Cutaneous Vasculitis In Dogs

Cutaneous vasculitis is used to describe a heterogeneous group of skin diseases that are caused by inflammation of the small- or medium-sized blood vessels such as capillaries, arterioles, postcapillary venules, etc. This condition can be immunological, non-immunological, idiopathic, or eosinophilic.

While vasculitis can affect any region of the body, the primary target is often the skin and may be a sign of the possibility of internal disease. Cutaneous vasculitis most commonly affects the skin over distal extremities and over pressure points such as the pinnae, footpads, scrotum, and tail. True vasculitis often causes ulceration and epidermal necrosis, and dogs are frequently systemically unwell.

Vasculitis affecting the smaller blood vessels tends to cause lesions such as shallow ulcers, petechiae, and purpura. Less commonly, vasculitis affecting large or medium, or deeper vessels causes deep ulcers, nodules, and Livedo reticularis.

Many terms used to describe cutaneous vasculitis overlap and are used consistently in the literature:

• Cutaneous vasculitis: Vasculitis affects the skin but not the internal organs.
• Cutaneous small-vessel vasculitis (CSVV): This type of vasculitis also affects the small vessels of the skin but not the internal organs.
• idiopathic cutaneous small-vessel vasculitis: CSVV refers to small-vessel vasculitis of unknown cause.
• Hypersensitivity vasculitis: Hypersensitivity vasculitis refers to CSVV that is caused by an infection or drug usage.
• Leukocytoclastic vasculitis: Immune complex-mediated vasculitis consists initially of neutrophils, which after degranulation result in deposition of leukocytoclasis (nuclear debris) in the vessel wall.

Early signs:

• Purpura
• Oedema
• Ecchymosis
• Purpura

Advanced stage:

• Crusting
• Scaling
• Erosions
• Hyperpigmentation
• Alopecia
• Ulcerations
• Scarring

Systemic signs:

• Fever
• Lethargy
• Anorexia
• Joint pain
• Lymphadenopathy

Control of the induction (affector) part of the immune response:

This is focused on the suppression of the aberrant responses of the dog's immune system that is liable for the production of antibodies or cytokines directed against normal tissue.

Examples –

• Corticosteroids like oral prednisone or methylprednisolone.
• Alternative steroids for prednisone- and methylprednisolone-refractory cases include dexamethasone and triamcinolone.
• Immunosuppressive drugs, such as cyclosporine, azathioprine, or chlorambucil.
• Nonsteroidal immunosuppressive drugs include tetracycline/niacinamide and gold salts.

Control the inflammation (effector phase) and/or maintenance period:

Once induction is reached, medications are tapered gradually and treatment is more focused on maintenance of equilibrium state and control of inflammation. In many situations, however, autoimmune disease is treated on an outpatient basis.

1. It is best to avoid the allergens altogether. Pollens and dust (use an air cleaner with a HEPA filter), Molds (place activated charcoal above the exposed dirt in your house plants or use a dehumidifier).
2. Medicated baths: Medicated baths (weekly or every other week) with medicated shampoos and antimicrobial and antifungal agents relieves injured skin and remove allergens that cause skin allergy flare-ups. Afterward, apply a rinse to prevent drying out of the skin and hair coat.
3. Dogs with skin folds can be cleaned daily with a clean, damp cloth, shampoo, wipes, ointment, lotion, spray, skin cleanser, etc.
4. Regularly brush the dog to reduce shedding. Consistent grooming spreads the skin’s natural protective oils across the surface.

• There is no means of preventing or avoiding vasculitis save genetic counseling.
• Screening of highly affected breeds prior to breeding is strongly recommended.
• Never skip check-ups.
• Feed a home-prepared diet of pasture-fed, organically produced ingredients.
• When your dog has been prescribed a dosage, taper off slowly or else you might experience withdrawal symptoms.

German Shepherd, Saint Bernard, Jack Russell Terrier, Greyhound, Shar Pei, Bichon Frise, Maltese, Pekingese, Poodle, Yorkshire Terrier

1. Causes:

• Mostly congenital/ idiopathic
• Allergic skin diseases (e.g., flea allergy dermatitis, atopic dermatitis)
• Infections (bacterial, fungal, Viral -Coronavirus, Parvovirus)
• Protozoan (Sarcocystis, Leishmania)
• Rickettsia (Rickettsia, Ehrlichia, Babesia, Anaplasma)
• Reported drugs associated with PF include antibiotics (e.g., sulfonamides, penicillins, cephalosporins)
• Topical ectoparasitic preparations containing fipronil, metaflumizone, amitraz, dinotefuran, S-methoprene, permethrin, or pyriproxyfen
• Concurrent systemic disease (e.g., cutaneous polyautoimmunity with simultaneous PF)

2. Types:

Immunological vasculitis: This involves type III hypersensitivity response and the deposition of immune complexes in the walls of blood vessels which in turn cascades the employment of inflammatory cells to the region. The type III hypersensitivity response is triggered by infectious agents, drugs, vaccines, neoplasia, and food additives.

Eosinophilic vasculitis: Type I hypersensitivity response affects the submucosal capillaries and venules. Ex., arthropod bite lesions.

Non-immunological vasculitis: When the endothelial cells are damaged by physical blockage of blood vessels, burns, or trauma affecting the blood flow hemodynamics.

Idiopathic vasculitis: Several breeds are predisposed to vasculitis, where the pathogenesis is not fully understood.

3. Mortality:

Cutaneous vasculitis is not a potentially life-threatening disease in dogs and the mortality rate of dogs is not documented.

4. Diagnosis:

• Routine hematology
• Urinalysis
• Surgical biopsy
• histopathological examination of the skin
• Rickettsial screening
• Fungal culture
• Bacterial culture

5. Prognosis:

Depending on the cause and any underlying condition, the prognosis varies ranging from fair to guarded. Dogs that have only a single episode of vasculitis has an excellent prognosis, on the other hand, in genetically predisposed dogs, the lesions tend to relapse after treatment.

Time to visit the vet clinic for an examination, if you notice any of the following:

• Open sores
• Fluid-filled blisters
• Itchy Skin erosions and crusts

• Choose a wholesome food, minimally-processed, that is free of preservatives, chemicals, hormones, and other toxic additives. Keep away from butylated hydroxyanisole (BHA) and ethoxyquin.
• An allergen-free (hypoallergenic) balanced diet (check for thickeners, coatings, flavors).
• Try an elimination diet after food sensitivity testing. Many prescribed medications for an autoimmune disease can cause GI and non-GI woes.
• Consider a diet with all essential nutrients and also provides plenty of antioxidants (combat free radicals).
• Consider a probiotic supplement with added support for the liver.

In general, Most dogs with vasculitis conditions can be satisfactorily treated. Only in genetically predisposed dogs, it is usually a lifelong condition requiring continuous management.

After immunosuppressive therapy is tapered and discontinued, some dogs may remain in remission and they require lifelong therapy to control remission.