Lymphangiectasia

Signalment

Breed predisposition:
- Yorkshire Terrier
- Lundehund
- Rottweiler
- Soft Coated Wheaten Terriers

Description

Lymphangiectasia is characterised by dilation and dysfunction of the lymphatic vessels of the intestines. Consequently, protein rich lymph leaks into the intestinal lumen, causing a protein-losing enteropathy and severe lipid malabsorption. It is relatively common in dogs but rare in cats.

Lymphangiectasia can be classified as primary or secondary. Primary lymphangiectasia may form part of of a localised or a more widespread lymphatic abnormality. Secondary lymphangiectasia is the result of lymphatic obstruction. The obstruction may be caused by:

inflammation, neoplastic infiltration o fibrosis
thoracic duct obstruction
right sided cardiac failure
caval obstruction
hepatic disease

Lymphagiectasia often accompanies a lipogranulomatous inflammation, but it is not clear which is the primary event. Lymphangitis can cause lymphatic obstruction but the leakage of lymph can cause a granuloma to form.

Diagnosis

Clinical Signs

Weight loss
Chronic diarrhoea, steatorrhoea
Ascites, oedema or chylothorax may result if there is severe hypoproteinaemia or lymphatic obstruction
Increased appetite
Vomiting, lethargy and anorexia (less common)

Laboratory Tests

Haematology

Panhypoproteinaemia
Lymphopaenia

Biochemistry

Hypocholesterolaemia
Hypocalcaemia due to hypoproteinaemia, vitamin D and calcium malabsorption
Hypomagnesaemia

Other Tests

Faeacal α1-proteinase inhibitor concentrations may be used to confirm protein-losing enteropathy

Diagnostic Imaging

Abdominal ultrasonography may reveal pleural fluid or ascites as well as help to narrow down other differential diagnoses. Mucosa of intestinal loops may appear thickened due to oedema.

Histopathology

Treatment

Prognosis

References

Ettinger, S.J. and Feldman, E. C. (2000) Textbook of Veterinary Internal Medicine Diseases of the Dog and Cat Volume 2 (Fifth Edition) W.B. Saunders Company.
Hall, E.J, Simpson, J.W. and Williams, D.A. (2005) BSAVA Manual of Canine and Feline Gastroenterology (2nd Edition) BSAVA
Nelson, R.W. and Couto, C.G. (2009) Small Animal Internal Medicine (Fourth Edition) Mosby Elsevier.