Feline Eosinophilic Granuloma

Also known as:

Rodent ulcer Eosinophilic ulcer Eosinophilic plaques Eosinophilic granuloma

Description

Feline eosinophilic granuloma complex includes three types of lesions: 1)Eosinophilic ulcer which present as a well circumscribed, erythematous ulcer on the lip or oral mucosa of middle-aged cats. 2)Eosinophilic plaques which present as raised erythematous lesions on the skin of the medial thighs and abdomen. or 3)Eosinophilic granuloma which present on the posterior aspect of the rear legs of young cats and also found on the tongue, palate and oral mucosa.

Eosinophilic granulomas of the oral cavity appear as yellow/pink raised linear lesions. They can occur on the oral mucosa, hard palate mucosa, soft palate, or the base of the tongue. Cats with eosinophilic lesions of the mouth often have concurrent skin lesions.

The cause of feline eosinophilic granuloma is unknown but it has been associated with food and insect bite allergies, atopy, immunosuppression, bacteral and viral infections.

Signalment

More commonly found in young cats (2-6 years) and also more common in females than males.

Diagnosis

An ulcerated mass may be found at the base of the tongue or on the hard palate, the glossopalatine arches or anywhere else in the mouth as described above.

Clinical Signs

Depending on site of lesion can include dysphagia,halitosis and anorexia.

Laboratory tests

A peripheral blood eosinophilia may be present.

Biopsy

A deep biopsy specimen of the mass is required for a definitive diagnosis and histology reveals an eosinophilic tissue infiltrate

Treatment

Initial medical treatment is to control any ectoparasites. Secondly a diet trial and skin testing may be carried out to rule out food allergy and atopy. If there is evidence of a bacterial infection antibiotics. If the patient is refractory to the above Corticosteroid should be administered. Treatment should be tapered gradually once a response is seen then discontinued once signs have completely disappeared. Chlorambucil may also be useful in resistent cases.

Surgical excision is required for large lesions that interfere with breathing or swallowing.

Prognosis

Good but the lesion can recur.

References

• Tutt, C., Deeprose, J. and Crossley, D. (2007) BSAVA Manual of Canine and Feline Dentistry (3rd Edition) BSAVA

• Nelson, R.W. and Couto, C.G. (2009) Small Animal Internal Medicine (Fourth Edition) Mosby Elsevier

From Pathology

This is a complex of diseases affecting skin and oral cavity mainly of cat, which include:

1. Oral eosinophilic granuloma
2. Linear granuloma of skin
3. Eosinophilic plaque of skin

Clinical

• Any age, but usually young adults.
• Mainly affects lips, may also occasionally affect frenulum of tongue.
• Sometimes called "rodent ulcer "
• Not neoplastic - it is an inflammatory disease but is progressive and destructive.

• May see small plaque or becomes very infiltrative.
• In worst cases may erode away whole nose.

Pathogenesis

• Histologically lots of eosinophils, polymorphs.
• Exaggerated eosinophilic response.