Empiric therapy for infections in granulocytopenic cancer patients: continuous infusion of amikacin plus cephalothin.

A combination of amikacin sulfate given by continuous infusion (800 mg/sq m/24 hr) plus cephalothin sodium (2 g every four hours) was used as initial empiric therapy for the treatment of 65 evaluable febrile (greater than 38.5 degrees C) episodes in 54 granulcoytopenic (neutrophils, less than 1,000/microliter) adult cancer patients. Carbenicillin disodium (5 g every four hours) was substituted for cephalothin in patients with Pseudomonas infections and in patients in whom the initial regimen was unsuccessful. Thirty-two of the 38(84%) identifiable infections responded to therapy, including all of the eight septicemias and eight of 11 pneumonias. Three additional infections responded to the substitution of carbenicillin for cephalothin, for a total response rate of 92% (35/38). Nephrotoxicity occurred in five patients (7.1%), most commonly in patients over 60 years of age. Ototoxicity, highly correlated with a duration of greater than 19 days and a total dosage of greater than 25 g of amikacin sulfate, occurred in four patients (5.6%). Amikacin given by continuous infusion plus cephalothin is a safe and efficacious empiric therapy for infections in granulocytopenic cancer patients.