Listeriosis
Alerts and Notices
Synopsis

Listeriosis is caused by the gram-positive bacillus Listeria monocytogenes. The organism infects farm and laboratory animals worldwide and is rarely directly transferred to humans by handling infected animals. Ingestion of contaminated milk, cheese, and poultry is the main source of human infection. While infection due to contaminated produce has been an uncommon occurrence, there has been an increase in produce-related illnesses in the past few years.
Although most adult infections appear to be minimally symptomatic, clinical presentations can range from mild to severe illness. Most symptomatic adult infections occur in immunocompromised patients and in those at the extremes of age, but infection in immunocompetent hosts does occur, particularly in farmers and veterinarians. Listeriosis is associated with increased susceptibility among pregnant individuals, who account for 1 in 4 reported cases in the United States. Infections during pregnancy can lead to stillbirth.
Severe infections present with meningitis, gastrointestinal symptoms and signs, or a glandular fever-like illness. Hematogenous spread and widespread dissemination is uncommon.
Cutaneous involvement outside of the neonatal period is rare and usually occurs from direct inoculation of the skin in farmers or veterinarians who are exposed to animal products of conception.
Pediatric patient considerations: As with adults, in children, infection and illness are more likely in the immunocompromised. Infection can occur by ingestion of contaminated or unpasteurized milk or ingestion of cheeses from unpasteurized milk.
The highest incidence of disease is in the neonatal period. See neonatal listeriosis for more information.
Although most adult infections appear to be minimally symptomatic, clinical presentations can range from mild to severe illness. Most symptomatic adult infections occur in immunocompromised patients and in those at the extremes of age, but infection in immunocompetent hosts does occur, particularly in farmers and veterinarians. Listeriosis is associated with increased susceptibility among pregnant individuals, who account for 1 in 4 reported cases in the United States. Infections during pregnancy can lead to stillbirth.
Severe infections present with meningitis, gastrointestinal symptoms and signs, or a glandular fever-like illness. Hematogenous spread and widespread dissemination is uncommon.
Cutaneous involvement outside of the neonatal period is rare and usually occurs from direct inoculation of the skin in farmers or veterinarians who are exposed to animal products of conception.
Pediatric patient considerations: As with adults, in children, infection and illness are more likely in the immunocompromised. Infection can occur by ingestion of contaminated or unpasteurized milk or ingestion of cheeses from unpasteurized milk.
The highest incidence of disease is in the neonatal period. See neonatal listeriosis for more information.
Codes
ICD10CM:
A32.9 – Listeriosis, unspecified
SNOMEDCT:
4241002 – Listeriosis
A32.9 – Listeriosis, unspecified
SNOMEDCT:
4241002 – Listeriosis
Look For
Subscription Required
Diagnostic Pearls
Subscription Required
Differential Diagnosis & Pitfalls
In pregnant patients:
Central nervous system (CNS) infection:
Central nervous system (CNS) infection:
- Other bacterial meningitis
- Fungal meningitis
- Mycobacterial meningitis (see atypical mycobacterial infection)
- Sepsis from other types of bacteremia
Best Tests
Subscription Required
Management Pearls
Subscription Required
Therapy
Subscription Required
Drug Reaction Data
Below is a list of drugs with literature evidence indicating an adverse association with this diagnosis. The list is continually updated through ongoing research and new medication approvals. Click on Citations to sort by number of citations or click on Medication to sort the medications alphabetically.
Subscription Required
References
Subscription Required
Last Reviewed:03/19/2023
Last Updated:04/30/2023
Last Updated:04/30/2023

Premium Feature
VisualDx Patient Handouts
Available in the Elite package
- Improve treatment compliance
- Reduce after-hours questions
- Increase patient engagement and satisfaction
- Written in clear, easy-to-understand language. No confusing jargon.
- Available in English and Spanish
- Print out or email directly to your patient
Upgrade Today