Extended Spectrum Beta Lactamase Testing

Answers from the Lab

Fecal microbiota transplantation, or stool transplantation, is a process wherein fecal matter is collected from a healthy person and transplanted into the gastrointestinal tract of a patient. It's a safe therapy that's used to treat severe or refractory Clostridium difficile infection.

Problems can occur, however, when donor stool is found to have harmful multi-drug resistant gram-negative extended spectrum beta lactamase (ESBL) bacteria that could jeopardize the success and safety of fecal microbiota transplants -- especially in patients who carry the bacteria in their gut without getting sick.

In this test specific episode of Mayo Clinic Laboratories’ “Answers From the Lab” podcast, clinical microbiologist and pathologist Audrey Schuetz, M.D., outlines how Mayo Clinic Laboratories’ new culture based ESBL testing panel screens for the colonization or carriage of ESBL bacteria.

“These bacteria are concerning for a few different reasons,” Dr. Schuetz says. “The first is that colonization with this bacterium has been associated with increased risk of infection in certain patient populations, especially those with hematologic malignancies. The second reason that we're concerned about this is that when a person has a multi-drug resistant bacterium, such as an ESBL and actually gets sick from this, that really limits the antibiotic treatment options for that patient because of the increased resistance. The third reason is more of a public health type of risk or concern in that the antibiotic resistance genes that are carried by these bacteria are easily passed from bacteria to bacteria.” Listen to learn more about how Mayo Clinic Laboratories’ new ESBL testing panel expands upon previous testing methods to improve outcomes for fecal microbiota transplant patients.

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Useful information

Screening for colonization of extended-spectrum beta-lactamase (ESBL)-producing organisms in stool. Screening fecal microbiota transplant donor feces for ESBL-producing organisms. This test is not intended for medicolegal use.

Specimen requirements

Patient preparation: Do not use barium or bismuth before specimen collection.

Supplies: C and S Vial (T058)

Specimen Type: Preserved Feces

Container/Tube: Cary-Blair or modified Cary-Blair transport system is required.

Commercially available transport system specific for recovery of enteric pathogens from fecal specimens (15 mL of nonnutritive transport medium containing phenol red as a pH indicator. Submit sample in original Cary Blair medium container (not an aliquot of Cary Blair medium).

Specimen Volume: Representative portion of feces; 1 gram or 5 mL

Collection Instructions:

  1. Collect fresh fecal specimen and place 1 gram or 5 mL in container with transport medium.
  2. Place feces in preservative within 2 hours of collection.
  3. Place vial in a sealed plastic bag.

Performance information

Analytic time: 4 days

Days performed: Monday through Sunday

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Barbara J. Toman

Barbara J. Toman is a Senior Communications Specialist at Mayo Clinic Laboratories. She is also the science writer for Mayo’s Neurosciences Update newsletter, which helps referring physicians to stay informed about Mayo’s treatment and research. Barbara has worked at Mayo Clinic since 2007. She enjoys international travel and cooking.