Category: skin disease

Anal furunculosis (perianal fistulas)

Anal furunculosis (also called perianal fistulas) is a distressing condition commonly affecting German Shepherd dogs and occasionally other breeds. The problem is one of chronic deep infection, inflammation, discharges and ulceration around the tail base and anus. The condition may progress to involve a large area around the back end of the dog. It can be very difficult to cure or control but recent advances in treatments are proving encouraging.

No-one really understands what causes the condition to develop. It is more common in dogs with the broad tail base and low tail carriage typical of German Shepherds. This conformation may result in poor ventilation and increased humidity of the anal area. Faecal bacteria may persist in this environment increasing the risk of infection of hair follicles and hormone glands in this area.

Underlying problems with the immune system may also play an important role. The disease has also been linked to inflammatory bowel disease and colitis. If your dog has diarrhoea they may be at more risk of developing anal furunculosis.

Anal furunculosis is very irritating and dogs with this condition will frequently lick their hind end. You may notice that your dog shows discomfort or difficulty when passing faeces. Other signs of illness such as weight loss irritability or depression due to pain are seen in severe cases.

The tell-tale signs are of matted hair, odour, bleeding and discharges from the anal area. However your dog may not let you look closely if the condition is very painful. It should be possible for your vet to make a diagnosis of anal furunculosis from looking at the diseased area (but they may need to sedate your dog for close examination). In a few cases biopsies are needed to be certain of the diagnosis.

This is a difficult disease to treat and although several types of treatment are available none is 100% effective. The diseased tissue can be removed at surgery – often, extensive treatment is needed and this may need to be repeated. If extensive surgery is performed there is a risk of nerve damage which can result in incontinence. Some surgeons advocate amputation of the tail to improve ventilation or removal of the anal sacs.

Recently, encouraging results have been achieved using drugs designed to alter the function of the immune system, and this may prove to be a very effective treatment for anal furunculosis.

Yes, check with your veterinary surgeon first, but many dogs with anal furunculosis are greatly helped by hydrotherapy. This involves the use of a shower attachment or garden hose to direct water over the affected area under the tail once or twice a day. The water should be lukewarm or cool, under moderate pressure.

Start gradually and gently and build up as your dog gets used to this treatment. For this to be effective, each session should last at least 15 minutes. A tail bandage applied to the tail will stop this getting too wet. This treatment can have a very good effect if carried out diligently every day.

Controlling symptoms is a long-term process in many cases. New treatments are being developed, but relapses may occur and permanent treatment can be needed. Anal furunculosis is well known as a difficult and sometimes frustrating disease to treat. Recent treatments have shown encouraging results but euthanasia may need to be considered if your dog is very seriously affected or if your dog’s temperament makes home treatment difficult. More than most diseases, this one calls for a high level of commitment and extreme vigilance on the part of owners. Bear in mind that long-term treatment can prove expensive.

Whilst anal furunculosis can be a frustrating and difficult condition to treat it is important to seek help as soon as possible. If the condition becomes widespread it can be impossible to control. As there are a number of different treatment options it is important to discuss your dog’s problem with your own vet so that you can work out the most appropriate course of action for you and your pet.


Living with an itchy dog is no fun – but being an itchy dog must be worse! Atopy affects around 1 in 10 dogs to some degree. In dogs the condition can cause a variety of signs: skin disease, runny nose, itchy eyes and (very rarely) asthma. If your dog persists in licking its feet or has recurrent ear or skin infections, it may have atopy. As a general rule itchy skins do not resolve without treatment; so if your dog is scratching an early visit to your vet is advisable. Itchiness is not normal, nor is it a habit.

Atopy or ‘atopic skin disease’ is a genetically-predisposed tendency to develop an allergy to environmental allergens. The most common allergens are house dust mites, storage mites, pollens (grass, weed and tree), moulds, skin dander and less commonly dietary proteins. In allergic animals, the immune system over-reacts to contact with these foreign substances causing inflammation that leads to itchiness. Dogs display this irritation by rubbing, licking, chewing, scratching and biting themselves or scooting along on their backside.

Dogs with atopy are born with the potential tendency to develop significant allergic responses. As the dog comes into contact with more and more allergens in its normal life, these allergies start to develop. Most dogs with atopy start to show signs between 1 and 3 years of age. It would be very unusual for a puppy younger than 6 months to develop signs of atopy. If your puppy shows signs of itchiness before this age it is most likely that there is another reason for it.

Some breeds of dog are far more likely to develop atopy than others and if there is a history of atopy in your dog’s family then they are more at risk of developing signs.

Your dog may have atopy if it suffers with recurrent ear or skin infections that clear up with treatment but then come back some time after when treatment stops. The body sites typically affected in dogs with atopic dermatitis are:

  • the face and ears
  • between the pads of the feet
  • in the armpits or groin area.

If your dog is forever licking at or rubbing one or more of these sites, even if you cannot see any skin lesions, make an appointment to see your vet. Typically dogs with atopy start off with seasonal disease. However, in subsequent years the skin disease will often start earlier and last longer.

If you can answer yes to the following questions there is a high chance that your dog may have atopy.

  • Was your dog younger than 3 years old when it first showed signs?
  • Is the dog mostly kept indoors?
  • Was the itchiness present before you noticed skin lesions?
  • Does your dog have reddened front paws and are the inner surface of the ear flaps affected?
  • Are the margins of your dog’s ear flaps unaffected?

Your vet should also begin to suspect that your dog has atopy based on a history of recurring skin or ear infections, particularly if these clear up over the winter and come back the following year. Atopic dogs with light-coloured coats often have brown, saliva-stained fur in sites where they lick constantly.

If your vet thinks it is likely that your dog has an allergic skin condition they will want to do some other tests. But firstly your vet should ensure that regular, prescription, ectoparasite control has been used and they may prescribe treatment to clear up any secondary skin infections.

If the symptoms are not seasonal, then your vet must recommend a strict, food elimination trial for several months. Feeding your dog a specific, truly hypoallergenic diet helps to rule out a food reaction as the cause of the itchiness.

If your dog is still itchy after all this treatment, and the diet trial, then referral to a specialist dermatologist for intradermal skin testing should be offered. Under light sedation, an area of skin over the body wall is clipped and prepared. Tiny volumes of allergens are injected into the skin and your dermatologist will monitor the reaction to these allergens in the skin to decide which are likely to be causing itchiness. Depending on the intradermal test results it may be possible to treat the condition with allergen-specific immunotherapy.

Yes. The main priority for treating atopic dermatitis is to reduce all the factors that may cause the skin to be inflammed. It is very distressing for a dog and owner when a dog is scratching all the time. The management options currently available are listed below and the combination that works for your dog needs to be tailored specifically for individual conditions:

  • It is often possible to reduce the dog’s overreaction to allergens by the use of allergen specific immunotherapy (desensitising vaccines). These injections must be given over a period of some months and in over two-thirds of dogs these help to reduce the severity of the allergy. If you are considering desensitisation you will have to be patient – improvement may not be seen for around 9 months after the course of injections starts. Following that monthly lifelong injections are required, and it is rare for the condition to be controlled without the need for other managemental or medical interventions.
  • It will be important to take particular care in preventing parastic infection. Atopic dogs are prone to sarcoptic mange infection and also more likely to become allergic to fleas.
  • Complete diets, with higher levels of essential fatty acids, may assist with control of skin conditions. Of course it is important also to avoid any dietary allergens that were implicated during the food trial.
  • Regular cleansing of the coat, ears and paws to mechanically clear surface allergens, assist wth natural skin cell shedding and improved skin barrier function will be beneficial.
  • Common recurrent yeast and bacterial infections must be controlled – ideally with regular medicated washes and ear cleaners.
  • Anti-inflammatory medications, both systemic and topical (sprays, gels, shampoos and rinses), should be employed when necessary on top of all the above strategies.
  • Other drug therapies may also be needed – steroids are cheap, but potentially have many side effects. Cyclosporin A has few significant side effects though is comparatively expensive. Antihistamines are usually cheap, with few side effects, but are invariably ineffective.

It is very rare for dogs with atopy to be cured or grow out of the problem. In fact they generally have more severe episodes each year. However, in most dogs the condition can be controlled by careful, diligent management.

If it has been possible to identify the specific allergens involved in your dog’s case, by intradermal and/or serological testing, then it may be possible to avoid things that are likely to cause reactions in your dog. For example, if your dog is allergic to pollens it may help to keep them inside when the pollen count is high or when you are mowing the lawn.

Elimination of house dust mites is difficult but regular hot washing of the bedding plus annual environmental spraying can help kill mites. Dogs with house dust mite allergy may benefit from preventing access to bedrooms, soft furnishings and carpets.

If you have any concerns about our dog contact your own vet for further advice.

Hot spots (wet eczema, pyotraumatic dermatitis)

Sometimes dogs develop a sore spot on the skin which oozes and irritates. Often this develops over the space of just a few hours. The critical step in managing these spots is to stop the dog worrying them but veterinary attention should be sought to ensure there is no underlying condition that needs treatment. In most cases early treatment results in a rapid resolution of signs.

Wet eczema is also known as ‘hot spots’ and your vet may refer to it as ‘acute moist dermatitis’ or ‘pyotraumatic dermatitis’. It is caused by infection in the surface of the skin. Bacteria are present on all dogs’ skin but in order to cause infection they must break through the skin barrier. This can occur when there is damage to the skin either through changes in the skin itself or scratching by the dog.

Once the skin barrier is penetrated the bacteria can grow and this infection causes intense itchiness and the dog scratches the site resulting in further damage and spread of the sore.

It is normally clear when a dog has wet eczema. The sores are usually obvious as they most often develop on the face and the flanks. The skin sores in this condition are extremely itchy and affected dogs are unable to leave them alone. You will see your pet continually licking or scratching at the same site on their skin. The skin sores look red and ‘angry’ and exude a moist clear discharge which has a very unpleasant smell. If the sore is left alone then the exudates may dry and crust on the surface.

Some breeds of dog (especially Labrador retrievers and St Bernards) appear to be prone to developing wet eczema. However, it can be seen in any breed. Younger dogs also appear to be at greater risk of developing wet eczema, although once a dog has had one episode of wet eczema they are likely to be prone to subsequent episodes later in life too. Wet eczema is more common in summer months and particularly if dogs have dense or matted coats.

Wet eczema is triggered by an underlying skin problem and often it is caused by the dog scratching due to itchy skin. The itchy skin condition can be due to allergy (e.g. atopy), fleas, ticks or other parasites, irritation from an ear disease or anal sac disease or from the presence of a foreign body in the skin, e.g. a splinter, grass seed or thorn.

Irritation by a drop-on anti-flea treatment or other liquid that the skin was exposed to either intentionally or unintentionally is sometimes a cause. Continual wetting from bathing, swimming or drooling are possible causes. Damage from blades during clipping is also a consideration.

Wet eczema is usually caused by another skin disease so your vet will want to identify any potential cause – the condition will not clear up unless the underlying disease is properly treated. Your vet will check to see if an underlying disease is present and if so this can be treated at the same time as the wet eczema.

Sometimes, other skin diseases such as burns, deep bacterial infections, ringworm (dermatophytosis), calcinosis cutis or some tumours can have the appearance of wet eczema and so it is important to confirm the diagnosis in case a different treatment is needed. Clipping the surrounding fur, skin scrapes and cytological examinations and full-thickness skin biopsies are all useful tests that may often be helpful. Further tests are necessary in some situations.

The most important factor in management of wet eczema is to stop further trauma to the skin. The dog must be prevented from licking or scratching at the site – depending on the site of the sore a Buster or Elizabethan collar may be necessary. If the dog is scratching at the sore then bandaging the foot may help to reduce the amount of damage done. However, the affected area should be left open to the air whenever possible as this drying effect is very beneficial in the healing process.

Hair should be clipped from the sore skin and from the area surrounding the sore patch. Often the sores are much more extensive than they appear initially but clipping should be expanded continue until the whole affected area is exposed. The skin can then be bathed and dried.

Your vet may prescribe some antibacterial shampoo or cream to rub into the wound. but in most cases this is not necessary. However, in more severe cases, (particularly if the underlying skin disease is difficult to control), steroids or antihistamines may be required to reduce itchiness and antibiotic tablets given to control infection.

If your pet has had wet eczema it is quite likely that this will recur. Risks can be reduced by keeping the coat short and clean with regular bathing. Extra attention should be paid to flea control. Regular grooming will allow you to identify any skin diseases or wet eczema lesions early.

Skin fold pyoderma

Pyoderma means bacterial infection within the skin. Usually this occurs within the top layers of the skin (superficial pyoderma), and is a common medical problem in dogs. Deep pyoderma, when infection penetrates further into the skin, is much more serious and may take months of intensive treatment to cure.

Skin fold pyoderma is a common, usually superficial, infection which occurs where two layers of skin fold over one another, creating a warm, moist environment where bacteria can flourish. Pockets of skin are very prone to infection due to the closed environment. Once infection takes hold, it tends to progress rapidly due to poor ventilation and the problems encountered in keeping the area clean. Food residues and bad teeth may compound the problem around the mouth.

This type of skin problem occurs commonly in certain breeds of dogs, particularly those with lots of loose skin, e.g. Sharpei, Spaniel, Bassethound, Pekingese and Boxers. Certain body areas are more commonly affected especially around the face, feet, lips, tail-base and vulva. Obese animals are more likely to suffer with the condition due to excess tissue folds.

Dogs with an infantile vulva – a small vulva in a relatively ‘tucked up’ position – commonly get skin fold pyoderma in the surrounding area. This may be difficult to see without close examination and may be very painful to examine in the conscious dog. Infantile vulva may be more common in bitches spayed at a very young age.

In some animals areas of moist, reddened skin with discharge and unpleasant odour are easy to see. But, often the condition may not be visible until the fold of skin is stretched open, revealing the infected skin within. Dogs may also show other signs:

  • Pain and discomfort
  • Irritability
  • Pawing at the mouth
  • Rubbing the face
  • Licking at the feet
  • Excess rubbing and licking at the bottom area

Medical treatment, using drugs of various types, often leads to an initial improvement in the condition. However because the skin pockets remain, future recurrence is quite likely. Drug treatments used include:

  • Antibiotics
  • Antiseptic washes applied to the area
  • Anti-inflammatory drugs/painkillers
  • Topical creams and ointments.

The condition is often difficult to control – it may not respond well to medical treatment or come back as soon as treatment is stopped.

Since the problem is caused by abnormal anatomy or conformation surgery can help to correct this. Surgical treatment is recommended when there is frequent recurrence. The skin folds/pockets are surgically removed, opening up the area and allowing proper ventilation of the skin and a reduction in the likelihood of recurring bacterial infection. Operations of this type include cheiloplasty (on the lips), nasal fold resection (in Pekingese) and vulvoplasty (at the vulval area). In dogs with bad teeth and skin fold pyoderma at the mouth, your vet may also recommend dental treatment.

Keeping affected areas clean certainly helps. Daily bathing with a salt solution (1 tbsp in a pint of water), followed by drying, may help prevent subsequent infection. Other antiseptics, unless supplied by a vet, should not be used.

There is variation between individuals of the same breed, so some animals may be more severely affected than others. Responsible breeders should not breed from dogs which are severely affected to reduce the risk of problems being passed to the next generation. However, a great many Sharpeis have this condition to some degree due to the characteristics of this breed.

‘Walking dandruff’ (Cheyletiellosis)

Cheyletiella infection is a form of mange that is also known as rabbit mites and walking dandruff. This is an itchy skin condition caused by small parasites living on the skin surface. The mites can be found on many animals including dogs, cats and rabbits and can be transmitted from pets to people. Early recognition is important as the condition can be simply treated.

The condition is caused by infestation with a small mite. This mite lives its whole life on the skin of a furry animal. Although the mites are small they can just be seen with the naked eye or a magnifying glass and may appear like small white flakes of skin that can move – hence the name ‘walking dandruff’.

Most healthy animals seem to have some immunity to infection and the majority of affected animals are old, young or unwell. It is most commonly seen in puppies bought from pet shops or breeding centres. Boxer dogs and Cavalier King Charles spaniels appear to be more at risk than other breeds. Puppies most commonly become infected from their mother in the first few weeks of life.

Often the first sign noticed by owners is excessive scurf or dandruff formation on their pet’s skin. This may be accompanied by scratching and later small spots can develop. Occasionally owners are more severely affected than their pet and may themselves have itchy red patches or spots on their skin.

The mites causing cheyletiellosis can move between animals and can cause itchy red lesions on people as well as pets. Lesions in people are generally very itchy and tend to affect arms, neck, chest and abdomen. Infection is most easily spread to people from cats and rabbits rather than dogs. If infection is controlled in pets the lesions on people will settle down after a few weeks with no specific treatment.

The condition is relatively easy to diagnose because the mites can easily be seen under a microscope. Small samples of skin or hair can be examined and mites and eggs will be seen in an active infection. The mites feed on the skin surface and eggs are laid on the hairs or skin surface. The previous application of flea sprays or drops may reduce the number of mites making diagnosis more difficult in dogs.

Mites can be killed by the application of topical drops that kill parasites. Your vet will be able to prescribe this for you and tell you how to use it effectively. Since the infection can spread between animals, all animals that have regular contact with the infected individual should be treated at the same time (even if they are not showing any signs of disease). A number of treatments may be required over several weeks.

There is no product specifically recommended to kill any mites in the environment, e.g. pets’ beds and carpets, but an environmental flea spray may help in this respect.

Acral lick granuloma

Lick granulomas are moist, fleshy pink sores usually on a dog’s legs. They are caused by excessive licking at the site and are frequently caused by an underlying disease that needs to be properly diagnosed and treated. If you suspect that your dog has a lick granuloma you should seek veterinary advice as soon as possible.

A lick granuloma is a red, sore patch of skin caused by the trauma of your dog licking continuously at one site. Most lick granulomas occur at a site that is easy for the dog to access – the left foreleg is often chosen as it’s comfortable to reach when the dog is lying down.

Many lick granulomas are the expression of an underlying itchy disease but the itchiness tends to express itself in a focal rather than generalised manner. In other cases, the licking may be a manifestation of pain (e.g. arthritis in older dogs) and might have been triggered by some trauma in the area.

An initial stimulus causes the dog to start licking at the site, this leads to infection and scarring and the area itself then becomes itchy because of the damage that has already been done and so becomes self-perpetuating. Since most of dogs with lick granuloma have deep infections, they benefit from a prolonged course of antibiotics.

It is thought that the act of licking causes the release of endorphins (natural opiates which provide a sense of well-being) in the dog’s brain. The dog soon learns that licking brings about this pleasant feeling, and keeps on licking. As the process continues, a fleshy pink mass known as a ‘granuloma’ may develop at the site. The area will usually always be moist and may become particularly red and inflamed if infected.

In some cases, people living with the dog may notice excessive licking of the affected area. However, many dogs lick themselves only when the owner is not present.

In many cases the initiating factor is an allergy or infection (e.g. ringworm) that causes the skin to be itchy or painful. However in some dogs the initiating factor is minor when compared to the psychological element. Nervous and highly-strung dogs appear to be more likely to develop lick granulomas but it can also be seen in dogs that spend a long time alone or receive insufficient exercise or mental stimulation.

Because they take a long time to develop, lick granulomas are most often seen in middle-aged or older dogs. Large breed dogs seem to be predisposed to develop them. Since endocrine and metabolic diseases may also be an underlying cause (e.g. decreased function of the thyroid gland) and these diseases tend to occur in older large breed dogs, these patients are overrepresented. Dogs may start to lick a site because of an underlying problem (itchiness or soreness at the site) but over time the habit becomes engrained and the dog simply derives pleasure from the act of licking.

Lick granulomas have a typical appearance. However, it is possible for other conditions (particularly infections and tumours) to mimic this appearance and it is important to be sure that the sore is not a tumour before treating it as anything else.

There are many underlying causes for lick granulomas and your vet will want to rule out these because if an underlying cause is not treated the lick granuloma will keep recurring.

Proper identification of the underlying cause is crucial to the success of the therapy. If such cause is not identified, lick granulomas may be extremely difficult to resolve. Antibiotic therapy will be necessary to reduce infection in the tissue. Due to the depth of the infection it is common to use oral antibiotics for months.

All therapy will need to be continued for at least 4 weeks after all signs of the sore have resolved. Even if a granuloma can be completely resolved there is still a risk of it recurring once treatment is stopped. Some vets recommend creams to rub into the wound – those containing local anaesthetics may help to reduce the desire to lick. Application of aversives like bitter apple may also limit licking. Alternatively, drugs that interfere with the transmission of neuropeptides (important for the transmission of pain and itch) can be used. Capsaicin, the active ingredient of chilli pepper, can be used topically on the margin of the granuloma.

One of the reasons dogs continue to lick the site is that licking the sore area releases natural endorphins (morphine like substances) which make the dog feel good. In some dogs administration of an opioid drug, e.g. hydrocodone, can not only reduce irritation but may also fill the need for endorphins that the dog may be experiencing.

In really severe cases desperate measures such as surgical excision of the sore may be required. Surgical wounds at the site may not heal well either and if the dog starts licking at the stitches you may quickly be in a worse position than before surgery. You should think very carefully before embarking on this treatment and be sure you have discussed all the options with your vet.

Many dogs have underlying allergies or endocrine diseases that need to be addressed to ensure resolution of the existing granuloma as well as to prevent the recurrence. Additionally, addressing the potential psychological factors is important and some cases may respond to simple changes in environment (reducing stress or boredom). Reduction in boredom can be achieved by providing company for the dog, increasing exercise and training. In more difficult cases mood-altering, antidepressant drugs such as Prozac or amytriptiline have been advocated. There have been some reports of success with acupuncture.

Acral lick granulomas are extremely frustrating to treat. There is no simple cure and any success will only be achieved by a dedicated and consistent approach of both owner and vet.