Colitis...could it be?

It's me again, with my weekly obsession about my kittens...who still have diarrhea after treatements for...
Worms of every kind
Coccidia
Gardia
Every other parasites
etc....everything! they told me they got the meds for everything! And since all the meds didn't work....they got the very costly "probiotics" to help to get their stomachs on the track, and it's the sixth day they are on it now. With absolutely no positive results.
Now I called the vet on Saturday morning because little Luna had a very mucus-y stool...and I mean about 80% mucus! So I was quite alarmed. Add that to the fact that the little thing kept farting everytime she would jump or mew. (Wich sometimes ended up with a bit of mucus on the carpet...*sigh*)
Said vet told me that it might be Colitis, because of the mucus (but there's no blood at all) and to call back on Monday if it hasn't got better.
Well, of course, it isn't better, I'm getting discouraged that it will ever be ok.
Now Timine and Luna both have a lot of mucus in their stools...
I know nothing about Colitis, but I would think that this is not something that gets from one cat to another? Is it possible? They both had mucus in there for a long time....but now it's worst, since I start the probiotics....

This article that someone showed me here is quite interesting...could it be?

"Tritrichomonas foetus1, 3, 4, another cause of chronic diarrhea in cats, is currently under investigation. It is a protozoal
organism that has been easily mistaken for Giardia when observed under the microscope.1 Unfortunately, this organism has not
been responsive to antimicrobial therapy, and cats can take up to three years (average of five months) to recover.3 It has been
known to cause a waxing and waning, cow pie form of diarrhea that may have a strong odor to it as well as blood and mucus.2,3
Fecal consistency may improve with antimicrobial therapy, but once medication is stopped the diarrhea usually recurs worse than
before since antimicrobial therapy does not eliminate the infection.2, 3, 4
The mode of transmission is from cat to cat through the fecal-oral route,3 so keeping infected cats isolated from other cats is
a good idea. Disinfecting with dilute bleach has been shown to kill the organism, however daily disinfecting does not appear to
alter the course of the infection in affected cats.3 The good news is, so long as there isn't a co-existing condition (i.e.,
cryptosporidiosis, FeLV, FIV...), cats infected with Tritrichomonas foetus have been known to spontaneously recover. It may take
some time, however.

I hope this helps.

Laurie Peek, DVM"

So anyone got an experience with Tritrichomonas foetus ?? It might help a lot.