Symptoms and Treatment for Vasculitis in Dogs

Types of Vasculitis in Dogs

As mentioned, vasculitis can either be a primary condition or a secondary to a concurrent health problem. The inflammation of the vascular wall of the blood vessels can be due to causes like infections and immune-mediated triggers, or endotoxins that affect the integrity of blood vessel walls.

Unfortunately, more than 50% of reported cases of vasculitis in dogs are considered idiopathic, where no apparent cause was found. In such cases, symptomatic and supportive treatment is usually the best way to manage and control the condition.

Infectious causes of vasculitis in dogs can be differentiated depending on what organism is causing the infection and triggering the inflammation. Here are some of the common causes of infectious vasculitis in canine patients:

Bacterial causes:

• Septicemia
• Bacterial endocarditis
• Bacterial blood infections

Viral causes:

• Canine parvoviral infection

Rickettsial and Parasitic causes:

• Ehrlichiosis
• Babesiosis
• Heartworm infection

Non-infectious causes of vasculitis, also termed immune-mediated vasculitis, are usually triggered by substances such as drugs and food. Underlying internal health problems such as cancer and autoimmune disease also fall under non-infectious causes of vasculitis in dogs. Here are a few examples:

• Adverse drug reactions
• Food allergy
• Vaccine reactions
• Neoplasia (cancer)
• Arthritis
• Systemic Lupus Erythematosus (SLE)

Symptoms of Vasculitis in Dogs

Since blood vessels are pretty much found in all tissues and organ systems in a dog’s body, vasculitis can have a wide range of symptoms depending on the organ system affected. But vasculitis in dogs can be categorized into two general types: cutaneous vasculitis and systemic vasculitis.

Cutaneous vasculitis is the most commonly reported type of vasculitis in dogs. It affects the small blood vessels housed under the skin and causes a variety of skin diseases in dogs. The damage on the endothelial wall of skin blood vessels results in reduced oxygen perfusion and nutrient deprivation of the skin tissue, leading to cell death and necrosis.

Clinical presentation of cutaneous vasculitis varies depending on the size of the blood vessels affected, the type of inflammatory cells infiltrating the blood vessel wall, and the underlying cause of the inflammation.

Early stages of cutaneous vasculitis usually present with bruising and pitting edema (soft tissue swelling). Purpura (ruptured blood vessels) is often seen in cutaneous vasculitis, along with hives and blood blisters. As vascular injury starts to progress, oxygenation becomes severely compromised and the affected skin tissue will start to become black (necrotic). Ulcerations will eventually develop, increasing the risks of secondary bacterial infection.

In some cases of canine cutaneous vasculitis, the skin of the affected animal will lose its hair. Crusting and scaling are often seen along with hyperpigmentation and ulceration. Skin lesions associated with this type of vasculitis are often painful when touched or pressure is applied. Regions commonly affected in cutaneous vasculitis are the paw pads, the tip of the tail, ear pinna, and nose. Severe cutaneous vasculitis will often present with a more generalized and extensive skin lesion.

Vasculitis affecting different organ systems other than the skin is considered systemic vasculitis. This is the most common manifestation of vasculitis in dogs that are triggered by systemic health problems such as viral, bacterial, or parasitic infections and cancer.

Systemic vasculitis has a more generalized set of symptoms and will highly depend on the organ system affected. Fever, lethargy, pain, and weight loss are often seen in dogs with systemic vasculitis.

Diagnosis of Vasculitis in Dogs

Because of the wide range of symptoms and the potential to affect several organ systems in the dog’s body, a definitive diagnosis can be tricky and complicated. A complete and detailed history, along with a thorough physical exam is important to arrive at a conclusive diagnosis. It is imperative to determine if vasculitis is infectious or non-infectious because the treatments between the two are significantly different.

Your vet will request a complete blood count and chemistry to check for any underlying systemic causes of vasculitis. Blood cultures may be needed if an infection is suspected, and specific blood parasite titers may be indicated if the initial blood test results indicate a possible blood parasite infection.

Confirmatory diagnosis will come from histopathology (biopsy) of the affected tissue or organ. This is highly beneficial in diagnosing cutaneous vasculitis but can be difficult for systemic types because of limited access. There are cases where biopsy samples are not conclusive and repeat biopsy collection may be needed to confirm or completely rule out vasculitis.

Treatment and Management of Vasculitis in Dogs

Treatment of vasculitis will depend on the underlying cause. However, since more than half of reported cases are considered idiopathic, the goal of the treatment for such cases will be to control the inflammatory process to reduce the damage to the blood vessel walls.

Appropriate antibacterial, anti-viral, and anti-parasitic medications are needed for canine vasculitis that is secondary to infectious causes. For immune-mediated and idiopathic cases, systemic anti-inflammatory drugs will help control inflammation of the blood vessel wall lining.

Severe cases of cutaneous vasculitis will require strong immunosuppressive medications such as corticosteroids and cyclosporine. Topical medications may help control inflammation of the skin and prevent secondary bacterial infection. Dogs with vasculitis often need long-term treatment, sometimes lifetime maintenance, to control the symptoms associated with the condition.

Diagnosis is of high importance in treating vasculitis in canines. If you suspect that your dog may be suffering from vasculitis, it’s best to visit your local vet for a complete work-up.

Read more:

Tick Talk - Dogs and Tick Control

Deworming Your Dog - Q&A

How to Examine Your Pet at Home: A Step-By-Step Guide

Need to speak with a veterinarian regarding your dog’s skin or another condition?

Click here to schedule a video consult to speak to one of our vets. You can also download the FirstVet app from the Apple App Store and Google Play Stores.