Gastritis, Chronic

Description

Chronic gastritis is often characterised by persistent vomiting of variable frequency and appearance. The underlying cause is unknown but chronic gastritis can be classified into one of four types according to its histological appearance.

1)Lymphocytic-plasmacytic gastritis which may be an immune response to numerous antigens. Helicobacter felis has been suggested as a cause for such a reaction in dogs and cats.

2)Eosinophilic gastritis which may result from an allergic reaction to food antigens.

3)Atrophic gastritis which is thought to result from an immune reaction and/or chronic gastric inflammation.

4)Granulomatous gastritis which may be caused by Ollulanus tricuspis in cats.

Signalment

Can affect both dogs and cats.

Diagnosis

Clinical Signs

Include anorexia, vomiting (frequency is very variable from once weekly to several times each day. May also present with haematemesis)and emaciation with longstanding disease. Sometimes dehydration is also present.

Laboratory Tests

Clinical pathology findings are not diagnostic of chronic gastritis. On Haematology and biochemistry an anaemia due to chronic blood loss may be present, hypoproteinaemia due to protein loss from the stomach, electrolyte imbalance due to electrolyte loss in the vomitus, peripheral eosinophilia may be present with eosinophilic gastritis. Assess for signs of renal and hepatic disease as potential systemic causes of persistent chronic vomiting.

Radiography

Plain abdominal radiography is usually unremarkable. Contrast radiography may reveal thickening or irregularity of the gastric rugae.

Biopsy

Biopsy of the stomach followed by histological examination should always be performed and are required for a definitive diagnosis. They should be taken via endoscopy as this is less invasive than via surgery.

Endoscopy

Gastroscopy can be used to visualise the gastric mucosa. Varying degrees of hyperaemia, hypertrophy and haemorrhage may be evident. However, if no endoscopic lesions are visualised, chronic gastritis cannot be ruled out.

Treatment

General Approach

Removal of the underlying cause should be the aim. Elimination diet in cases where lesions are infiltrated with eosinophils, plasma cells or lymphocytes as determined via biopsy as this may reflect a hypersensitivity to dietary protein. This may include feeding a homemade or veterinary restricted-protein or hypoallergenic diet.

Lymphocytic-plasmacytic gastritis

May resond to dietary therapy alone. Gastroprotectants such as sucralfate and cimetidine may be beneficial. corticosteroids can be used in moderate-severe cases as a means of immunomodulation. Azathioprine may be used in conjunction with corticosteroids in cases that fail to respond to corticosteroids alone. The white cell count should be monitored from 2 weeks after the first dose and treatment should be stopped if the count falls to less than 4x10e9/L.

Eosinophilic gastritis

A strict elimination diet is often successful, the addition of corticosteroid therapy may be required in cases that do not respond to dietary therapy alone. Azathioprine can be used in addition in those cases that fail to respond. gastroprotectant administration should be routine.

Atrophic gastritis

Is more difficult to treat than lymphocytic-plasmacytic or eosinophilic gastritis, diets low in fat and fibre may help to control signs. corticosteroids are thought to be beneficial as it is thought that the disease is immune-mediated.gastroprotectants are advised. Additionally prokinetics may be used to empty the stomach.

Granulomatous gastritis

This is difficult to treat. It does not respond well to diet or corticosteroid therapy.

Prognosis

Depends on the type of gastritis, Lymphocytic-plasmacytic gastritis and Canine eosinophilic gastritis have a good prognosis with approprate therapy. Feline eosinophilic gastritis has a Poor prognosis.

References

• Hall, E.J, Simpson, J.W. and Thomas, D. (2005) BSAVA Manual of Canine and Feline Gastroenterology (1st Edition) BSAVA

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

From pathology

• Chronic gastritis is usually proliferative rather any other type of gastric inflammation.
• Usually a parasitic cause.
• Occurs mostly in the pig and in cattle.

• Pig
  • Redworms (Hyostrongylus rubidis)
  • Seen mostly in sows, and are present in up to 30% of pig herds.
  • Small numbers produce little pathology, but large numbers cause thin sow syndrome.
    • Animals eat well but slowly lose condition.

• Cattle
  • Ostertagiasis produces a condition similar to thin sow syndrome.