Yersinia pseudotuberculosis causes disease which presents clinically as an acute appendicitis, but on investigation the appendix is normal. This condition may only be discriminated from acute appendicitis at time of operation.
The actual problem is an acute mesenteric lymphadenitis or terminal ileitis.
Occasionally, this organism causes erythema nodosum and a polyarthritis; very rarely septicaemia.
Summary: Yersinia pseudotubercolosis and Yersinia entercolitica
Cause:
- Yersinia enterocolitica and Yersinia pseudotuberculosis
Reservoir:
- Asymptomatic carriage in the gastrointestinal tract of wild and domesticated animals and birds, particularly pigs for Y. enterocolitica
Epidemiology:
- most commonly seen in those less than 15 years of age
- seasonal variation occurs - Y. pseudotuberculosis is more common in winter and Y. enterocolitica is more common from June to November
Transmission:
- Faecal-oral:
- consumption of contaminated food or water, particularly pork or pork products. A wide variety of foodstuffs have been implicated in cases and outbreaks
- person-to-person: particularly within nurseries, schools and healthcare settings
- direct contact with animals
- Via contaminated blood products
Incubation period:
- Y. enterocolitica: usually 3-7 days with extremes of 1-12 days reported
- Y. pseudotuberculosis: range of 2-25 days reported (median 5-8 days)
Common clinical features:
- Y. enterocolitica:
- watery diarrhoea, abdominal pain, fever
- duration: 2 days to 6 weeks
- complications: reactive arthritis, erythema nodosum, septicaemia - Y. pseudotuberculosis:
- mesenteric adenitis, fever, abdominal pain often mimicking appendicitis
- duration: 1-37 days (average 18 days)
- complications: reactive arthritis, erythema nodosum, acute renal failure
Infectivity:
- excretion of the organism in stool may persist for several months after infection but infectivity decreases substantially after the first 4 days or so
Reference:
- PHE (2019). Recommendations for the Public Health Management of Gastrointestinal Infections