- Results due to exposure to chemicals (not immunologic reaction)
- Acids, alkali, detergents, irritant plants etc.
- In cats and dogs lesions usually on skin of abdomen, feet, chest, eyelids, axillae
- In horses lesions on muzzle, lower limbs, under tack
- Grossly:
- Erythematous pathes and papules
- Occasionally vesicles
- Lesions caused by self-trauma include ulcers and crusts
- Microscopically:
- Hyperplastic, spongiotic dermatitis
- Superficial perivascular inflammation
- Necrosis may be caused by corrosive substances