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Ulcerative and Erosive Skin Disorders 1001

• Neoplasia: SCC, cutaneous epitheliotropic
lymphoma, mast cell tumor, paraneoplastic
VetBooks.ir • Conformational dermatoses: intertrigo, Diseases and Disorders
alopecia
pressure sores
• Iatrogenic: radiation therapy, thermal or
tissue injury
• Miscellaneous: feline plasma cell podo-
dermatitis, feline ulcerative dermatitis
with linear subepidermal fibrosis, snake
bite
Initial Database
• Patient history and physical exam are
important in the diagnostic process.
• Cytologic exam of any exudate contents
(see p. 1091): bacteria, inflammatory cells,
acantholytic keratinocytes (pemphigus),
fungal organisms, neoplastic cells
• CBC, serum biochemistry panel, and
ULCERATIVE AND EROSIVE SKIN DISORDERS Severe indolent ulcer in a cat. (Copyright Dr. Manon Paradis.) urinalysis if systemic signs are observed
Advanced or Confirmatory Testing
• The clinician should look for primary lesions DIAGNOSIS • Skin biopsies (p. 1091) for histopathologic
such as vesicles, bullae and pustules, and the exam are indicated in most cases of ulcerative
distribution of the lesions and involvement Diagnostic Overview dermatoses.
of the mucosa. This information can suggest A definitive diagnosis is required in order to • Endocrine tests and serologic exam depend
a specific group of diseases. institute the appropriate treatment regimen on suspected disease.
• Secondary lesions such as crusts are common. (p. 1452). • Coombs’ test: cold-agglutinin disease
• Exact description of the lesions varies accord- • Antinuclear antibody (ANA) test: often
ing to the underlying disease. Differential Diagnosis positive for animals with SLE
• The list of differentials is extensive. Among • Imaging, if relevant, to confirm systemic
Etiology and Pathophysiology the common conditions, consider feline disease or stage tumors
Variable, depending on underlying cause eosinophilic granuloma complex (indolent • Infectious disease testing, as appropriate
• Congenital, hereditary, and conformational ulcer, eosinophilic plaque, eosinophilic granu-
defects: for example, erosions can result from loma), bacterial skin infection (Staphylococcus TREATMENT
skin friction (e.g., intertrigo), and ulcerations sp), parasitic disorders (demodicosis), trauma
can be secondary to abnormal fragility of the (self-induced or not), immune-mediated Treatment Overview
dermoepidermal junction (e.g., epidermolysis disorders (pemphigus complex and lupus Varies considerably according to the disease. It
bullosa [EB]). erythematosus), and cutaneous neoplasia. must address the primary cause of the erosions
• Infectious diseases (bacterial, viral, parasitic, • Congenital and hereditary: idiopathic facial or ulcers.
fungal, rickettsial): some organisms infect dermatitis of Persian and Himalayan cats,
and lyse keratinocytes (e.g., herpesvirus) aplasia cutis, EB, dermatomyositis Acute and Chronic Treatment
or can cause epidermal necrosis secondary • Infectious/parasitic diseases: demodicosis, • Immunosuppressive treatments are required
to vasculitis (e.g., canine Rocky Mountain flea bite hypersensitivity, feline mosquito bite in immune-mediated diseases, whereas infec-
spotted fever) or a substantial inflammatory hypersensitivity, fly bite dermatitis; systemic tious diseases require proper antimicrobial
reaction, leading to ulcerative dermatitis. mycoses, sporotrichosis, phaeohyphomycosis, treatment.
• Immune-mediated disorders: ulcers may zygomycosis, candidiasis, dermatophyte • Antiparasitic treatments as required
follow the rupture of vesicles and bullae granuloma, pseudomycetoma, protothecosis, • Neoplastic diseases should be addressed
caused by the action of autoantibodies. pythiosis, aspergillosis; deep pyoderma, according to the type of tumor.
• Drug-induced conditions mucocutaneous pyoderma, pyotraumatic • Some patients with conformational derma-
• Self-induced lesions dermatitis; feline leukemia virus (FeLV), toses may need surgery to correct the skin
• Environmental injuries (e.g., coagulation feline cowpox, feline calicivirus (FCV), defect.
necrosis of the epidermis/dermis associated feline herpesvirus (FHV); canine Rocky • Supportive care may be required, especially
with thermal or chemical burns) Mountain spotted fever, leishmaniasis, and in animals with severe lesions or systemic
• Secondary to systemic diseases (e.g., uremia mycobacterial infection illness.
resulting from renal failure may cause oral • Immune-mediated disorders: pemphigus
ulceration) complex, bullous pemphigoid, erythema PROGNOSIS & OUTCOME
• Ischemic disorders: any dermatopathy that multiforme, toxic epidermal necrolysis,
interferes with vascular supply of the skin vasculitis, lupus erythematosus, EB acquisita, Ranges widely from good to poor, depending
can potentially cause ulcers secondary to skin cold-agglutinin disease, and uveodermato- on the primary cause
necrosis. logic syndrome
• Neoplasia: ulcerations noticed in skin tumors • Cutaneous adverse drug reactions PEARLS & CONSIDERATIONS
such as cutaneous epitheliotropic lymphoma • Self-induced lesions: pruritic dermatoses,
or squamous cell carcinoma (SCC) are psychogenic dermatoses, neuropathies Comments
usually secondary to the infiltration of the • Environmental injuries: burns, frostbites • Considering the wide range of treatments,
skin by neoplastic cells. • Systemic diseases: superficial necrolytic making a definitive diagnosis to correctly
• Idiopathic conditions dermatitis, calcinosis cutis, uremia address the disease is a wise approach, and

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