Part III
TESTING:
There are several Test that can be used to determine if more invasive test are warranted but it is unrealistic to test every puppy or Adult dog unless some signs or symptoms are seen that justify the testing to be done.
The simple test are inconclusive at best and there are no test at this time other than the invasive ones that can give an accurate diagnosis.
There are many many problems that can lead to liver dysfunction and some are not genetic so it's not as simple as to say to test every puppy for liver shunt because the test are not always accurate and they do not do a conclusive diagnosis of liver shunt but as to a liver dysfunction.. We all wish it was as simple as testing every puppy but it just isn't that simple. 28% of test to date have shown to be inaccurate for the diagnosis of liver shunt. Not very good odds when your condemning a puppy to more invasive measures or being put to sleep due to the cost of the more invasive treatments.
There has also been a concern as to using the inconclusive test on Yorkies since Yorkies have been found to NOT have a determined consistent acid bile level even in healthy unaffected specimens.
Bile Acid Test - Serum Bile Acids - A Liver FUNCTION test, not an enzyme test. Performed by taking a blood sample, givng a meal, taking another blood sample 2 hour after the meal. The sample are then compared giving us an accurate measure of liver function. This does NOT give a CONCLUSIVE diagnosis of liver shunt only a reading of liver function. More invasive test would be needed for any diagnosis as to the liver problem.
Urine Acid Test - Ammonia tolerance testing - A urine test to determine existance of lvier disease. Could result in finding annomium biurate crystals. Not always accurate. More invasive test would be needed for any diagnosis as to the liver problem.
Blood Ammonia Value Test - Sensitive indicators: less reliable than Total Serum Bile acids because of analytic problems.
STOOL SAMPLE: A dog that has abnormal pigmented stool could indicate liver disease. Obstruction of the biliary system and normal bile pigments are not secreted to cause the normal dark color of stool.
X-Rays - An enlarged liver on a radiograph is called hepatomegaly, an abnormally small one is called microphepatica. Both be signs of a liver problem.
Ultrasounds - Is highly beneficial in the diagnosis of liver disease. Ultrasounds are usually used after the Enzyme or Bile Acid Test prior to Imaging or Biopsy. Is unreliable at best.
Liver Imaging: RADIOGRAPHY - Invasive - A dye is injected into the spleen and the dye is tracked through Radiograph through the blood vessels. A blood vessel bypassing the liver can easily be seen on the image. This is the only universally accepted method of confirming a shunt, short of major surgery, it however is extremely invasive and is a poor choice for "screening" purposes.
Liver Biopsy - Extremely Invasive - A valuable test in the diagnosis of liver disease. A sample of the liver is obtained during exploratory surgery. Can be life-threatening if the diseased liver hemorrhages into the abdomen so a coagulation panel prior to any liver biopsy is necessary.
INVASIVE SURGERY and AUTOPSY are the only two that can positively identify a LIVER SHUNT.
Also keep in mind that Liver Shunt has to this date not been proven to be genetic. No genetic markers to date have been found and no research has proven that it is genetic. However there is every logical reason to believe that SOME FORMS are genetic.
Other Liver Dysfunctions that could mimic Liver Shunt:
Acute Hepatic Failure - Rapid loss of liver function due to death of liver cells caused by drugs, toxins, infectious diseases and lack of oxygen. Mimics Liver Shunt signs and symptoms.
Hepatic Lipidosis - The accumulation of fatty tissue within the liver caused by appetite loss which promotes the accumulation of lipid in the liver. Mimics Liver Shunt signs and symptoms.
Hepatitis Chronic Active - Inflammation of the liver causing the accumulation of inflammatory cells and scarring. Mimics Liver Shunt signs and symptoms.
Copper Storage Disease - Genetic disease caused by excessive accumulation of copper in the liver. Mimics Liver Shunt signs and symptoms.
Infectious Hepatitis: Viral disease that targets the liver, kidneys, eyes and blood stream. Mimics Liver Shunt signs and symptoms.
Benign Tumors: Abnormal cell accumulation that affects the livers ability to filter and process properly. Mimics Liver Shunt signs and symptoms.
Cancer: Abnormal cell accumulation that affects the livers ability to filter and process properly. Mimics Liver Shunt signs and symptoms.
Toxins: Excessive overload of impurities in the blood stream that overloads the livers ability to filter and process properly due to illness or disease. Mimics Liver Shunt signs and symptoms.
Parasites: Such as liver flukes or HEARTWORMS which invade the liver causing the livers inability to filter and process properly. Mimics Liver Shunt signs and symptoms.
Liver Abscess: Lesions that cause the livers inability to filter and process properly. Mimics Liver Shunt signs and symptoms.
Cirrhosis - One form of the end stage of liver disease causing the liver to be unable to filter and process properly. Mimics Liver Shunt signs and symptoms.
Trauma - Severe or blunt blow to the liver region causing contusions. Mimics Liver Shunt signs and symptoms.
Pancreatitis - A severe inflammatory process that occurs with digestive enzymes that can spill over into the liver and cause severe disease. Mimics Liver Shunt signs and symptoms.
ADVENOVIRUS - Viral disease of canines. Mimics Liver Shunt signs and symptoms.
POISONS: Toxic substances ingested by mouth or absorbed through the skin into the blood stream that can have deadly consequences to your animal such as Oleander, Azalea, Rhododendrons, Poinsettias and Japanese yews to name a few. Causes liver malfunction and can mimic Liver Shunt signs and symptoms.
MEDICINES: There are several chemicals that could be toxic to the liver including medicine given daily to many animals such as Rimadyl (arthritis treatment), Thiacetarsamide (heartworm treatment), Ketaconazole (fungal treatment), Tylenol (acetaminophen), Glucocorticoids (cortisone), Anthelmintics (wormer), Parasiticides, Phenobarbital (epilepsy meds).
So it seems that some times we're danged if we do and danged if we don't!!!!!!!!!!
What age is Liver Shunt Diagnosed:
Liver Shunt can be diagnosed as early as 8 weeks of age and for years after that. The degree of the shunt determines at which stage the diagnosis is usually made. A minor shunt where only minor amounts of blood are being redirected around the liver may go for years without being diagnosed.
The amount of protein that you feed your animal also has some bearing as to the degree of problems that your animal will exhibit thus delaying the diagnosis further if you are feeding a low-protein feed.
Keep in mind also that other disease or occurrences can cause Liver Shunt which would make it diagnosed only after the disease or occurrence.
IN CLOSING:
Yes, liver shunt is a concern in Yorkies. Liver Shunt may or may not be genetic but everything leads us to believe that it CAN BE. Liver Shunt can however be caused by other outside sources and other medical ailments.
There are NO "SCREENING" methods at this time by which to screen every puppy that is considered to be accurate or justified.
There is no shame in producing a liver shunt puppy - the shame is not taking the first step to prevent it in the future |