Enterovirulent E. coli (EEC)

  • Medical Author:
    Charles Patrick Davis, MD, PhD

    Dr. Charles "Pat" Davis, MD, PhD, is a board certified Emergency Medicine doctor who currently practices as a consultant and staff member for hospitals. He has a PhD in Microbiology (UT at Austin), and the MD (Univ. Texas Medical Branch, Galveston). He is a Clinical Professor (retired) in the Division of Emergency Medicine, UT Health Science Center at San Antonio, and has been the Chief of Emergency Medicine at UT Medical Branch and at UTHSCSA with over 250 publications.

  • Medical Editor: Jay W. Marks, MD
    Jay W. Marks, MD

    Jay W. Marks, MD

    Jay W. Marks, MD, is a board-certified internist and gastroenterologist. He graduated from Yale University School of Medicine and trained in internal medicine and gastroenterology at UCLA/Cedars-Sinai Medical Center in Los Angeles.

How are enterovirulent E. coli infections diagnosed?

The diagnosis is usually made by an accurate history, physical exam, and analysis of a fecal sample from the patient. A presumptive diagnosis is often made if the patient's history indicates an association with persons, foods, or fluids known to contain E. coli 0157:H7 or other EEC group bacteria; such a presumptive diagnosis is often made during outbreaks of the disease. However, in patients who require hospitalization, a definitive diagnosis is usually sought.

A definitive diagnosis is often made by culture of E. coli strains from a fecal specimens on selective media (sorbitol-MacConkey agar) when colonies react with antiserum directed against specific "O" antigen strains. The selective medium and antiserum help distinguish E. coli serovars from other similar pathogens such as Listeria, Salmonella and Shigella. Other tests include PCR (polymerase chain reaction) and immunofluorescence tests to help identify the E. coli serovar.

The CDC has recommended (2009) that all patients being evaluated for community-acquired diarrhea have their stool samples analyzed by immunologic test systems that detect all types of Shiga toxins as this test will likely detect almost all bacteria that produce Shiga toxins, especially E. coli 0157:H7 strains. The CDC suggests that this test is even better than bacterial culture techniques, but recommends that both culture and immunologic tests should be done at the same time. This is suggested since E. coli that produces Shiga or Shiga-like toxins usually have the potential to be very damaging to the infected person(s).

In 2013, the FDA approved a new test that can detect and differentiate between eleven pathogens (bacterial and viral) that include Escherichia coli O157, enterotoxigenic E coli LT/ST, Salmonella,Shigella, and Shiga-like toxin producing E coli stx 1/stx 2) by detecting their nucleic acids. These types of tests will help health care professionals identify and differentiate the many causes of gastroenteritis.

Medically Reviewed by a Doctor on 5/16/2016

Subscribe to MedicineNet's Newsletters

Get the latest health and medical information delivered direct to your inbox!

By clicking Submit, I agree to the MedicineNet's Terms & Conditions & Privacy Policy and understand that I may opt out of MedicineNet's subscriptions at any time.

Health Solutions From Our Sponsors