What is a lick granuloma?
Otherwise known as acral lick dermatitis this problem starts off as an area of hair loss and reddened skin due to licking, usually in the region of the wrist or carpal joint on the front legs. In other words it looks like a hot spot. Due to chewing and licking erosion occurs with a sharp demarcation between normal and affected skin. Once the area is ulcerated the condition becomes self perpetuating and chronic. Sometimes other sites such as the ankles (hocks) on the hind leg are affected. As healing occurs the dog appears more attracted to the site.
Is there any breed disposition?
The condition occurs mainly in medium to large breeds, particularly Dobermanns, Great Danes, Labradors, Retrievers and Irish Setters. However any breed can be susceptible.
What is the cause?
The reason why dogs develop acral dermatitis is not definitely known. Many theories have been put forward. Psychological factors, stress or boredom, may initiate the condition. It should be noted that although it can occur on the hind limbs, the anterior and lateral aspects of the fore limbs are most commonly affected. These are considered to be areas that the dog can constantly lick while lying in a normal position. The chronic nature of the condition is often associated with a deep bacterial infection. Another commonly quoted cause is arthritis – aching joints.
How is it diagnosed?
The site and appearance of the lesion is a major guide to diagnosis. Skin biopsies are often taken if (a) there is no response to treatment and (b) to rule out other causes such as mange. If there is the possibility of arthritis in the underlying joint radiographs may be taken.
What is the treatment?
Treatment is largely empirical, high dose antibiotics for protracted periods, often months, is routine treatment in order to overcome deep infection (pyoderma). Prevention of licking by the use of Elizabethan type collars or bandaging are also commonly employed. In addition steroids injected into the lesion sometimes brings about a good response, as does behaviour therapy and ‘mood modifying’ medication. These are drugs that include sedatives and antidepressant drugs are frequently used ‘off licence’ in stubborn cases of acral dermatitis, often with spectacular results.