Copper storage disease (hepatic copper toxicosis) is a group of inherited and acquired conditions in which excessive copper accumulates in the liver, causing progressive hepatitis and cirrhosis. Several breeds have well-characterised hereditary forms, while environmental and dietary factors can cause acquired copper accumulation in others.
Breed Predispositions
The Bedlington Terrier has the most well-studied hereditary form — an autosomal recessive mutation in the COMMD1 gene (formerly MURR1) impairs copper export from hepatocytes. Affected dogs accumulate copper from birth, with liver disease typically apparent from 2–6 years of age. Other predisposed breeds include Labrador Retrievers, Dobermanns, West Highland White Terriers, Skye Terriers, and Dalmatians.
Pathophysiology
Copper accumulates in hepatocytes, causing oxidative stress, mitochondrial dysfunction, and progressive cell death. The resulting chronic hepatitis leads to fibrosis and, if untreated, cirrhosis and liver failure. In acute Bedlington Terrier toxicosis, massive copper release can cause haemolytic anaemia — a life-threatening emergency.
Clinical Signs
- Vomiting, lethargy, and anorexia during hepatitis episodes
- Jaundice (icteric mucous membranes and sclera)
- Abdominal distension (ascites in advanced disease)
- PU/PD (hepatic disease reduces ability to concentrate urine)
- Haemolytic crisis: sudden severe anaemia, jaundice, dark urine
- Hepatic encephalopathy in end-stage disease
Diagnosis
Liver biopsy with copper quantification is definitive. Normal hepatic copper is <400 ppm dry weight; affected dogs may accumulate >2000 ppm. Serum liver enzymes (ALT, ALP) are elevated. Ultrasound shows hepatic changes consistent with hepatitis or cirrhosis. Genetic testing is available for Bedlington Terrier copper toxicosis.
Treatment
Chelation therapy: D-penicillamine binds copper and promotes renal excretion — long-term therapy in affected dogs. Trientine and ammonium tetrathiomolybdate are alternatives.
Zinc supplementation: Competes with copper absorption in the gut — used as maintenance prevention in genetically affected dogs. Must be dosed carefully to avoid zinc toxicity.
Low-copper diet: Avoiding organ meats, shellfish, and commercial foods high in copper; commercial liver disease diets are formulated for copper restriction.
Anti-inflammatory therapy: Ursodeoxycholic acid provides hepatoprotective and anti-inflammatory effects.
Breeding and Welfare Prevention
Genetic testing and responsible breeding practices are essential for Bedlington Terrier welfare. Dogs should be tested before breeding; carriers (heterozygotes) produce affected offspring when mated to another carrier. Breed clubs should enforce mandatory testing, and breed registries should support testing programmes. Prevention through genetics testing is far preferable to management of established disease.