Yersinia

Include:

Y. enterocolitica

Y. pseudotuberculosis

Y. pestis

Characteristics/Epidemiology

Colonise domestic animal.

Pathogenesis/Transmission

V and W antigens are virulence factors.

Transmission by ingestion of contaminated mean (esp port).

Clinical significance

Entercolitis

Ulcerative lesions in terminal ileum

Necrotic lesions in Peyer's patches

Enlargement of mesenteric lympoh nodes.

Symptoms

• Fever
• Abdominal pain
• Diarrhoea

Can have RLQ pain and leucocytosis -> indistinguishable from appendicitis clinically

Last 1-3 weeks.

Complications

• Reactive polyarthritis
• Erythema nodosum
• Exudative pharyngitis
• Septicaemia

Laboratory identification

Cultured on MacConkey or CIN agars

Motile when grown at 25 degrees, but not at 37 degrees.

Grows well at 37 degrees (not most of the other enterobacteriaceae)

Most are Lac-.

Serology test for anti-Yersinia antibodies

Treatment

First line: Ciprofloxacin

Second line: Trimethoprim/sulfamethoxazole

Prevention/immunity

Food hygiene and preparation.

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Things to revise/add later:

Bibliography:

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