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Introduction:
Pancreatitis can be seen either as an acute disease or as a chronic manifestation.
Acute disease is seen as a sudden inflammatory process of the pancreas. Acute pancreatitis, while common in the dog, is less common recognized by veterinarians in the cat. Many now believe that feline pancreatitis is frequently missed by veterinarians. Chronic pancreatitis is a continuous inflammatory process, which in turn causes irreversible morphological changes. The alteration in the pancreatic tissue may eventually lead to partial or total loss of functionality. Pancreatitis may also cause major pathophysiological changes that can lead to multiple organ system involvement (eg. impaired liver function). Chronic pancreatitis may present clinically or in subclinical form. In cats, the association of pancreatitis with concurrent hepatic and enteric disorders has been well documented and may be related to the anatomic arrangement of the pancreatic and common bile ducts. |
| Pathogenesis: The exact etiology is
unknown. Many factors are thought to contribute including, nutrition, drugs,
toxins, duct obstruction, viral parasitic, and mycoplasmal infections. A
proposed pathogenesis for pancreatitis is an instigating episode of abnormal
blood flow. Surgery, shock or ischemia due to impaired cardiovascular
function may be the initial assault, resulting in a cascade of events necessary
for pancreatitis to occur. Pancreatitis is
thought to occur when digestive enzymes are activated within the pancreas, resulting in
auto-digestion. Amplification of the digestive enzyme cascade can lead to
a severe
hemorrhagic or necrotic pancreas with multiple organ system involvement. Vasoactive
polypeptides released from the inflamed pancreas into the general circulation cause many
of the systemic manifestations associated with pancreatitis. Some examples are hepatocellular
necrosis, pulmonary edema, and disseminated intravascular coagulopathy. Variations in types and manifestations of pancreatitis exist in cats and dogs. Acute forms of pancreatitis can be seen in either necrotizing or suppurative forms. Other more chronic forms are intestinal pancreatitis. Chronic mild interstitial pancreatitis and cholangiohepatitis have been associated frequently together (possible due to the anatomical proximity of the biliary and hepatic ducts). Thus, a relationship between pancreatitis and other systemic disease can be seen. |
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Acute Hemorrhagic Pancreatitis http://www.bcnr.moph.go.th/webpath/panchtml/panc049.htm |
Gross Pathology:
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Histopathology:
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Species affected: Although the lesion has been described in a variety of species, pancreatitis is primarily a problem in dogs and, to a somewhat lesser extent, cats. Signalment: Can affect any age and both sexes. Obese dogs and dogs fed high fat diets or a fatty meal are thought to be at higher risk. In cats, the age of affected animals is also variable.. |
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Presenting clinical signs: Presenting clinical
signs are nonspecific and variable depending upon the stage of illness. Signs range
from anorexia, lethargy, weight loss, hypothermia, depression, and mild abdominal
discomfort to severe vomiting, hemorrhagic diarrhea, shock and death in acutely ill
animals. Cats are sometimes icteric upon presentation. These cats are often
dehydrated and anemic, though the anemia may be masked by an elevated PCV due to the
dehydration. The hematocrit should be evaluated carefully to determine if the
patient is truly anemic.
Clinical Findings:
Dehydration marked by a high PCV and TP, and a moderate non-regenerative anemia.
BUN and creatinine are usually elevated (pre-renal azotemia).
Hyperglycemia (from release of glucagon from the endocrine pancreas due to inflammation and stress).
Hypoalbuminemia may be seen from vascular and peritoneal loss.
High serum alanine amino transferase (ALT) ranging from normal to 18x normal, and high serum alkaline phosphatase (AP) increased 2-17x normal.
Hyperbilirubinemia may be seen.
Amylase and lipase levels are not reliable markers for feline pancreatitis. Trypsin-like immunoreactivity (TLI) is thought by some to be a more useful tool in the evaluation of pancreatitis in cats. However, a recent study indicates TLI may be as unreliable as amylase and lipase reflecting the difficulty in diagnosing pancreatitis in the cat.
New developments in diagnosing pancreatic disease in dogs & cats
Recently developed, the serum feline pancreatic lipase immunoreactivity (fPLI) test may result in greater sensitivity than any other currently available feline diagnostic test. The current “gold standard” of diagnosing pancreatitis in cats by pancreatic biopsy and histology may be changed to the fPLI test, however, further studies regarding the true predictive value of the fPLI assay are in progress. (ACVIM Annual Forum Proceedings, Charlotte, NC, June, 2003)
For more information. . .
Strombeck, D. Strombeck's Small Animal Gastroenterology, 3rd Edition. 1996. page 385
Information on diagnosing feline pancreatitis. . .
Swift, N. C., et al. Evaluation of serum feline trypsin-like immunoreactivity for the diagnosis of pancreatitis in cats. JAVMA Vol. 217. No. !, July 1, 2000
Williams DA, Bratt RM: Sensitivity and specificity of radioimmunoassay of serum trypsin-like immunoreactivity for the diagnosis of exocrine pancreatic insufficiency. JAVMA 192: 195-201, 1988.
