Randomised study of ticarcillin, cefamandole with or without tobramycin in febrile, neutropenic patients with solid tumors.

A prospective randomised study was conducted comparing the efficacy and toxicity of the antibiotics ticarcillin and cefamandole (TC) with or without tobramycin (TCT) in 100 febrile neutropenic patients with solid tumours undergoing conventional chemotherapy. In this study, neutropenia less than 100/microliter was noted in 31% of 106 evaluable infectious episodes and neutrophil counts less than 1,000/microliter persisted for a median 4 days. Infection was microbiologically documented in 42% of episodes (bacteremia 24%) with gram-negative organisms responsible for 63% of bacterial isolates. Overall, 65% of episodes responded to TC and 76% to TCT (p greater than 0.05). Patients with initial shock bacteremia, pulmonary infection, or gram-negative sepsis responded relatively poorly. Neutrophil nadir and pathogen susceptibility did not influence outcome. Antibiotic toxicity was minimal with no tobramycin-related nephrotoxicity. These results are broadly comparable to those observed with leukemic patients, but the relatively short duration of neutropenia in the solid-tumour patients appears to minimize the need for additional antibiotics provided there is adequate antimicrobial coverage with the initial choice of antibiotics.