Rapid identification of bacteria and yeast: Summary of a National Committee for Clinical Laboratory Standards proposed guideline

Using colony morphology on selected agars, Gram-stain morphology, and a num ber of 1-step biochemical or enzymatic tests, skilled microbiologists can i dentify the species of the majority of isolates seen routinely in a clinica l laboratory. These results are often available more quickly than and are a s accurate as those derived from conventional methods. The National Committ ee for Clinical Laboratory Standards has produced a guideline that describe s tests that can be used to identify a number of aerobic gram-negative rods and gram-positive cocci, a number of commonly isolated anaerobes, and 3 sp ecies of yeast. An overview of the organisms included in the guideline, the tests that identify them, and the situations in which rapid testing is app ropriate is presented here.