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
