New Guidelines for Enteric Cultures

Prepared by: Reo Paolo M. Uri

                      The practices of diagnosing GI Tract infections is really at a crossroads in the early twenty-first century. For dedades, clinical microbiology its have relied on fecal cultures completed with a battery of biochemical test to try to tease out the single pathogenic bacterium among the multitude of normal strains that reside in the intestinal tract. How many physicians feel that stool cultures are not necessary except in certain circumstances. Indeed, some studies show that 2% of routinely ordered stool cultures comeback positive for a significant pathogens. When we consider that some of these cultures can cost as much as S 1000 to process it is easy to see thier point.

                       It seems that the best guidelines to use is this: will the results of the culture change the therapy? Physicians generally agree that when fever is present, when there is blood in the stools or pain suggesting appendicitis, or if the patient gives a history that suggest possible exposure to E coli 0157: N7, stool cultures should be ordered. In other cases, physicians should use a variety of other indicators, both clinical and epidemiological, to diagnose diarrhea and other gastrointestinal disorders. Never technologies that can eventually make costly and slower culture technique obsolete.

Why do you think attempting to isolate and identify enteric pathogens from feces is so problematic and expensive?

Answer available at http://www.mhhe.com/talaro7