Cutaneous vasculitis in equines: a retrospective study of 72 cases

Abstract

Cutaneous vasculitis was identified by histopathological findings in 72 equines. The most frequent clinical findings were crusts/scales and oedema of the legs with the most common underlying disease being photo-aggravated dermatitis. Common laboratory findings were anaemia, neutrophilia, hyperglycaemia and hyperglobulinaemia. Histopathological patterns were most commonly cell-poor and lymphocytic/histiocytic. While statistically supported treatment recommendations could not be made due to the large numbers of confounding factors, trimethoprim-sulfa antibiotics, corticosteroids, and/or resolution or control of the underlying disease process were the most common treatment modalities.

Immune-Mediated Disorders

“…* Erythema multiforme and exfoliative dermatitis ( Fig. 10,49 Unusual drug eruptions have been reported. 12,39 Vasculitis has been seen in association with phenylbutazone (see Fig.…”

“…10,49 Unusual drug eruptions have been reported. 12,49 There are anecdotal reports of rump and tail head pruritus following the administration of moxidectin. 9-50 and 9-51) following the administration of ivermectin.…”

“…* Cutaneous vasculitis most commonly is believed to be immune-mediated. 12,49 In some instances, vasculopathies are restricted to white-skinned, whitehaired areas of the distal limbs and muzzle, even when large areas of the skin may be nonpigmented, suggesting that some environmental substances (pasture plants, and so forth) are acting as photoactivated allergens (photoactivated contact dermatitis). Type I hypersensitivity reactions may be important in the initiation of immune complex deposition in blood vessel walls.…”

TREATMENT OF VASCULITIS AND DERMATITIS IN A 59-YR-OLD NILE HIPPOPOTAMUS (HIPPOPOTAMUS AMPHIBIUS)

“…Underlying causes in horses can include photoaggravated dermatitis, drug reactions, atopic dermatitis, erythema multiforme, fungal infection, and others. 12 The hippo presented in February, but had no access outdoors. Therefore, photoaggravated dermatitis was unlikely.…”

“…Histopathology in this case was consistent with vasculitis based on the presence of vascular wall necrosis, hyalinization, and inflammation, as well as luminal thrombosis, but no inciting factor was identified. 12 It is unknown if vasculitis developed first with a secondary bacterial dermatitis or vice versa.…”