Screening tests for the presumptive identification of Corynebacterium diphtheriae in a diagnostic laboratory

The article by Pennie et al. and the letters by Wong et al. and Efstratiou and George illustrate problems associated with the misidentification of isolates of toxigenic Corynebacterium diphtheriae.These articles stress the importance of maintaining appropriate experience with this group of organisms in order to avoid future problems and urge continued vigilance by clinical laboratorians and use of appropriate tests to ensure that these important pathogens are accurately identified.