Escherichia coli (E. coli) bacterial count in stool

Why This Test Is Done

Your healthcare provider may order this test if you have symptoms like diarrhea (especially with blood or mucus), abdominal pain, fever, or if you’ve recently traveled to areas with higher risk for foodborne illnesses. It’s also used to diagnose conditions like traveler’s diarrhea, food poisoning, or urinary tract infections that may have spread from the gut.

What to Expect Before the Test

No special preparation is needed, but you may be asked to collect a fresh stool sample in a sterile container. If you’re using a stool collection kit, follow the instructions carefully to ensure accuracy. Avoid using toilet paper or cleaning products that might alter the sample.

During the Test

The test involves analyzing a small portion of your stool under a microscope or using a culture method to detect and count *E. coli* bacteria. Results are typically reported as the number of bacteria present per gram of stool, though exact ranges can vary by lab.

What the Results Mean

A positive result means *E. coli* bacteria are present, which could indicate an infection. The presence of specific strains (like enterotoxigenic or enterohemorrhagic *E. coli*) may require further testing. A negative result means no detectable *E. coli* was found in this sample, but other causes of symptoms could still exist.