“This shot should stop the vomiting,” I said confidently, syringe in hand. The little West Highland white terrier had been throwing up all day. Despite my recent column about the imprudence of assuming every vomiting dog has “nonspecific gastroenteritis”(that is, mild, usually self-limiting disease), I didn’t push for diagnostic tests that first visit. I often hesitate to recommend the expense of such testing on every barfing pup when I know odds are high the pet in question will be better the next morning.
“Withhold food and water,” I continued. “We’ll give subcutaneous fluids before you go, so he doesn’t get dehydrated.” We gave detailed instructions about how to gradually reintroduce food and water as Westie got better, and sent them home. But the next day, Westie wasn’t better. In fact, he was much worse. Lethargic. Not eating. Thinking about my Christmas Eve dog with an acorn lodged in his intestines, we took radiographs. Westie’s liver was slightly enlarged, but there was no evidence of a foreign body, tumor, obstruction, or other abnormality. Next came blood tests we could run immediately right here in my clinic.
Pancreatitis. The pancreas is an organ that lies along the intestines, stomach, and liver. Its primary job is to secrete enzymes that help with digestion, and insulin, which regulates blood glucose. The word pancreatitis simply means that the pancreas is inflamed. It doesn’t explain why. Sometimes there is a history of the patient eating a fatty meal prior to the onset, but often there is simply no explanation for the inflammation. It is thought that certain drugs, such as phenobarbital, may predispose a dog to pancreatitis, as can underlying disorders such as Cushing’s disease and hypothyroidism. Breed may play a role. Terriers and miniature Schnauzers may be at higher risk … but the reality is that in most cases, we don’t know why it occurs.
Canine pancreatitis can be acute or chronic, mild to severe. It frequently occurs concurrently with other diseases such as gastroenteritis, inflammatory bowel disease, or kidney failure. Symptoms may include loss of appetite, dehydration, lethargy, vomiting, fever, abdominal pain, jaundice, diarrhea, and increased respiratory rate. Any age or sex can be affected. Years ago, we were taught we could diagnose pancreatitis based on elevations of two pancreatic enzymes, called lipase and amylase, but nowadays we know other diseases can cause these elevations as well. Conversely, in some cases of pancreatitis, these enzymes can be normal. Other tests done at large reference laboratories can help evaluate pancreatic function, as can ultrasound, but ultimately, short of biopsy, there is no single test that proves definitively that a dog has this condition. We make the diagnosis by putting together many little pieces of the puzzle including history, clinical signs, and consistent lab results.
Westie’s lipase and amylase levels were sky-high. He had almost all the clinical symptoms listed. There was no history of a fatty meal, but he was a terrier, putting him in the high-risk category. Everything fit a presumptive diagnosis of acute pancreatitis. And there was one more problem. His blood sugar was extraordinarily high, more than six times normal. His pancreas had stopped producing insulin, leading to diabetes. And not just straightforward diabetes (which is tricky enough). Westie’s diabetes was now causing either diabetic ketoacidosis or hyperosmolar nonketotic syndrome — medical emergencies in which extremely high blood sugar, combined with inadequate insulin, leads to potentially fatal illness.
The complications and interactions of all of these systems are too intricate to explain here. Although the prognosis for simple pancreatitis is fair, it can be life-threatening. Add the extreme disruption of normal metabolism from the profound diabetes, and Westie was in grave danger. I offered to send him off-Island for round-the-clock intensive care and the input of specialists smarter than me. No kidding. I’m pretty good at diagnostics and managing complex medical cases, but Westie’s situation was daunting — a labyrinth of physiological interactions. When his owner declined the referral, I reiterated my limitations of equipment, staff, and expertise, but agreed to try my best. I called an internal medicine specialist for advice. Was the diabetes a result of the pancreatitis, or the other way around? Was his labored breathing from pain, acid-base imbalance, pleural effusion, pulmonary edema, or even a pulmonary embolism? How fast could I give intravenous fluids?
There is no specific treatment for pancreatitis. Simple cases are treated with intravenous fluids and withholding food and water. Medications to control pain and vomiting are added as needed. But we also had to lower Westie’s blood sugar and address the other metabolic abnormalities. Whether the pancreas would eventually regain normal function, I just didn’t know. The diabetes might resolve as the pancreatitis resolved, or might be permanent, requiring lifelong insulin injections. There might be some other serious disease underlying the whole episode that we had yet to determine. As glucose levels came down, we had to monitor potassium and phosphorus levels closely. As we gave intravenous fluids, we had to watch for fluid overload. One thing getting better could make another thing worse. Too much. Too little. Everything was potentially life-threatening.
Sweet Westie and I got to know each other well. When hours of intravenous fluids didn’t reduce his blood sugar sufficiently, we started insulin injections. He would improve for a few hours, holding his head up and looking around, but then his sugar would spike again and he would feel terrible. He eventually lapped a little water and held it down, but had no interest in food. His pain was increasing, despite repeated analgesic injections. After two days of intensive treatment, we were unable to turn the tide. Continuing to decline, he was clearly suffering. The decision was made to let him go.
Blood tests at the first visit would not have led to a different outcome: Westie’s illness was swift and deadly. Still, it’s a cautionary tale. Playing the odds can never really take the place of doing diagnostic testing if we want to know exactly what is going on medically.