A dog can suffer from interdigital pyoderma, a condition also known as interdigital dermatitis or pododermatitis that causes problems on the feet. Any breed can contract the condition, but some breeds, including German shepherds, are predisposed to it. Because numerous diseases can cause interdigital pyoderma, a diagnosis of the underlying cause will help with treatment.
Interdigital pyoderma is a description of a symptom rather than a diagnosis of a disease. It refers to the appearance of inflammation, sores and lesions on any part of the foot caused by infection. Since numerous diseases can cause a secondary foot infection, interdigital pyoderma is considered a symptom of an underlying problem.
Allergies can cause itchy feet, and excessive scratching can lead to the onset of interdigital pyoderma. It can accompany autoimmune diseases such as lupus and pemphigus. Other diseases that manifest with interdigital pyoderma as a symptom include pancreatic cancer, liver cirrhosis and cutaneous lymphoma. Hookworm infestation and bacterial infections are also possible causes.
The symptoms will vary based on the cause of the infection. Claws may be soft and break easily. The footpads may become soft and spongy or have ulcerated sores on them. Nails may appear brittle and discoloured. The toes may look swollen and have sores between them. A dog may bite and lick his feet excessively.
Veterinarians use several ways to diagnose interdigital pyoderma. A thorough examination of the affected area helps to associate the symptoms with a specific disease. Skin scrapings are sent to the lab for further assessment. If a dog's foot pads are affected, biopsies are necessary. Several biopsies may be done to find characteristic lesions and to obtain a definite diagnosis.
The treatment of interdigital pyoderma will depend on the underlying cause. For instance, if a bacterial infection is the cause, a six- to eight-week course of antibiotics is usually necessary. A veterinarian may prescribe a topical medication to alleviate itching and protect any sores from worsening. Antifungal drugs such as itraconazole or ketoconazole are usually prescribed for fungal infections.