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Medical Author:

Steven Doerr, MD

Steven Doerr, MD

Steven Doerr, MD, is a U.S. board-certified Emergency Medicine Physician. Dr. Doerr received his undergraduate degree in Spanish from the University of Colorado at Boulder. He graduated with his Medical Degree from the University Of Colorado Health Sciences Center in Denver, Colorado in 1998 and completed his residency training in Emergency Medicine from Denver Health Medical Center in Denver, Colorado in 2002, where he also served as Chief Resident.

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Medical Editor:

John P. Cunha, DO, FACOEP

John P. Cunha, DO, FACOEP

John P. Cunha, DO, is a U.S. board-certified Emergency Medicine Physician. Dr. Cunha's educational background includes a BS in Biology from Rutgers, the State University of New Jersey, and a DO from the Kansas City University of Medicine and Biosciences in Kansas City, MO. He completed residency training in Emergency Medicine at Newark Beth Israel Medical Center in Newark, New Jersey.

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Diagnosing listeriosis promptly can be challenging, as it can initially present clinically similar to many other gastrointestinal infections. The patient's history can be critical, as it may provide information about exposure to certain food products known to harbor Listeria monocytogenes. Making a clinical diagnosis can be facilitated if there is a known outbreak of listeriosis.

The definitive diagnosis of infection with Listeria monocytogenes is confirmed by culturing and isolating the organism from blood, cerebrospinal fluid, amniotic fluid, or the placenta on specialized laboratory media. Isolating the specimen from stool samples is unreliable, as is serologic testing. Imaging studies, such as a CT scan or MRI of the brain, may be ordered to detect a brain abscess, for example. A spinal tap (lumbar puncture) to obtain cerebrospinal fluid may also be performed if there is suspicion of central nervous system infection.