Symmetrical Lupoid Onychodystrophy

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SLO is an autoimmune disease of dogs which can cause severe claw problems in otherwise apparently healthy dogs. It is characterised by the loss of claws from more than one paw - eventually all claws may be lost. Other symptoms may include: receding quicks, secondary infection (often with a strong smell), claw splitting (usually down the back of the claw), pain, distorted/twisted claws and lameness.

A firm diagnosis can only be reached by the biopsy of a claw, dewclaws usually being used for this. In the absence of an available dewclaw it is necessary to amputate a toe at its bottom joint in order to do the biopsy. In many cases, this is considered an extreme step to take, and is not strictly necessary. If the dog is showing signs of SLO, treatment using the latest protocols can be started - if they work, it largely confirms the diagnosis, even without the biopsy.

Modern treatments include the use of essential fatty acid (EFA) supplements, antibiotic treatment with tetracycline and niacinamide (nicotinamide). Removal of claws as they become loose can help to alleviate pain, but generally isn't necessary. Although there are few studies to scientifically confirm the results, the treatment appears to be effective. Once the disease is in remission, supplementation may need to be continued for life to prevent relapse.

SLO can appear in all breeds, including crossbreeds and mixed-breeds, although some breeds seem to be more susceptible than others. It is not infectious or contagious - other dogs which come into contact with it cannot contract it. It appears to be spontaneous, and there is no evidence of an hereditary factor - because of the absence of studies and the small number of known cases though, there is little proof of this other than anecdotal evidence.

It is likely that it is a newly-recognised old condition, rather than a new disease. It is probably more common than it appears, because in many cases it is not diagnosed correctly. In response to the lack of information available, a number of owners of dogs with this condition have gathered on the Internet to share information and support, and to discuss management and treatment protocols.

Owners of dogs with the condition, and anyone else who has an interest, can share support and information on the subject by joining the Canine Symmetrical Lupoid Onychodystrophy Mailing List, where they can discuss their problems with other owners, some of whom have been treating their dogs for many years.

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I know of no specialist vets who deal with this disease, although the occasional skin specialist may know a little. Breed specialist vets will know no more about it than any other, so if you like the vet you currently use there's no reason to change.

There was a study recently published in the UK's Journal of Small Animal Practice, which has quite good photographs and may help to show you what it looks like as well as providing information:
Page One, Page Two, Page Three, Page Four, Page Five, Page Six.

The most recent treatment protocol is published on the web, so you may wish to print the page and take it to your vet. ( Dead link :-( domain expired at some point [PJW] )

If your vet wants to know more about the use of EFAs (Essential Fatty Acids, ie. Omega-3 and Omega-6 oils) in the treatment of SLO, he/she may find this study interesting. ( They now have several studies on SLO on their Autoimmune Disease page [PJW] )

Created by A.J.Chee - 6th June 2001.

[Last update by P.J.Wise - 17th December 2016.]

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© 2001 Andrea J Chee

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