Empiric Therapy with Carbenicillin and Gentamicin for Febrile Patients with Cancer and Granulocytopenia

Seventy-five acutely ill, febrile patients with cancer and granulocytopenia were treated empirically with a combination of carbenicillin and gentamicin for presumed bacterial infection. Cultures taken before the initiation of antibiotics subsequently documented the presence of infection in 48 of these patients, of whom 21 were shown to have Pseudomonas aeruginosa infections. Fourteen of these patients with pseudomonas infections had complete improvement, three improved temporarily but later died of infection, two had no improvement, and two could not be evaluated. This antibiotic combination was less promising for the infections caused by other gram-negative bacteria, especially klebsiella. Superinfection occurred in eight patients. Combination carbenicillin and gentamicin is of value as initial antibiotic therapy for suspected Ps. aeruginosa infection in granulocytopenic patients with cancer but only after careful examination and extensive culturing.