Pancreatitis is a common condition in dogs and cats. In fact, some experts believe that many cats suffer from pancreatitis that we fail to diagnose.
The pancreas is a two-part organ. It contains an endocrine (hormone-producing) portion called Islets of Langerhans and an exocrine portion that produces digestive enzymes.
“Itis” is a Latin suffix meaning inflammation. The pancreas becomes inflamed when its exocrine portion begins to produce digestive enzymes that then begin to digest the organ itself. The condition occurs most commonly when a pet eats an excessively-fatty meal, although pancreatitis can occur spontaneously with no known cause. These cases may have a genetic basis, as the patient’s ancestors frequently have also suffered from the condition.
Patients may present with vomiting, diarrhea, loss of appetite, lethargy, shock, dehydration, pain in the upper right quadrant of the abdomen or none of these signs. Pancreatitis can be one of the great imitators, because some dogs die with this disease and never even act ill. HGE, or Hemorrhagic Gastroenteritis, is a look-alike disease, although any type of digestive system upset can look just like this. Most pancreatitis patients arrive looking like “sick dogs,” and it is not until the laboratory test results return that we diagnose pancreatitis. Many dogs with the condition have a history of getting into the owners’ garbage. Garbage alone is bad enough, but when excessive quantities of fat are added to the picture, pancreatitis becomes much more likely.
What I’ve painted here is the image of the acute pancreatitis patient. These pets, with proper treatment and supportive therapy, can fully recover with no long-term effects on the organ.
However, pancreatitis doesn’t have to be acute. The chronic form of the disease can smolder for years, and it is this form that slowly eats away at the pancreas until all that is left is a mass of scar tissue. Scar tissue contracts. Over time, both the endocrine and exocrine functions of the pancreas can become inhibited or are lost altogether. These dogs and cats may be asymptomatic until so much of the pancreas is gone that insulin production is so low that they become diabetic.
When faced with a disease process in which the physical signs are so vague, it’s not surprising that the laboratory test findings can be misleading. White blood cell (WBC) count may be up, but that is true of hundreds of inflammatory diseases. Calcium levels may be low, but that is a rare finding and also nonspecific.
Two enzymes we like to look at on the chemistry profile in regard to pancreatitis are amylase and lipase. However, these, also, are very nonspecific, being found in several other organs of the body. At least if we find elevations in one or both enzymes along with clinical signs of pancreatitis, we are better encouraged that we are on the right track. Many, many cases of pancreatitis, surprisingly, don’t have elevations of either enzyme, so normal and low levels don’t rule the disease out.
Several years ago the Gastrointestinal (GI) Laboratory at Texas A&M University’s College of Veterinary Medicine produced a test, PLI, Pancreatic Lipase Immunoreactivity. Unlike the lipase test described above, which measures lipase from all organ sources, an immunoreactivity test allows laboratory personnel to measure specifically the lipase that comes only from the pancreas. When this level is elevated, the diagnosis is relatively sure, approximately an 80% correlation.
IDEXX Laboratories has developed their own variation of the test.
PLI is not always performed in cases of suspected pancreatitis because of expense. First, canine PLI and feline PLI are separate tests because the molecule is different in the two species. Second, it is not a routine part of a “panel” or group of tests; rather, it has to be added on.
Ultrasound can also be used to help diagnose pancreatitis, but, like radiography, doesn’t always tell the tale.
Treatment of pancreatitis is mostly supportive. Patients are kept NPO (nothing per os, meaning nothing by mouth) for several days while they are given fluid therapy. This allows the pancreas to stop being stimulated to release more digestive enzymes. Antiinflammatories are often used, sometimes corticosteroids. Broad-spectrum antibiotics are in order, as these pets are immunocompromised due to the stress of their condition.
Caught early, pancreatitis has a good prognosis in most cases.
See you Monday, Dr. Randolph.