Microbiology Test

Stool Culture, Diarrheagenic E.coli

Dr. Nithin Jayan
Medically Reviewed by Dr. Nithin Jayan, MBBS, DNB
Last Updated on Apr 21, 2014
Email Print This Page Comment bookmark
Font : A-A+

Test : Stool Culture, Diarrheagenic E.coli

Indications : Ideally the stool culture test for E.coli must be ordered for all patients with bloody diarrhea. In case of outbreak, the test can even be done with watery stools which are not bloody. If EHEC is suspected, then the stool sample must be obtained as early as possible as it may be impossible to isolate enterohemorrhagic E.coli at a later stage.

E.coli is a part of the normal fecal flora and hence laboratories must be specifically instructed to detect pathogenic E.coli. Stool culture using sorbitol MacConkey medium is the standard diagnostic method.

Stool samples can be obtained by inserting a preservative-dipped cotton swab into the rectal region and by rotating it gently. It is then placed in a sterile container and transported to the laboratory as quickly as possible. The sample is streaked on to culture plates containing specific media that facilitates the growth of E.coli such as sorbitol MacConkey medium.

Physiology : This stool culture test is carried out to detect the presence of Diarrheagenic E.coli.

Most of the time E.coli exists as normal parasites in human intestines. Some strains, however, are pathogenic and cause severe illnesses. It is a common cause of food poisoning and travelers’ diarrhea.

The following are the four major categories of Diarrheagenic E.coli -

Enterotoxigenic (ETEC) - Travelers’ diarrhea and infant diarrhea in less developed countries

Enteropathogenic (EPEC) - Infant diarrhea

Enterohemorrhagic (EHEC) - Hemorrhagic colitis, Hemolytic uremic syndrome, Thrombotic thrombocytopenia purpura.

Enteroinvasive (EIEC) - Dysentery

Normal Range : Normal colinc flora

Interpretation : Normal

Negative - Only normal flora present

Abnormal

Positive - Pathogenic E.coli are seen in the culture indicating enteritis due to these pathogens.

Sample : Rectal swab, fresh stool

Test Method : culture in macconkey agar.

Related Tests : Methylene blue stain, Stool culture



Revise This Test    Add New Test

Post a Comment

Comments should be on the topic and should not be abusive. The editorial team reserves the right to review and moderate the comments posted on the site.
Notify me when reply is posted
I agree to the terms and conditions

Lab Test A - Z

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Lab Test Search

Premium Membership Benefits

Medindia Newsletters

Subscribe to our Free Newsletters!

Terms & Conditions and Privacy Policy.

Stay Connected

  • Available on the Android Market
  • Available on the App Store