Feline Pancreatic Lipase

Feline Pancreatic Lipase

 

LIN, WEN-YANG (WESLEY), Ph.D

 

Feline Pancreatic Lipase is a powerful diagnosing biomarker for feline pancreatitis, whereas serum amylase and serum lipase are usually used in diagnosing pancreatitis for canine, are not effectively in detecting pancreatitis for cats.

 

Anatomical physiology function of pancreas in cats

The feline pancreas is a digestive glandular organ, which presents a long v-shaped strip of configuration locating at abdomen between stomach and duodenum. The tail part of feline pancreas rests toward the dorsal extremity of the spleen and connect to mesocolon with omentum (Figure 1).

 

Figure 1. Anatomic view of the pancreas and its surrounding tissues

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The normal pancreas colored on pale pink and perform both functions of endocrine and exocrine. The endocrine portion contains small clusters of pancreatic α- and β-cells within Langerhans (approximately 2% of the gland’s weight) that majorly generates two hormones proteins: glucagon and insulin. Glucagon works to elevate the level of blood sugar, whereas insulin would diminish excess circulating blood sugar. Both of glucagon and insulin would take part in regulating homeostasis of glycemic level.

 

Acinar and ductal cells are major members in the exocrine portion of pancreas. Acinar cells aggregate around the terminal pancreatic ductules to secrete digestive enzymes include trypsinogen, chymotrypsinogen, proelastase, procarboxypeptidase, ribonucleases, deoxyribonucleases, phospholipase A2, carboxylesterase amylase and lipase. Amylase and lipase are contributing to hydrolyze carbohydrates and fat. Others may play roles as proteases to cleave polypeptide chains. Feline’s ductal cell generates antibacterial proteins to protect small intestinal from bacterial infection. Moreover, ductal cell can also produce bicarbonate and water for neutralizing pH in the duodenum. Intrinsic factor such as vitamin B12 would be made from ductal cell too. The pancreas is the only generating organ of intrinsic factor for feline, whereas dogs could produce intrinsic factor from pancreas and stomach. All pancreatic enzymes would secret into small intestine for digesting fats, proteins and carbohydrates. Furthermore, the abnormal seep of exocrine enzymes to pancreas and its surrounding organs could cause pancreatic inflammation known as pancreatitis. The highest occurrence of feline pancreatic diseases is exocrine pancreatic insufficiency (EPI) and pancreatitis.

 

Pancreatitis in the cat

Feline pancreatitis is classified as acute (temporary morphological changes) and chronic (permanent morphological change) type according to the condition of histopathologic changes after treatment. Acute necrotizing pancreatitis (ANP) and acute suppurative pancreatitis are two of the most common types of acute feline pancreatitis, whereas chronic non-suppurative pancreatitis (CP) and pancreatic atrophy are chronic conditions.

 

Common acute pancreatitis in feline would show anemia, leukocytosis, hypokalemia, hypocalcemia, hyperglycemia, elevation of ALT, ALP, total bilirubin, cholesterol and decreasing level of albumin. Acute necrotizing pancreatitis (ANP) usually present pancreatic acinar cell necrosis, peripancreatic fat necrosis followed inflammation, hemorrhage, mineralization and fibrosis. Despite of its idiopathic character, several diseases have considered to be related with development of ANP including concurrent biliary tract disease, ischemia, pancreatic ductal obstruction, toxoplasmosis, feline Herpes virus infections, feline infectious peritonitis, pancreatic fluke infestations (Eurytrema procyonis, Amphimerus pseudofelinus), trauma, organophosphate poisoning and hepatic lipidosis. General anesthesia induced hypotension or surgical venous outflow occlusion would decrease pancreatic blood flow and cause ANP. Acute suppurative pancreatitis is less common than ANP in feline and neutrophilic inflammation would happen with it.

 

Besides, the continuous and progressive inflammatory process of the pancreas would lead to chronic non-suppurative pancreatitis (CP) in which lymphocytic inflammation, fibrosis, and acinar atrophy are the major features. The end stage of CP in most feline cases would usually result in pancreatic atrophy, which may or may not influence the endocrine portion of the gland. Felines who suffer pancreatic atrophy would occur cobalamin and fat-soluble vitamin malabsorption, severe maldigestion, acid injury in duodenal mucosa, and bacterial proliferation in the gut due to exocrine pancreatic insufficiency.

 

Since various types of pancreatitis such as acute and chronic pancreatitis, pancreatic abscess, pancreatic cyst/pseudocyst, exocrine pancreatic insufficiency, and neoplasia share overlapping symptoms, thus histopathology cab be used to discern different conditions.

 

Symptoms of feline pancreatitis

Symptoms of feline pancreatitis would occur lethargy, anorexia, dehydration, hypothermia, vomiting, weight loss, Jaundice, cholangiohepatitis, hepatic lipidosis, biliary obstructions, cranial abdominal masses and cranial abdominal discomfort. Besides, hepatic and intestinal disease would concurrent.

 

I. Acute feline pancreatitis:

Vomiting, poor appetite, poor activity, diarrhea, abdominal pain, drooling, fever, collapse.

 

II. Chronic feline pancreatitis:

Frequent vomiting, poor appetite, listless, frequent diarrhea, abdominal pain, drooling, fever, collapse, hypothermia, breathing too fast or too slow, fast heartbeat.

 

Possible Causes of feline pancreatitis

Scientists presumed that premature trypsin activate of digestive zymogens in pancreatic acinar cells would cause pancreatic autodigestion, acinar cell necrosis, hemorrhage, and fat necrosis, saponification, mast cell degranulation, leukocyte chemotaxis, platelet aggregation, vasodilation, surfactant degradation within the lungs and initiation of disseminated intravascular coagulation (DIC) for worse cases.

 

Diagnosis and general considerations

Since symptoms of feline pancreatitis were similar to common flu, vets probably can’t judge it correctly at the early stage without proper diagnostic tools. It’s not an easy task to diagnose pancreatic disease within cats. Single diagnostic method is not recommended. The diagnosis of feline pancreatitis relied on combinational diagnostic tools include historical data, physical examination results, laboratory, and Bio-imaging. Especially, histopathology plays the role as the definitive conclusion for feline pancreatitis.

 

Middle-aged felines are susceptible to pancreatitis; whereas, older felines (mean 12.8 years, range 4–20 years) are susceptible to neoplasia, cyst/pseudocysts.

 

Diagnostic imaging

Radiography, computed tomography (CT) and ultrasonography were effective imaging tools applied in diagnosing feline pancreatitis. Among all imaging tools, ultrasonography is the most reliable imaging modality for the diagnosis of feline pancreatic diseases, which can help identify soft tissue masses, cysts/pseudocysts, abscesses, or neoplasia and lesions of feline pancreatitis.

 

Clinicopathologic tests

The general clinicopathologic test for feline pancreatitis include complete blood cell count, serum bilirubin, cholesterol, glucose, total protein, albumin, and serum activity of liver enzymes (serum alanine aminotransferase and alkaline phosphatase), calcium, urea, creatinine, and potassium. However, serum lipase and amylase activities can’t be diagnostic indicator for feline pancreatic disease. Nevertheless, feline trypsin-like immunoreactivity (fTLI) and feline pancreatic lipase immunoreactivity (fPLI) have been validated as effective and reliable species-specific immunoassays for measuring feline pancreatic disease. In laboratory test, feline trypsin-like immunoreactivity (fTLI) is less sensitive in detecting feline pancreatitis than feline pancreatic lipase immunoreactivity (fPLI) (see Table 1).

 

Measuring feline pancreatic lipase (fPL)

Feline pancreatic lipase immunoreactivity (fPLI) has been recommended as a highly sensitive and specific blood test for diagnosing pancreatitis in cats. The fPLI test requires only a simple blood sample and is performed within few minutes. It’s able to diagnose moderate to severe pancreatitis (Table 1). Besides, fPLI can be applied in monitoring feline response to treatment due to its rapid blood clearance. Some commercial fPL rapid tests has released for detecting feline pancreatitis at the early stage.

 

Table 1. Pancreas-specific serum tests (https://veteriankey.com/pancreas-4/)

 

Treatment for feline pancreatitis

 

I. Intravenous fluid therapy and electrolyte supplementation

Pancreatitic felines usually occur hypokalemic and hypocalcemic, thus it’s an important issue of maintaining fluid, acid–base and electrolyte deficits. Crystalloids (lactated Ringers or 0.9% NaCl) should be given at first. Calcium gluconate is recommended under a dose of 50–150 mg/kg IV over 12–24 hours. Once cats present a low packed cell volume below 15–20%, plasma transfusion of after blood typing would be necessary. Transfusion of whole blood probably can elevate concentrations of albumin for maintaining plasma oncotic press and reducing pancreatic edema. The level of α-macroglobulins may also uplifted by plasma transfusion that can bind on certain proteases to combat DIC.

 

II. Nutritional Support

Ideally, low fat and high carbohydrate diet with small frequent portions is suggested. Fasting is only recommended for severe vomiting at risk for aspiration pneumonia in cats. Some cases of feline chronic pancreatitis will occur exocrine pancreatic insufficiency and then oral pancreatic enzyme extract will be required. Vitamin B12 supplement may help in cases with concurrent GI disease.

 

III. Drugs

Feline pancreatitis usually present abdominal pain in cats, thus opioid analgesia is considered to be ideal analgesic therapy. Buprenorphine, methadone, morphine, or fentanyl can be potent and useful in relieving pain. Non-steroidal anti-inflammatory drugs are avoided due to its renal toxicity in dehydrated or hypovolaemic felines. In addition, anti-emetics such as maropitantm and metoclopramide would benefit cases with vomiting and inappetance. Antibiotic treatment may be required in some cases of chronic pancreatitis who have gram-negative bacteria associated around the pancreatic ducts. If cases show evidence of gastric ulceration, antacids such as omeprazole and ranitidine are recommended. Furthermore, corticosteroids are suggested to apply in concurrent Inflammatory bowel disease (IBD) alongside considering monitoring fPLI concentrations. Finally, concurrent diseases such as inflammatory liver, pancreatic, intestinal disease, diabetes mellitus and hepatic lipidosis can also be present.

 

IV. Surgery

When occurring situations like persistent pancreatic mass, sepsis or extraluminal bile duct obstruction aren’t responsive to medical treatment, administration of surgery should be considered. Common invasive surgery to deal pancreatic related diseases include splenectomy, cholecystoduodenostomy, cholecystojejunostomy, cholecystostomy and choledochal stenting.

 

References

1. Owens JM, Dranzner FH, Gilbertson SR. Pancreatic disease in the cat. J Am Anim Hosp Assoc 1975;11:83–89.
2. Kitchell BE, Strombeck DR, Cullen J, Harrold D. Clinical and pathologic changes in experimentally induced acute pancreatitis in cats. Am J Vet Res 1986;47:1170–1173.
3. Saunders HM, VanWinkle TJ, Drobatz K, et al. Ultrasonographic findings in cats with clinical, gross pathologic, and histologic evidence of acute pancreatic necrosis: 20 cases (1994–2001). J Am Vet Med Assoc 2002;221:1724–1730.
4. Swift NC, Marks SL, MacLachlan NJ, Norris CR. Evaluation of serum feline trypsin-like immunoreactivity for the diagnosis of pancreatitis in cats. J Am Vet Med Assoc 2000;217:37–42.
5. Shams J, Stein A, Cooperman A. Computed tomography for pancreatic diseases. Surg Clin North Am 2001;81:283–306.
6. Luetmer PH, Stephens DH, Ward EM. Chronic pancreatitis: reassessment with current CT. Radiology 1989;171:353–357.
7. Bruner JM, Steiner JM, Williams DA, et al. High feline trypsinlike immunoreactivity in a cat with pancreatitis and hepatic lipidosis. J Am Vet Med Assoc 1997;210:1757–1760.
8. Steiner JM, Williams DA. Feline trypsin-like immunoreactivity in feline exocrine pancreatic disease. Comp Cont Educ Pract Vet 1996; 18:543–547.
9. Simpson KW, Shiroma JT, Biller DS, et al. Ante mortem diagnosis of pancreatitis in four cats. J Small Anim Pract 1994;35:93–99.
10. Steiner JM, Medinger TL, Williams DA. Development and validation of a radioimmunoassay for feline trypsin-like immunoreactivity. Am J Vet Res 1996;57:1417–1420.
11. Gerhardt A, Steiner JM, Williams DA, et al. Comparison of the sensitivity of different diagnostic tests for pancreatitis in cats. J Vet Intern Med 2001;15:329–33.
12. Steiner JM, Williams DA. Disagrees with criteria for diagnosing pancreatitis in cats. J Am Vet Med Assoc 2000;217:816–818.
13. Steiner JM, Wilson BG, Williams DA. Purification and partial characterization of feline classical pancreatic lipase. Comp Biochem Physiol B Biochem Mol Biol 2003;134:151–159.
14. Hittmair KM, Vielgrader HD, Loupal G. Ultrasonographic evaluation of gallbladder wall thickness in cats. Vet Radiol Ultrasound 2001;42:149–155.
15. Akol KG, Washabau RJ, Saunders HM, Hendrick MJ. Acute pancreatitis in cats with hepatic lipidosis. J Vet Intern Med 1993;7: 205–209.
16. Hines BL, Salisbury SK, Jakovljevic S, DeNicola DB. Pancreatic pseudocyst associated with chronic-active necrotizing pancreatitis in a cat. J Am Anim Hosp Assoc 1996;32:147–152.
17. Lamb CR. Recent developments in diagnostic imaging of the gastrointestinal tract of the dog and cat. Vet Clin North Am Small Anim Pract 1999;29:307–342.
18. Mayhew PD, Holt DE, McLear RC, Washabau RJ. Pathogenesis and outcome of extrahepatic biliary obstruction in cats. J Small Anim Pract 2002;43:247–253.
19. VanEnkevort BA, O’Brien RT, Young KM. Pancreatic pseudocysts in 4 dogs and 2 cats: ultrasonographic and clinicopathologic findings. J Vet Intern Med 1999;13:309–313.
20. Wall M, Biller DS, Schoning P, et al. Pancreatitis in a cat demonstrating pancreatic duct dilation ultrasonographically. J Am Anim Hosp Assoc 2001;37:49–53.
21. Etue SM, Penninck DG, Labato MA, et al. Ultrasonography of the normal feline pancreas and associated anatomic landmarks: a prospective study of 20 cats. Vet Radiol Ultrasound 2001;42:330–336.
22. Mansfield CS, Jones BR. Review of feline pancreatitis part two: clinical signs, diagnosis and treatment. J Fel Med Surg 2001;3:125–132.
23. Hill RC, Van Winkle TJ. Acute necrotizing pancreatitis and acute suppurative pancreatitis in the cat. A retrospective study of 40 cases (1976–1989). J Vet Intern Med 1993;7:25–33.
24. Balthazar EJ. Acute pancreatitis: assessment of severity with clinical and CT evaluation. Radiol 2002;223:603–613.
25. Sarner M. Pancreatic inflammatory disease. Gut 1995;37:455–456.
26. Sarles H, Adler G, Dani R, et al. The pancreatitis classification of Marseilles-Rome 1988. Scand J Gastroenterol 1989;24:641–642.
27. Chari ST, Singer MV. The problem of classification and staging of chronic pancreatitis. Proposals based on current knowledge of its natural history. Scand J Gastroenterol 1994;29:949–960.
28. Weiss DJ, Gagne JM, Armstrong PJ. Relationship between inflammatory hepatic disease and inflammatory bowel disease, pancreatitis, and nephritis. J Am Vet Med Assoc 1996;209:1114–1116.
29. Hirsch VM, Doige CE. Suppurative cholangitis in cats. J Am Vet Med Assoc 1983;182:1223–1226.
30. AKOL, K. G., WASHABAU, R. J., SAUNDERS, H. M. & HENDRICK, M. J. (1993) Acute pancreatitis in cats with hepatic lipidosis. Journal of Veterinary Internal Medicine

7, 205-209

31. BAEZ, J. L., HENDRICK, M. J., WALKER, L. M. & WASHABAU, R. J. (1999) Radiographic, ultrasonographic, and endoscopic findings in cats with inflammatory bowel disease of the stomach and small intestine: 33 cases (1990-1997). Journal of the American Veterinary Medical Association 215, 349-354
32. DAY, D. G. (1995) Feline cholangiohepatitis complex. Veterinary Clinics of North America: Small Animal Practice 25, 375-385 DAY, M. J., BILZER, T., MANSELL, J., WILCOCK, B., HALL, E. J., JERGENS, A., MINAMI, T., WILLARD, M. & WASHABAU, R. (2008) Histopathological standards for the diagnosis of gastrointestinal inflammation in endoscopic biopsy samples from the dog and cat: a report from the World Small Animal Veterinary Association Gastrointestinal Standardization Group. Journal of Comparative Pathology 138, S1-S43
33. DE COCK, H. E., FORMAN, M. A., FARVER, T. B. & MARKS, S. L. (2007) Prevalence and histopathologic characteristics of pancreatitis in cats. Veterinary Pathology 44, 39-49
34. DENNIS, J. S., KRUGER, J. M. & MULLANEY, T. P. (1993) Lymphocytic/plasmacytic colitis in cats: 14 cases (1985-1990). Journal of the American Veterinary Medical Association 202, 313-318
35. EVANS, S. E., BRONCZYNSKI, J. J., BROUSSARD, J. D., HAN, E. & BAER, K. E. (2006) Comparison of endoscopic and full-thickness biospy specimens for diagnosis of inflammatory bowel disease and alimentary tract lymphoma in cats. Journal of the American Veterinary Medical Association 229, 1447-50
36. FERRERI, J. A., HARDAM, E., KIMMEL, S. E., SAUNDERS, H. M., VAN WINKLE, T. J., DROBATZ, K. J. & WASHABAU, R. J. (2003) Clinical differentiation of acute necrotizing from chronic nonsuppurative pancreatitis in cats: 63 cases (1996-2001). Journal of the American Veterinary Medical Association 223, 469-474
37. FORMAN, M. A., MARKS, S. L., DE COCK, H. E., HERGESELL, E. J., WISNER, E. R., BAKER, T. W., KASS, P. H., STEINER, J. M. & WILLIAMS, D. A. (2004) Evaluation of serum feline pancreatic lipase immunoreactivity and helical computed tomography versus conventional testing for the diagnosis of feline pancreatitis. Journal of Veterinary Internal Medicine 18, 807-815
38. GERHARDT, A., STEINER, J. M., WILLIAMS, D. A., KRAMER, S., FUCHS, C., JANTHUR, M., HEWICKER-TRAUTWEIN, M. & NOLTE, I. (2001) Comparison of the sensitivity of different diagnostic tests for pancreatitis in cats. Journal of Veterinary Internal Medicine 15, 329-333
39. HANICHEN, T. & MINKUS, G. (1990) Retrospecktive studie zur pathologie der erkrankungen des exokrinen pancreas bei hund and katze. Tierorztl Umscb 45, 363-368
40. HILL, R. C. & VAN WINKLE, T. J. (1993) Acute necrotizing pancreatitis and acute suppurative pancreatitis in the cat. A retrospective study of 40 cases (1976- 1989). Journal of Veterinary Internal Medicine 7, 25-33
41. JANECZKO, S., ATWATER, D., BOGEL, E., GREITER-WILKE, A., GEROLD, A., BAUMGART, M., BENDER, H., MCDONOUGH, P. L., MCDONOUGH, S. P., GOLDSTEIN, R. E. & SIMPSON, K.
42. (2008) The relationship of mucosal bacteria to duodenal histopathology, cytokine mRNA, and clinical disease activity in cats with inflammatory bowel disease. Veterinary Microbiology 128, 178-193
43. JERGENS, A. E., CRANDELL, J. M., MORRISON J. A. & ALLENSPACH K. (2007) Serum acute phase proteins in feline inflammatory bowel disease, Abstract, ACVIM Forum Seattle, Washington, 2007
44. JERGENS, A. E., MOORE, F. M., HAYNES, J. S. & MILES, K. G. (1992) Idiopathic inflammatory bowel disease in dogs and cats: 84 cases (1987-1990). Journal of the American Veterinary Medical Association 201, 1603-1608
45. KATHRANI, A., STEINER, J. M., SUCHODOLSKI, J., EASTWOOD, J., SYME, H., GARDEN, O. A. & ALLENSPACH, K. (2009) Elevated canine pancreatic lipase immunoreactivity concentration in dogs with inflammatory bowel disease is associated with a negative outcome. Journal of Small Animal Practice 50, 126-132
46. PARENT, C., WASHABAU, R. J., WILLIAMS, D. A., STEINER, J. M., VAN WINKLE, T., SAUNDERS, H. M., NOAKER, L. J. & SHOFER, F. S. (1995) Serum trypsin-like immunoreactivity, amylase and lipase in the diagnosis of feline acute pancreatitis. Journal of Veterinary Internal Medicine 9, 194
47. RUAUX, C. G., STEINER, J. M. & WILLIAMS, D. A. (2005) Early biochemical and clinical responses to cobalamin supplementation in cats with signs of gastrointestinal disease and severe hypocobalaminemia. Journal of Veterinary Internal Medicine 19, 155-160
48. SAUNDERS, H. M., VANWINKLE, T. J., DROBATZ, K., KIMMEL, S. E. & WASHABAU, R. J. (2002) Ultrasonographic findings in cats with clinical, gross pathologic, and histologic evidence of acute pancreatic necrosis: 20 cases (1994-2001). Journal of the American Veterinary Medical Association 221, 1724-1730
49. SIMPSON, K. W., FYFE, J., CORNETTA, A., SACHS, A., STRAUSSAYALI, D., LAMB, S. V. & REIMERS, T. J. (2001) Subnormal concentrations of serum cobalamin (vitamin B12) in cats with gastrointestinal disease. Journal of Veterinary Internal Medicine 15, 26-32
50. STEINER, J. M., WILSON, B. G. & WILLIAMS, D. A. (2004) Development and analytical validation of a radioimmunoassay for the measurement of feline pancreatic lipase immunoreactivity in serum. Canadian Journal of Veterinary Research 68, 309-314
51. WEISS, D. J., GAGNE, J. M. & ARMSTRONG, P. J. (1996) Relationship between inflammatory hepatic disease and inflammatory bowel disease, pancreatitis, and nephritis in cats. Journal of the American Veterinary Medical Association 209, 1114-1116
52. 50. ZORAN, D. L. (2006) Pancreatitis in cats: diagnosis and management of a challenging disease. Journal of the American Animal Hospital Association 42, 1-9