Encephalitozoon cuniculi

Question 1

What is it?

Answer 1

• a protozoa with fungal proteins within it

Question 2

What animal does it most commonly affect?

Answer 2

• rabbits

Question 3

Transmission

Answer 3

• in utero
• shed in urine of affected animals

Pathogen ingested in contaminated food and water -> pathogen moves via blood stream into kidneys -> pathogen intermittently passed in urine.
Pathogen moves from kidneys into spine -> hindlimb paresis.
Pathogen then moves up the spine to the brain -> brain tilt.

Question 4

Which systems does the parasite commonly affect?

Answer 4

• neurological
• kidneys
• eyes

Question 5

Clinical signs

Answer 5

CNS damage:
- hindlimb paralysis/weakness
- torticollis (head tilt)
- urinary incontinence
- tremors

Kidney damage:
- PUPD
- weight loss
- anorexia

Eyes:
- cataracts and uveitis

Question 6

Diagnostic options

Answer 6

• blood test antibody serology (ELISA)
• urine antigen test (PCR)
• histology (kidney PCR)

Question 7

Diagnosis - blood ELISA

Answer 7

• If exposed in past will have antibodies
• IgM (acute) vs IgG (chronic)
• very high levels can be diagnostic
• moderate levels: re-test in 4w
• if increased in 4w = diagnostic

Question 8

Diagnosis - urine PCR

Answer 8

• unreliable as intermittently shed
• used for screening groups

Question 9

Diagnosis - histology on kidney

Answer 9

• PM if housed with other rabbits

Question 10

Treatment

Answer 10

• biosecurity: isolate, disinfect environment (F10 & bleach)
• fenbendazole (Panacur) 20mg/kg PO SID (28d)
• vertigo: prochlorperazine? darkness, support with rolled up towels
• inflammation: NSAID with fluids to try and support the kidneys
• gut support
• euthanasia: if severe signs don’t respond to tx within a week

Treatment eases symptoms by reducing inflammation, but doesn’t reverse damage already done.

Question 11

Use of steroids

Answer 11

• severe immunosuppression
• WBCc can plummet
• not recommended as open to commensal overgrowth (snuffles flare up), etc