Imipenem/cilastatin as secondary therapy for infections in cancer patients.

Imipenem/cilastatin was used to treat 68 documented infections in patients who had failed to respond to other antibiotic regimens. The overall response rate was 68% and was higher among patients in whom the infecting organism could be identified (71% vs. 60%). The response rates were 73% in the 37 cases of septicaemia and 54% in the 13 cases of pneumonia. The response rate in Gram-negative bacillary infections was 69%, but was 50% for those caused by Pseudomonas aeruginosa. The response rate did not correlate with patients' neutrophil counts, but was higher if the neutrophil count increased during therapy than if it decreased (86% vs. 48%, P = 0.001). The drug was well tolerated but one patient developed seizures. Imipenem/cilastatin appears to be a useful antibiotic as single agent therapy for most infections in cancer patients.