Increased serum trypsinogen 2 and trypsin 2-alpha 1 antitrypsin complex values identify endoscopic retrograde cholangiopancreatography induced pancreatitis with high accuracy

Combination Topical Epinephrine and Non-steroidal Inflammatory Drugs in the Prevention of Post-ERCP Pancreatitis: A Systematic Review

BACKGROUND

The utility of combination rectal NSAID and topical epinephrine (EI) or rectal NSAID and normal saline (SI) sprayed on duodenal papilla in the prevention of post-ERCP pancreatitis (PEP) has been studied but results have been conflicting.

AIMS

To evaluate the benefit of using combination prophylaxis in preventing PEP.

METHODS

A literature search was performed using Scopus, PubMed/MEDLINE, and Cochrane databases in May 2021. Randomized controlled trials (RCTs) involving adults patients who underwent ERCP and received EI versus SI were eligible for inclusion. The pooled effect was expressed as odds ratio (OR) to assess the rate of PEP, severity of PEP, and specific adverse events. The results were pooled using Reviewer Manager 5.4 software.

RESULTS

Six RCTs involving 4016 patients were included in the final analysis. The EI group did not demonstrate any significant benefit over SI group in preventing PEP (OR = 1.00, 95% CI [0.68, 1.45], P = 0.98), irrespective of gender or the epinephrine concentration used. The tests for subgroup differences were not statistically significant with P-values of 0.66 and 0.28, respectively. The addition of topical epinephrine to rectal NSAID did not improve the rate of moderate to severe PEP (OR = 0.94, P = 0.86) or PEP in high-risk patients (OR = 1.14, 95%, P = 0.73). The rates of infection, including cholangitis and sepsis (OR = 0.63, P = 0.07), gastrointestinal bleeding (OR = 1.25, P = 0.56) and procedure-related death (OR = 0.71, P = 0.59) were similar between both groups.

CONCLUSION

The addition of topical epinephrine did not demonstrate any benefit over rectal NSAID alone in preventing PEP or reducing other procedure-related adverse events.

Randomized trial of high-dose rectal diclofenac suppository and epinephrine spray on duodenal papilla for prevention of post-endoscopic retrograde cholangiopancreatography pancreatitis

BACKGROUND AND AIMS

High-dose rectal diclofenac suppository and epinephrine spray on duodenal papilla during endoscopic retrograde cholangiopancreatography (ERCP) may reduce the incidence of post-ERCP pancreatitis. We performed randomized trial to compare the effect of combination of rectal diclofenac and epinephrine spray on papilla (group A) vs. combination of rectal diclofenac with saline spray (group B) for prevention of post-ERCP pancreatitis.

METHODS

We performed a double-blind trial at tertiary care center from April 2018 to May 2020 on 882 patients with naive papilla undergoing ERCP. The patients were randomly assigned to groups, A (n=437) or B (n=445). All patients received a single dose of rectal diclofenac 100 mg within 30 minutes before ERCP; 20 mL of diluted epinephrine 0.02% (group A) or saline (group B) was then sprayed on the duodenal papilla at the end of ERCP. The primary outcome was to compare incidence of post-ERCP pancreatitis (PEP) in two groups.

RESULTS

The groups had similar baseline characteristics. PEP developed in 28 patients in group A (6.4%) and 35 patients in group B (7.9%) (relative risk, 1.1; 95% CI, 0.87-1.39; p=0.401).

CONCLUSION

Our study showed that addition of epinephrine spray on duodenal papilla did not reduce the risk of post-ERCP pancreatitis. There is need for further studies to evaluate the role of different concentrations of epinephrine spray on papilla for prevention of post-ERCP pancreatitis.

TRIAL REGISTRATION

Clinical Trials Registry- India (CTRI/2018/04/013396).

The Polymorphisms at PRSS1-PRSS2 and MORC4 Loci and the Risk of Post-ERCP Pancreatitis

Background and Aim

The risks of post-ERCP pancreatitis (PEP) are identified as patient- and procedure-related factors. However, the genetic contribution for PEP is still unclear. Recent data show that the polymorphisms of PRSS1-PRSS2 (rs10273639) and MORC4 (rs12688220) are associated with recurrent acute pancreatitis and chronic pancreatitis. We aim to evaluate the association between these polymorphisms and post-ERCP pancreatitis in order to improve better prognosis and better care for these patients.

Methods

This is a retrospective, case-control study which includes 49 cases and 97 controls that are age-, procedure-, and risk of PEP-matched with the cases in 1 : 2 fashion. The PEP was diagnosed and graded for severity according to the standard consensus, and the risk factors of PEP were identified according to the ESGE guideline. Polymorphisms at rs10273639 and rs12688220 were evaluated by TaqMan technique and were identified in 133 (40 cases and 93 controls) and 146 patients, respectively.

Results

The demographic data between 2 groups are not significantly different. The genotype frequencies of PRSS1-PRSS2 (TT, TC, and CC) are 26, 13, and 1 vs. 67, 25, and 1 in cases and controls, respectively (p = 0.642). The genotype frequencies of MORC4 in female (TT, TC, and CC) are 8, 23, and 5 vs. 12, 26, and 21 in cases and controls, respectively (p = 0.071). The genotype frequencies of MORC4 in male (T and C) are 5 and 8 vs. 21 and 17 in cases and controls, respectively (p = 0.468). The allelic frequencies of MORC4 in combination of both genders (T, C) are 44 and 41 vs. 71 and 84 in cases and control, respectively (p = 0.431). In PEP cases, the allelic frequencies of PRSS1-PRSS2 (T and C) are 59 and 13 vs. 6 and 2 in mild and moderate/severe cases, respectively (p = 0.633). The allelic frequencies of MORC4 (T and C) are 38 and 39 vs. 4 and 4 in mild and moderate/severe cases, respectively (p = 0.972).

Conclusion

Polymorphisms at PRSS1-PRSS2 and MORC4 are not associated with the risk or severity of post-ERCP pancreatitis.

An immunocapture-LC-MS-based assay for serum SPINK1 allows simultaneous quantification and detection of SPINK1 variants

Pancreatic secretory trypsin inhibitor Kazal type 1 (SPINK1) is a 6420 Da peptide produced by the pancreas, but also by several other tissues and many tumors. Some mutations of the SPINK1 gene, like the one causing amino acid change N34S, have been shown to confer susceptibility to recurrent or chronic pancreatitis. Detection of such variants are therefore of clinical utility. So far SPINK1 variants have been determined by DNA techniques. We have developed and validated an immunocapture-liquid chromatography-mass spectrometric (IC-LC-MS) assay for the detection and quantification of serum SPINK1, N34S-SPINK1, and P55S-SPINK1. We compared this method with a time-resolved immunofluorometric assay (TR-IFMA) for serum samples and primer extension analysis of DNA samples. We used serum and DNA samples from patients with acute pancreatitis, renal cell carcinoma, or benign urological conditions. With the help of a zygosity score calculated from the respective peak areas using the formula wild-type (wt) SPINK1/(variant SPINK1 + wt SPINK1), we were able to correctly characterize the heterozygotes and homozygotes from the samples with DNA information. The score was then used to characterize the apparent zygosity of the samples with no DNA characterization. The IC-LC-MS method for SPINK1 was linear over the concentration range 0.5-1000 μg/L. The limit of quantitation (LOQ) was 0.5 μg/L. The IC-LC-MS and the TR-IFMA assays showed good correlation. The median zygosity score was 1.00 (95% CI 0.98-1.01, n = 11), 0.55 (95% CI 0.43-0.61, n = 14), and 0.05 (range 0.04-0.07, n = 3) for individuals found to be wt, heterozygous, and homozygous, respectively, for the N34S-SPINK1 variant by DNA analysis. When DNA samples are not available, this assay facilitates identification of the N34S- and P55S-SPINK1 variants also in archival serum samples.

Serum amylase and lipase and urinary trypsinogen and amylase for diagnosis of acute pancreatitis

BACKGROUND

The treatment of people with acute abdominal pain differs if they have acute pancreatitis. It is important to know the diagnostic accuracy of serum amylase, serum lipase, urinary trypsinogen-2, and urinary amylase for the diagnosis of acute pancreatitis, so that an informed decision can be made as to whether the person with abdominal pain has acute pancreatitis. There is currently no Cochrane review of the diagnostic test accuracy of serum amylase, serum lipase, urinary trypsinogen-2, and urinary amylase for the diagnosis of acute pancreatitis.

OBJECTIVES

To compare the diagnostic accuracy of serum amylase, serum lipase, urinary trypsinogen-2, and urinary amylase, either alone or in combination, in the diagnosis of acute pancreatitis in people with acute onset of a persistent, severe epigastric pain or diffuse abdominal pain.

SEARCH METHODS

We searched MEDLINE, Embase, Science Citation Index Expanded, National Institute for Health Research (NIHR HTA and DARE), and other databases until March 2017. We searched the references of the included studies to identify additional studies. We did not restrict studies based on language or publication status, or whether data were collected prospectively or retrospectively. We also performed a 'related search' and 'citing reference' search in MEDLINE and Embase.

SELECTION CRITERIA

We included all studies that evaluated the diagnostic test accuracy of serum amylase, serum lipase, urinary trypsinogen-2, and urinary amylase for the diagnosis of acute pancreatitis. We excluded case-control studies because these studies are prone to bias. We accepted any of the following reference standards: biopsy, consensus conference definition, radiological features of acute pancreatitis, diagnosis of acute pancreatitis during laparotomy or autopsy, and organ failure. At least two review authors independently searched and screened the references located by the search to identify relevant studies.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data from the included studies. The thresholds used for the diagnosis of acute pancreatitis varied in the trials, resulting in sparse data for each index test. Because of sparse data, we used -2 log likelihood values to determine which model to use for meta-analysis. We calculated and reported the sensitivity, specificity, post-test probability of a positive and negative index test along with 95% confidence interval (CI) for each cutoff, but have reported only the results of the recommended cutoff of three times normal for serum amylase and serum lipase, and the manufacturer-recommended cutoff of 50 mg/mL for urinary trypsinogen-2 in the abstract.

MAIN RESULTS

Ten studies including 5056 participants met the inclusion criteria for this review and assessed the diagnostic accuracy of the index tests in people presenting to the emergency department with acute abdominal pain. The risk of bias was unclear or high for all of the included studies. The study that contributed approximately two-thirds of the participants included in this review was excluded from the results of the analysis presented below due to major concerns about the participants included in the study. We have presented only the results where at least two studies were included in the analysis.Serum amylase, serum lipase, and urinary trypsinogen-2 at the standard threshold levels of more than three times normal for serum amylase and serum lipase, and a threshold of 50 ng/mL for urinary trypsinogen-2 appear to have similar sensitivities (0.72 (95% CI 0.59 to 0.82); 0.79 (95% CI 0.54 to 0.92); and 0.72 (95% CI 0.56 to 0.84), respectively) and specificities (0.93 (95% CI 0.66 to 0.99); 0.89 (95% CI 0.46 to 0.99); and 0.90 (95% CI 0.85 to 0.93), respectively). At the median prevalence of 22.6% of acute pancreatitis in the studies, out of 100 people with positive test, serum amylase (more than three times normal), serum lipase (more than three times normal), and urinary trypsinogen (more than 50 ng/mL), 74 (95% CI 33 to 94); 68 (95% CI 21 to 94); and 67 (95% CI 57 to 76) people have acute pancreatitis, respectively; out of 100 people with negative test, serum amylase (more than three times normal), serum lipase (more than three times normal), and urinary trypsinogen (more than 50 ng/mL), 8 (95% CI 5 to 12); 7 (95% CI 3 to 15); and 8 (95% CI 5 to 13) people have acute pancreatitis, respectively. We were not able to compare these tests formally because of sparse data.

AUTHORS' CONCLUSIONS

As about a quarter of people with acute pancreatitis fail to be diagnosed as having acute pancreatitis with the evaluated tests, one should have a low threshold to admit the patient and treat them for acute pancreatitis if the symptoms are suggestive of acute pancreatitis, even if these tests are normal. About 1 in 10 patients without acute pancreatitis may be wrongly diagnosed as having acute pancreatitis with these tests, therefore it is important to consider other conditions that require urgent surgical intervention, such as perforated viscus, even if these tests are abnormal.The diagnostic performance of these tests decreases even further with the progression of time, and one should have an even lower threshold to perform additional investigations if the symptoms are suggestive of acute pancreatitis.

Role of Biomarkers in Diagnosis and Prognostic Evaluation of Acute Pancreatitis

Acute pancreatitis is a potentially life threatening disease. The spectrum of severity of the illness ranges from mild self-limiting disease to a highly fatal severe necrotizing pancreatitis. Despite intensive research and improved patient care, overall mortality still remains high, reaching up to 30–40% in cases with infected pancreatic necrosis. Although little is known about the exact pathogenesis, it has been widely accepted that premature activation of digestive enzymes within the pancreatic acinar cell is the trigger that leads to autodigestion of pancreatic tissue which is followed by infiltration and activation of leukocytes. Extensive research has been done over the past few decades regarding their role in diagnosis and prognostic evaluation of severe acute pancreatitis. Although many standalone biochemical markers have been studied for early assessment of severity, C-reactive protein still remains the most frequently used along with Interleukin-6. In this review we have discussed briefly the pathogenesis and the role of different biochemical markers in the diagnosis and severity evaluation in acute pancreatitis.

Is ESR Important for Predicting Post-ERCP Pancreatitis?

BACKGROUND

Pancreatitis remains the most common complication of endoscopic retrograde cholangiopancreatography (ERCP), resulting in substantial morbidity and occasional mortality. There are notable controversies and conflicting reports about risk factors of post-ERCP pancreatitis (PEP).

AIM

To evaluate the potential risk factors for PEP at a referral tertiary center, as a sample of the Iranian population.

MATERIALS AND METHODS

Baseline characteristics and clinical as well as paraclinical information of 780 patients undergoing diagnostic and therapeutic ERCP at Taleghani hospital in Tehran between 2008 and 2012 were reviewed. Data were collected prior to the ERCP, at the time of the procedure, and 24-72 hours after discharge. PEP was diagnosed according to consensus criteria.

RESULTS

Of the 780 patients who underwent diagnostic ERCP, pancreatitis developed in 26 patients (3.3%). In the multivariable risk model, significant risk factors with adjusted odds ratios (ORs) were age <65 years (OR = 10.647, P = 0.023) and erythrocyte sedimentation rate (ESR) >30 (OR = 6.414, P < 0.001). Female gender, history of recurrent pancreatitis, pre-ERCP hyperamylasemia, and difficult or failed cannulation could not predict PEP. There was no significant difference in the rate of PEP in wire-guided cannulation versus biliary cannulation using a sphincterotome and contrast injection as the conventional method.

CONCLUSIONS

Performing ERCP may be safer in the elderly. Patients with high ESR may be at greater risk of PEP, which warrants close observation of these patients for signs of pancreatitis after ERCP.

Loss of cftr function leads to pancreatic destruction in larval zebrafish

The development and function of many internal organs requires precisely regulated fluid secretion. A key regulator of vertebrate fluid secretion is an anion channel, the cystic fibrosis transmembrane conductance regulator (CFTR). Loss of CFTR function leads to defects in fluid transport and cystic fibrosis (CF), a complex disease characterized by a loss of fluid secretion and mucus buildup in many organs including the lungs, liver, and pancreas. Several animal models including mouse, ferret and pig have been generated to investigate the pathophysiology of CF. However, these models have limited accessibility to early processes in the development of CF and are not amenable for forward genetic or chemical screens. Here, we show that Cftr is expressed and localized to the apical membrane of the zebrafish pancreatic duct and that loss of cftr function leads to destruction of the exocrine pancreas and a cystic fibrosis phenotype that mirrors human disease. Our analyses reveal that the cftr mutant pancreas initially develops normally, then rapidly loses pancreatic tissue during larval life, reflecting pancreatic disease in CF. Altogether, we demonstrate that the cftr mutant zebrafish is a powerful new model for pancreatitis and pancreatic destruction in CF. This accessible model will allow more detailed investigation into the mechanisms that drive CF of the pancreas and facilitate development of new therapies to treat the disease.

Rapid urinary trypsinogen-2 test strip in the diagnosis of pancreatitis after endoscopic retrograde cholangiopancreatography

OBJECTIVES

The aim of this prospective study was to evaluate the diagnostic value of the rapid urinary trypsinogen-2 test strip in post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis.

METHODS

A total of 150 patients were tested with the urinary trypsinogen-2 test strip and serum levels of amylase and lipase before ERCP and 3 hours after ERCP. The diagnostic value of urinary trypsinogen-2 strip test compared with that of serum amylase and lipase was analyzed.

RESULTS

Post-ERCP pancreatitis was diagnosed in 13 (8.7%) of 150 patients. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of urinary trypsinogen-2 dipstick test at 3 hours after ERCP are 84.6%, 97.1%, 73.3%, 98.5%, and 96%, respectively. At the cutoff level of 3 times the upper reference limit, the negative predictive values of amylase and lipase were comparable to that urinary trypsinogen-2 strip test; however, their positive predictive values (42.9% and 36.4%, respectively) were markedly lower than that of urinary trypsinogen-2 test (73.3%).

CONCLUSIONS

The urinary trypsinogen-2 dipstick test is a useful test for early diagnosis of post-ERCP pancreatitis. A negative urinary dipstick test at 3 hours after the procedure rules out post-ERCP pancreatitis with a high probability and allows of early discharge plan.

Assessment of trypsinogen-2 levels as an early diagnostic for post-endoscopic retrograde cholangiopancreatography pancreatitis

OBJECTIVES

The objective of the present study was to assess the use of serum trypsinogen-2 (TRY-2) measurements in early diagnosis of pancreatitis after endoscopic retrograde cholangiopancreatography (ERCP).

METHODS

In this prospective study, investigation 1 involved collection of blood serum both before and at 2, 4, and 18 hours after ERCP, whereas investigation 2 involved collection before and 1, 2, 3, 4, 6, and 18 hours after ERCP. Total amylase, pancreatic amylase, and TRY-2 levels were measured from serum samples, and values from patients with pancreatitis after ERCP were compared to those from healthy control patients after ERCP.

RESULTS

In investigation 1, 8 of the 68 cases examined were diagnosed as post-ERCP pancreatitis. In the healthy group, total- and pancreatic-amylase levels peaked 4 hours after ERCP, and TRY-2 levels peaked at 2 hours after ERCP. In contrast, cases of post-ERCP pancreatitis demonstrated prolonged periods of high total-amylase, pancreatic-amylase, and TRY-2 levels. In investigation 2, none of the 23 cases was diagnosed as post-ERCP pancreatitis: Pancreatic amylase levels peaked 4 to 6 hours after ERCP and TRY-2 levels peaked 1 hour after ERCP.

CONCLUSION

These results suggest that TRY-2 is a more sensitive marker than amylase, and it can be useful in early diagnosis of post-ERCP pancreatitis.

Prevention of post-endoscopic retrograde cholangiopancreatography pancreatitis by epinephrine sprayed on the papilla

BACKGROUND AND AIM

Epinephrine sprayed on the papilla may reduce papillary edema and prevent acute pancreatitis after endoscopic retrograde cholangiopancreatography (ERCP). The aim of this study was to evaluate the effects of localized irrigation with epinephrine saline for prevention of post-ERCP pancreatitis (PEP).

METHODS

A total of 941 patients who were scheduled for ERCP were recruited into this study. We randomized the patients to have 20 mL of either 0.02% epinephrine or saline sprayed on the papilla after diagnostic ERCP to prevent post-ERCP pancreatitis. We recorded duct visualization, presence of pancreatic acinarization, number of injections into the pancreatic duct, total volume of contrast used, and procedure duration. The serum amylase levels were measured at 6, 24 and 48 h after ERCP. We counted the patients of PEPs and compared whether there was significant difference between the pancreatitis group and the no pancreatitis group.

RESULTS

A univariate analysis of the explanatory variables between the epinephrine and control groups, the pancreatitis and no pancreatitis groups revealed the treatment to be effective, but most of the groups were not statistically significant. PEPs occurred in 40 of the 941 patients (4.25%), the incidence of pancreatitis tended to be higher in the control group (31/480, 6.45%) than in the epinephrine group (9/461, 1.95%) (P = 0.0086).

CONCLUSIONS

Epinephrine sprayed on the papilla may be effective to prevent PEP. Female patients (aged ≥ 18 years and < 35 years) (7/40, 17.5%), common bile duct diameter < 10 mm (27/40, 67.5%), previous cholangitis (3/40, 7.5%), body mass index ≥ 24 (22/40, 55%), and/or serum triglycerides ≥ 5.65 mmol/L (6/40, 15%), might be risk factors for post-ERCP pancreatitis, but are not statistically significant in the study.

Pancreatic sphincterotomy versus needle knife precut in difficult biliary cannulation

BACKGROUND

In endoscopic retrograde cholangiopancreaticography (ERCP) difficult cannulation is an independent risk factor for complications.

METHODS

Altogether 6,209 ERCPs were performed in Helsinki University Central Hospital in the period 1996-2006. In 558 cases (9%) without a previous sphincterotomy, direct access into the biliary duct could not be achieved. In this group access was attempted by first performing a pancreatic sphincterotomy in 351 difficult cannulation cases (63%). A needle knife precut without a pancreatic sphincterotomy was performed in 178 cases (32%). All the necessary clinical and laboratory information was available for 262 of the 351 patients who had undergone a pancreatic sphincterotomy and for 157 of the 178 patients who had been subjected to needle knife precutting, and these data were further evaluated in this study.

RESULTS

The pancreatic sphincterotomy technique was successful in 255 cases (97.3%). Post-ERCP pancreatitis developed in 8.8% of the pancreatic sphincterotomy group. In 147 patients, biliary cannulation was successful following a pancreatic sphincterotomy, and the post-ERCP pancreatitis rate for those patients was 9.3%. In 108 patients, a needle knife papillotomy, in addition to a pancreatic sphincterotomy, was necessary and resulted in a post-ERCP pancreatitis rate of 8.2%. In the needle knife precut group only, post-ERCP pancreatitis developed in 5.1% of cases. Biliary cannulation succeeded less frequently following needle knife precutting than following the pancreatic sphincterotomy technique (71.3% versus 97.3%, p<0.001). There was no significant difference in the post-ERCP pancreatitis rate between the precut and pancreatic sphincterotomy techniques (p=0.16).

CONCLUSIONS

In difficult cannulation, a pancreatic sphincterotomy to achieve deep biliary duct cannulation can be performed with a high success rate (failure rate less than 3%). The corresponding success rate using the needle knife precut technique is 71%. In both methods the risk for post-ERCP pancreatitis is comparable to that of a standard biliary sphincterotomy.

Epinephrine sprayed on the papilla for prevention of post-ERCP pancreatitis

BACKGROUND

Epinephrine sprayed on the papilla may reduce papillary edema and thus prevent acute pancreatitis after endoscopic retrograde cholangiopancreatography (ERCP). The aim of this study was to determine the efficacy of this technique for prevention of post- ERCP pancreatitis.

METHODS

Patients scheduled for ERCP were recruited into this study. We randomized the patients to have 10 ml of either 0.02% epinephrine (epinephrine group) or saline (control group) sprayed on the papilla after diagnostic ERCP and prospectively analyzed the occurrence of post-ERCP pancreatitis between the groups. We recorded duct visualization, presence of pancreatic acinarization, number of injections into the pancreatic duct, total volume of contrast used, and procedure duration.

RESULTS

There was no significant difference between the groups with regard to visualization of the bile duct and/or the main and accessory pancreatic ducts, presence of pancreatic acinarization, number of injections into the pancreatic duct, total volume of contrast used, and procedure duration. Overall, post-ERCP pancreatitis occurred in 4 of the 370 patients (1.1%). The incidence of pancreatitis tended to be higher in the control group (4/185) than in the epinephrine group (0/185) (P = 0.1230).

CONCLUSIONS

Epinephrine sprayed on the papilla tended to prevent post-ERCP pancreatitis, although it was not statistically significant because of the low incidence of pancreatitis. Further studies on the efficacy of this technique in patients at high risk for pancreatitis, and on other volumes and/or concentrations of epinephrine, are warranted.

Acute pancreatitis

Acute pancreatitis is an inflammatory disease of the pancreas. Acute abdominal pain is the most common symptom, and increased concentrations of serum amylase and lipase confirm the diagnosis. Pancreatic injury is mild in 80% of patients, who recover without complications. The remaining patients have a severe disease with local and systemic complications. Gallstone migration into the common bile duct and alcohol abuse are the most frequent causes of pancreatitis in adults. About 15-25% of pancreatitis episodes are of unknown origin. Treatment of mild disease is supportive, but severe episodes need management by a multidisciplinary team including gastroenterologists, interventional radiologists, intensivists, and surgeons. Improved understanding of pathophysiology and better assessments of disease severity should ameliorate the management and outcome of this complex disease.

Use of the urinary trypsinogen-2 dip stick test in early diagnosis of pancreatitis after endoscopic retrograde cholangiopancreatography

BACKGROUND

This study aimed to prove that the urinary trypsinogen-2 dip stick test can be used for early diagnosis of pancreatitis after endoscopic retrograde cholangiopancreatography (ERCP).

METHODS

For this prospective, blinded, pilot study, urine samples were collected before ERCP, 1 h after ERCP, and 4 h after ERCP. The urine dipstick test was used to detect trypsinogen-2 on the basis of immunochromatography. The dipstick results were compared with those of current methods used to diagnose post-ERCP pancreatitis. Once the patient disposition was finalized, pancreatic enzymes, clinical findings, and final diagnosis were obtained from the chart and compared with the urine trypsinogen-2 test findings. The sensitivity, specificity, and positive and negative predictive values were calculated.

RESULTS

The urine trypsinogen dip stick test was performed for 30 patients (15 men and 15 women). Post-ERCP pancreatitis was diagnosed in 5 of 29 patients by clinician assessment, serum pancreatic enzyme levels, or both. The amylase and lipase levels for post-ERCP patients with and without pancreatitis were 650 +/- 145 vs 134 +/- 26 (p = 0.023) and 1,658 +/- 594 vs 84 +/- 17 (p = 0.057), respectively. This statement proves that patients who developed post ERCP pancreatitis had significant elevation of amylase and lipase compared to patients who did not have pancreatitis. For the dip stick test, 6 of 28 patients had positive results in 1 h and 6 of 29 patients had positive results in 4 h. The sensitivity of the 1-h test was 1.0, and the specificity was 0.91. The positive predictive value (PPV) was 0.66, and the negative predictive value (NPV) was 1.0. The sensitivity of the 4-h test was 1.0, and the specificity was 0.96. The PPV was 0.8, and NPV value was 1.0.

CONCLUSION

The urinary trypsinogen-2 dip stick test is useful for early diagnosis of post-ERCP pancreatitis and allows the testing physicians to begin management early in its course.

Biochemistry and clinical role of trypsinogens and pancreatic secretory trypsin inhibitor

Trypsinogens and PSTI/TATI/SPINK1 are expressed, usually together, at high levels by the pancreas but also by many other normal and malignant tissues. The present review describes studies on the expression and putative functions of trypsinogens and PSTI/TATI/SPINK1 in the human body. The clinical aspects are discussed, including the correlations between expression of trypsinogens and PSTI/TATI/SPINK1 in tissues, serum, and urine of patients with pancreatitis or cancer and clinicopathological characteristics, i.e., the roles of trypsinogens and PSTI/TATI/SPINK1 in spontaneous and hereditary pancreatitis, tumor progression, and prognosis.

Biochemical markers of acute pancreatitis

Serum amylase remains the most commonly used biochemical marker for the diagnosis of acute pancreatitis, but its sensitivity can be reduced by late presentation, hypertriglyceridaemia, and chronic alcoholism. Urinary trypsinogen-2 is convenient, of comparable diagnostic accuracy, and provides greater (99%) negative predictive value. Early prediction of the severity of acute pancreatitis can be made by well validated scoring systems at 48 hours, but the novel serum markers procalcitonin and interleukin 6 allow earlier prediction (12 to 24 hours after admission). Serum alanine transaminase >150 IU/l and jaundice suggest a gallstone aetiology, requiring endoscopic retrograde cholangiopancreatography. For obscure aetiologies, serum calcium and triglycerides should be measured. Genetic polymorphisms may play an important role in "idiopathic" acute recurrent pancreatitis.

Serum amylase, pancreatic stents, and pancreatitis after sphincter of Oddi manometry

BACKGROUND

Serum amylase levels 2 hours after ERCP predict postprocedure pancreatitis. The value of serum amylase measurements after sphincter of Oddi manometry (SOM) and the effect of pancreatic-duct stent placement on serum amylase are unknown.

METHODS

Records were reviewed for 88 SOM patients who had serum amylase measured 2 hours after the procedure. Post-SOM pancreatitis was defined as pain with a >3-fold elevation of serum amylase on the morning after SOM. "Possible pancreatitis" was defined as pain with a <3-fold elevation of serum amylase on the morning after SOM.

RESULTS

Post-SOM pancreatitis and possible pancreatitis each occurred in 13% of the study cohort. Post-SOM pancreatitis was associated with the absence of a pancreatic stent and occurred in 0% of patients without a stent who had normal 2-hour serum amylase vs. 67% with elevated 2-hour serum amylase (p < 0.01). Among patients who received a stent, pancreatitis occurred in 6%, regardless of whether the 2-hour serum amylase was elevated. Possible pancreatitis occurred mainly in patients who received stents, and it also was associated with elevation of the 2-hour serum amylase.

CONCLUSIONS

Elevation of the serum amylase level 2 hours after SOM predicts post-SOM pancreatitis but only in patients who do not receive a pancreatic stent. Among patients who received a stent, elevated 2-hour serum amylase levels predict subsequent findings that may be caused by attenuated pancreatitis.

Clinical laboratory assessment of acute pancreatitis

BACKGROUND

Several biochemical markers in blood and urine have been investigated to establish their clinical application in patients with acute pancreatitis (AP). The relevant studies are reviewed and critically appraised.

METHODS

Medline and the World Wide Web were searched and the relevant literature was classified under the following categories: (1) diagnosis of AP and (2) prediction of: a) disease severity, b) pancreatic necrosis and its secondary infection, c) organ failure and death, and d) disease etiology.

RESULTS AND CONCLUSIONS

Serum lipase is a more reliable diagnostic marker of AP than serum amylase. Urinary strip tests for trypsinogen activation peptide (TAP) and trypsinogen-2 provide a reliable early diagnosis of AP. Useful predictors of severity may include serum procalcitonin and urinary TAP and trypsinogen-2 on admission, serum interleukins-6 and -8 and polymorphonuclear elastase at 24 h, and serum C-reactive protein (CRP) at 48 h. Other markers such as amyloid A and carboxypeptidase B activation peptide (CAPAP) need further investigation. Biochemical prediction of pancreatic necrosis requires 72 h to reach reliability and is impractical. However, the daily monitoring of serum procalcitonin provides a non-invasive detection of infected necrosis; the promising role of phospholipase A(2) in this regard requires further investigation. Early transient hypertransaminasemia reliably predicts biliary etiology, while serum carbohydrate-deficient transferrin and trypsin may predict an alcoholic etiology.

Early sequential changes in serum markers of acute pancreatitis induced by endoscopic retrograde cholangiopancreatography

BACKGROUND/AIMS

Trypsinogen activation is thought to play a crucial role in the pathogenesis of acute pancreatitis (AP). Our aim was to characterize the very early sequential changes of trypsinogen-1, trypsinogen-2, the trypsin-2-alpha1-antitrypsin complex (T2-AAT), and pancreatic secretory trypsin inhibitor (PSTI) in serum from patients with pancreatitis induced by endoscopic retrograde cholangiopancreatography (ERCP), a model for studying the early phase of the disease in humans.

PATIENTS AND METHODS

The study population consisted of 659 consecutive patients with 897 ERCP procedures. Blood samples were obtained before and at different time points after the procedure. The serum concentrations of trypsinogen-1 and trypsinogen-2, PSTI and T2-AAT were determined by time-resolved immunofluorometric assays.

RESULTS

ERCP-induced pancreatitis developed after 50 of the 897 ERCP procedures (5.6%). Sixty-one randomly selected ERCP patients without post-ERCP pancreatitis served as controls. Trypsinogen-1 and trypsinogen-2 showed an equally steep increase during the two first hours after ERCP in patients developing AP, but trypsinogen-1 decreased more rapidly than trypsinogen-2, which remained elevated during the 5-day study period. Serum PSTI also increased rapidly whereas T2-AAT increased more slowly peaking at 24 h. In patients developing post-ERCP pancreatitis the median concentration of trypsinogen-1 was markedly higher than in the controls already before the ERCP procedure. In the control group the concentrations of trypsinogen-1, trypsinogen-2, PSTI and T2-AAT did not change significantly.

CONCLUSIONS

The rapid increase of trypsinogen-1 and trypsinogen-2 and PSTI in the early phase of AP suggests that release of pancreatic enzymes is the initial event while the delayed increase of T2-AAT may reflect that the capacity of the intrapancreatic PSTI-based inhibitory mechanism has been exhausted.

Serum trypsinogen activation peptide in the assessment of the diagnosis and severity of acute pancreatic damage: a pilot study using a new determination technique

OBJECTIVES

To evaluate the clinical value of a new direct and competitive immunoassay for trypsinogen activation peptide (TAP) determination in acute pancreatitis (AP).

METHODS

The subjects were 34 patients with AP (22 mild, 12 severe), 12 patients with nonpancreatic acute abdominal pain (AA), 11 healthy subjects (HS), and 16 consecutive patients who underwent therapeutic ERCP (ERCP). Serum TAP, amylase, and lipase levels were determined in AP, AA, and HS at their initial observation; the AP patients were also studied for 6 consecutive days after admission. In the ERCP patients, serum TAP, amylase, and lipase levels, as well as urine TAP and amylase levels, were determined before and 6 hours after endoscopy.

RESULTS

Serum TAP levels on admission were 0.35 +/- 1.60 OD (mean +/- SD) in AP patients and 0.005 +/- 0.001 OD in AA patients, while HS patients had no detectable serum TAP levels. ERCP patients had no detectable serum TAP levels before and 6 hours after the ERCP, whereas urine TAP concentrations were 1.72 +/- 3.43 OD and 0.75 +/- 1.49 OD before and 6 hours after the execution of the endoscopy, respectively (P = 0.249). The sensitivities and specificities of serum TAP, amylase, and lipase levels in discriminating between AP and AA were 23.5% and 91.7%, 94.1% and 100%, and 97.1% and 100%, respectively, while those used in the assessment of the severity of AP were 29.9% and 73.5%, 38.8% and 81.2%, and 28.4% and 83.6%, respectively.

CONCLUSION

TAP is of limited value in assessing the diagnosis and the severity of acute pancreatic damage.

Severe acute pancreatitis is related to increased early urinary levels of the activation Peptide of pancreatic phospholipase A(2)

BACKGROUND/AIM

In acute pancreatitis, it is believed that generalized activation of pancreatic zymogens leads to autodigestion of the pancreas and if excessive to systemic organ injury. Under physiological circumstances, secretory phospholipase A(2) type I (sPLA(2)-I) is activated by trypsinogen, but the extent of this activation in acute pancreatitis is unclear. The aim of this study was to assess time course and level of activation of sPLA(2)-I and trypsinogen in acute pancreatitis, relative to severity.

METHODS

246 patients were enrolled into a prospective European multicenter study. 137 patients had mild and 35 had severe acute pancreatitis, and there were 74 control patients. Urinary samples were taken on admission and at 6-hour intervals for 48 h, then every 12 h up to 72 h, and finally daily for at least 5 days for measurement of the activation peptide of sPLA(2)-I (pro-phosphatase A(2); PROP) and trypsinogen activation peptide.

RESULTS

The median maximum PROP values were significantly elevated 48 h after symptom onset in patients with severe acute pancreatitis [1.52 (95% CI 0.8-2.9) nmol/l] as compared with patients with mild acute pancreatitis [0.72 (0.55-1) nmol/l, p = 0.002] and controls [0.49 (0.22-1.2) nmol/l, p = 0.001], but not before or after this time point. The best cutoff point for urinary PROP to predict overall severity was >1 nmol/l < or =48 h after symptom onset (negative predictive value = 88%), but the PROP levels failed to predict the development of multi-organ dysfunction.

CONCLUSIONS

Activation of sPLA(2)-I is associated with the early pathogenesis of acute pancreatitis, but not in the development of distant organ damage. This observation raises questions as to the theory of generalized zymogen activation being a principle mechanism involved in the pathogenesis of distant organ damage in acute pancreatitis.

Do normal leucocyte count and C-reactive protein on admission to hospital exclude a life-threatening attack of acute pancreatitis?

BACKGROUND AND AIMS

The early severity assessment of an attack of acute pancreatitis is clinically of utmost importance. The aim of the present work was to study the role of leucocyte count and C-reactive protein (CRP) measurements on admission to hospital in assessing the severity of an attack of acute pancreatitis. In particular, patients with a life-threatening attack of acute pancreatitis but a normal leucocyte count and CRP level were sought.

MATERIAL AND METHODS

A total of 1050 attacks of acute pancreatitis were treated at Turku University Central Hospital during the years 1995-1999. Leucocyte count and C-reactive protein (CRP) value were determined on admission to hospital. There were 58 life-threatening attacks of acute pancreatitis (group A). Fifty-eight consecutive mild attacks served as controls (group B). The number of patients with both values normal, only leucocyte count raised, only CRP level raised and both values raised were calculated in the groups A and B.

RESULTS

Both leucocyte count and CRP level were significantly (P < 0.001 in both comparisons) higher on admission to hospital in patients with a life-threatening disease (group A) than in those with a mild disease (group B). Group A contained no patients with both values in the normal range. In group B, one fifth of the patients had both values normal.

CONCLUSION

It is very unlikely that acute pancreatitis proves to be a life-threatening one when both the leucocyte count and CRP are normal on admission to hospital. In the present 1050 acute pancreatitis there were no patients with life-threatening disease but normal laboratory values on admission.

Pancreatitis

In the past decade, our understanding of the genetic basis, pathogenesis, and natural history of pancreatitis has grown strikingly. In severe acute pancreatitis, intensive medical support and non-surgical intervention for complications keeps patients alive; surgical drainage (necrosectomy) is reserved for patients with infected necrosis for whom supportive measures have failed. Enteral feeding has largely replaced the parenteral route; controversy remains with respect to use of prophylactic antibiotics. Although gene therapy for chronic pancreatitis is years away, our understanding of the roles of gene mutations in hereditary and sporadic pancreatitis offers tantalising clues about the disorder's pathogenesis. The division between acute and chronic pancreatitis has always been blurred: now, genetics of the disorder suggest a continuous range of disease rather than two separate entities. With recognition of pancreatic intraepithelial neoplasia, we see that chronic pancreatitis is a premalignant disorder in some patients. Magnetic resonance cholangiopancreatography and endoscopic ultrasound are destined to replace endoscopic retrograde cholangiopancreatography for many diagnostic indications in pancreatic disease.

The true value of serum elastase-1 in endoscopic retrograde cholangiopancreatography (ERCP)

BACKGROUND: The routine use of serum elastase-1 in patients, pre- and post-endoscopic retrograde cholangiopancreatography (ERCP), has been strongly supported but not sufficiently correlated with diagnosis, patient outcome/prognosis, or routine markers such as serum amylase. The value of serum elastase-1 post-ERCP, as far as clinical diagnosis and prognosis is concerned, was tested and compared with serum amylase in terms of sensitivity, specificity, positive prognostic value (PPV), and negative prognostic value (NPV). METHODS: In a prospective study of 38 consecutive patients undergoing ERCP, we assessed the following biochemical parameters 24 h before ERCP and 2 and 18 h after ERCP: alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyltransferase (gamma-GT), alkaline phosphatase (ALP), amylase (AMS), lactate dehydrogenase (LDH), and pancreatic elastase-1. RESULTS: Statistically significant changes were found between pre-ERCP and 18-h post-ERCP in elastase-1 (P=0.009), amylase (P=0.016), gamma-GT (P=0.04), and ALP (P=0.04). Changes between 2-h and 18-h post-ERCP in all parameters tested were not statistically significant. No statistical significance was found between any biochemical parameter and specific ERCP diagnosis. CONCLUSIONS: This study showed that 2-h post-ERCP serum elastase-1 was 100% specific for post-ERCP pancreatitis or other underlying severe pathology while, at the same time, amylase was only 50% specific. The specificity of serum elastase-1 still remained high (87.5%) 18-h post-ERCP, while amylase only had a specificity of 25% at that time. In contrast, amylase had a sensitivity of 83.3 and 90% in the 2-h and 18-h post-ERCP serum samples, while elastase-1 only had a sensitivity of 56.7 and 73.3%, respectively.

Endoscopic retrograde cholangiopancreatography should no longer be used as a diagnostic test: the case against

Endoscopic retrograde cholangiopancreatography has been used successfully in diagnosis of pancreatico-biliary diseases. Over the past decade, there have been tremendous developments in radiological technologies which have led to the emergence of new and less invasive modalities like endoscopic ultrasound and spiral computed tomography and magnetic resonance cholangiopancreatography. Understandably, the usefulness of diagnostic endoscopic retrograde cholangiopancreatography is being questioned primarily because of its potential attendant complications. Therefore, this controversial question needs to be debated in the gastroenterology community. In this article, we compare the efficacy of newer diagnostic tools with existing "gold standard" modality--endoscopic retrograde cholangiopancreatography, and put forward our arguments in favour of a continuing role for endoscopic retrograde cholangiopancreatography as a diagnostic tool in certain circumstances.

Enzyme leakage, trypsinogen activation, and inflammatory response in endoscopic retrograde cholangiopancreatography-induced pancreatitis

INTRODUCTION

Endoscopic retrograde cholangiopancreatography (ERCP)-induced pancreatitis (EIP) provides an opportunity to study different pathophysiologic events early in the course of acute pancreatitis.

AIMS

To investigate whether the leakage of pancreatic proenzymes (anionic trypsinogen), pancreatic protease activation (carboxypeptidase B activation peptide), cytokine response (interleukin [IL]-1 receptor antagonist, IL-6, and soluble tumor necrosis factor receptor-I) and neutrophil activation (neutrophil gelatinase-associated lipocalin and polymorphonuclear elastase) differ between patients with and without EIP. A second aim was to clarify the temporal relation between these different events.

METHODOLOGY

Ninety-nine nonconsecutive patients undergoing ERCP were investigated in the study.

RESULTS

Fourteen of 99 patients undergoing ERCP developed mild EIP. Six hours after the investigation the concentration of anionic trypsinogen was significantly higher in patients with EIP than in patients without EIP. The day after ERCP, higher concentrations of anionic trypsinogen, carboxypeptidase B activation peptide, IL-6, and polymorphonuclear elastase were recorded in the EIP group. No significant differences in IL-1 receptor antagonist, soluble tumor necrosis factor receptor-I or neutrophil gelatinase-associated lipocalin were found between the groups in this study.

CONCLUSION

Mild EIP was accompanied by early leakage of proenzymes and later activation of trypsinogen/proteases. A significant cytokine response and neutrophil activation were recorded the day after ERCP, but further studies are needed to determine the temporal relation between these different pathophysiologic events.

Predicting and preventing post-ERCP pancreatitis

Pancreatitis is rightly the most feared complication of endoscopic retrograde cholangiopancreatography (ERCP). Ten percent to 15% of cases of post-ERCP pancreatitis (PEP) are severe by clinical and radiologic criteria. Such cases carry significant morbidity and mortality and are responsible for the vast majority of ERCP-related deaths. The prediction and prevention of PEP have been of great interest to endoscopists since the introduction of ERCP 30 years ago. Prediction and diagnosis of PEP have become more accurate with the widespread availability of serum amylase estimation. A variety of cytokines (eg, interleukin -1, IL-6, and IL-8) and acute phase reactants (eg, C-reactive protein) are also elevated in the serum in acute pancreatitis, and these form the basis of evolving tests for PEP. Urine testing (for amylase) in acute pancreatitis is obsolete, but it may soon undergo a revival in the form of a rapid (3-minute) dipstick test for trypsinogen-2, a sensitive and specific test for this disease. The prevention of PEP takes multiple forms. The following steps are recommended for clinicians: 1) avoid ERCP when other, less invasive or noninvasive imaging tests can do the job (eg, CT or magnetic resonance imaging); 2) avoid high-risk (of PEP) procedures, such as needle-knife papillotomy, balloon dilation of the biliary sphincter, and pancreatic sphincterotomy, and take steps to reduce risk when these procedures are unavoidable; 3) ensure that those who perform ERCP have adequate training and experience; and 4) consider pharmacologic intervention. Despite a depressing catalog of drug interventions that have failed over the years (eg, antihistamines, anticholinergics, and corticosteroids), three agents have recently shown promise: somatostatin; its octapeptide analogue, octreotide; and gabexate mesylate, a protease inhibitor.

Acute pancreatitis in Soweto, South Africa: relationship between trypsinogen load, trypsinogen activation, and fibrinolysis

OBJECTIVE

It is not known why acute pancreatitis in Soweto, South Africa, pursues an aggressive course. We sought clues from circulating trypsinogen load at admission as marker of initial acinar injury, trypsinogen activation using the carboxypeptidase B activation peptide as surrogate, proteinase inhibitors, the coagulation-fibrinolysis axis, indicators of inflammation, oxidative stress markers, and antioxidant status. This article reports on the first four aspects.

METHODS

The study involved 24 consecutive patients with a first attack. All of them were admitted within 24 h, and 22 were alcoholic. Urine was analyzed for anionic trypsinogen and the carboxypeptidase B activation peptide. Serum was tested for anionic and cationic trypsinogen, alpha1 proteinase inhibitor and alpha2 macroglobulin. Plasma from a subset was assayed for soluble fibrin, cross-linked fibrin degradation products (surrogates for thrombin and plasmin activity, respectively), and tissue-type plasminogen activator and inhibitor.

RESULTS

Soweto controls had higher serum anionic trypsinogen (p = 0.004) and plasminogen activator:inhibitor ratio (p = 0.047) than U.K. controls. The outcome of acute pancreatitis was mild in 17 but severe in seven with three deaths, two on day 2. In mild pancreatitis, intense plasmin activity (p < 0.001) accompanied the surge in trypsinogen, especially anionic (p < 0.001), but without increased thrombin activity and in five patients without trypsinogen activation. In severe pancreatitis, further significant increments in plasmin activity and trypsinogens were accompanied by increased thrombin activity (p = 0.013) and trypsinogen activation (p = 0.046). There was no correlation between surrogates of plasmin and thrombin activity, or between either and the carboxypeptidase B activation peptide, which showed a curvilinear relationship to total serum trypsinogen.

CONCLUSIONS

The aggressive nature of alcoholic acute pancreatitis in Soweto seems to reflect early profound fibrinolysis, which precedes coagulation and is initially independent of trypsin. Subclinical acinar-cell injury and a profibrinolytic diathesis in outwardly healthy Sowetans may predispose to this problem.

Review of feline pancreatitis part two: clinical signs, diagnosis and treatment

In the past decade pancreatitis has become recognised as a significant disease in the cat. Chronic, mild pancreatitis is often associated with more commonly diagnosed diseases such as inflammatory bowel disease or cholangitis/cholangiohepatitis. Furthermore, acute pancreatitis with similar complications to those seen in dogs is now diagnosed more frequently in cats. Unfortunately, the clinical signs and clinicopathological findings in cats with pancreatitis are often non-specific and vague. The lack of specific signs often results in a diagnosis being made only when the veterinary surgeon has a strong index of suspicion for pancreatitis and vigorously pursues that diagnosis. Pancreatitis is an important disease in cats, has been implicated as a potential cause of diabetes mellitus, and when present complicates the treatment of diabetes and other intra-abdominal diseases in cats.

Diagnostic and therapeutic ERCP: a large single centre's experience

BACKGROUND

Most large published series on endoscopic retrograde cholangiopancreatography (ERCP) are multicentre-based and consequently reflect varying experience.

AIMS

To assess morbidity and mortality rates of ERCP in a single tertiary referral centre.

METHODS

A series of 1,758 consecutive ERCPs performed in 1,148 patients between 1991 and 1994 were reviewed to evaluate indications, findings, procedures, success, complication and mortality rates.

RESULTS

There were 1,108 (63%) successful initial ERCPs, 11% failed cannulation attempts and 26% follow-up ERCPs. The desired duct was successfully cannulated in 96.5% of cases. Initial cannulation failure rate was 8.8%. Twenty-seven per cent had normal ERCPs, 30% had choledocholithiasis and 22% had strictures. Fifty-five per cent had therapeutic ERCPs. Major complications occurred in 3.5% with four ERCP-related deaths (0.35%). Therapeutic ERCP had a higher incidence of major complications compared to diagnostic ERCP: 4.6% vs 2.1%, (p=0.02); and mortality rate was 0.5% vs 0.2%, (p=0.4). Significant haemorrhage secondary to biliary sphincterotomy, pre-cut papillotomy and snare papillectomy accounted for most of the difference (1.6%).

CONCLUSIONS

The majority of ERCPs were performed in elderly patients, over half of whom required therapeutic ERCP. Therapeutic ERCP carried significantly higher complication rate compared with diagnostic ERCP. Unsuccessful cannulation and follow-up ERCP accounted for 11% and 26% of ERCP workload, respectively.

The Ratio of Trypsin-2-α1-Antitrypsin to Trypsinogen-1 Discriminates Biliary and Alcohol-induced Acute Pancreatitis

Background: Rapid determination of the etiology of acute pancreatitis (AP) enables institution of appropriate treatment. We evaluated the ability of trypsinogen-1, trypsinogen-2, trypsin-1-α1-antitrypsin (AAT), and trypsin-2-AAT in serum to identify the etiology of AP.

Methods: The study consisted of 67 consecutive patients with AP admitted to Helsinki University Central Hospital. Forty-two had alcohol-induced AP, 16 had biliary AP, and 9 had unexplained etiology. Serum samples were drawn within 12 h after admission. Trypsinogen-1, trypsinogen-2, trypsin-1-AAT, and trypsin-2-AAT were determined by time-resolved immunofluorometric assays. Logistic regression was used to estimate the ability of the serum analytes to discriminate between alcohol-induced and biliary AP. The validity of the tests was evaluated by ROC curve analysis.

Results: Patients with alcohol-induced AP had higher median values of trypsin-1-AAT (P = 0.065), trypsinogen-2 (P = 0.034), and trypsin-2-AAT (P &lt;0.001) than those with biliary AP, who had higher values of amylase (P = 0.002), lipase (P = 0.012), and alanine aminotransferase (P = 0.036). The ratios of trypsin-2-AAT to trypsinogen-1, lipase, or amylase efficiently discriminated between biliary and alcohol-induced AP (areas under ROC curves, 0.92–0.96).

Conclusions: Trypsinogen-2 and trypsin-2-AAT are markedly increased in AP of all etiologies, whereas trypsinogen-1 is increased preferentially in biliary AP. The trypsin-2-AAT/trypsinogen-1 ratio is a promising new marker for discrimination between biliary and alcohol-induced AP.

Time course profile of serum trypsinogen-2 and trypsin-2-alpha1-antitrypsin in patients with acute pancreatitis

BACKGROUND

Trypsinogen-2 and the trypsin-2-alpha1-antitrypsin complex are recently introduced new laboratory markers for acute pancreatitis. They show high sensitivity and specificity for acute pancreatitis on admission, but little is known on their time course profiles.

METHODS

The serum concentrations of trypsinogen-2 and trypsin-2-alpha1-antitrypsin were monitored in 92 patients with verified acute pancreatitis. The follow-up period was 42 days in patients with severe acute pancreatitis (N = 73) and 9 days in mild disease (N = 19).

RESULTS

On admission the mean serum concentration of trypsinogen-2 was 2880 microg/l in severe and 920 microg/l in mild acute pancreatitis. These values were 32- and 10-fold the upper reference limit, respectively. Trypsin-2-alpha1-antitrypsin concentrations were 1250 microg/l (100-fold the upper reference limit) and 635 microg/l (52-fold), respectively. The differences were statistically significant (P = 0.026-0.001). The concentrations of trypsinogen-2 and trypsin-2-alpha1-antitrypsin decreased gradually during the follow-up period, but they remained elevated for the entire study period in patients with severe and mild disease.

CONCLUSIONS

The time course profile of trypsinogen-2 and trypsin-2-alpha1-antitrypsin is favorable for diagnosing acute pancreatitis. The elevation starts within hours after the onset of the disease and it is very steep. Both markers remain elevated longer than amylase and the magnitude of the elevation correlates with the severity of the disease. This is further evidence to support the use of trypsinogen-2 and trypsin-2-alpha1-antitrypsin for the evaluation of patients suspected of having acute pancreatitis.

Proteases in the evaluation of pancreatic function and pancreatic disease

This paper reviews the role of pancreatic proteases (focusing upon trypsin, chymotrypsin and elastase) in the diagnosis and management of chronic pancreatic insufficiency (CPI), emphasizing advances over the last 5 years. Some important novel aspects of these enzymes in acute pancreatitis are also described, including their role in diagnosis and their interaction with cholecystokinin in the pathogenesis of the disease. The recent interest in these enzymes as agents promoting the spread of cancer in animals and human subjects is also described. A hierarchical approach has been taken to explore the advantages and limitations of tests in different source materials: serum, feces, duodenal aspirate, and non-invasive pancreatic function tests. The practical usefulness of fecal elastase-1 and of fecal chymotrypsin concentrations in diagnosis and management of CPI, respectively, is one of the major lessons to be learned from analysis of the recent literature, and forms the principal message of this review.

Interstitial trypsinogen release and its relevance to the transformation of mild into necrotizing pancreatitis in rats

BACKGROUND & AIMS

Intracellular activation of trypsinogen is currently believed to initiate pancreatitis. Factors responsible for the progression of mild to necrotizing pancreatitis are poorly understood. This study evaluated the significance of interstitial protease release and activation in this process.

METHODS

In rats with cerulein-induced pancreatitis, concentrations of trypsinogen and its activation peptide TAP were measured in lymph and blood, and pancreatic injury was determined. Activation of extracellular trypsinogen was induced by intravenous infusion of enterokinase, which does not enter the acinar cell. Gabexate mesilate (acinar cell permeable) or soybean trypsin inhibitor (acinar cell nonpermeable) was administered to distinguish the effects of intracellular or extracellular protease activation.

RESULTS

In cerulein pancreatitis, trypsinogen levels increased prominently and were highest in lymph and portal vein blood, whereas TAP increments were modest. Combined cerulein/enterokinase infusions resulted in marked TAP increases in lymph and blood and in severe necrohemorrhagic pancreatitis. Gabexate mesilate as well as soybean trypsin inhibitor significantly decreased TAP levels in both lymph and blood and reduced pancreatic injury, with no significant differences between groups.

CONCLUSIONS

In secretagogue-induced pancreatitis, large amounts of trypsinogen are present in the interstitium and drain via the portal and lymphatic circulation. Activation of this extracellular trypsinogen induces hemorrhagic necrosis in a setting of mild edematous pancreatitis. This phenomenon may be the central event in the progression to fulminant necrotizing pancreatitis.

Membrane-protease interactions. III: A consideration of the difference in binding potential of pancreatic proteases to erythrocytes and erythrocyte ghosts

Trypsin and chymotrypsin readily bind to human erythrocyte ghosts and to resealed right-side-out ghosts, but not to intact erythrocytes, as followed with [3H]trypsin and [3H]chymotrypsin and with cold proteases in a caseinolytic assay. The proteases freely reacted with casein in the presence of intact cells. Trypsin activated trypsinogen over an 8-hr time course at a faster rate in the presence of erythrocytes than in the absence thereof, after a slight initial delay. Trypsinogen did not bind to intact erythrocytes, thereby behaving comparably to trypsin. These results suggest that different microenvironments exist about the erythrocyte ghosts and the intact erythrocytes, thereby permitting the proteases to bind to the former but not to the latter. Hence, in the absence of considerable ghosts in circulating blood, which may mask the binding site of the proteases, the proteases may be more readily accessible for interaction with circulating serpins, leading to inactivation of the proteases and protection from their degradative potential. The presence of the serpins in circulating blood may assist in the control of the degradative power of the pancreatic proteases in pancreatitis and may negatively modulate such processes as thrombosis, activation of the complement system, and vascular remodeling.

Advances in the laboratory diagnostics of acute pancreatitis

Acute pancreatitis is a rather common abdominal disorder. In most patients the disease is mild, but about 20% of cases develop a severe necrotizing form of the disease with complications. In an emergency setting, the diagnosis of acute pancreatitis remains problematic and several patients with severe disease are diagnosed only at autopsy. Measurements of amylase or lipase are the principal laboratory methods for diagnosing acute pancreatitis. However, their sensitivity and specificity are generally considered unsatisfactory. Recent advances in the knowledge of the pathogenesis of acute pancreatitis and advances in laboratory technology have revealed new diagnostic possibilities. Especially assays based on trypsin pathophysiology have brought new alternatives for diagnostics and severity grading of the disease. Additionally, development of phospholipase A2 determinations and discovery of a new pancreatic protein, pancreatitis-associated protein, are very interesting. This article summarizes the value of new methods in the laboratory diagnostics of acute pancreatitis.