Case 38: A case of polyarthralgia following an episode of diarrhoea

Question 1

What is CIN a selective medium for?

Answer 1

Growth of Yersinia enterocolitica

Question 2

What is the optimal incubation temperature for Yersinia enterocolitica?

Answer 2

25˚C

Question 3

What is the colony morphology of Yersinia enterocolitica on MAC?

Answer 3

Large and small pink colonies

Shiny

Normal flora

Question 4

What is the colony morphology of Yersinia enterocolitica on DCA?

Answer 4

Large pink colonies

Normal flora

Question 5

What is the colony morphology of Yersinia enterocolitica on CAMP?

Answer 5

None - no campylobacter

Question 6

What is the colony morphology of Yersinia enterocolitica on CIN?

Answer 6

Large, shiny, gooey colonies

Yellow and pink

Question 7

What is the Gram morphology of Yersinia enterocolitica?

Answer 7

Gram -ve rod

Question 8

Which antigens will be present in Yersinia enterocolitica infection?

Answer 8

O and H antigens

Question 9

What is reactive arthritis?

Answer 9

Patients present with arthritis accompanied by urethritis and conjunctivitis (Reiter’s syndrome)

Develops 2-4 weeks after GIT or genitral tract infection

Acute onset with fever and malaise

Arthritis involves lower extremities, no more than 6 joints

Question 10

What is the common surface antigen present in those suffering from reactive arthritis?

Answer 10

HLA-B27

Question 11

Which common organisms cause reactive arthritis?

Answer 11

Salmonella, campylobacter, shigella, yersinia, chlamydia and neisseria

Question 12

What is the significance of the serological test in reactive arthritis?

Answer 12

Test serum for Ab for Yersinia

Question 13

How can reactive arthritis due to Yersinia be acquired?

Answer 13

From milk

Question 14

How should a patient with reactive arthritis due to Yersinia be managed?

Answer 14

Let infection run its course

Anti-inflammatories for arthritis