The liver produces a large amount of hormones, enzymes, and performs several functions essential to life. It is also the organ responsible for cleansing of toxins from the bloodstream, by turning them into removable substances. Detoxification is essential as toxins may damage both liver cells membranes and the cell membranes of other organs. Glutathione, the main detoxifying and antioxidant agent of the liver, is essential for enhancing the removal of toxins and prevents cell damage.

The term liver disease refers to many diseases and disorders that may cause impaired liver function can make the liver a decrease of its functions. The dysfunction may be primary, but the liver is often secondarily affected by disorders of other organ systems, since it is involved in many metabolic and detoxifying processes. This is especially due to toxics agents produced by the diseases of the gastrointestinal tract.

Pathophysiology of liver diseases

Liver diseases are usually classified as follows:

• Non-infectious inflammatory liver diseases
  • Chronic hepatitis
  • Feline cholangiohepatitis complex
  • Reactive hepatopathy: due to hepatotoxic substances such as coticosteroids, NSAIDs, anticonvulsant and anti-Leishmania treatments (allopurinol).
• Infectious inflammatory liver diseases
• Abnormal cells storage
  Feline Hepatic Lipidosis
• Vascular: shunts
• Neoplasms

Most liver functions have a huge reserve capacity and a high potential for regeneration. Clinical signs appear with increased impairment and degeneration; althought signs are similar in dogs and cats, cats, usually do not present with polyuria / polydipsia or dysuria.

The symptoms may reveal signs that may indicate liver disease, but can also be due to other problems.

The most common clinical signs are:

• Ascites
• Apathy
• Anorexia
• Vomiting
• Inappetence
• Diarrhea
• Weight loss
• Polyuria / polydipsia
• Abdominal distension
• Jaundice
• Pale mucous membranes

Liver diseases usually damage liver cell structures, preventing its proper physiological functioning, and decrease toxin neutralization and excretion of system and also cell repair.

The accumulation of membranecytolitic bile acids damages liver cell membranes as they insert into lipid membranes. This damage is associated with the release of membrane enzymes such as alkaline phosphatase and GGT, as well as the induction of apoptosis. On the other hand, the accumulation of toxins due to the failure of the glutathione detoxification system accelerates the oxidative stress, the death of hepatocytes and the progression of liver disease.

Diagnosis

The diagnosis and monitoring of liver diseases usually require monitoring laboratory parameters.

Special attention must be paid to:

• Indicators of hepatocellular injury: detection of transaminases (ALT, AST, alkaline phosphatase, GGT) may indicate damage to the membranes of hepatocytes and biliary epithelium.

Liver enzymes: location and conditions associated with increased values.

Compounds Is associated with:

In order to improve monitoring, laboratory findings should be evaluated along with clinical history, physical examination and the findings from previous clinical examinations. Liver imaging and biopsy are also advisable.