Yersinia enterocolitica

Background

Microbiology

• Gram-negative bacillus
• Serogroup O:3 and O:9 have a less effective siderophore that requires presence of iron overload or iron chelation to be invasive

Epidemiology

• Acquired from unpasteurized milk, undercooked meat (especially pork), contaminated water
  • Classic association with chitterlings

Risk Factors

• Iron overload
• Treatment with iron chelators, including deferoxamine
• Can be acquired from blood transfusion

Clinical Manifestations

• Incubation period of 1 to 14 days
• Classically causes gastroenteritis
  • Fever with blood diarrhea, vomiting
  • May cause terminal ileitis, which causes right lower quadrant pain mimicking appendicitis (pseudoappendicitis)
• Concurrent pharyngitis in 20%, can can be isolated from throat swabs
• Complications include bacteremia, with hematogenous dissemination with metastatic abscesses in the liver and spleen and mesenteric adenitis
• Can also cause pneumonia, septic arthritis, meningitis, panophthalmitis, cellulitis, empyema, osteomyelitis, and infective endocarditis or mycotic aneurysm
  • More common in immunodeficiency or iron overload
• Can lead to post-infectious reactive arthritis, erythema nodosum, and glomerulonephritis

Management

• Stop deferoxamine, if taking
• Unclear if antimicrobial treatment is beneficial unless severe
• Antibiotics are generally indicated in:
  • Severe disease
  • Extraintestinal disease, including meningitis, cellulitis, pneumonia, osteomyelitis, and endocarditis
  • High risk populations, including the elderly, people with diabetes, people with cirrhosis, and immunocompromised patients
• Options include ciprofloxacin, ceftriaxone, TMP-SMX, doxycycline, and aminoglycosides
  • Duration typically 7 to 14 days