ISSN 2398-2969      

Liver: toxic hepatitis

icanis

Introduction

  • Same as: acute hepatic disease Liver: acute disease.
  • Cause: ingestion of plant toxins, chemicals, therapeutic agents, insect envenomation.
  • Signs: non-specific; those of acute hepatitis including anorexia, lethargy, vomiting, diarrhea, jaundice.
  • Diagnosis: recognition of acute hepatic failure, history of exposure to toxin.
  • Treatment: supportive and elimination of toxin if recognized.
  • Prognosis: depends on toxin and severity of hepatic insult.

Pathogenesis

Etiology

Drugs

Chemicals

  • Arsenic Arsenic toxicity.
  • Carbon tetrachloride.
  • Chlorinated hydrocarbons.
  • Heavy metals.
  • Phosphorus.
  • Phenols.

Plant toxins

  • Mushrooms (Amanita phalloides;A. vernaMushroom poisoning.
  • Aflatoxins/mycotoxins Mycotoxicoses.
  • Blue-green algae; cyanobacteria.
  • Cycad palm seeds (Cycadaceaespp) Cycad palms.
  • Chinaberry tree (Melia azedarach).

Envenomation

Endotoxins and enterotoxins

Pathophysiology

  • Overwhelming hepatic insult → functional reserve capacity exceeded → failure to perform diverse metabolic functions → clinical signs.
  • Hepatic functional reserve large → 70% damage before capacity exhausted → peri-acinar zonal necrosis, infiltration of inflammatory cells due to toxins, living agents and metabolic disease will cause massive damage.
  • Local and systemic release of cytokines and other pro-inflammatory mediators →pyrexia, anorexia, depression.
  • Decreased production of clotting factors →bleeding tendency.
  • Inflammation of biliary system → partial obstruction to biliary flow →icterus.
  • Inadequate bile delivery to intestine → impairment of fat digestion →diarrhea.
  • Failure to maintain euglycemia →hypoglycemia Hypoglycemia.
  • Decreased production of albumin →hypoalbuminemia Hypoproteinemia.
  • Failure to detoxify ammonia and other mercaptans from intestine →hepatic encephalopathy Hepatic encephalopathy.
  • Increased resistance to blood flow through liver due to hepatocytes swelling → development of portal hypertension →ascites.
  • Portal hypertension → gastrointestinal wall congestion and edema → gastrointestinal ulceration →hematemesis and melena.

Timecourse

  • Within hours of ingestion of toxin.
  • Less than or equal to 2 weeks duration with no previous evidence of hepatobiliary disease.

Diagnosis

This article is available in full to registered subscribers

Sign up now to obtain ten tokens to view any ten Vetlexicon articles, images, sounds or videos, or Login

Treatment

This article is available in full to registered subscribers

Sign up now to obtain ten tokens to view any ten Vetlexicon articles, images, sounds or videos, or Login

Outcomes

This article is available in full to registered subscribers

Sign up now to obtain ten tokens to view any ten Vetlexicon articles, images, sounds or videos, or Login

Further Reading

Publications

Refereed papers

  • Recent references from PubMed and VetMedResource.
  • MacPhail C M, Lappin M R, Meyer D J et al (1998) Hepatocellular toxicosis associated with administration of carprofen in 21 dogs. JAVMA 212 (12), 1895-1901 PubMed.
  • Bunch S E (1993) Hepatotoxicity associated with pharmacologic agents in dogs and cats. Vet Clin North Am Small Anim Pract 23 (3), 659-670 PubMed.
  • Dayrell-Hart B, Steinberg S A, VanWinkle T J & Farnbach G C (1991) Hepatotoxicity of phenobarbital in dogs: 18 cases. JAVMA 199 (8), 1060-1066 PubMed.
  • Ortega L, Landa Garcia J I, Torres Garcia A et al (1985) Acetaminophen-induced fulminant hepatic failure in dogs. Hepatology (4), 673-676 PubMed.
  • Vogel G, Tuchweber B, Trost W & Mengs U (1984) Protection by silibinin against Amanita phalloides intoxication in beagles. Toxicol Appl Pharamacol 73 (3), 355-362 PubMed.

Other sources of information

  • Scherk M A & Center S A (2005)Toxic, Metabolic, Infectious, and Neoplastic Liver diseases.In:Textbook of Veterinary Internal Medicine. 6th end. Eds: S J Ettinger & E C Feldman. Philadephia: W B Sunders. pp 1464-1477.
  • Center S A (1996)Acute hepatic injury: hepatic necrosis and fulminant hepatic failure.In:Strombeck's Small Animal Gastroenterology. Eds: W G Guilford. Philadelphia: W B Saunders. pp 654-705.

Can’t find what you’re looking for?

We have an ever growing content library on Vetlexicon so if you ever find we haven't covered something that you need please fill in the form below and let us know!