Pulsed-field gel electrophoresis for differentiation of hospital isolates of Klebsiella pneumoniae.

Restriction enzyme analysis by pulsed-field gel electrophoresis (PFGE) was developed for differentiation of hospital isolates of Klebsiella pneumoniae. Restriction patterns generated by SpeI digestion of genomic DNAs of 36 isolates from patients in two major teaching hospitals established 34 PFGE types. All strains were typable by this technique and the SpeI restriction patterns were reproducible, stable and easy to interpret. As PFGE profiles generated were heterogenous, the incidence of cross-infection appeared to be low in each of the hospitals. The higher discriminatory power of PFGE when compared to conventional restriction endonuclease analysis (REA) suggests that this technique will be very useful for epidemiological investigations of nosocomial K. pneumoniae outbreaks.