The surgeon is challenged to find the correct pressure by returning to surgery to loosen or tighten the ligature. This explains the elevated cost and threat to life. In conclusion the portal systemic shunt appears to be growing in frequency however increased clinician skill at detecting the liver-shunt has grown. Furthermore advances in technological ability to detect a liver-shunt though angiography may also be responsible for increased reports of the disease. The shunt most likely develops because a fetal duct fails to close after birth.
Symptoms vary but all result in central nervous system disorders called hepatic encephalopathy.
Puppies that fail to maintain the same growth rate as their siblings are suspect. Specifically shaped urinary crystals develop due to increased concentrations of ammonium. The degree of vessel occlusion may explain animals that are without symptoms until late in life. Small liver size coupled with bizarre neurological signs in young dogs is highly suggestive of the disease. Medical or surgical treatment isavailable however without corrective surgery an animal will eventually succumb to the disease.