MULTICENTER TYPING COMPARISON OF SPORADIC AND OUTBREAK CLOSTRIDIUM-DIFFICILE ISOLATES FROM GEOGRAPHICALLY DIVERSE HOSPITALS

In a collaborative study by three laboratories, arbitrarily primed pol ymerase chain reaction (AP-PCR), HindIII restriction enzyme analysis ( REA), and pulsed-field gel electrophoresis (PFGE) using SmaI were comp ared for typing of Clostridium difficile. The study included 30 isolat es from nosocomial outbreaks in six geographically disparate hospitals and 15 isolates from sporadic cases of C., difficile diarrhea, REA di stinguished a total of 23 types representing 10 groups; AP-PCR perform ed at Deaconess Hospital resolved 19 types; AP-PCR performed at the Ce nters for Disease Control resolved 15 types, Thirty isolates exhibited degradation of larger sized fragments during processing and therefore were nontypeable by PFGE; among the remaining 15 isolates, PFGE resol ved 11 types. Outbreak isolates in five different hospitals represente d REA group J and constituted a single AP-PCR strain, In summary, noso comial outbreaks of C., difficile diarrhea in five hospitals were asso ciated with a single genetic lineage as resolved by multiple strain ty ping systems.