Disease Spotlight: Acral Lick Dermatitis (ALD)

What are acral lick sores?

Acral lick dermatitis (ALD), also called acral lick granuloma or acral pruritic nodule is one of the most frustrating diseases that pet parents, family veterinarians and veterinary dermatology specialists encounter. The sores develop from compulsive licking, usually of a lower limb. Small to large, firm, proliferative, and ulcerative plaques develop.

What causes the sores?

Most people think that it is psychological disorder but one study showed that 50% of cases have organic disease that leads to the urge to lick. For example, arthritis in a nearby joint, a demodex mite overgrowth, a deep fungal infection or an underlying tumor can be inciting factors. As veterinary dermatologists we typically see patients with ALD secondary to allergy.

What can be done if my pet has an ALD?

At ADRC we investigate allergy as a cause of the ALD before labeling the patient as having a psychogenic condition. We recommend a thorough review of the patient’s history to get a feel for progression. Historical information such as response, or lack of response, to previous therapy and relapse rate help us determine which allergy should be pursued first. A recent publication reported bacterial infection was found in 94% of cases, scar tissue in 80% of cases and hair foreign bodies in 32% of cases. Most people have experienced an ingrown hair at some point in their life. A single hair can cause quite a bit of inflammation and discomfort, now imagine how irritating dozens of hairs would feel trapped under the skin surface. In addition to therapy for the underlying allergy we also address secondary infection and scar tissue. Therapy is usually needed long term.