An outbreak of hospital-acquired Klebsiella pneumoniae bacteraemia, including strains producing extended-spectrum beta-lactamase

This study describes the clinical outcome of an outbreak of er;tended-spect rum p-lactamase producing Klebsiella pneumoniae (ESBL-KP) bacteraemia. Nine ty-two episodes of hospital-acquired K. pneumoniae bacteraemia mere studied , 49 ESBL-KP and 43 non-ESBL-KP, from May 1993 to June 1995. Of these, 44 ( 90%) episodes of ESBL-KP vs. 20 (46%) episodes of non-ESBL-KP occurred in i ntensive care unit (ICU) patients. The incidence of K. pneumoniae bacteraem ia (mainly due to ESBL-KP) increased in the ICU during the outbreak. A sign ificant association was found between intravascular catheter-related bacter aemia and isolation of ESBL-KP [27 (56%) in the ESBL-KP group vs. 13 (30%) in the non-ESBL-KP group; P=0.01]. The worst prognostic features were ident ified as age >65 years (P=0.02), septic shock (P<0.001) and secondary bacte raemia (P=0.04). High rates of resistance to <beta>-lactam/beta -lactamase inhibitors observed in our ESBL-KP isolates, as well as variable activity o f aminogly cosides, restricts the empirical use of these antibiotics. Carba penems should be the treatment of choice since they are uniformly active ag ainst these strains. Our study shows that ESBL-KP bacteraemia occurring in an epidemic ICU setting is mainly catheter-related. We did not find ESBL st rains to be associated with a significantly poor outcome. (C) 2001 The Hosp ital Infection Society.