Following an outbreak of carbapenem resistant Klebsiella pneumoniae (CRKP) bacteremia among inpatients in the Hemato-oncology and BMT unit, we studied the course of this infection in patients undergoing intensive chemotherapy and SCT. In addition, we conducted a pilot study aimed to eradicate CRKP colonization in the gastrointestinal tract, using oral gentamicin. Adult patients admitted to the BMT unit, identified as CRKP carriers on surveillance rectal cultures, were included in the study. Oral gentamicin at a dose of 80 mg q.i.d. was administered to all identified carriers until eradication. Among 15 colonized patients included in the study, the eradication rate achieved was 66% (10/15); discontinuation of persistent bacteremia occurred in 62.5% (5/8) and nosocomial spread of CRKP carrier state ceased. Administration of intensive chemotherapy and SCT is feasible, although associated with increased risk. Hematological patients in need of intensive chemotherapy/SCT should not be denied the required treatment on the basis of being CRKP carriers. Oral gentamicin treatment for eradication of CRKP from the gastrointestinal reservoir could serve as additional tool in the combat against the nosocomial spread and severe infections caused by this difficult-to-treat organism.