The occurrence of extended-spectrum β-lactamase producing enterobacteria (ESBLE) has been
prospectively surveyed in a neurosurgical intensive care unit (ICU). Of the 47 patients
examined, 8 were identified as faecal carriers, and 2 of them developed a subsequent urinary
tract infection. ESBLE were also detected in the immediate environment of five colonized
and/or infected patients. All isolates were Klebsiella pneumoniae of a particular biotype which
exhibited a similar antibiotype and produced an SHV-4 type β-lactamase. However, plasmid
profiling and ribotyping revealed that strains isolated from seven patients of hall A were a
single epidemic clone, whereas strains isolated from the eighth patient of hall B were different.
Comparison between the characteristics of patients who carried an ESBLE during the
surveillance period, and control patients who did not, showed that a recent surgery, and the
length of ICU stay were significantly associated with the acquisition of ESBLE.