Pseudo-Outbreak of Multidrug-ResistantMycobacterium tuberculosisAssociated With Presumed Laboratory Processing Contamination

Abstract

AbstractAn investigation prompted by six positive cultures for multidrug-resistantMycobacterium tuberculosisduring a 7-week period found that an unusual resistance pattern, temporal proximity of laboratory processing, and identical DNA fingerprints supported the theory of cross-contamination. Laboratory processing procedures included specimen batching and multi-use vials of buffer solution. Processing procedures were changed and no additional cases of suspected cross-contamination have been observed. '(Infect Control Hosp Epidemiol 2002;23:622).