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Management of hepatopathy in horses

02 March 2024
11 mins read
Volume 8 · Issue 2

Abstract

The liver plays a crucial role in metabolism, detoxification and nutrient storage. The liver's response to insult is often non-specific, with inflammation and subsequent fibrosis being the key pathological consequences. The treatment of liver disease is guided by clinical signs and biopsy findings. The aims of therapy are to support the recovery of the liver, treat the clinical signs (if present) and treat the cause of liver disease (if known). Corticosteroids are recommended first-line anti-inflammatory agents, and treatment is continued until biochemical evidence of improvement of hepatopathy is observed. Hepatic support supplements are commonly used but evidence of efficacy is lacking. This review outlines current treatment methods for hepatic disease and liver failure.

The liver is the largest organ in the body and performs a range of essential metabolic, secretory, excretory and storage roles. All nutrients and toxins that are absorbed from the gastrointestinal tract pass directly to the liver through the portal vein, and therefore the liver has a vital role in detoxification of endogenous and exogenous substances, as well as maintenance of nutritional homeostasis.

The liver's response to insult is often non-specific; inflammation and subsequent fibrosis are the key pathological consequences (Durham et al, 2003). Overall hepatic function is not impaired until more than 80% of the hepatic mass is lost (Reed et al, 2018). When considering management, there are two general case presentations: those with high liver enzyme activity (liver disease), and those with biochemical, clinical and histopathological evidence of hepatic dysfunction (liver failure). Both presentations may be acute or chronic. Identifying the underlying cause of a hepatopathy can be challenging and treatment is therefore often non-specific. The liver has the ability to regenerate, as hepatocytes will proliferate in response to acute external stimulation and upregulation of humoral factors (Reed et al, 2018). If hepatocyte loss is gradual and matches regeneration, then hepatic failure may not follow. The different aetiologies of liver disease have been discussed by UK-Vet Equine, and readers are directed to this article for more information (Tallon and McGovern, 2020a).

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