to piperacillin, none of them was initially resistant to piperacillin/tazobactam. However, one female patient with a persistent UTI caused by E. coli developed resistance to piperacillin/tazobactam during treatment. A 64-year-old man with frontal meningioma developed purulent meningitis due to Enterobacter cloacae after neurosurgery. He was initially treated with ciprofloxacin, rifampin and amikacin and because of persistence of fever, he was moved to piperacillin/tazobactam. After 5 days of therapy, he developed coma secondary to intracranial hemorrhage and died. By then, the platelet count was normal (220,000/microliters), but the prothrombin time (19.5 seconds) and the partial thromboplastin time (63 seconds) were significantly prolonged. Our data suggest that piperacillin/tazobactam is a reliable therapy for complicated, non-complicated, community or hospital-acquired UTI.