Colonial recognition, a "new" approach for rapid diagnostic enteric bacteriology.

The morphology, on MacConkey's agar, of colonies of the bacteria commonly found in enteric specimens is sufficiently characteristic and distinctive, when observed with transmitted oblique illumination and a low-power stereoscopic microscope, to enable identification at the generic (and occasionally the species) level with over 97% accuracy. Application of this technique resulted in great savings of time, manipulative steps, and media compared with the usual procedures of diagnostic enteric bacteriology, and there was an increase in sensitivity without sacrificing accuracy.