From the reading I have done, this particular type of hepatitis appears to be associated with copper storage dysfunction, though it has not been studied extensively enough in the Skye Terrier breed to understand if the increased copper content is secondary to cholestasis, or whether a malfunction in copper storage mechanisms is the primary cause of hepatitis. Regardless, definitive diagnosis requires a biopsy, and scanning with ultrasound is considered significantly less sensitive in detection of this disease. However, ultrasonography findings consistent with hepatitis (though not specifically Skye Terrier hepatitis) have been described.
Early-stage hepatitis dogs may have enlarged livers, but size is difficult to quantify and varies even in normal animals. Often the liver may have rounded margins on radiographs. Hepatitis is difficult to detect in the early stages with ultrasonography because changes are often very subtle. Initially, the liver may appear normal as the architecture is often not disrupted. As the insult to the liver worsens, the parenchyma can become diffusely hypoechoic with enhanced portal vein margins. In chronic hepatitis, the liver can become diffusely hyperechoic when compared to the spleen. As the disease progresses and the hepatitis becomes more chronic in longer-term cases, the liver becomes less heterogenous with areas of hypoechoic nodules within the hyperechoic parenchyma. This indicates fibrosis and may be accompanied eventually by a “cobblestone liver” where the surface of the liver itself, viewed in the capsular region, can have a knobby or bumpy appearance consistent with the nodular fibrosis that occurs in late-stage chronic hepatitis.
Diagnosing hepatitis is often extremely difficult due to the uniformity of the response of the liver to a variety of insults. Early screening for hepatitis should focus on subtle variations from the normal size, shape, and echogenicity of the liver in healthy animals, in particular a slight decrease in echogenicity and increase in size, and should be used with caution as some slight variations from norm are possible within individuals of a population. Ultimately, surgical biopsy and histopathology with consultation to a pathology laboratory versed in Skye Terrier hepatitis is considered the only definitive means of diagnosing this disease.
WSU CVM c/o 2021