Interdigital Dermatitis (Pododermatitis) in Dogs: Symptoms and Treatment

1 What Interdigital Dermatitis Is

An interdigital cyst is a chronic inflammatory lesion that develops between a dog’s toes. Despite the name, it is not a true cyst; it is a granulomatous, polymorphic cluster of small nodules, which is why the condition is also known as interdigital pyoderma.

2 Recognizing the Symptoms

In the early stage the lesion appears as a small papule that gradually enlarges into a nodule 1 to 2 cm in diameter. The nodule is purple-red, shiny, and fluid-filled (fluctuant). Squeezing it may cause it to rupture and discharge a blood-tinged exudate.

A single nodule or several may appear on one or more paws. When a foreign body is the trigger, it usually occurs as a single nodule on one front paw; when bacteria are responsible, multiple nodules are more common. The site is painful, the dog walks with a limp, and it frequently licks or bites the affected paw.

3 Treatment Options

For a foreign-body cyst, remove the embedded object and then apply warm foot-bath therapy: soak the paw for 15 to 20 minutes, 3 to 4 times daily, for 1 to 2 weeks, which resolves the inflammation.

For a bacterial cyst, use a systemic antibiotic to which the organism is sensitive, but at a high dose and for a prolonged course. Alternatively, the affected tissue can be surgically excised and covered with an antibiotic dressing; after a few days, soak or flush the area daily with an antiseptic. A Staphylococcus bacterin and toxoid may also be used.