Lactoferrin in pure pancreatic juice

Lactoferrin as assayed by a radial immunodiffusion technique was studied in pure pancreatic juice collected at endoscopic retrograde cholangiopancreatography from 23 patients with chronic pancreatitis, 12 with acute pancreatitis, 21 with pancreatic cancer, and 29 cases of nonpancreatic gastrointestinal disease. No clear difference between lactoferrin concentrations in the chronic pancreatitis patients and other groups was found. Moreover, most lactoferrin levels were below the limit of detection in our assay. In addition, lactoferrin total protein ratios did not appear to be of value in the differential diagnosis of chronic pancreatitis. These results seem to be in contrast to the findings of other authors, who measured lactoferrin in duodenal fluid--which is unreliable, in our opinion--or who mainly studied chronic pancreatitis patients and few other pancreatic diseases. Lactoferrin might well be a nonspecific marker for serious pancreatic inflammation.     

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.     

Plasma lactoferrin levels in patients with chronic calcifying pancreatitis

Lactoferrin is a nonenzymatic secretory protein of human pancreas specifically increased in the external pancreatic secretion of patients with chronic calcifying pancreatitis. The possibility of an elevated concentration of plasma lactoferrin level in these patients needed to be explored even if the low pancreatic concentration of the protein did not favor this hypothesis. As expected, no increase could be observed between the plasma lactoferrin level of 16 patients with chronic calcifying pancreatitis (131 +/- 15 micrograms/l), compared to 17 controls (166 +/- 11 micrograms/l) and 15 patients with different organic diseases (187 +/- 18 micrograms/l).     

Immunochemical characterization and quantitative distribution of pancreatic stone protein in sera and pancreatic secretions in pancreatic disorders.

A fluorometric immunoassay has been established to quantitate pancreatic stone protein providing a sensitivity for concentrations from 0.015 to 0.5 micrograms/mL. When concentrations of pancreatic stone protein were determined from pancreatic secretions obtained either from patients suffering from chronic pancreatitis (n = 31) [including the calcifying forms (n = 10)], pancreatic cancer (n = 22), or nonpancreatic diseases (n = 17), no significant differences were found. In contrast, increased concentrations were found in serum samples from patients with chronic (39/66) and acute pancreatitis (16/20) compared with control patients. The differences between these diagnostic groups and controls were highly significant (P less than 0.0001) and independent of pancreatic enzyme activity. Immunochemical analyses of serum pancreatic stone protein showed an isoelectric point (pH 9) similar to that reported for the pancreatic thread protein. With respect to recent communications, these data do not support the etiopathogenic role postulated for pancreatic stone protein in chronic pancreatitis and chronic calcifying pancreatitis by other investigators.     

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.     

Duodenal lactoferrin in patients with chronic pancreatitis and gastrointestinal diseases

Lactoferrin (LF), chymotrypsin and lipase activity were measured in duodenal juice during pancreatic stimulation. Secretin (0.5 CU/kg/h) plus cerulein (75 ng/kg/h) were infused intravenously in 98 subjects: 33 patients without organic diseases (C), 40 patients affected by chronic pancreatitis (CP), and 25 patients with different gastrointestinal diseases (GID). LF was determined by means of a new noncompetitive immunoenzymatic assay with a sensitivity in the duodenal juice of 5 ng/ml. Duodenal LF concentrations were significantly higher in CP than in C or GID (p less than 0.001). LF was in a normal range in acute relapsing pancreatitis due to biliary stones or pancreas divisum. In the diagnosis of the chronic pancreatitis, LF/lipase ratios showed a specificity of 93% and a sensitivity of 95%. Our results show that LF immunoassay in duodenal juice is a sensitive and accurate assay to apply in pancreatic function tests involving duodenal content analysis.     

Diagnosis of chronic pancreatitis by measurement of lactoferrin in duodenal juice.

Lactoferrin is a non-enzymatic secretory protein of human pancreas and is specifically increased in pancreatic juice of patients with chronic pancreatitis. Duodenal contents being easier to obtain than pure pancreatic juice, the possibility of using lactoferrin measurement in duodenal juice as a diagnosis test for chronic pancreatitis was explored. Forty-eight patients were studied. Duodenal juice was obtained devoid of salivary contamination by a special double lumen tube. Under these conditions lactoferrin secretion (concentration and output) is increased in patients with chronic pancreatitis. When expressed as the ratio of lactoferrin to lipase units, there was no overlap between chronic pancreatitis and other pancreatic disease or controls. The simplicity and the reproducibility of the technique on a material as readily available as duodenal juice confirms the diagnostic value of lactoferrin measurement in the assessment of patients with suspected pancreatic disease.     

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 and synovial type phospholipases A2 in serum samples from patients with severe acute pancreatitis.

Phospholipase A2 (PLA2) is the rate limiting enzyme in the formation of prostaglandins and probably plays a key part in the pathology of various inflammatory diseases. In acute pancreatitis, the catalytic activity of PLA2 in serum correlates with the severity of the disease. The cellular source of the catalytically active PLA2 in serum of patients suffering from acute pancreatitis and other diseases is unknown. Immunoassays for the measurement of pancreatic group I PLA2 and nonpancreatic synovial type group II PLA2 have recently been developed and the present study investigated the presence of group I and group II PLA2s in serum samples from 36 patients with severe acute pancreatitis. The catalytic activity of PLA2 showed a highly significant correlation with the concentration of synovial type PLA2 (r = 0.939, p = 0.001) but not with the concentration of pancreatic PLA2 (r = 0.067, p = 0.698). The results suggest that pancreatic PLA2 circulates mostly as inactive enzyme in patients with acute pancreatitis whereas synovial type PLA2 is responsible for the increased catalytic activity of the enzyme and thus might be associated with the pathophysiology of the disease.     

Clinical study of exocrine pancreatic function test by oral administration by N-benzoyl-L-tyrosyl-p-aminobenzoic acid

The clinical usefulness of a simple exocrine pancreatic function diagnostic test (PFT) was examined by the oral administration of 500 mg of N-benzoyl-L-tyrosyl-p-aminobenzoic acid. Recovery of p-aminobenzoic acid (PABA) in the urine was significantly lower in patients with calcifying chronic pancreatitis (58.6%) and noncalcifying chronic pancreatitis (68.6%) than in healthy normal subjects (81.0%; p less than 0.001 and p less than 0.05, respectively). Abnormally low values were demonstrated in 15 out of 19 (78.9%) chronic pancreatitis cases. In comparing the PFT with the pancreozymin secretin test, a good correlation (P less than 0.001) with maximum bicarbonate concentration was detected. In cases which were abnormal with respect to the PFT, the recovery rate of PABA was increased by the administration of antacids or digestive enzyme preparations (average increase of 24.1 or 29.8%, respectively). These results suggest that this test is also useful for the evaluation of therapeutic effects in patients with pancreatic diseases.     

Idiopathic chronic calcifying pancreatitis with diabetes mellitus

Summary We present a case of a 27-year-old female suffering from chronic calcifying pancreatitis with diabetes mellitus. Radiographic examinations and exocrine pancreatic function tests revealed considerable dilatation of pancreatic ducts with large intraductal calculi and exocrine pancreatic insufficiency, respectively. Recent literature indicates that a decrease in the activity of pancreatic stone protein (PSP), which inhibits CaCO₃ crystal formation in pancreatic juice, is closely related to the development of chronic calcifying pancreatitis. The patient had no apparent cause or family history of pancreatitis. We therefore investigated the possibility that alterations in the PSP gene might explain the chronic pancreatitis seen in this patient. Six exons of the PSP gene amplified by polymerase chain reaction were directly sequenced, but there was no apparent base mutation observed. Furthermore, Southern blot analysis revealed neither rearrangement nor deletion of the PSP gene in the genomic DNA of this case. However, this genetic approach will be useful for future study of the etiology of hereditary pancreatitis.     

Lactoferrin in Pure Pancreatic Juice in Chronic Pancreatitis

To investigate the role of lactoferrin in intraductal protein precipitates in chronic pancreatitis, lactoferrin was measured in pure pancreatic juice collected by endoscopic retrograde pancreatic cannulation using a sensitive and specific radioimmunoassay. Significant gradual increase in the lactoferrin concentration and output was observed in chronic pancreatitis (mean +/- SE = 1.13 +/- 0.04 microgram/ml, 1.61 +/- 0.44 microgram/min for five controls; 4.73 +/- 0.70 microgram/ml, 14.1 +/- 2.86 micrograms/min for 15 patients with noncalcified mild chronic pancreatitis; 23.6 +/- 4.7 micrograms/ml, 28.4 +/- 13.4 micrograms/min for four with chronic pancreatitis with visible protein plugs or calculi). The total protein in the juice gradually decreased in chronic pancreatitis (12.8 +/- 1.48 mg/ml for control, 7.6 +/- 1.37 for noncalcified, 5.2 +/- 1.27 for patients with plugs or calculi). Lactoferrin appears to rise as the disease progresses and although this may be important etiologically, it may also just be an accompanying protein which increases as the disease progresses.     

Total Cholesterol Level for Assessing Pancreatic Insufficiency Due to Chronic Pancreatitis

Background/Aims

To determine the nutritional markers important for assessing the degree of pancreatic insufficiency due to chronic pancreatitis in routine clinical practice.

Methods

A total of 137 patients with chronic pancreatitis were followed up for more than 1 year. They were divided into two groups: a pancreatic diabetes mellitus (DM) group, consisting of 47 patients undergoing medical treatment for DM of pancreatic origin, and a nonpancreatic DM group, consisting of 90 other patients (including 86 patients without DM). Serum albumin, prealbumin, total cholesterol, cholinesterase, magnesium, and hemoglobin were compared between the two groups.

Results

The total cholesterol was significantly lower in the pancreatic than the nonpancreatic DM group (164 mg/dL vs 183 mg/dL, respectively; p=0.0028). Cholinesterase was significantly lower in the former group (263 U/L vs 291 U/L, respectively; p=0.016). Among the 37 patients with nonalcoholic pancreatitis, there was no difference in the cholinesterase levels between the pancreatic and nonpancreatic (296 U/L vs 304 U/L, respectively; p=0.752) DM groups, although cholesterol levels remained lower in the former (165 mg/dL vs 187 mg/dL, respectively; p=0.052).

Conclusions

Cholinesterase levels are possibly affected by concomitant alcoholic liver injury. The total cholesterol level should be considered when assessing pancreatic insufficiency due to chronic pancreatitis.     

Lactoferrin in the duodenal juice of patients with chronic calcifying pancreatitis.

We have shown the presence of lactoferrin in the pancreatic juice of patients with chronic calcifying pancreatitis (CCP) and its absence in controls. In this work, lactoferrin has been found in saliva, but neither in gastric juice nor in bile. Therefore, a technique for collecting the human duodenal juice with a rubber tube and preventing its contamination with saliva is described. In the duodenal juice of 15 patients with CCP, 52 controls without evident pancreatic diseases, and 9 cases of pancreatic diseases other than CCP, lactoferrin has been searched for by immunological methods before and after an intravenous injection of CCK-PZ (3 U CHR) + secretin ( C U). The lactoferrin test in positive in 5, inconclusive in 6, and negative in 41 cases, and in the 9 cases of non-CCP pancreatic diseases it is negative. The use of this test in the diagnosis of CCP is proposed.     

Serum immunoreactive elastase in diagnosis of pancreatic diseases

Diagnostic significance of serum immunoreactive elastase-1 was studied in 137 patients with pancreatic disease, 335 with various nonpancreatic diseases, and 416 healthy controls by using radioimmunoassay. Frequency of abnormally high serum elastase values exceeding 410 ng/dl was 100% in acute pancreatitis (N=14), 40% in chronic pancreatitis (N=80), and 72% in pancreatic cancer (N=43). In pancreatic cancer the mean value of serum elastase in resectable cancer (N=19) was significantly higher than that in unresectable cancer (N=24). Sensitivity, specificity, and efficiency of serum elastase in pancreatic cancer were 72.1%, 98.3%, and 95.9% against healthy controls; 72.1%, 85.9%, and 83.6% against nonpancreatic digestive diseases; and 72.1%, 60.0%, and 64.2% against chronic pancreatitis at a cutoff level of 410 ng/dl, respectively. High serum elastase could be a diagnostic clue to detect pancreatic duct obstruction due to pancreatic cancer, although further examination should be done by endoscopic retrograde pancreatography and other imaging studies.This study was supported in part by a research grant for intractable pancreatic disease and a cancer grant 58-21 from Ministry of Health and Welfare, Japan.     

Lactoferrin secretion in alcoholic pancreatic disease

Lactoferrin, a nonenzyme protein normally secreted in small amounts in pancreatic juice, has been reported by several investigators to be secreted in large amounts in chronic pancreatitis. Whether this increased secretion first occurs at an early or late stage of alcoholic pancreatic disease is unknown. In this study we measured lactoferrin and enzyme outputs in duodenal juice from 10 healthy subjects and three groups of alcoholic subjects: asymptomatic chronic alcoholics without evidence, clinically or biochemically, of pancreatitis (10), those recovered from acute pancreatitis (8), and those with established chronic pancreatitis (8). A multilumen, marker-perfused duodenal catheter was used to aspirate basal pancreatic secretions at the ligament of Treitz. The mean ( +/-SE) lactoferrin concentration in duodenal juice for the four groups of subjects was: healthy, 0.7 +/- 0.1 micrograms/ml; asymptomatic alcoholics, 5.5 +/- 1.5 micrograms/ml; alcoholics who had recovered from acute pancreatitis, 7.4 +/- 0.8 micrograms/ml; and alcoholics with chronic pancreatitis 7.1 +/- 1.9 micrograms/ml. The three groups of alcoholics each had a greater lactoferrin concentration than the normals (P less than 0.005). The output of lactoferrin in the four groups paralleled the concentration in that the three groups of alcoholics had a significantly greater output: healthy subjects, 3.4 +/- 0.5 micrograms/kg/hr; asymptomatic alcoholics, 25.7 +/- 7.4 micrograms/kg/hr; alcoholics recovered from acute pancreatitis, 80.1 +/- 27 micrograms/kg/hr; and alcoholics with chronic pancreatitis, 90.9 +/- 32 micrograms/kg/hr. The output of chymotrypsin and trypsin in the four groups of subjects revealed increased secretory rates in the asymptomatic alcoholics and the alcoholics recovered from acute pancreatitis.(ABSTRACT TRUNCATED AT 250 WORDS)     

Enzyme immunoassay for serum pancreatic lipase in the diagnosis of pancreatic diseases

To evaluate the diagnostic utility of serum immunoreactive lipase (IRL), serum lipase was determined using an enzyme immunoassay and a turbidimetric method along with total serum amylase in 41 healthy controls, 76 patients with pancreatic disease and 60 with nonpancreatic disease. Serum IRL was elevated in 12 of 13 patients with acute pancreatitis, 12 of 44 with chronic pancreatitis and in 12 of 19 with pancreatic cancer. The IRL was low in 9 of the 44 patients with chronic pancreatitis, which coincided with advanced exocrine pancreatic insufficiency. Overall sensitivities in pancreatic diseases were 59% for serum IRL, 38% for turbidimetric lipase and 51% for amylase, specificities in healthy controls and nonpancreatic diseases were 80% for serum IRL, 86% for turbidimetric lipase and 88% for serum amylase. Serum IRL determination is useful for diagnosis in pancreatic diseases when compared with the conventional determination of serum lipase.     

Pancreolauryl Test for Pancreatic Exocrine Insufficiency

Pancreolauryl test (PLT), a tubeless pancreatic function test, was performed in 40 consecutive patients suffering from chronic pancreatitis, in 21 patients with miscellaneous digestive diseases, and in 18 control subjects to assess its diagnostic sensitivity and specificity. N-benzoyl- l -tyrosyl- p -aminobenzoic acid test (PABA test) and sccretin-cerulein test were also carried out to compare the diagnostic value of PLT with that of these two pancreatic function tests. PLT was abnormal in 22 of 40 patients with chronic pancreatitis (55%). In particular, pathological results were found in all patients with severe pancreatic insufficiency and only in four of 14 patients with mild to moderate insuffieiency. PABA test showed a slightly lower sensitivity in severe insufficiency, and the same sensitivity in mild-moderate insufficiency. PLT was normal in ail control subjects and in 17 of 21 patients with nonpancreatic digestive diseases. Its specificity (90%) was slightly higher than that of PABA test (82%). The results indicate that PLT may be used to support a diagnosis of severe panereatic exocrine insufficiency, while in mild or moderate insufficiency its diagnostic value is limited.     

Do cytokine concentrations in pancreatic juice predict the presence of pancreatic diseases?

BACKGROUND & AIMS: Cytokine concentration in pancreatic juice of patients with pancreatic disease is unknown. Secretin stimulation allows endoscopic collection of pancreatic juice secreted into the duodenum. We aimed to evaluate the cytokine concentrations in pancreatic juice of patients with abdominal pain to discriminate presence from absence of pancreatic disease. METHODS: From January 2003-December 2004, consecutive patients with abdominal pain compatible with pancreatic origin were enrolled. Patients underwent upper endoscopy. Intravenous secretin (0.2 mug/kg) was given immediately before scope intubation. Pancreatic juice collected from the duodenum was immediately snap-frozen in liquid nitrogen until assays were performed. Pancreatic juice levels of interleukin-8, interleukin-6, intercellular adhesion molecule 1, and transforming growth factor-beta 1 were measured by modified enzyme-linked immunosorbent assays. The final diagnosis was made by the primary gastroenterologist on the basis of medical history; laboratory, endoscopic, and imaging studies; and clinical follow-up. Fisher exact test and Kruskal-Wallis rank sum test were used for statistical analysis. RESULTS: Of 130 patients screened, 118 met the inclusion criteria. Multivariate analysis revealed that only interleukin-8 was able to discriminate between normal pancreas and chronic pancreatitis (P = .011), pancreatic cancer (P = .044), and the presence of pancreatic diseases (P = .007). Individual cytokine concentrations were not significantly different in chronic pancreatitis compared with pancreatic cancer. CONCLUSIONS: Cytokine levels can be measured in pancreatic juice obtained from the duodenum without direct cannulation of the pancreatic duct. Interleukin-8 concentration in pancreatic juice can be used to discriminate between normal pancreas and patients with pancreatic disease. This is a relatively simple and noninvasive method to aid in the diagnosis of pancreatic diseases.     

Increased concentrations of synovial-type phospholipase A2 in serum and pulmonary and renal complications in acute pancreatitis.

The most important fatal complications of acute pancreatitis are respiratory dysfunction and anuria. Phospholipase A2 has been postulated to be associated with pathologies of various diseases, such as acute pancreatitis, septic shock and multiple injuries. We have recently developed immunoassays for the measurement of pancreatic and nonpancreatic synovial-type phospholipase A2. The present prospective study on 35 consecutive patients with acute pancreatitis indicated that the concentration of synovial-type phospholipase A2, the catalytic activity of phospholipase A2 and the concentration of C-reactive protein in serum were significantly higher in those patients suffering from acute pancreatitis who needed respirator treatment than in those who managed with spontaneous breathing, while there was no difference between these groups in the concentration of pancreatic phospholipase A2. The only significant difference between patients whose highest creatinine concentration rose up to 140 mumol/l and those whose highest creatinine concentration remained below this cutoff value was in their synovial-type phospholipase A2 values. The increased concentration of nonpancreatic synovial-type phospholipase A2 in serum was associated with pulmonary and renal complications. These results emphasize the role of synovial-type phospholipase A2 in the pathophysiology of acute pancreatitis.