Over a 1-month period, there were five episodes of infusion-related Klebsiella pneumoniae bacteremia in four liver transplantation patients housed in the same ward. Investigation of nursing practices revealed that a common normal-saline bag, to which intravenous (iv) tubing and a stopcock were attached, was used to flush iv catheters. The iv tubing and stopcock were changed at sporadic intervals. Cultures of the normal saline and iv equipment yielded K. pneumoniae, which had the same susceptibility pattern as the patients' isolates. Isolates recovered during the outbreak from the patients and from the iv saline/equipment were of the same strain, as determined by pulsed-field electrophoresis of Xba I-digested genomic DNA. Termination of the practice of flushing iv catheters with a common normal-saline bag halted the outbreak.