What Are Liver Flukes?
Liver flukes are flatworm parasites that infect the liver and bile ducts of animals, including cats. They cause inflammation, tissue damage, and can lead to severe liver and bile duct disease. The most common liver fluke in the U.S. is Platynosomum fastosum, also known as the cause of “lizard poisoning” in cats.
Types of Liver Flukes in Cats
- Platynosomum fastosum: Found in warm, tropical regions like Florida and Hawaii. Cats get infected by eating lizards or frogs.
- Opisthorchis felinus: Found in Europe, Russia, and Asia. Cats get infected by eating raw fish.
- Clonorchis sinensis: Known as the oriental liver fluke, found in Asia.
- Metorchis orientalis/conjunctus: Found in North America, Europe, Russia, and China.
- Eurytrema procyonis: Mainly affects raccoons and foxes but can infect cats.
Causes of Liver Flukes
Cats become infected by eating intermediate hosts (e.g., lizards, frogs, or fish) that carry the parasite’s infective stage (metacercariae). The parasite’s life cycle involves snails as the first intermediate host and other animals as the second.
Symptoms of Liver Flukes
- Early stages: Mild weight loss, poor appetite, diarrhea, lethargy, and fever.
- Advanced stages: Severe liver and bile duct disease, including jaundice, vomiting, abdominal distension, and anorexia. Untreated cases can be fatal.
Diagnosis
- Fecal Testing: Special techniques are needed to detect fluke eggs, but shedding is intermittent.
- Blood Testing: Elevated liver enzymes (ALT, ALP), bilirubin, and eosinophils may indicate infection.
- Imaging: Ultrasound can reveal bile duct and gallbladder changes.
Treatment
- Praziquantel: Effective for Platynosomum fastosum infections.
- Fenbendazole: Used for other fluke infections.
- Supportive Care: Fluids, nutritional support, antibiotics, and anti-inflammatory medications may be needed for severe cases.
Prevention
- Keep cats indoors to prevent hunting of intermediate hosts.
- Regular fecal testing and empirical treatment with praziquantel may be considered in high-risk areas.
Key Takeaways
- Liver flukes are a significant concern in tropical and subtropical regions.
- Cats that hunt lizards, frogs, or fish are at higher risk.
- Early diagnosis and treatment are crucial to prevent severe liver damage.
- Preventative measures, like keeping cats indoors, can reduce the risk of infection.
If you suspect your cat may have liver flukes, consult your veterinarian for appropriate testing and treatment.