Pancreatic stone protein: quantification in pancreatic juice by enzyme-linked immunosorbent assay and comparison with other methods

To quantitate pancreatic stone protein (PSP), a competitive radioimmunoassay using monoclonal antibodies to PSP extracted from pancreatic stones and a sandwich enzyme-linked immunosorbent assay (ELISA) using monospecific polyclonal antibodies to the secretory forms of PSP (PSP S) were established. When PSP concentrations were measured in pancreatic juice by radioimmunoassay, no difference could be found between patients suffering from chronic calcifying pancreatitis and other diagnostic groups. Yet, with the ELISA technique involving polyclonal antibodies, decreased concentrations were found in chronic calcifying pancreatitis patients when compared to controls (p less than 0.001), chronic alcoholics without pancreatic symptoms, or obstructive pancreatitis patients. These discrepancies are discussed. The monoclonal antibodies recognizing the C-terminal part of PSS S (PSP S1), results from the radioimmunoassay indicate that the concentration of that polypeptide is identical in the juice of controls and patients. Results from the ELISA obtained with polyclonal antibodies raised against PSP S2-5 molecules, i.e., recognizing the PSP S1 part and the N-terminal portion of the molecule, indicate that the differences observed reflect differences in the juice concentration of that N-terminal peptide.     

Lactoferrin and albumin in human pancreatic juice

Lactoferrin and albumin concentrations in pure pancreatic juice were studied by radial immunodiffusion in 81 patients. Lactoferrin concentration (% of total protein) was specifically increased in patients suffering from chronic calcifying pancreatitis (mean ±SE: 0.169±0.024) and no overlap was observed with patients suffering from other pancreatic diseases (0.008±0.001), organic nonpancreatic diseases (0.011±0.001) and without organic disease (0.01±0.001). Lactoferrin concentration was not found to be correlated with chronic alcohol consumption or pancreatic insufficiency. Albumin concentration (% of total protein) was increased in patients suffering from chronic calcifying pancreatitis (5.55±0.49) and other pancreatic diseases (5.45±1.02). These values were significantly higher (P<0.001) than the corresponding values in patients with organic nonpancreatic diseases (1.66±0.16) and patients without organic diseases (1.46±0.22). Measuring lactoferrin and albumin in pancreatic juice may aid in the diagnosis of pancreatic disease and in the differentiation of chronic calcifying pancreatitis, even in the earliest stage, from other pancreatic diseases such as pancreatic carcinoma or acute pancreatitis.     

Protein content of precipitates present in pancreatic juice of alcoholic subjects and patients with chronic calcifying pancreatitis

Chronic calcifying pancreatitis is characterized by the formation of intraductal protein plugs or precipitates and calcified stones in ducts. Similar precipitates may be collected by endoscopic retrograde catheterization of the main pancreatic duct. They are present in the pancreatic juice of alcoholic subjects and patients with chronic calcifying pancreatitis. Protein analysis of these precipitates was performed to try to elucidate the mechanism of stone formation. Two protein fraction were separated by extraction of precipitates. One fraction was easily soluble in saline and contained a small amount of most of the proteins of pancreatic juice. The other fraction was soluble in citrate or ethylenediaminetetraacetate and contained a few proteins with close isoelectric points and identical molecular weight (13,500). These proteins showed immunological identity with the "stone protein" isolated from human pancreatic calculi. Our data demonstrate that the major citrate-soluble protein of precipitates in pancreatic juice is identical with "stone protein". They are strongly support the concept that this protein is the organic matrix of pancreatic stones. Different mechanisms are proposed to explain the phenomenon of protein precipitation that frequently occurs in alcoholic subjects and patients with chronic calcifying pancreatitis.     

Pancreatic stone protein. II. Implication in stone formation during the course of chronic calcifying pancreatitis

Pancreatic stone protein, a novel protein isolated from pancreatic stones of patients suffering from chronic calcifying pancreatitis and secreted in normal human pancreatic juice, was measured by radial immunodiffusion in pure pancreatic juice. Patients with chronic calcifying pancreatitis of different etiologies had significantly lower levels of pancreatic stone protein when compared with other pancreatic diseases and controls. Pancreatic stone protein suppresses in vitro calcium carbonate precipitation and therefore stabilizes normally supersaturated pancreatic juice. The decreased pancreatic stone protein levels observed could be a key factor in the growth of calcium carbonate crystals and stone development during the course of chronic calcifying pancreatitis.     

Serum pancreatic stone protein in pancreatic diseases

Summary Serum pancreatic stone protein (PSP) was determined in sera of pancreatic and nonpancreatic diseases using enzyme immunoassay specific to human PSP to study the diagnostic and pathophysiological significance of PSP. Serum PSP in acute pancreatitis (mean±SD=1075.4±2849.1 ng/mL,n=33) was significantly higher than that in controls (78.6±31.8 ng/mL,n=37,p<0.01), chronic pancreatitis (156.8±82.8 ng/mL,n=32,p<0.05), and pancreatic cancer (148.468.8 ng/mL,n=26,p<0.05). No significant difference was found between noncalcified and calcified chronic pancreatitis. Serum PSP levels were significantly higher in chronic renal failure under hemodialysis (1796.0±1492.9 ng/mL) than in other diseases such as peptic ulcer, liver cirrhosis, gallstone, and diabetes mellitus. Low but significant correlation was obtained between serum PSP and serum immunoreactive trypsin (r=0.22,p<0.05). Increased serum PSP levels in acute pancreatitis and chronic renal failure suggest that serum PSP levels reflect reflux from pancreatic secretion, release from damaged pancreatic acinar cells, or retention in circulation, and can be useful for diagnosis of acute pancreatitis, but not chronic calcified pancreatitis.     

Fecal pancreatic elastase: a reproducible marker for severe exocrine pancreatic insufficiency

Background In order to apply fecal pancreatic elastase for follow-up of exocrine pancreatic function in chronic pancreatitis and cystic fibrosis, we examined the sensitivity, specificity, and long-term variability of a new polyclonal antibody-based enzyme-linked immunosorbent assay (ELISA). Methods Patients with definite chronic pancreatitis (n = 23), probable or possible chronic pancreatitis (n = 14), autoimmune pancreatitis (n = 7), or acute pancreatitis (n = 11), and 51 healthy subjects and 11 healthy infants participated in this study. Pancreatic function was graded as normal (n = 3), mild (n = 18), moderate (n = 9), or severe (n = 18) exocrine insufficiency on the basis of secretin tests. Fecal pancreatic elastase was measured by a new ELISA. Results Fecal pancreatic elastase concentration in control subjects varied widely, with a median of 478 μg/g. The specificity of this test was 90.2% with a cutoff value of >200 μg/g. The sensitivities were 60.9% for detecting definite chronic pancreatitis, 76.5% for calcifying pancreatitis, 71.4% for autoimmune pancreatitis, and 7.1% for probable or possible chronic pancreatitis. The sensitivities were 16.7% for mild, 12.5% for moderate, and 72.2% for severe exocrine pancreatic insufficiency. Forty patients were reexamined after a median interval of 347 days. The fecal pancreatic elastase levels between the first and second tests were not significantly different. Two infants, 4.5 and 5 months old, had abnormally low values, but after a median of 304 days all infants showed normal levels (median, 444 μg/g). Conclusions Fecal pancreatic elastase is a reproducible marker for severe exocrine pancreatic insufficiency. This test is valuable for longitudinal follow-up of exocrine pancreatic function.     

Serum immunoreactive elastase: is it useful for the diagnosis of pancreatic cancer?

We have measured serum immunoreactive pancreatic elastase 1 concentrations in 90 patients with pancreatic cancer in order to determine its usefulness in the diagnosis of this tumor. Abnormal elastase 1 concentrations were found in only 58 (64.4%) of the 90 patients. Fifty (55.5%) had abnormally high values, and eight (8.9%) had abnormally low values. No significant differences in elastase 1 levels were observed between patients with resectable cancer (n = 15) and those with unresectable cancer (n = 75). Moreover, no significant differences were found between elastase 1 concentrations of patients with pancreatic cancer and those of 71 patients with chronic pancreatitis. We conclude that serum elastase 1 measurement does not represent a significant advance in the diagnosis, whether early or late, of pancreatic cancer.     

Comparison of tumor marker CA 242 with CA 19-9 and carcinoembryonic antigen (CEA) in pancreatic cancer

BACKGROUND/AIMS: Although there are a variety of tumor markers used for diagnosis of pancreatic carcinoma, the sensitivity and specificity of those markers have not yet reached an ideal level. The aim of this study was to compare the diagnostic value of CA 242 with CA 19-9 and CEA in the patients with pancreatic cancer. METHODOLOGY: Serum CA 242, CA 19-9 and CEA levels were determined in 135 subjects in the following groups: Pancreatic cancer (n = 40), cholangiocellular carcinoma (n = 15), hepatocellular carcinoma (n = 10), cirrhosis (n = 7), chronic active hepatitis (n = 7), choledochal stone (n = 12), chronic pancreatitis (n = 9), acute pancreatitis (n = 6), and healthy controls (n = 29). RESULTS: An elevated serum CA 242 concentration (> 20 U/mL) was found in 30 out of 40 (70%) (mean; 2163 +/- 838 U/mL) patients with pancreas cancer, in 11 out of 15 patients with cholangiocellular carcinoma (93.3%) (mean 916 +/- 529 U/mL), in none of patients with hepatocellular carcinoma and healthy controls. Slightly elevated CA 242 concentration was found in 6 out of 41 patients with benign hepatobiliary and pancreatic disease (range 0.4-97.8 U/mL) (1 acute pancreatitis, 2 chronic pancreatitis, 1 cirrhosis, 2 choledochal stone). Mean serum CA 242, CA 19-9 and CEA levels of the pancreas cancer group were significantly higher than those of the other groups except the cholangiocellular carcinoma group. There was no significant difference between the stage of pancreas cancer regarding mean serum CA 242, CA 19-9 and CEA level. There was positive correlation between serum CA 242 and CA 19-9 level. In the pancreas cancer, the sensitivity of CA 242, CA 19-9 and CEA was 75%, 80%, 40%, respectively and the specificity of those markers was 85.5%, 67.5% and 73%, respectively. CONCLUSIONS: In conclusion, the advantage of CA 242 compared to CA 19-9 is that its specificity is higher than that of CA 19-9 in the diagnosis of pancreas cancer.     

Serum cathodic trypsin-like immunoreactivity, pancreatic lipase, and pancreatic isoamylase as diagnostic tests of chronic pancreatitis or pancreatic steatorrhea

We compared serum concentrations of cathodic trypsin-like immunoreactivity, pancreatic lipase, and pancreatic isoamylase as diagnostic tests of chronic pancreatitis (and of pancreatic steatorrhea in the 41 patients with steatorrhea) in 105 patients (57 men, 48 women) consecutively investigated because of clinical suspicion of chronic pancreatitis. Chronic pancreatitis (36 patients), pancreatic steatorrhea (24 patients), and other diseases were diagnosed without knowledge of the serum levels of the three enzymes. When evaluated by means of receiver operating characteristic curves, no differences were found in diagnostic performance of the enzymes with regard to chronic pancreatitis or pancreatic steatorrhea. The sensitivity and specificity for recognition of chronic pancreatitis ranged from 0.306 to 0.444 and from 0.942 to 0.986 when the discrimination values were chosen to give highest efficiencies. The similar ranges for pancreatic steatorrhea were 0.500-0.708 and 0.882-0.941. In conclusion, none of the three enzymes had any advantage over the others as diagnostic tests of chronic pancreatitis or of pancreatic steatorrhea. Only positive test results have clinical importance because of the low sensitivities of the three enzymes.     

Organic matrix of pancreatic stones associated with nutritional pancreatitis

In recent studies performed on pancreatic stones from patients with alcoholic pancreatitis, a novel secretory protein was identified: the pancreatic stone protein (PSP Mr 14,000). This protein suppresses CaCO3 precipitation, and could therefore stabilize normally supersaturated pancreatic juice. Crystallographic analysis of stones from patients with nutritional pancreatitis (NP), as well as alcoholic pancreatitis (AP), revealed that the main constituent was calcite (CaCO3). In the present study, we investigated the organic matrix of NP stones. In the 14 cases studied, the organic matrix was rendered soluble after mineral dissolution with EDTA + citrate. Analysis of the isolated matrix revealed the presence of one major protein (Mr 14,000), and of a minor protein (Mr 30,000), which is in fact an aggregate form of the 14,000 Mr protein. Using PSP antibodies, complete immunological identity was found between PSP, the immunoreactive form of PSP present in nonactivated pancreatic juice, and the protein matrix of NP stones. Moreover, protein matrix of NP stones also inhibited the nucleation of CaCO3 crystal, and decreased their growth rate in vitro. The presence of PSP in all AP and NP stones suggests that it plays a key role in stone formation during the course of chronic pancreatitis. These results also suggest the existence of some pathophysiological links between these two apparently different etiological forms of calcifying pancreatitis.     

Multiparametric tumor marker (CA 19-9, CEA, AFP, POA) analyses of pancreatic juices and sera in pancreatic diseases

With respect to their diagnostic utility CA 19-9, CEA, AFP and POA were determined in pancreatic secretions and serum of patients suffering from pancreatic cancer (n = 76/55) or chronic pancreatitis (n = 79/45) and of controls (n = 81/42), respectively. While the determination of AFP and POA both in pancreatic secretions and serum does not permit a differential diagnosis, serum CEA (greater than 10 ng/ml) and CA 19-9 (greater than 50 U/ml) levels were indicative of pancreatic cancer in 30% and 83%, respectively, with a rate of false positive results of 5% and 8.5% confined to the chronic pancreatitis patients. A combination of tumor marker analyses, that is, serum CA 19-9 (greater than 50 U/ml) and pancreatic secretion CEA (greater than 70 ng/ml), proved to be positive in 92.9% of tumor patients with a maximum of 10.5% false positives. Likewise, values of serum CA 19-9 (greater than 50 U/ml) and serum CEA (greater than 10 ng/ml) were found in 85.8% of the pancreatic cancer patients with only 8.8% false positives, which were confined to the chronic pancreatitis patients. These results indicate the superiority of multiparametric tumor marker analyses for the diagnosis of pancreatic cancer, especially when including new monoclonal antibody defined tumor markers.     

Determination of CA 19-9 antigen in serum and pancreatic juice for differential diagnosis of pancreatic adenocarcinoma from chronic pancreatitis

Serum CA 19-9 levels were measured in 63 patients with ductal pancreatic adenocarcinoma and in 49 patients with chronic pancreatitis. Concentrations were abnormally high (greater than 40 U/ml) in 57 (90%) patients with cancer and only in 5 (10%) patients with chronic pancreatitis. All patients with falsely normal serum values had poorly differentiated carcinomas. Median CA 19-9 concentrations were progressively higher in patients with more advanced cancer. Fifteen of 16 (93%) patients with localized cancer has abnormal serum levels but only 5 (31%) of them had values greater than 120 U/ml, which was the highest score observed in patients with chronic pancreatitis. Pure pancreatic juice was obtained endoscopically from 23 patients with pancreatic cancer and from 20 with chronic pancreatitis. CA 19-9 concentrations in pancreatic juice were significantly higher in patients with cancer than in non-neoplastic patients. All 11 patients with resectable cancer investigated had a ratio of CA 19-9 to secretory protein concentration in pancreatic juice above the range of patients with chronic pancreatitis. We conclude that serum CA 19-9 determination is highly sensitive and specific for the differential diagnosis of pancreatic cancer versus chronic pancreatitis. However, moderately increased values (less than 120 U/ml), as seen in patients with localized pancreatic adenocarcinoma, are not conclusive for malignancy. The measurement of CA 19-9 to total protein ratio in pure pancreatic juice is proposed as an adjunctive, accurate diagnostic marker for early stages of pancreatic adenocarcinoma.     

Calcifying obstructive pancreatitis: a study of intraductal papillary mucinous neoplasm associated with pancreatic calcification.

BACKGROUND AND AIMS: We have observed intraductal papillary mucinous neoplasm (IPMN) associated with pancreatic calcification. The aim of this study is to describe the profile of IPMN associated with calcification and gain insights into the pathogenesis of calcification in IPMN. METHODS: We identified 10 patients with IPMN with pancreatic calcification, of whom 7 underwent pancreatic resection. We reviewed demographic data, history of previous pancreatitis, and radiological and histological features of these patients. RESULTS: In patients with IPMN with calcification (mean age, 65 +/- 12 yr; 50% men), a diagnosis of chronic calcifying pancreatitis was entertained in 5 of 10 patients; 2 patients had undergone previous endoscopic therapy for stone removal. There was no previous history of pancreatitis in 9 of 10 patients. Radiologically, calcifications were seen diffusely throughout the gland in 8 of 10 patients and interpreted as chronic calcific pancreatitis. Although 1 of the 7 patients who underwent resection had diffuse IPMN throughout the gland, 6 patients had IPMN confined to the head or uncinate process (mean size, 2.75 cm; range, 1.1-5 cm). Histologically, 6 of 7 IPMNs were adenomas, and 1 patient had invasive cancer. No patient had intratumoral calcification. All 7 patients had calcification within the main pancreatic duct and/or side branches, often within inspissated mucus. CONCLUSIONS: IPMN associated with pancreatic calcification can lead to misdiagnosis and inappropriate treatment for chronic calcifying pancreatitis. In the absence of intratumoral calcification or a previous history of long-standing chronic pancreatitis, calcification in IPMN likely represents a unique and hitherto unrecognized form of calcifying obstructive pancreatitis caused by prolonged partial obstruction of the pancreatic duct.     

Low serum testosterone/dihydrotestosterone ratio in patients with pancreatic carcinoma

Serum testosterone, its metabolite 5 alpha-dihydrotestosterone, and the testosterone/dihydrotestosterone ratio were investigated in 22 male patients with proven pancreatic cancer, and compared with values from male patients with chronic pancreatitis (n = 21) and with nonpancreatic gastrointestinal tumors (n = 19). Testosterone and the testosterone/dihydrotestosterone ratio were significantly lower (p less than 0.001) in the pancreatic cancer group when they were compared with the other two groups. There was no significant difference in the dihydrotestosterone values between cancer groups. A testosterone/dihydrotestosterone ratio of less than 5 clearly distinguished most of the patients (20/22) with cancer of the pancreas from those with other tumors or chronic pancreatitis. The results suggest an alteration in the serum androgen profile in these patients. Therefore, the testosterone/dihydrotestosterone ratio could be a useful marker in the diagnosis of pancreatic carcinoma in male patients.     

Secretory immunoglobulin A in pancreatic juice and pancreatic tissue of patients with chronic pancreatitis

Background—The predominace of secretory IgA(S-IgA) in intestinal secretions compared with blood is wellestablished, but concentrations of this protein in pancreatic juice andits origin, especially in chronic pancreatitis, are unknown.
Aims—To investigate the role of S-IgA in chronic pancreatitis.
Patients—Twenty one patients with chronicpancreatitis (group I), three patients with proven malignancies (groupII), and 12 patients without pancreatic disease (group III).
Methods—Pure human pancreatic juice was collectedendoscopically in four fractions after consecutive stimulation withsecretin and cholecystokinin (CCK). Samples were analysed for S-IgA,protein, trypsinogen, and proteolytic activity.
Results—The S-IgA level was significant increasedin fraction 1 of pancreatic juice of group I (1210 (1411) ng/ml)compared with controls (33 (70) ng/ml). Protein concentrations andtrypsinogen content were lower in group I than in the other groups.Proteolytic activity could be observed in 53% of all 133 pancreaticjuice samples, but in 87% of fraction 1. In pancreatic tissue of three patients with chronic pancreatitis both IgA and secretory component were detected by immunohistology. Expression of the secretory componentby human pancreatic epithelial cells was increased in patients withchronic pancreatitis compared with normal controls. The concentrationof S-IgA in pancreatic juice did not correlate with the serum S-IgAlevel. In contrast, serum levels of S-IgA were decreased in patientswith chronic pancreatitis.
Conclusion—There are high levels of S-IgA inhuman pancreatic juice following chronic inflammation and a protectiverole is suggested for this immunoglobulin.

Keywords:chronic pancreatitis; pancreatic juice; proteaseactivity; protease inhibitors; secretory IgA; immunohistochemistry

     

Pure pancreatic juice studies in normal subjects and patients with chronic pancreatitis

Pure pancreatic juice was obtained from within the pancreatic duct in 54 patients after endoscopic cannulation of the papilla of Vater. In all 20 normal subjects there was a brisk response to intravenous injections of GIH secretin in small dosage (1 and 4 CU). Peak bicarbonate concentrations occurred after a 4 CU stimulus, whereas volumes, and bicarbonate and protein outputs were greatest after 70 CU. Total protein and amylase concentrations were highest in the first specimens collected from each patient, and fell rapidly after stimulation. Plateau levels for all indices were achieved 10-20 minutes after starting infusions of secretin and pancreozymin. When normal patients and those with chronic pancreatitis were compared, there was considerable overlap in all indices (volume, bicarbonate and total protein concentrations) after bolus injections of secretin. Most patients with chronic pancreatitis achieved a peak bicarbonate concentration in excess of 100 mmol/l. The median concentrations were not significantly different from normal after any dose of secretin when pooled 10 minute samples were analysed. However there were significant differences in peak bicarbonate concentrations (after 1 and 4 CU, but not after 70 CU), when one minute samples were compared. There were also statistically significant differences in the median 10 minute responses for volume after 1 and 70 CU, for bicarbonate output after 1, 4, and 70 CU, and for protein output after 70 CU. The results of juice studies in patients believed to have early chronic pancreatitis did not differ significantly from those in normal subjects or those with chronic pancreatitis. Endoscopic duct cannulation cannot guarantee complete recovery of pancreatic secretions, and measurements of volume and output may be inaccurate. When standard biochemical indices are used, the diagnostic role of pure juice studies is limited; further research may reveal more specific disease markers.     

Trypsin and lactoferrin levels in pure pancreatic juice in patients with pancreatic disease.

Levels of immunoreactive trypsin were measured in pure pancreatic juice obtained endoscopically from 44 patients with suspected pancreatic disease. Patients with pancreatic cancer all had low trypsin concentrations (median 3.6 micrograms/ml, range 0.6--12.0), but those with chronic pancreatitis had very variable levels (median 14.2 micrograms/ml, range 3.2--76.8), showing a considerable overlap with patients without pancreatic disease (median 37.1 micrograms/ml, range 10.4--66.0). When levels of lactoferrin in pancreatic juice were measured, all patients with chronic pancreatitis were found to have much higher levels (all greater than 900 ng/ml) than control subjects or patients with pancreatic cancer (all less than 400 ng/ml). The combined measurement of trypsin and lactoferrin in pure pancreatic juice appeared to be more promising than any other currently available test for the separation of patients with pancreatic cancer from those with chronic pancreatitis.     

Lymphocyte subsets and HLA-DR expression in normal pancreas and chronic pancreatitis

In an attempt to study the mechanisms leading to fibrosis in chronic pancreatitis, an in situ immunohistochemical investigation of lymphocytes and of class II major histocompatibility complex expression (HLA-DR) by epithelial cells has been designed. Samples of normal pancreas (n = 8), chronic calcifying pancreatitis (n = 4), chronic obstructive pancreatitis (n = 6), and diffuse fibrosing pancreatitis (n = 6) have been studied. In normal pancreas, T-lymphocytes were rare and were located in the epithelial layer of pancreatic ducts and in the periductal connective tissue. Duct cells were constantly HLA-DR negative. In chronic calcifying pancreatitis and chronic obstructive pancreatitis, T cells were numerous and were located around ducts and in the spreading areas of fibrous septa. In chronic obstructive pancreatitis, the duct cells strongly expressed the HLA-DR antigen. In diffuse fibrosing pancreatitis, fibrous tissue was devoid of lymphocytes and duct cells never expressed the HLA class II antigen. These results suggest that lymphocytes are involved in the fibrosing process occurring in chronic calcifying pancreatitis and chronic obstructive pancreatitis but not in diffuse fibrosing pancreatitis. The significance of de novo expression of HLA-DR antigen by duct cells is discussed.     

Serum elastase 1 in inflammatory pancreatic and gastrointestinal diseases and in renal insufficiency. A comparison with other serum pancreatic enzymes

Serum elastase 1 has been evaluated in 115 patients with pancreatic and nonpancreatic gastrointestinal diseases and in 36 healthy controls. Increased serum elastase 1 values were found in all 27 patients with acute pancreatitis. If the diagnostic cutoff was established as the 2-fold increase above the upper normal range, sensitivity of elastase 1 (100%) was superior to pancreatic lipase (90%), immunoreactive trypsin (87%) and pancreatic amylase (78%). Specificity was 96% for elastase 1 at this cutoff. No distinction was possible between edematous and necrotizing acute pancreatitis on the basis of peak serum elastase 1 concentrations. Among 32 patients with chronic pancreatitis increased serum elastase 1 values were found in 22% and decreased values in 16% of patients, showing a striking parallelism to serum values of pancreatic lipase and immunoreactive trypsin. Specificity, established in controls and 49 patients with different gastrointestinal diseases, was 77% for elastase 1, 76% for immunoreactive trypsin, 83% for pancreatic lipase and 91% for pancreatic amylase. In addition, we investigated 21 patients with severe chronic renal diseases. In patients with renal insufficiency elastase was increased in 33%, comparable to the frequency of increased amylase and pancreatic amylase serum levels, whereas immunoreactive trypsin was increased in 95%. Immunoreactive trypsin showed a significant correlation to creatinin serum concentration, whereas the other enzymes did not.     

Serum elastase 1 in inflammatory pancreatic and gastrointestinal diseases and in renal insufficiency. A comparison with other serum pancreatic enzymes

Summary Serum elastase 1 has been evaluated in 115 patients with pancreatic and nonpancreatic gastrointestinal diseases and in 36 healthy controls. Increased serum elastase 1 values were found in all 27 patients with acute pancreatitis. If the diagnostic cutoff was established as the 2-fold increase above the upper normal range, sensitivity of elastase 1 (100%) was superior to pancreatic lipase (90%), immunoreactive trypsin (87%) and pancreatic amylase (78%). Specificity was 96% for elastase 1 at this cutoff. No distinction was possible between edematous and necrotizing acute pancreatitis on the basis of peak serum elastase 1 concentrations. Among 32 patients with chronic pancreatitis increased serum elastase 1 values were found in 22% and decreased values in 16% of patients, showing a striking parallelism to serum values of pancreatic lipase and immunoreactive trypsin. Specificity, established in controls and 49 patients with different gastrointestinal diseases, was 77% for elastase 1, 76% for immunoreactive trypsin, 83% for pancreatic lipase and 91% for pancreatic amylase. In addition, we investigated 21 patients with severe chronic renal diseases. In patients with renal insufficiency elastase was increased in 33%, comparable to the frequency of increased amylase and pancreatic amylase serum levels, whereas immunoreactive trypsin was increased in 95%. Immunoreactive trypsin showed a significant correlation to creatinin serum concentration, whereas the other enzymes did not.