VETERINARY TOPICS NO. 31
ANAL FURUNCULOUS (2)
by Trevor Turner BVetMed, MRCVS, FRSH, MCIAb, MAE 
 

 


Of all the topics I have written about in the column, none has stimulated more reader response than anal furunculous;  letters, telephone calls, e-mails and even a couple of comments to me from some people at shows.

To date all the dogs involved have been GSD's with an age range of under one year to over 10 years.  The exception is a 10 years old Pembroke Corgi bitch, apparently she developed the problem early this year. The owner e-mailed me to comment that her vet, who has been in practice for over thirty years has never seen this condition “in a bobtail before.”  I would tend to agree. I remember one of the treatments advocated about forty years ago was amputation of the tail of the GSD because it was considered that with the increasing angulation seen in the breed, the close lying tail prevented air circulation around the perineal area and in consequence allowed the infection to spread.

This particular dog is interesting because the owner’s case history is absolutely typical even if the breed is anything but so. I would certainly agree with her  veterinary surgeon. I have never seen a case of anal furunculous in a Corgi but if one accepts that the condition is immune mediated in origin there is really no reason why Corgis should not be affected just like many other breeds.

The progress of the disease in this dog is interesting and has obviously been carefully recorded by the owner.  Initially it was noted that the anal region appeared wet and on investigation the owner found the skin around the anus was red.  This was then followed by the fistulous tracts which appeared first on one side and then the other. It is often at the red and wet stage that veterinary surgeons will pick up early signs of the condition, often when the dog is presented for routine vaccination, etc.   In this particular case the dog was prescribed Cyclosporine without delay. The owner mentions it cost £93 for thirty capsules.  The original dose was two 50 mg capsules per day. As I mentioned in the previous article the response was little short of dramatic and the dose was soon reduced to just one capsule a day. This particular dog does not appear to be showing other problems such as bowel syndrome and this may be due in part to the fact that she was fed a normal diet of tripe and wholemeal biscuit.

Obviously some of the cases that have been reported to me in GSD's have clearly had a multiplicity of problems including most commonly IBD (Inflammatory Bowel Disease)  Treatment of the bowel problem as well as the anal furunculous is imperative but this of course increases the cost to the owner since the provision of special diets, be they commercial or home prepared inevitably involves extra cost, the cost of which in the case of suspected dietary allergy can be lifelong.

From your response one factor stands out, Cyclosporine although frighteningly expensive, nonetheless evokes a better response than any of the other methods of treatment in anal furunculous that are currently practised.

These results have been in accordance with the figures quoted by Dr Bryden Stanley in her presentation at BSAVA congress in April.  She reported results using Cyclosporine of 100% improvement in clinical signs with an 80-8=90% of resolution of lesions.

In the studies quoted long term results were also far more encouraging than those she quoted with other methods of treatment (60-90%).  With Cyclosporine recurrence is quoted at 30-50%.  This also appears to be associated in the main with anal sac problems. I am surprised under the circumstances that anal sacs are not removed earlier in the disease. Considering the cost of Cyclosporine, operation to remove the anal sacs would be very cost effective it is reduced the need to repeat the courses of Cyclosporine which seems to be the trend according to my correspondents.

The good news is, of course, this work does appear to indicate that the dose of Cyclosporine can be reduced by up to 75% with the introduction of another drug, Ketaconozole, which prevents the breakdown of Cyclosporine by the liver and thus a much lower dose can be used.

Ketaconozole is itself an expensive drug but only approximately one third the cost of Cyclosporine.  Thus overall a combination of the two drugs can become almost affordable.

Therefore the outlook is a lot better than it ever has been for dogs with anal furunculous but although the initial short term results of Cyclosporine appear little short of miraculous be forewarned that relapses can and do occur, necessitating further courses of the drug.  Furthermore it does appear that even with the initial dramatic improvement the Cyclosporine should nevertheless be continued for three to four months otherwise relapses are likely to occur. However if these do occur the lesions can be treated far more effectively by surgical means and if the anal sacs are removed as soon as possible you have then done everything possible to ensure this awful condition is kept in check.

One final word, as a result of all the research I have undertaken into this condition particularly recently, I am more than convinced than ever that if I decide to enquire a German Shepherd Dog I would endeavour to secure the highest level of pet health insurance that I could afford!

© Trevor Turner – jean.trevor@virgin.net

15th June 2003.