Listeria monocytogenes

Listeria monocytogenes is a Gram-positive, rod-shaped, facultative anaerobic and motile bacterium. It is able to form biofilm.

Listeria monocytogenes causes listeriosis, a principally foodborne infectious disease. Immunocompromised patients, pregnant women, and newborns are at risk of a severe course. Disease patterns include:

  • Gastroenteritis, enteritis

  • Endocarditis (inflammation of the inner lining of the heart)

  • Encephalitis (inflammation of the brain)

  • Meningitis (inflammation of the meninges)

  • Sepsis

Listeria monocytogenes is ubiquitous in the environment, particularly in the soil, on plants, and in wastewater. Listeria is also often found in spoiled silage.

Relevance of pathogen in transmission in endoscopy

  • Gastroenterology: Low

  • Pulmonology: Not relevant

  • Ear, nose, and throat: Not relevant

  • Urology: Not relevant

Relevance for endoscope surveillance

  • Low or moderate concern organism

Transmission route

Listeria monocytogenes is mainly transmitted orally through contaminated drinking water and food. Triggers are often poultry, meat, fish, and raw milk products, less frequently pre-made salads. Infection is also possible through very close contact with animals.

Listeria monocytogenes can also be spread and transmitted through water in healthcare facilities. The water used for final rinsing of endoscopes must therefore be microbiologically controlled.

Resistance to antibiotics

Listeria monocytogenes shows reduced susceptibility to cephalosporins.

Sources and further readings

  1. Gries O, Ly T: Infektologie – Kompendium humanpathogener Infektionskrankheiten und Erreger, Springer-Verlag Berlin Heidelberg 2019.

  2. Listeria, Centers for Disease Control and Preventions, Accessed on 07.01.2021.

  3. Listerien, European Food Safety Authority, Accessed on 07.01.2021.

  4. Listeriose, Robert Koch-Institut, Accessed on 07.01.2021.

  5. Listeriosis in an immunocompetent patient after diagnostic colonoscopy, Burch J, Samaniit K, Ikponmwosa E. Oxf Med Case Reports. 2019(9): omz089.

  6. Post-colonoscopic Listeria septicemia in ulcerative colitis during immunosuppressive therapy. Minami M, Hasegawa T, Ando T, Maeda O, Ohkura T, Ohta M, Goto H. Intern Med. 2007;46(24):2023–7.