Effect of pancreatectomy on plasma activities of amylase, isoamylase, lipase and trypsin-like immunoreactivity in dogs.

The contribution of the pancreas to the plasma activities of amylase, isoamylase, lipase and the concentration of trypsin-like immunoreactivity (TLI) in the dog was examined by measuring the activities of these enzymes before and after total pancreatectomy. Pancreatectomy was followed by a decrease in the concentration of TLI (from 6.2 +/- 0.3 micrograms litre-1 to 1.2 +/- 0.3 micrograms litre-1; P less than 0.001) and activity of isoamylase peak 4 (from 1257 +/- 105 iu litre-1 to 894 +/- 171 iu litre-1; P less than 0.05). Though significantly reduced, the activities of peak 4 isoamylase were still within the normal range for control dogs. Pancreatectomy did not significantly alter the activities of amylase, lipase or isoamylase peaks 1, 2 and 3. These findings provide strong evidence that the pancreas is not the sole source of circulating amylase, isoamylase and lipase activities. In contrast the marked reductions in TLI to values close to the limits of assay sensitivity suggest that TLI is derived from the pancreas alone. The results indicate that assay of circulating TLI provides a more sensitive and specific indicator of pancreatic exocrine mass than plasma amylase, lipase or isoamylase activities.     

Serum amylase and lipase activities after exploratory laparotomy in dogs

Serum amylase and lipase activities and creatinine concentration were determined before surgery, and at 1 and 2 days after exploratory laparotomy in 24 dogs. Examination of all viscera was done during each laparotomy, but a surgical procedure was not performed. The mean serum activities for lipase were: before surgery, 0.71 (0.0 to 2.0) Cherry Crandall units (CCU)/L; 1 day after surgery, 2.1 (0.0 to 4.5) CCU/L; and 2 days after surgery, 1.19 (0.0 to 3.9) CCU/L. The mean serum activities for amylase were: before surgery, 1,958 (1,027 to 3,426) IU/L; 1 day after surgery, 1,538 (937 to 2,659) IU/L; and 2 days after surgery, 1,663 (1,066 to 2,274) IU/L. Serum creatinine concentrations before surgery, 1 day after surgery, and 2 days after surgery were 0.88 (0.2 to 1.7) mg/dl, 0.78 (0.4 to 1.3) mg/dl, and 0.78 (0.3 to 1.3) mg/dl, respectively. Mean preoperative, day-1, and day-2 serum amylase activities and serum creatinine concentrations did not differ significantly from each other. Mean preoperative and day-2 serum lipase activities did not differ significantly; however, mean serum lipase activity was significantly greater when day 1 activities were compared with preoperative activities (P = 0.0002). Post-mortem examinations revealed no gross or histologic evidence of pancreatitis in any dog. The results of this study show that a 3 or more fold increase in serum lipase activity may occur after routine exploratory laparotomy in dogs without clinical signs or gross evidence of pancreatitis. Histologic evidence of pancreatitis was not found in the right pancreatic lobes in any dog.     

Effects of dexamethasone on pancreatic tissue and on serum amylase and lipase activities in dogs

The effects of dexamethasone on the pancreas and on pancreatic amylase and lipase activities were determined in clinically normal dogs and in dogs with neurologic disease. Dexamethasone increased serum lipase activity without any histologic damage to the pancreas in either group of dogs. It decreased serum amylase activity in the normal dogs and had a variable effect in dogs with neurologic disease, with or without confirmed pancreatitis. It was suggested that high serum lipase activity in dexamethasone-treated dogs may not be attributable to pancreatitis and that the reasons are still unknown. It was concluded that high serum lipase activity is an unreliable basis for diagnosis of pancreatitis in dogs treated with dexamethasone. The data allowed no conclusion about an additive effect of dexamethasone and neurologic disease causing pancreatitis.     

Serum lipase activities and pancreatic lipase immunoreactivity concentrations in dogs with exocrine pancreatic insufficiency

OBJECTIVE: To determine serum lipase activities and pancreatic lipase immunoreactivity (PLI) concentrations in dogs with exocrine pancreatic insufficiency (EPI). ANIMALS: 74 healthy dogs and 25 dogs with EPI. PROCEDURES: A diagnosis of EPI was made on the basis of clinical signs, low serum trypsin like immunoreactivity (TLI) concentration, and response to treatment with enzyme replacement. Median values for fasting serum lipase activity and serum PLI concentrations were compared between the 2 groups with a Mann-Whitney U test. RESULTS: Median fasting serum lipase activity was not significantly different between dogs with EPI (366.0 U/L) and healthy dogs (294.5 U/L), and only 1 dog with EPI had a serum lipase activity less than the lower limit of the reference range. Median serum PLI concentration was significantly lower in dogs with EPI (0.1 microg/L) than in healthy dogs (16.3 microg/L). All dogs with EPI had serum PLI concentrations less than the lower limit of the reference range. CONCLUSION AND CLINICAL RELEVANCE: Serum lipase activity is not limited to the exocrine pancreas in origin, whereas serum PLI is derived only from the exocrine pancreas. Unlike in serum TLI concentrations, there was a small degree of overlap in serum PLI concentrations between healthy dogs and dogs with EPI. Serum TLI concentration remains the test of choice for diagnosis of EPI.     

Serum values of amylase and pancreatic lipase in healthy mature dogs and dogs with experimental pancreatitis

Serum values of amylase and pancreatic lipase were determined by the iodometric and the turbidimetric methods, respectively, in 44 mature healthy dogs and in 8 dogs with experimentally induced pancreatitis (plus 1 sham-operated control). Serum value of amylase in mature healthy dogs varied from 250 to 1,500 Caraway units/dl and that of pancreatic lipase varied from 0 to 50 IU/L. Maximal serum values of amylase and pancreatic lipase in the dogs with experimentally induced pancreatitis varied from 4,540 to 14,000 Caraway units/dl and 325 to 810 IU/L, respectively. Following pancreatic damage, serum values of amylase and pancreatic lipase increased rapidly in the 8 dogs and ran parallel to each other in 6 of the 8 dogs studied. However, the serum value of amylase returned to within normal range earlier than the serum value of pancreatic lipase in 2 dogs; the reverse was true in 2 other dogs.     

Sensitivity and specificity of canine serum total amylase and isoamylase activity determinations.

Serum isoamylases were determined prospectively in dogs with pancreatic and extrapancreatic diseases. Mean serum isoamylase determinations were significantly different (p less than 0.05) between normal dogs and dogs with pancreatitis and exocrine pancreatic insufficiency. The sensitivity of serum isoamylase determination exceeded that of total amylase activity for the diagnosis of pancreatitis. Serum isoamylase determinations were less influenced by extrapancreatic diseases compared to total amylase activity when used in the diagnosis of pancreatic disease. Neither serum isoamylase determination nor total amylase activity had adequate sensitivity to support their use in the diagnosis of exocrine pancreatic insufficiency. There were significant (p less than 0.05) linear correlations between isoamylase determinations, total amylase activity, and trypsin-like immunoreactivity concentration.     

COMBINED USE OF ULTRASONOGRAPHY AND CONTRAST ENHANCED COMPUTED TOMOGRAPHY TO EVALUATE ACUTE NECROTIZING PANCREATITIS IN TWO DOGS

The imaging findings in two miniature schnauzers with acute necrotizing pancreatitis are described. Both dogs were treated previously for diabetes mellitus and hyperlipidemia. Vomiting, anorexia, and lethargy were observed in both dogs at presentation. Laboratory evaluations supportive of pancreatitis included left shift, abnormally high serum amylase and lipase activities, hypocalcemia, and abnormally high serum activities of liver enzymes. Sonographically, both dogs had diffusely enlarged hypoechoic pancreatic tissue with anechoic foci compatible with necrosis, abscessation, phlegmon, and pseudocysts formation. Contrast-enhanced computed tomography (CT) findings in both dogs were compatible with pancreatic necrosis. Dog 1 was managed medically for 11 days. Follow-up CT scan in this dog disclosed decreased pancreatic size and increased contrast enhancement compatible with partial resolution of pancreatitis.     

Serum pancreatic polypeptide and amylase concentrations in dogs with experimentally induced acute pancreatitis

Serum concentrations of immunoreactive pancreatic polypeptide (IPP) were measured serially for 7 days after experimental induction of acute hemorrhagic pancreatitis in dogs by infusion of oleic acid into the pancreatic duct. The mean serum IPP concentrations in dogs with pancreatitis were increased significantly (P = 0.013) for 96 hours after induction of pancreatitis. Providing food at 108 hours resulted in significant increases (P = 0.032) in mean serum IPP concentrations in sham-operated control dogs compared with dogs with induced pancreatitis. This was attributed to cephalic-phase release of IPP due to a conditioned response that resulted from feeding immediately after each blood sampling. Mean serum IPP concentrations returned to base line more quickly than did mean serum amylase concentrations in dogs with pancreatitis.     

A Comparison of Two Methods of Partial Pancreatectomy in the Dog

Partial pancreatectomy was performed in 9 dogs by dissection and ligation of the pancreatic ductule and blood vessels, and in 10 dogs by a suture fracture technique. The dogs were evaluated for detrimental effects by (1) monitoring clinical signs and serum amylase and lipase activities and (2) examining the excision sites grossly and histologically at necropsy. There were no clinically apparent detrimental effects with either technique. The suture fracture technique evoked more histologic inflammation than the dissection and ligation technique.     

Diagnosis of pancreatitis.

In summary, pancreatitis is common in dogs and cats, but it seems that most cases remain undiagnosed. Serum amylase and lipase activities are useful as a quick screening test for pancreatitis in the dog only. Serum amylase or lipase activity must be at least three to five times the upper limit of the reference range to suggest a diagnosis of pancreatitis. Furthermore, the diagnosis must be confirmed by other diagnostic modalities, and normal test results do not eliminate the possibility of pancreatitis. Abdominal ultrasound is highly specific for pancreatitis in dogs and cats but is not particularly sensitive, especially in cats. Serum cPLI concentration is highly specific for exocrine pancreatic function and is also highly sensitive for pancreatitis. Similarly, initial data would suggest that serum fPLI is the most sensitive and specific diagnostic test for feline pancreatitis. Until further data are available, however, serum fPLI should be used in conjunction with other diagnostic tests to arrive at a diagnosis of feline pancreatitis. Histopathologic evidence of pancreatitis is conclusive for a diagnosis of pancreatitis. In most cases, however, lesions are localized, and the lack of histopathologic evidence of pancreatitis does not eliminate a diagnosis of pancreatitis.     

Effects of an anticholinergic and a corticosteroid on acute pancreatitis in experimental dogs

In a model developed to study acute pancreatitis in the dog, the disease process was comparable with the spontaneously occurring disease. Infusion of oleic acid into the accessory pancreatic duct induced, grossly and microscopically, acute hemorrhagic pancreatitis with pancreatic atrophy, fibrosis, fat necrosis, and edema. Clinical changes included persistent fever and tachycardia in all dogs and abdominal pain, vomiting, and diarrhea in most. Serum amylase and lipase activities increased markedly as did activities of alkaline phosphatase, aspartate aminotransferase, and alanine aminotransferase. Hematologic alterations included hemoconcentration (despite intensive fluid therapy) and leukocytosis due primarily to neutrophilia and monocytosis. Neither corticosteroid nor anticholinergic therapy begun 24 to 32 hours after oleic acid infusion altered the course of the disease. Dogs survived 8 days and appeared clinically normal when the study was terminated.     

Elevated canine pancreatic lipase immunoreactivity concentration in dogs with inflammatory bowel disease is associated with a negative outcome

O bjectives : To investigate whether elevated canine pancreatic lipase immunoreactivity (CPLI) concentrations in dogs with inflammatory bowel disease (IBD) is associated with a worse clinical outcome.
M ethods : Serum CPLI assays were performed on serum stored from cases diagnosed with IBD. Thirty-two dogs with CPLI results within the reference range were designated as the control group and 15 dogs had CPLI above the reference range. Clinical signs, age, serum lipase and amylase activities, serum albumin and cobalamin concentrations, abdominal ultrasound examination, histopathology on small intestinal biopsies, management of IBD and outcome were compared between the two groups.
R esults : No significant differences were found in clinical activity score (P=0·54), number of antibiotic-responsive disease cases (P=0·480), number of steroid-responsive disease cases (P=0·491), serum amylase activity (P=0·058), serum cobalamin concentration (P=0·61), serum albumin concentration (P=0·052), abdominal ultrasound score (P=0·23) and histopathology scores for IBD (P=0·74) between the two groups. Dogs with increased CPLI concentration were significantly older and had a higher serum lipase activity than dogs with a CPLI concentration within the normal reference range (P=0·001, P=0·001, respectively). Moreover, dogs with increased CPLI concentration responded poorly to steroid treatment (P=0·01) and were significantly more likely to be euthanased at follow-up (P=0·02).
C linical S ignificance : CPLI should be measured in cases of canine IBD as elevated CPLI was associated with a worse outcome.     

Serum amylase and lipase activities in the diagnosis of pancreatitis in dogs

To determine the usefulness of information provided by measurement of serum amylase activity in the evaluation of dogs for pancreatitis, the relationship of amylase activity to lipase activity in 713 paired serum samples was investigated by statistical analysis. Little change in mean amylase concentration was found until lipase values exceeded 800 U/L. The ranges of amylase activity (mean +/- 2 SD) were essentially the same for dogs with no pancreatitis (0 to 100 U of lipase activity/L) as for dogs with a high probability for the disease (700 to 799 U of lipase activity/L), 0 to 4,029 U/L and 857 to 4,869 U/L, respectively. Pathologic findings from biopsy and necropsy reports from 92 dogs for which serum lipase determinations were done indicated that serum lipase increased not only with pancreatitis, but also with other medical problems, such as renal and hepatic disease. It was concluded that determination of serum amylase activity without knowledge of serum lipase activity was of little value to diagnose pancreatitis. High amylase activity was not specific for pancreatitis and low amylase activity could not rule out the disease. The results of this study also showed that low serum lipase values almost always eliminated the possibility of pancreatitis and that high values were often, but not always, diagnostic for pancreatitis.     

Assessing the severity of canine pancreatitis

The objective of this study was to determine whether laboratory testing currently available is able to provide prognostic information in canine pancreatitis. A prospective study of dogs with naturally occurring pancreatitis was undertaken. Twenty-two cases with histologically confirmed pancreatic inflammation were included in the study. Each dog had routine haematology parameters, serum biochemistry (including lipase and amylase), serum trypsin-like immunoreactivity and trypsinogen activation peptides (TAP) in urine and plasma measured. Twelve of the dogs were classified as having severe disease. These dogs had statistically significant increases in urinary TAP-creatinine ratio (UTCR) measurement, serum lipase, serum phosphate and serum creatinine concentrations. Additionally dogs with severe pancreatitis had significantly decreased urine specific gravity levels. The most sensitive and specific test to assess the severity of pancreatitis was the measurement of UTCR.     

Comparison of amylase and lipase activities in serum and plasma of dogs

BACKGROUND: Amylase and lipase activities are most often determined in serum, although heparinized plasma is more convenient to obtain and is used for many routine biochemical analyses. OBJECTIVE: The purpose of this study was to compare amylase and lipase activities in serum and plasma of dogs and to determine whether either specimen type is acceptable for analysis. METHODS: Serum and heparinized plasma were obtained from 101 randomly selected dogs and analyzed in parallel for alpha-amylase and lipase. Results were compared using Passing-Bablock regression, Bland-Altman difference plots, and correlation analysis. RESULTS: There was a high correlation between the results obtained from serum and those from plasma. Regressions (with 95% confidence intervals in parentheses) were as follows: lipase(plasma) = 0.984 (0.976/0.995) Chi lipase(serum) - 0.9 (2.9/0.7) (r =.999); a-amylase(plasma) = 1.003 (0.977/1.032) Chi alpha-amylase(serum) - 1.9 ( 20.7/23.3) (r =.991). Mean differences (serum - plasma) were 8 U/L and 4 U/L for lipase and alpha-amylase, respectively. Classification of results as normal or abnormal did not differ according to specimen type. CONCLUSION: In dogs, lipase and alpha-amylase activities can be determined with the same level of accuracy in serum and in heparinized plasma.     

Evaluation of serum values of pancreatic enzymes after endoscopic retrograde pancreatography in dogs

OBJECTIVE: To assess the safety of endoscopic retrograde pancreatography (ERP) in dogs by performing repeated clinical examinations and laboratory analyses of serum amylase, lipase, canine trypsin-like immunoreactivity (cTLI), and canine pancreatic elastase 1 (cE1) after the procedure. ANIMALS: 7 healthy Beagles. PROCEDURES: Clinical examinations were performed and blood samples obtained for serum enzyme determinations before and at intervals (10 minutes; 2, 4, and 6 hours; and 1, 2, and 3 days) after ERP. RESULTS: Repeated clinical examinations revealed no signs of ERP-induced complications in the 7 dogs. Results of repeated laboratory tests indicated a transient increase in serum values of amylase, lipase, and cTLI but not cE1. Mean +/- SD lipase activity increased from 120.7 +/- 116.4 U/L to 423.4 +/- 243.1 U/L at 4 hours after ERP. Median serum cTLI concentration increased from 16.2 microg/L (range, 77 to 26.5 microg/L) to 34.9 microg/L (range, 16.6 to 68.3 microg/L) 10 minutes after ERP. Enzyme values returned to baseline levels at the latest on day 2 in 6 of 7 dogs. Highest values for serum amylase, lipase, and cTLI and their delayed return to baseline values were detected in 1 dog with contrast filling of the pancreatic parenchyma. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that ERP appears to be a safe imaging technique of pancreatic ducts in healthy dogs, although it induced a transient increase in serum values of pancreatic enzymes. In dogs, repeated clinical examinations and serum enzyme determinations can be used to monitor ERP-induced complications such as acute pancreatitis.     

Sensitivity and specificity of radioimmunoassay of serum trypsin-like immunoreactivity for the diagnosis of canine exocrine pancreatic insufficiency

Concentrations of serum trypsin-like immunoreactivity (TLI) measured by radioimmunoassay were low (less than 1.9 micrograms/L) in 25 dogs with exocrine pancreatic insufficiency (EPI), compared with 100 clinically normal (control) dogs (5.2 to 34.0 micrograms/L; P less than 0.001; sensitivity, 100%). Serum TLI concentrations (5.5 to 35.0 micrograms/L) in a group of 50 dogs with small intestinal disease (SID) were not significantly different from those of control dogs, values being greater than the lower limit of the control range in all cases (specificity, 100%). Results of bentiromide (N-benzoyl-L-tyrosyl-p-aminobenzoic acid [BT-PABA]) tests and fecal proteolytic activity (determined by use of an azocasein substrate) were abnormal in 21 of 22 dogs with EPI (sensitivity, 95%). Bentiromide test results were subnormal in 13 of 35 dogs with SID (specificity, 63%), whereas fecal proteolytic activity was subnormal in 7 of 34 dogs with SID (specificity, 79%). It was concluded that assay of serum TLI is a highly sensitive and specific test for the identification of dogs with EPI.     

Model of chronic pancreatitis in the dog

A model of chronic pancreatitis was developed and characterized in the dog. Pancreatitis was produced by infusion of oleic acid through a cannula in the accessory pancreatic duct. Biochemical changes included early and marked increases in serum amylase and lipase activities which returned to base line within 3 weeks, at which time the dogs were clinically normal. In dogs euthanatized within 2 weeks, pathologic changes included massive necrosis and hemorrhage, cystic spaces filled with fluid, and abscesses. Histologic features revealed acute exudative pancreatitis with pancreatic atrophy and fibrosis. In dogs killed between weeks 3 to 12, changes included: marked atrophy with remaining acini surrounded by remnants consisting of collapsed stroma, blood vessels, and pancreatic ducts; marked coarse fibrosis with scattered inflammatory cells and occasional acinar tissue; and large irregular pseudocysts.     

Indocyanine green clearance and ammonia tolerance in partially hepatectomized and hepatic devascularized, anesthetized dogs

Indocyanine green clearance and ammonia tolerance were measured in anesthetized dogs with 60% hepatectomy, 40% hepatectomy, portacaval shunt, and hepatic artery ligation. With a dose of 0.5 mg of indocyanine green/kg of body weight, plasma clearance of the dye was significantly (P less than 0.001) delayed only in dogs with 60% hepatectomy. Ammonia tolerance was abnormal in dogs in this group, because after they were given a gastric challenge load of an ammonium salt, they had a 5-fold increase in plasma ammonia concentration, compared with a 2.5-fold increase in the control group. Before challenge loading, base-line plasma ammonia concentration was significantly (P less than 0.05) increased within 5 minutes after surgical preparation of the portacaval shunt. After challenge loading the stomach with an ammonium salt, dogs with portacaval shunt had increased plasma ammonia concentration, but the amount was not significantly different from postchallenge-loading values in control dogs. Dogs with 40% hepatectomy and with hepatic artery ligation could not be differentiated from control dogs by indocyanine green clearance or by ammonia tolerance testing. Abnormal tolerance to a challenge gastric load of an ammonium salt or delayed clearance of indocyanine green may indicate marked loss of functional hepatic mass, but normal tolerance or normal dye clearance may not exclude liver disease or dysfunction. Seemingly, base-line plasma ammonia concentration was a sensitive indicator of abnormal portal circulation.(ABSTRACT TRUNCATED AT 250 WORDS)     

Hyperglycaemia but not hyperlipidaemia decreases serum amylase and increases neutrophils in the exocrine pancreas of cats

The goal of the study was to determine whether hyperglycaemia or hyperlipidaemia causes pancreatitis in cats and to assess the effect of excess serum glucose and lipids on amylase and lipase activity. Ten-day hyperglycaemic and hyperlipidaemic clamps were carried out in five and six healthy cats, respectively. Ten healthy cats received saline and served as controls. The activity of amylase was below the normal range in 4 of 5 hyperglycaemic cats by day 10. The activity of lipase did not vary in any of the cats. Samples of exocrine pancreas were normal on histological examination, but the number of tissue neutrophils was increased in hyperglycaemic cats (P < 0.05). In a retrospective study 14 of 40 (35%) cats with naturally occurring diabetes mellitus had amylase activities below the reference range at the time of admission. Amylase activities normalised within 1 week of insulin therapy and subsequent glycaemic control. Lipase activity was increased in 26 of 40 (65%) diabetic cats and remained elevated despite glycaemic control. In conclusion, hyperglycaemia, but not hyperlipidaemia, increases pancreatic neutrophils in cats. However, because the histological morphology of the exocrine pancreas was normal, hyperglycaemia may play only a minor role in the pathogenesis of pancreatitis. Low amylase activities in diabetic cats may reflect an imbalance in glucose metabolism rather than pancreatitis.