Companion Animals

Cat Portosystemic Shunts: Diagnosis and Treatment

Portosystemic shunts are abnormal blood vessel connections that bypass the liver in cats, causing neurological signs and requiring surgical or medical management.

Key Facts

Congenital portosystemic shunts are present from birth and may be intra- or extrahepatic
Cats with shunts may show neurological signs (hepatic encephalopathy), poor growth, and urinary crystals
Diagnosis requires ultrasound, CT angiography, or nuclear scintigraphy
Surgical ligation of the shunt can be curative in extrahepatic cases
Medical management with lactulose, antibiotics, and dietary protein restriction may control signs

Welfare Considerations

Hepatic encephalopathy causes episodes of confusion, aimless wandering, seizures, and blindness, representing significant suffering. Cats affected from birth may never develop normally. Successful surgical correction dramatically improves quality of life. Medical management controls signs but does not address the underlying abnormality. The welfare impact of repeated episodes of encephalopathy warrants active treatment rather than watchful waiting.

What You Can Do

Seek veterinary evaluation promptly if a kitten shows neurological signs, poor growth, or urinary symptoms
Pursue CT angiography for definitive shunt mapping before surgical planning
Feed appropriate low-protein prescription diets as recommended
Give lactulose and antibiotics as prescribed to prevent encephalopathy
Discuss specialist surgical referral for cases where surgery is an option