Feline inflammatory liver disease
Most disorders of the feline liver are loosed together under the term feline inflammatory liver disease (FILD).
Feline inflammatory liver disease encompasses:
- Cholangitis (cholangiohepatitis) - inflammation/infection of the bile duct, thought to be due to enteric bacteria (esp. Helicobacter spp and Bartonella spp) ascending the bile ducts via the sphincter of Oddi.
- - Neutrophilic cholangitis (suppurative or exudative cholangitis/cholangiohepatitis)
- - Lymphocytic cholangitis - (LCC) - (lymphocytic cholangitis/cholangiohepatitis, lymphocytic portal hepatitis or non-suppurative cholangitis)
- - Chronic cholangitis associated with liver flukes (Platynosomum spp, Opisthorchis felineus, Parametorchius complexus, Eurytrema procyonis)
- Cholecystitis - inflammation of the gall bladder (due to bacteria, choleliths, parasites)
- Extrahepatic bile duct obstruction - gall stones resulting in biliary obstruction
- Hepatic lymphoma - less common than other forms of lymphoma
- Hepatic lipidosis - predisposition in obese anorexic cats
- Triaditis - cholangitis, pancreatitis and hepatitis, often due to inflammation of the common duodenal papilla, where the bile duct and pancreatic duct meet (see figure on right). Rare cases of congenital bile duct atresia have also been reported.
- Hepatic cirrhosis
- Bile duct carcinoma
There appears to be a manifold number of causes which trigger feline inflammatory liver disease, including bacterial infections, toxins, xenobiotics, immune-mediated responses, but invariably the end result is acute hepatic inflammation and compromise, often leading to inappetance, vomiting and jaundice. The liver is primarily exposed to toxic agents via the portal blood supply which drains the intestines, and this venous blood contains small numbers of bacteria, food-derived antigens and metabolites which act as potential haptens or neoantigens with the local immune system of the liver (e.g. gut-associated lymphoid tissue (GALT)). The liver's capacity to eliminate possible toxins and insults depends on an innate defense system which includes Macrophages, natural killer T-cells, CD3+ T cells, endothelial cells and Kupffer cells within the liver, and the flushing mechanism of the biliary excretion system.
Diagnosis of hepatitis usually requires supportive tests such as liver function test. Pancreatitis is a common sequel to cholecystitis, due to the intimate relationship between bile duct and pancreatic duct
Treatment of feline inflammatory disease is based on ruling out the cause(s) and addressing these appropriately. Broad-spectrum antimicrobial therapy, anti-inflammatory agents and supportive drugs are recommended in most cases.
Parenteral clindamycin or metronidazole given orally for 2-4 weeks is usually recommended. Because biliary disease can be painful, most cats should received analgesic therapy as well. Combinations of morphine, lignocaine and ketamine (MLK) are recommended by some authors (Hitt, 2010).
Nutritional support is recommended and low protein commercial food such as Royal Canin Renal Diet provides caloric needs while restricting protein intake. Treatment in LCC is often life-long, with a variable prognosis.
- Greiter-White, A et al (2008) Association of Helicobacter with cholangiohepatitis in cats. J Vet Intern Med 20:822
- Breitschwerdt, EB (2008) Feline bartonellosis and cat scratch disease. Vet Immunol Immunopathol 123:167
- Hitt, ME (2010) Inflammatory liver diseases. In August, JR (Ed): Consultations in feline internal medicine. Vol 6. Elsevier Saunders, Philadelphia. pp:213
- Scherk, M (2007) Focus on feline medicine, PGFVSc Conference proceedings, University of Sydney, NSW, Australia
- Allam, R & Anders, HJ (2008) The role of innate immunity in autoimmune tissue injury. Curr Opin Rheumatol 20:538
- Twedt, DC & Armstrong, PJ (2009) Feline inflammatory liver disease. In Bonagura, JD & Twedt, DC (Eds): Current veterinary therapy. Vol 14. Saunders Elsevier, Philadelphia. pp:576