Culture and sensitivity testing

I wanted to start a thread on culture and sensitivity testing on pus from an abscess, wound or nasal/eye discharge to get some general feedback. Looking at the US websites, they seem to advocate culture and sensitivity testing ahead of any antibiotic use to ensure that they have identified the correct infection and prescribed the right antibiotic.

http://www.bio.miami.edu/hare/culture.html

Its my understanding that not all white snot is pasturella and can be other infections. Often making Baytri sometimes ineffective. Culture and sensitivity testing can identify that the infection is resistant to some antibiotics and would clearly show the correct antibiotic to use.

Do people automatically do a culture and sensitivity test ahead of antibiotic use?

If a bunny is seriously ill, they obviously will need immediate antibiotics started. I wondered, if there was time, would the culture and sensitivity testing be something to be considered? It would depend on the speed of the testing in the Uk vs USA (could be dangerous to wait a week for a test if it takes that long) and the cost involved.

I would welcome others views on testing.

Only do MC+S if unresponsive to Enrofloxacin (Baytril) or Trimethaprim/Sulphamethoxazole (Septrin)

MC+S on Rabbit pus is pointless as the pus is usually sterile. So to MC+S an abscess a swab needs to be taken from the abscess wall.

I agree with the above.
When one of my buns had a very bad upper respiratory infection it was initially thought to be pasturella. He was put on baytril and then septrin but they had little effect so the vets took a swab of the nasal discharge for a culture and sensitivity test.
I can't remember how much it cost but it wasn't expensive and I think the results took about a week.
The results showed it was not pasturella but E. coli, he was started on depocillan injections and tiacil for his eyes which cleared the infection after a few weeks

Thanks for your replies.

I notice that I omitted the link by Dana Krempel to culture and sensitivity, so I will give it now

http://www.bio.miami.edu/hare/culture.html

I just wonder by not doing c and s routinely, whether we are allowing rabbits to remain on useless antibiotics for longer than necessary. This article seemed to make sense to me.

Would the pus be sterile Jane, because it wasn't taken high up? Im thinking of a nasal discharge mainly. What would make it sterile - excuse my thickness.

As in Pegasys case, which the articles support, the discharge wasn't pasturella and a swab eventually revealed this.

I'm no expert on C&S testing, but I do know that they're useless for Urinary Tract infections too because the bacteria dies on contact with air, even if taken straight from the bladder using a needle

abbymarysmokey said:

even if taken straight from the bladder using a needle

Click to expand...

OUCH !!!!!!!!!!!!!!!!!!!!! :shock:

I think that routinely taking cultures from nasal passages is not really necessary. Most RTI's will respond to either Baytril or Septrin provided the correct dose is given
Also in some cases the pocket of infection is deep in the Buns nasal passages so a false result may be given if only a superficial swab is taken.
I guess for the private owner who wanted an MC+S done straight away for a Bun with an RTI then fare enough. Although in my unqualified opinion it is an unnecessary step to take at the outset. certainly from a Rescues point of view it would be yet another financial outlay as most labs charge about £40 for MC+S Testing.

Abscesses are a different entity and a swab of the abscess wall taken during debridement/ abscess capsule removal would be helpful. Many Vets tend to only think of giving Baytril for abscess treatment. But many abscesses, particularly Dental ones, dont respond well to Baytril at all. A MC+S would give less 'confident' Vets proof of the need to prescribe 'off licence'.

I think testing is a great theory but not very useful in practice - pus, almost by definition, indicates an inflammatory response aimed at getting rid of the infection, and hence finding 'live' bacteria in pus is very unlikely. Most accessible infection sites are therefore unlikely to get a good swab.

I also did a stint working in a pathology lab a good number of years ago and can honestly say that it's pretty hit & miss whether they culture anything from the samples anyway! And if there's more than one type of bacteria present in the swab, it can affect the way they grow in the lab and you might end up getting a false result for which bacteria is actually causing the problem.

I think that if a test gives a good positive result, then it tells you with confidence what type of antibiotic to use, but if you get a negative result, it doesn't necessarily tell you anything at all. By the time you've waited for a culture to be taken, grown and results sent back, you could be a week down the line so I wouldn't really be very happy waiting for results before starting on any antibiotic.

Thats disappointing Alison. Dana's article seemed so positive.

How long would you give it before changing Baytril to something else, if no improvement in a bunny?. Any idea on what the length of time would be for a course of Baytril for Pasturella? Would it also be a different length of time for an abscess or eye infection?

Jane, what would be your preferred antibiotic for an abscess for one of your buns?

I had it done on Marcelly big bum Raine after batril wasn't working and I had the white snot just coming out of the one nostril. It wasn't dear but cannot remember how much it was exactly now. We thought it was pasturella but the symtoms didnt really fit as it was not a continuous thing, anyhoo, the results came back clear for everything except for citrobacter freundii, 3 weeks on 9mls a day of septrin did the trick money well spent for me as it was a quicker result knowing what we were dealing with

My buns carry the staphylococcus aures. bacteria.I have written a post under the title which you may find interesting.I have cultures done every time with my buns.Maizey had snuffles and that was due to the staph bacteria rather than pasturella.My rabbits have had abscesses in their paws and Ear infections every culture has come back with the staph bacteria.The abx I now use is ceporex.Some of my buns carry a very virulent strain of this bacteria.I have lost Maizey,Bugsy and Barlie to It.I have three left which seem to have a less virulent strain and respond well to abx.

C&S can be useful, BUT... It is often very difficult to be sure which bacteria is responsible when culturing nasal discharge as the nose is designed to catch bacteria inhaled and so has a really varied populations. And, as Jane mentioned, culturing pus is rarely useful as the pus is a mass of dead cells and bacteria, the best option is to take a piece of the tissue around the abscess when it is removed and culture that as it contains the 'pyogenic membrane' where bacteria actually live and multiply. There's also a problem with the delay between collecting the samples and receiving results as most vets post them to labs and bacteria may not survive this time. Where there is a definite localised area of infection so that a representative sample can be taken I'd always advocate it, but often we rely on using antibiotics and only investigating further if the response is not positive.
We have an incubator set up so can culture samples cheaper on site and get faster answers so I now do far more as I feel that results are likely to be more accurate.

Marie thank you for your very helpful post. Its great you have the facilities in house to culture samples.

Maizey, thanks for taking the time to post. I am so sorry that you lost your beloved bunnies to this awful infection.

Denny, it seems it was fruitful for your bunny and thats good to know.

It was Raine but I did go through the x ray mallarky as well to rule out teeth probs first.

Found my bill, it was £25 for the culture and sensitivity test which I thought wasnt bad as I was expecting around the £200 mark:lol: