Tritrichomonas fetus

Question 1

What is the importance of TTF?

Answer 1

one of the most common infectious causes of colitis in the domestic cat. The infection is widespread in catteries and shelters; and, while remission of diarrhea may occur over time, persistence of the infection is common.

Question 2

What is the pathogenesis of TTF

Answer 2

Colonises the distal ileum and colon, creating a lymphoplasmacytic and neutrophilic colitis with diarrhoea
presumed to be transmitted from cat to cat via the fecal–oral route. Trichomonads do not form true cysts and therefore do not persist for more than a few hours under clean, dry and aerobic conditions

Question 3

Outline the clinical presentation of TTF

Answer 3

a waxing and waning large bowel diarrhea.12,
The duration of diarrhea in the published literature ranges from 1 day to 8 years, and 59% of owners report that their cat has had diarrhea ‘since adoption’.
Frequency of bowel movements ranges from once to eight times a day; the feces often contains mucus (59% of cats) and/or fresh blood (46% of cats), and there may be accompanying straining (43% of cats).
Diarrhea is typically semi-formed to ‘cow pie’ in consistency and malodorous. In most cases infected cats maintain good health, and a normal appetite and body condition, which presumably reflects confinement of the infection to the colon. However, some kittens will develop fecal incontinence, and overt swelling and inflammation of the anal region from faecal scalding

Question 4

What is the typical cat with TTF?

Answer 4

Can vary in age but often around 1 year
Often from multicat places
Often improve with AB tx but recurs once this is stopped
presumably due to a decrease in the population of bacteria in the colon on which the trichomonads thrive and not a direct effect of the antimicrobial drugs on trichomonad viability

Question 5

How do you dx it?

Answer 5

dentifying the organism on a fecal wet mount examination, after culture of feces in media that foster the growth of Tritrichomonas species, or by PCR performed on DNA extracted from a fecal sample

Question 6

Outline the use of f+ wet mount examination

Answer 6

f+ must be fresh and d+
Sens <14%
Hard to diferentiate with other species sometimes

Question 7

Outline the use of culture of f+ for dx

Answer 7

Needs to be done in house

Sens 55%

Question 8

Outline the use of PCR

Answer 8

Can still get false -ves

But the most sensitive option

Question 9

How should you collect a f+ sample?

Answer 9

(in order of preference): (1) passing a red rubber catheter into the proximal colon for the instillation and recovery of several milliliters of sterile saline; (2) inserting a fecal loop per rectum into the proximal colon; or (3) collecting a freshly voided specimen free of contaminating litter

Question 10

How can you ensure you f+ sample is the best it can be?

Answer 10

only use d+ samples
Ensure no ABs have been given for 7d
Do not refridgerate if doing tests other than PCR

Question 11

How do you tx TTF?

Answer 11

Ronidazole
5% of cats will experience RDZ neurotoxicity signs including lethargy, inappetence, ataxia and seizures
Side effects of RDZ in cats generally resolve if the drug is withdrawn immediately, though may continue to worsen for the next few days before slowly subsiding, and may require intensive emergency care

2/3 will resolve, 1 will have partial or no resolution

Cannot be sure cats have fully been treated or the TTF has been supressed to a level that means it may recur. Always retest if concerned

Question 12

What happens if you do not treat?

Answer 12

80% cats will undergo resolution in 2 years

Consider all +ve cats a risk to others