Reliable screening for acute pancreatitis with rapid urine trypsinogen-2 test strip

Utility of point-of-care urine trypsinogen dipstick test for diagnosing acute pancreatitis in an emergency unit

Background: A point-of-care diagnostic test for acute pancreatitis could help in early triage and management of this condition. Materials & methods: Urine trypsinogen dipstick test (UTDT) was performed in consecutive cases suspected to have acute pancreatitis and diagnostic accuracy calculated. Results: Of 187 patients, 90 were have acute pancreatitis and UTDT was positive in 61 (67.7%). In the 97 non pancreatitis cases, UTDT was positive in nine (9.3%). The sensitivity and specificity of UTDT for acute pancreatitis was 67.8% and 90.7%, respectively. In patients presenting within 3 days of abdominal pain, sensitivity and specificity were 72.7% and 91.8%, respectively. Discussion: While offering the possibility of a point of care diagnosis, the low sensitivity of UTDT could be a concern with its routine use.

Repeated Negative Urine Trypsinogen-2 Dipstick Test Rules Out Diagnosis of Post-ERCP Pancreatitis

BACKGROUND

A dipstick test for urine trypsinogen-2 has been used in the diagnosis of acute pancreatitis, but there are only a few studies exploring the effectiveness of this test for early diagnose of post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP).

GOALS

The authors explore if the rapid point-of-care urine trypsinogen-2 dipstick test can replace assay of amylase in diagnosing PEP.

STUDY

For this prospective study, from Helsinki University Hospital 400 ERCP patients were enrolled in whom the authors analyzed plasma amylase or pancreas-specific amylase, bilirubin, and urine trypsinogen-2, and urine trypsinogen-2 with dipstick before, 4 and 24 hours after ERCP.

RESULTS

PEP developed in 15 (3.8%) patients. Urine trypsinogen-2 concentrations were significantly higher in PEP than in non-PEP patients 24 hours after ERCP (P=0.001, Mann-Whitney U test) but not 4 hours after ERCP (P=0.094). When combined with abdominal pain symptoms at 4 hours the dipstick test had a sensitivity of 60%, a specificity of 99%, a positive predictive value of 64%, and a negative predictive value 98%. At 24 hours, sensitivity was 100%, specificity 98%, positive predictive value 71%, and negative predictive value 100%.

CONCLUSIONS

A positive dipstick seems to identify PEP cases and a negative test excludes PEP with high accuracy.

Modification of a nitrocellulose membrane with cellulose nanofibers for enhanced sensitivity of lateral flow assays: application to the determination of Staphylococcus aureus

Lateral flow assays, as a low-cost, simple, portable and disposable product of vitro diagnostic, are being widely used for point-of-care testing. However, the poor sensitivity of LFAs is the main challenge for commercialization. In order to enhance the sensitivity of LFAs, cellulose nanofibers (CNFs) have been integrated into LFAs to enhance the sensitivity of protein LFAs. A simple method is also presented to modify the properties of paper substrate by incorporating CNFs into a nitrocellulose membrane to enhance the sensitivity of nucleic acid LFAs. This method changes the pore size, porosity, surface groups and surface area of paper substrate and then increases the adsorption ability of biomolecules on paper substrate. The results indicate that the sensitivity of nucleic acid LFAs in Staphylococcus aureus testing achieves a 20-fold enhancement. Hence, we anticipate that this simple method has the potential for other paper-based devices to improve the performance. Graphical abstractA simple method is used to modify the properties of paper substrate by incorporating cellulose nanofibers (CNFs) into nitrocellulose (NC) membrane to enhance the sensitivity of nucleic acid LFAs.

Usefulness of urinary trypsinogen-2 and trypsinogen activation peptide in acute pancreatitis: A multicenter study in Japan

BACKGROUND

Rapid urinary trypsinogen-2 dipstick test and levels of urinary trypsinogen-2 and trypsinogen activation peptide (TAP) concentration have been reported as prognostic markers for the diagnosis of acute pancreatitis.

AIM

To reconfirm the validity of all these markers in the diagnosis of acute pancreatitis by undertaking a multi-center study in Japan.

METHODS

Patients with acute abdominal pain were recruited from 17 medical institutions in Japan from April 2009 to December 2012. Urinary and serum samples were collected twice, at enrollment and on the following day for measuring target markers. The diagnosis and severity assessment of acute pancreatitis were assessed based on prognostic factors and computed tomography (CT) Grade of the Japanese Ministry of Health, Labour, and Welfare criteria.

RESULTS

A total of 94 patients were enrolled during the study period. The trypsinogen-2 dipstick test was positive in 57 of 78 patients with acute pancreatitis (sensitivity, 73.1%) and in 6 of 16 patients with abdominal pain but without any evidence of acute pancreatitis (specificity, 62.5%). The area under the curve (AUC) score of urinary trypsinogen-2 according to prognostic factors was 0.704, which was highest in all parameter. The AUC scores of urinary trypsinogen-2 and TAP according to CT Grade were 0.701 and 0.692, respectively, which shows higher than other pancreatic enzymes. The levels of urinary trypsinogen-2 and TAP were significantly higher in patients with extended extra-pancreatic inflammation as evaluated by CT Grade.

CONCLUSION

We reconfirmed urinary trypsinogen-2 dipstick test is useful as a marker for the diagnosis of acute pancreatitis. Urinary trypsinogen-2 and TAP may be considered as useful markers to determine extra-pancreatic inflammation in acute pancreatitis.

Paper-based assays for urine analysis

A transformation of the healthcare industry is necessary and imminent: hospital-centered, reactive care will soon give way to proactive, person-centered care which focuses on individuals' well-being. However, this transition will only be made possible through scientific innovation. Next-generation technologies will be the key to developing affordable and accessible care, while also lowering the costs of healthcare. A promising solution to this challenge is low-cost continuous health monitoring; this approach allows for effective screening, analysis, and diagnosis and facilitates proactive medical intervention. Urine has great promise for being a key resource for health monitoring; unlike blood, it can be collected effortlessly on a daily basis without pain or the need for special equipment. Unfortunately, the commercial rapid urine analysis tests that exist today can only go so far-this is where the promise of microfluidic devices lies. Microfluidic devices have a proven record of being effective analytical devices, capable of controlling the flow of fluid samples, containing reaction and detection zones, and displaying results, all within a compact footprint. Moving past traditional glass- and polymer-based microfluidics, paper-based microfluidic devices possess the same diagnostic ability, with the added benefits of facile manufacturing, low-cost implementation, and disposability. Hence, we review the recent progress in the application of paper-based microfluidics to urine analysis as a solution to providing continuous health monitoring for proactive care. First, we present important considerations for point-of-care diagnostic devices. We then discuss what urine is and how paper functions as the substrate for urine analysis. Next, we cover the current commercial rapid tests that exist and thereby demonstrate where paper-based microfluidic urine analysis devices may fit into the commercial market in the future. Afterward, we discuss various fabrication techniques that have been recently developed for paper-based microfluidic devices. Transitioning from fabrication to implementation, we present some of the clinically implemented urine assays and their importance in healthcare and clinical diagnosis, with a focus on paper-based microfluidic assays. We then conclude by providing an overview of select biomarker research tailored towards urine diagnostics. This review will demonstrate the applicability of paper-based assays for urine analysis and where they may fit into the commercial healthcare market.

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.

Hyperamylasemia is associated with increased intestinal permeability in patients undergoing diagnostic oral double-balloon enteroscopy

AIM: To investigate the correlations between serum amylase levels, intestinal permeability (IP), and pancreatic injury and to explore the mechanisms responsible for hyperamylasemia in double-balloon enteroscopy (DBE).

METHODS: A prospective study was conducted in 20 patients who underwent DBE from August 1, 2008 to February 28, 2009. Serum amylase was examined 0, 2, 6 and 24 h post-DBE, C-reactive protein and lipase were examined at 24 h, and urine lactulose, mannitol, and trypsinogen-II (TRY-II) levels were measured at 6 h. Lactulose/mannitol ratio indicated IP, and TRY-IIindicated pancreatic injuries. Procedure duration and enteroscope insertion length were recorded.

RESULTS: Twelve patients underwent oral DBE (M:F, 5:7; mean age 50.42 ± 11.11 years) and 8 underwent anal DBE (M:F, 5:3; mean age 44.75 ± 12.66 years). They all showed significantly increased post-DBE serum amylase. Amylase and lipase levels were higher in the oral DBE group (P < 0.05). Hyperamylasemia was diagnosed in 9 (75.0%) patients undergoing oral DBE. Only patients receiving oral DBE showed increased post-procedure IP, which correlated with increased serum amylase (r = 0.611, P = 0.035) and procedure duration (r = 0.668, P = 0.018). Adverse events included one oral case with pancreatic injury (elevated TRY-II) and two cases of abdominal discomfort in each group. Pancreatitis was not reported.

CONCLUSION: Hyperamylasemia correlates with increased IP and clinically undetectable pancreatic injuries. DBE could cause intestinal mucosa damage, which may result in IP elevation and increased amylase absorption, necessitating improvements and standardization of DBE methods.

Urinary trypsinogen-2 for diagnosing acute pancreatitis: a meta-analysis

BACKGROUND

Currently, serum amylase and lipase are the most popular laboratory markers for early diagnosis of acute pancreatitis with reasonable sensitivity and specificity. Urinary trypsinogen-2 (UT-2) has been increasingly used but its clinical value for the diagnosis of acute pancreatitis and post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis has not yet been systematically assessed.

DATA SOURCES

A comprehensive search was carried out using PubMed (MEDLINE), Embase, and Web of Science for clinical trials, which studied the usefulness of UT-2 as a diagnostic marker for acute pancreatitis. Sensitivity, specificity and the diagnostic odds ratios (DORs) with 95% confidence interval (CI) were calculated for each study and were compared with serum amylase and lipase. Summary receiver-operating curves were conducted and the area under the curve (AUC) was evaluated.

RESULTS

A total of 18 studies were included. The pooled sensitivity and specificity of UT-2 for the diagnosis of acute pancreatitis were 80% and 92%, respectively (AUC=0.96, DOR=65.63, 95% CI: 31.65-139.09). The diagnostic value of UT-2 was comparable to serum amylase but was weaker than serum lipase. The pooled sensitivity and specificity for the diagnosis of post-ERCP pancreatitis were 86% and 94%, respectively (AUC=0.92, DOR=77.68, 95% CI: 24.99-241.48).

CONCLUSIONS

UT-2 as a rapid test could be potentially used for the diagnosis of post-ERCP pancreatitis and to an extent, acute pancreatitis. Further studies are warranted to confirm these results.

Validity of the urinary trypsinogen-2 test in the diagnosis of acute pancreatitis

OBJECTIVES

A simple urinary trypsinogen-2 test was evaluated for the diagnosis of acute pancreatitis.

METHODS

This prospective multicenter study enrolled consecutive patients with acute abdominal pain who presented to the emergency department or who were hospitalized at 1 of 21 medical institutions in Japan. Patients were tested with urinary trypsinogen-2 dipstick test and a quantitative trypsinogen-2 assay, and these values were compared with serum amylase and lipase findings.

RESULTS

A total of 412 patients were enrolled. The trypsinogen-2 dipstick test was positive in 107 of 156 patients with acute pancreatitis (sensitivity, 68.6%) and in 33 of 256 patients with nonpancreatic abdominal pain (specificity, 87.1%). The sensitivity for the diagnosis of pancreatitis caused by alcohol and gallstones by the dipstick test was 72.2% and 81.8%, respectively, which was much higher than those associated with amylase testing. There are several degrees of positivity within the urinary trypsinogen-2 dipstick test. Modification of the cutoff point such that positive (+) and most positive (++) results were interpreted as a positive result, the specificity and positive likelihood ratio increased to 92.2% and 7.63, respectively.

CONCLUSIONS

This simple, rapid, easy, and noninvasive urinary trypsinogen-2 test can diagnose or rule out most cases of acute pancreatitis.

Urine analysis in microfluidic devices

Microfluidics has attracted considerable attention since its early development in the 1980s and has experienced rapid growth in the past three decades due to advantages associated with miniaturization, integration and automation. Urine analysis is a common, fast and inexpensive clinical diagnostic tool in health care. In this article, we will be reviewing recent works starting from 2005 to the present for urine analysis using microfluidic devices or systems and to provide in-depth commentary about these techniques. Moreover, commercial strips that are often treated as chips and their readers for urine analysis will also be briefly discussed. We start with an introduction to the physiological significance of various components or measurement standards in urine analysis, followed by a brief introduction to enabling microfluidic technologies. Then, microfluidic devices or systems for sample pretreatments and for sensing urinary macromolecules, micromolecules, as well as multiplexed analysis are reviewed, in this sequence. Moreover, a microfluidic chip for urinary proteome profiling is also discussed, followed by a section discussing commercial products. Finally, the authors' perspectives on microfluidic-based urine analysis are provided. These advancements in microfluidic techniques for urine analysis may improve current routine clinical practices, particularly for point-of-care (POC) applications.

Urinary trypsinogen-2 dipstick in acute pancreatitis

OBJECTIVES

In acute pancreatitis (AP), rapid diagnosis and early treatment are of importance for clinical outcome. Urinary trypsinogen-2 has been suggested as a promising diagnostic marker; however, studies using the urinary trypsinogen-2 dipstick test (UTDT) have provided varying results.

METHODS

The study was set to evaluate the use of the UTDT (Actim Pancreatitis; Medix Biochemica, Kauniainen, Finland, Medinor, Roskilde, Denmark) in apparent first attack of AP in daily clinics. Acute pancreatitis was defined as more than a 3-fold increase in plasma amylase levels. We included 75 patients admitted with AP. Thirty-four patients with acute abdominal pain of causes other than AP served as a control group.

RESULTS

In 58 of 75 patients, the UTDT result was positive, giving a sensitivity of 77% (95% confidence interval [CI]: 66%-86%). In severe cases, the sensitivity improved to 87% (95% CI: 69%-96%). In 33 of 34 controls, the test result was negative, giving a specificity of 97% (95% CI: 84%-99.9%).

CONCLUSION

The UTDT had a low sensitivity but high specificity. These results do not support the UTDT to replace standard plasma amylase for the diagnosis of apparent first attack of AP. However, the test demonstrated an adequate sensitivity to be used for rapid early screening of AP in daily clinics.

New diagnostic criteria of acute pancreatitis

Practical guidelines for the diagnosis of acute pancreatitis are presented so that a rapid and adequate diagnosis can be made. When acute pancreatitis is suspected in patients with acute onset of abdominal pain and tenderness mainly in the upper abdomen, the diagnosis of acute pancreatitis is made on the basis of elevated levels of pancreatic enzymes in the blood and/or urine. Furthermore, other acute abdominal diseases are ruled out if local findings associated with pancreatitis are confirmed by diagnostic imaging. According to the diagnostic criteria established in Japan, patients who present with two of the following three manifestations are diagnosed as having acute pancreatitis: characteristic upper abdominal pain, elevated levels of pancreatic enzymes, and findings of ultrasonography (US), CT or MRI suggesting acute pancreatitis. Detection of elevated levels of blood pancreatic enzymes is crucial in the diagnosis of acute pancreatitis. Measurement of blood lipase is recommended, because it is reported to be superior to all other pancreatic enzymes in terms of sensitivity and specificity. For measurements of the blood amylase level widely used in Japan, it should be cautioned that, because of its low specificity, abnormal high values are also often obtained in diseases other than pancreatitis. The cut-off level of blood pancreatic enzymes for the diagnosis of acute pancreatitis is not able to be set because of lack of sufficient evidence and consensus to date. CT study is the most appropriate procedure to confirm image findings of acute pancreatitis. Elucidation of the etiology of acute pancreatitis should be continued after a diagnosis of acute pancreatitis. In the process of the etiologic elucidation of acute pancreatitis, judgment whether it is gallstone-induced or not is most urgent and crucial for deciding treatment policy including the assessment of whether endoscopic papillary treatment should be conducted or not. The diagnosis of gallstone-induced acute pancreatitis can be made by combining detection of elevated levels of bilirubin, transamylase (ALT, AST) and ALP detected by hematological examination and the visualization of gallstones by US.

Early diagnosis and prediction of severity in acute pancreatitis using the urine trypsinogen-2 dipstick test: a prospective study

AIM

To evaluate the use of the trypsinogen-2 dipstick (Actim Pancreatitis) test for early diagnosis and prediction of severity in acute pancreatitis (AP).

METHODS

Ninety-two patients with AP were included in this study. The control group was 25 patients who had acute abdominal pain from non-pancreatic causes. Urine trypsinogen-2 dipstick test (UTDT) and conventional diagnostic tests were performed in all patients. Patients were divided by the Atlanta classification into two groups as having mild or severe pancreatitis.

RESULTS

UTDT was positive in 87 (94.6%) of the AP patients and in two (8%) controls (P < 0.05). Positive UTDT was found in 61 (92.4%) of 66 (71.7%) patients with mild pancreatitis and in all (100%) of the 26 (28.3%) with severe pancreatitis (P > 0.05). UTDT positivity lasted longer in severe pancreatitis compared with that in mild pancreatitis (6.2 +/- 2.5 d vs 2.0 +/- 1.43 d, P < 0.05). The sensitivity, specificity, positive predictive value, negative predictive value (NPV), positive likelihood ratio (PLR) and negative likelihood ratio (NLR) of UTDT were 91%, 72%, 96.6%, 70.4%, 3.4 and 0.1, respectively.

CONCLUSION

UTDT is a simple, rapid and reliable method for use on admission. It has high specificity and low NLR for early diagnosis and prediction of severity in AP. However, its relatively low NPV does not allow trypsinogen-2 dipstick test to be a stand-alone tool for diagnosis of acute pancreatitis; the use of other conventional diagnostic tools remains a requirement.

Early diagnosis and prediction of severity in acute pancreatitis using the urine trypsinogen-2 dipstick test: A prospective study

AIM: To evaluate the use of the trypsinogen-2 dipstick (Actim Pancreatitis) test for early diagnosis and prediction of severity in acute pancreatitis (AP).

METHODS: Ninety-two patients with AP were included in this study. The control group was 25 patients who had acute abdominal pain from non-pancreatic causes. Urine trypsinogen-2 dipstick test (UTDT) and conventional diagnostic tests were performed in all patients. Patients were divided by the Atlanta classification into two groups as having mild or severe pancreatitis.

RESULTS: UTDT was positive in 87 (94.6%) of the AP patients and in two (8%) controls (P < 0.05). Positive UTDT was found in 61 (92.4%) of 66 (71.7%) patients with mild pancreatitis and in all (100%) of the 26 (28.3%) with severe pancreatitis (P > 0.05). UTDT positivity lasted longer in severe pancreatitis compared with that in mild pancreatitis (6.2 ± 2.5 d vs 2.0 ± 1.43 d, P < 0.05). The sensitivity, specificity, positive predictive value, negative predictive value (NPV), positive likelihood ratio (PLR) and negative likelihood ratio (NLR) of UTDT were 91%, 72%, 96.6%, 70.4%, 3.4 and 0.1, respectively.

CONCLUSION: UTDT is a simple, rapid and reliable method for use on admission. It has high specificity and low NLR for early diagnosis and prediction of severity in AP. However, its relatively low NPV does not allow trypsinogen-2 dipstick test to be a stand-alone tool for diagnosis of acute pancreatitis; the use of other conventional diagnostic tools remains a requirement.

Pancreatits after endoscopic retrograde cholangio-pancreatography

Pancreatitis is the most common complication after endoscopic retrograde cholangio-pancreatography (ERCP); the reported incidence of this complication varies from less than 1% to 40%, but a rate of 4%-8% is reported in most prospective studies involving non-selected patients. Differences in criteria for defining pancreatitis, methods of data collection, and patient populations (i.e. number of high-risk patients included in the published series) are factors that are likely to affect the varying rates of post-ERCP pancreatitis. The severity of post-ERCP pancreatitis (PEP) can range from a minor inconvenience with one or two days of added hospitalization with full recovery to a devastating illness with pancreatic necrosis, multiorgan failure, permanent disability, and even death. Although, most episodes of PEP are mild (about 90%), a small percentage of patients (about 10%) develop moderate or severe pancreatitis. In the past, PEP was often viewed as an unpredictable and unavoidable complication, with no realistic strategy for its avoidance. New data have aided in stratification of patients into PEP risk categories and new measures have been introduced to decrease the risk of PEP. As most ERCPs are performed on an outpatient basis, the majority of patients will not develop PEP and can be discharged. Alternatively, early detection of those patients who will go on to develop PEP can guide decisions regarding hospital admission and aggressive management. In the last decade, great efforts have been addressed toward prevention of this complication. Points of emphasis have included technical measures, pharmacological prophylaxis, and patient selection. This review provides a comprehensive, evidence-based assessment of published data on PEP and current suggestions for its avoidance.

USEFULNESS OF INFRARED SPECTROSCOPY IN DIAGNOSIS OF ACUTE PANCREATITIS

BACKGROUND

The lack of a gold standard for the diagnosis of acute pancreatitis remains a problem. Our aim was to evaluate whether infrared spectroscopy of serum can establish the diagnosis of acute pancreatitis.

METHODS

Sixty-four patients with acute pancreatitis, 112 patients with non-pancreatic acute abdomen and 40 healthy subjects were studied. In addition to serum infrared spectral analysis, serum concentrations of amylase and lipase were measured on admission.

RESULTS

Infrared spectroscopy based on serum absorption patterns in the range 800-1000 nm successfully distinguished acute pancreatitis from acute abdominal disorders of extrapancreatic origin and from control specimens. The sensitivity, specificity and positive and negative predictive values of infrared spectroscopy on admission were 91, 91, 85, and 94%, respectively. Within 24 h of onset of symptoms, infrared spectroscopy, lipase and amylase showed similar areas under the ROC curves for infrared spectra of serum (0.93), lipase (0.96) and amylase (0.91).

CONCLUSIONS

The successful classification of infrared spectra in patients with acute pancreatitis implies that the pathophysiology of disease alters the composition of the specimen in a characteristic fashion--in this case the serum make-up reflects the presence of acute pancreatitis.

Point-of-care Urine Trypsinogen Testing for the Diagnosis of Pancreatitis

OBJECTIVES

To assess a point-of-care (POC) urine trypsinogen (UT) test for the diagnosis of pancreatitis in the emergency department (ED).

METHODS

This was a prospective cohort study of a convenience sample of patients presenting to the ED with abdominal pain or symptoms suggestive of pancreatitis. A 3-minute POC UT test (Actim Pancreatitis; Medix Biochemica, Kauniainen, Finland) was compared with plasma lipase and amylase measurements, imaging results when performed, and final discharge diagnoses. The criterion standard was a final discharge diagnosis of acute pancreatitis.

RESULTS

Of 191 patients included in this study, 17 patients were diagnosed with either acute or acute-on-chronic pancreatitis. The sensitivity and specificity of UT for acute pancreatitis were, respectively, 100% (95% confidence interval [CI] = 77% to 100%) and 96% (95% CI = 92% to 98%). Seven of the 17 patients with pancreatitis (41%) had diagnostic findings on CT and positive UT tests but had nondiagnostic plasma lipase and amylase levels.

CONCLUSIONS

A POC UT screening test for pancreatitis in the ED compared favorably with plasma lipase and amylase levels. Future studies should be performed to explore whether this test in the ED setting has better clinical utility than plasma lipase or amylase.

Detection of postoperative pancreatitis after pancreatic surgery by urine trypsinogen strip test

Background

The urine trypsinogen strip test has been used successfully in the diagnosis of pancreatitis of various aetiologies, but has not been studied in postoperative pancreatitis. The aim of this study was to evaluate this test for the diagnosis of postoperative pancreatitis after pancreatic resection.

Methods

Fifty patients undergoing pancreatic resection were included. The urine trypsinogen strip test was done daily during the first postoperative week, blood was analysed before and 4, 6 and 10 days after surgery, and amylase activity in the drainage fluid was measured on days 4 and 6. Patients underwent computed tomography (CT) before operation and on days 2 and 6 afterwards.

Results

Thirteen patients (26 per cent) developed CT-detected pancreatitis after operation. In 12 of these patients pancreatitis was detected on the second postoperative day. The urine trypsinogen test was positive in all 13 patients with postoperative pancreatitis, and was already positive on the first day after surgery in 12. The sensitivity, specificity, and positive and negative predictive values of the trypsinogen strip test in detection of postoperative pancreatitis were 100, 92, 81 and 100 per cent respectively. In receiver–operator characteristic analysis the area under the curve (AUC) was higher for the urine trypsinogen strip test (AUC 0·959) than for a serum amylase level more than two (AUC 0·731) or three times (AUC 0·654) above the upper normal range in the diagnosis of postoperative pancreatitis. Patients whose recovery was complicated by pancreatic fistula, detected by drain output measurements on day 6, more often had a positive urine trypsinogen test than patients without a fistula (11 of 12 versus five of 38; P &lt; 0·001).

Conclusion

This study suggests that the urine trypsinogen strip test might be a valuable method for diagnosis of pancreatitis after pancreatic surgery.

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.

O papel da avaliação inicial simplificada no prognóstico da pancreatite aguda

OBJETIVO: Correlacionar a avaliação clínico-laboratorial inicial simplificada com a gravidade da pancreatite aguda e a presença de necrose. MÉTODO: Foi realizado um estudo retrospectivo dos pacientes com diagnóstico final de PA internados no Hospital Universitário Clementino Fraga Filho - UFRJ entre janeiro de 1990 e agosto de 2002. Foi considerado apenas o primeiro episódio de cada paciente. Os dados obtidos foram submetidos a análise estatística. Foram estudados 164 pacientes onde a idade média foi de 43,7 anos. RESULTADOS: A etiologia biliar foi a mais freqüente com 43,9% dos casos. A incidência de necrose foi de 21,3% e a mortalidade global de 23,2%. Observamos que a ausência de taquicardia na admissão estava associada à forma branda da doença, e que os níveis plasmáticos de uréia e creatinina elevados na admissão estão associados à forma grave da doença, e a hiperglicemia (121mg/dl) à necrose pancreática. CONCLUSÕES: A avaliação inicial simplificada ainda tem espaço, embora que limitado, no acompanhamento do paciente com PA.

Clinical value of rapid urine trypsinogen-2 test strip, urinary trypsinogen activation peptide, and serum and urinary activation peptide of carboxypeptidase B in acute pancreatitis

AIM

To assess the usefulness of urinary trypsinogen-2 test strip, urinary trypsinogen activation peptide (TAP), and serum and urine concentrations of the activation peptide of carboxypeptidase B (CAPAP) in the diagnosis of acute pancreatitis.

METHODS

Patients with acute abdominal pain and hospitalized within 24 h after the onset of symptoms were prospectively studied. Urinary trypsinogen-2 was considered positive when a clear blue line was observed (detection limit 50 microg/L). Urinary TAP was measured using a quantitative solid-phase ELISA, and serum and urinary CAPAP by a radioimmunoassay method.

RESULTS

Acute abdominal pain was due to acute pancreatitis in 50 patients and turned out to be extrapancreatic in origin in 22 patients. Patients with acute pancreatitis showed significantly higher median levels of serum and urinary CAPAP levels, as well as amylase and lipase than extrapancreatic controls. Median TAP levels were similar in both groups. The urinary trypsinogen-2 test strip was positive in 68% of patients with acute pancreatitis and 13.6% in extrapancreatic controls (P<0.01). Urinary CAPAP was the most reliable test for the diagnosis of acute pancreatitis (sensitivity 66.7%, specificity 95.5%, positive and negative predictive values 96.6% and 56.7%, respectively), with a 14.6 positive likelihood ratio for a cut-off value of 2.32 nmol/L.

CONCLUSION

In patients with acute abdominal pain, hospitalized within 24 h of symptom onset, CAPAP in serum and urine was a reliable diagnostic marker of acute pancreatitis. Urinary trypsinogen-2 test strip showed a clinical value similar to amylase and lipase. Urinary TAP was not a useful screening test for the diagnosis of acute 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.

Rapid urinary trypsinogen-2 test strip in the diagnosis of acute pancreatitis

OBJECTIVES

Early diagnosis of acute pancreatitis remains a challenge. A rapid dipstick screening test for acute pancreatitis has been developed. This prospective study was designed to evaluate the diagnostic value and time course of the rapid urinary trypsinogen-2 test strip in acute pancreatitis, with comparisons with serum amylase and serum lipase.

METHODS

A total of 165 patients with acute abdominal pain (67 with acute pancreatitis and 98 with other acute abdominal diseases) attending our emergency unit were included. All patients were tested with the urinary trypsinogen-2 test strip, and serum amylase and serum lipase concentrations were determined simultaneously. To measure the time course of the urinary trypsinogen-2 test, 32 patients with acute pancreatitis were tested with a urinary trypsinogen-2 test strip on days 1, 2, 3, and 4 after admission.

RESULTS

Using a cutoff level of 50 microg/L for urinary trypsinogen-2, the sensitivity, specificity, and accuracy of the urinary trypsinogen-2 test strip for recognition of acute pancreatitis were 89.6%, 85.7%, and 87.3%, respectively. The diagnostic accuracy rates of serum amylase and serum lipase were 88.5% and 93.3%, using cutoff values of 3 times the upper normal limits for serum amylase and serum lipase, respectively. All but one of the 17 patients with severe acute pancreatitis was detected by the test strip (sensitivity, 94.1%). The time-course study of the urinary trypsinogen-2 test strip revealed that the sensitivity on days 1, 2, 3, and 4 was 90.6%, 81.2%, 59.4%, and 50%, respectively. There was no significant difference in the sensitivity between urinary trypsinogen-2 and serum lipase; however, the sensitivity values of serum lipase were significantly higher than those of serum amylase from days 1 to 4.

CONCLUSION

The rapid urinary trypsinogen-2 test is a reliable and simple method for the early diagnosis of acute pancreatitis. A positive test identifies patients in need of further diagnostic measures. The urinary trypsinogen-2 test can be performed in health care units where laboratory testing facilities are not immediately available.

Useful markers for predicting severity and monitoring progression of acute pancreatitis

BACKGROUND

The main problem in staging acute pancreatitis is the lack of accurate predictors of disease severity and of markers for progression of acute pancreatitis.

METHODS

We reviewed the literature for all candidate markers of acute pancreatitis and graded their usefulness and practicability for prediction of severe pancreatitis and for monitoring disease progression.

RESULTS

Several markers can differentiate mild and severe cases of acute pancreatitis with a high positive predictive value. Trypsinogen activation peptide and procalcitonin show significant differences in patients with mild and severe disease already on admission. While most parameters peak early and decrease rapidly thereafter, C-reactive protein (CRP), phospholipase A(2), procalcitonin and serum amyloid A are reliable predictors with persistently elevated levels in severe disease. CRP is still the reference parameter of all predictors indicating severe disease and pancreatic necrosis. So far, no single parameter has been developed which is suitable for early prediction of infected pancreatic necrosis.

CONCLUSION

Of all markers available today, CRP is the 'gold standard' in predicting the severity of acute pancreatitis, but procalcitonin seems to be a promising tool to monitor the progression of the disease. CRP has already been established in clinical routine. For procalcitonin, a practicable assay is also available and could easily be adopted into clinical routine.

Calcitonin precursors in the prediction of severity of acute pancreatitis on the day of admission

BACKGROUND

Calcitonin precursors are sensitive markers of inflammation and infection. The aim of this study was to evaluate the role of plasma calcitonin precursor levels on the day of admission in the prediction of severity of acute pancreatitis, and to compare this with the Acute Physiology And Chronic Health Evaluation (APACHE) II scoring system.

METHODS

Plasma concentrations of calcitonin precursors were determined on admission in 69 patients with acute pancreatitis. APACHE II scores were calculated on admission. Attacks were classified as mild (n = 55) or severe (n = 14) according to the Atlanta criteria. Plasma calcitonin precursor levels were determined with a sensitive radioimmunoassay.

RESULTS

On the day of hospital admission, plasma levels of calcitonin precursors were significantly greater in patients with a severe attack compared with levels in those with a mild attack of pancreatitis (median 64 versus 25 fmol/ml; P = 0.014), but the APACHE II scores were no different (median 9 versus 8; P = 0.2). The sensitivity, specificity, positive predictive and negative predictive values, and accuracy for the prediction of severe acute pancreatitis were 67, 89, 57, 93 and 85 per cent respectively for plasma calcitonin precursor levels higher than 48 fmol/ml, and 69, 45, 23, 86 and 50 per cent respectively for an APACHE II score greater than 7. Differences in the specificity and accuracy of the two prognostic indicators were significant (P < 0.001 and P = 0.001 respectively). A plasma calcitonin precursor concentration of more than 160 fmol/ml on admission was highly accurate (94 per cent) in predicting the development of septic complications and death.

CONCLUSION

The assay of plasma calcitonin precursors on the day of admission to hospital has the potential to provide a more accurate prediction of the severity of acute pancreatitis than the APACHE II scoring system.

A critical evaluation of laboratory tests in acute pancreatitis

An ideal laboratory test in the evaluation of a patient with acute pancreatitis (AP) should, in addition to accurately establishing the diagnosis of AP, provide early assessment of its severity and identify the etiology. None of the tests available today meet all these criteria, and presently there is no biochemical test that can be considered the "gold standard" for the diagnosis and assessment of severity of AP. In the diagnosis of AP, serum amylase and lipase remain important tests. Advantages of amylase estimation are its technical simplicity, easy availability, and high sensitivity. However, its greatest disadvantage is its low specificity. A normal amylase would usually exclude the diagnosis of AP, with the exception of AP secondary to hyperlipidemia, acute exacerbation of chronic pancreatitis, and when the estimation of amylase is delayed in the course of the disease. The major advantage of lipase is an increased sensitivity in acute alcoholic pancreatitis and in patients who initially present to the emergency room days after the onset of the disease, as lipase remains elevated longer than amylase. Although once considered to be specific for AP, nonspecific elevations of lipase have been reported in almost as many disorders as amylase, thus decreasing its specificity. Simultaneous estimation of amylase and lipase does not improve the accuracy. Other enzymes for the diagnosis of AP--pancreatic isoamylase, immunoreactive trypsin, and elastase--are more cumbersome and expensive and have no clear role in the diagnosis of AP. No enzyme assay has a predictive role in determining the severity or etiology of AP. Once the diagnosis of AP is established, daily measurements of enzymes have no value in assessing the clinical progress of the patient or ultimate prognosis and should be discouraged. A host of new serological and urinary markers have been investigated in the last few years. Their main use is in predicting the severity of AP. At present, serum C-reactive protein at 48 h is the best available laboratory marker of severity. Urinary trypsinogen activation peptides within 12-24 h of onset of AP are able to predict the severity but are not widely available. Serum interleukins 6 and 8 seem promising but remain experimental.

New laboratory tests in acute pancreatitis

Acute pancreatitis (AP) is a common disease with wide variation of severity. The diagnosis of AP is usually based on high serum amylase or lipase values but the accuracy of these methods is considered unsatisfactory. One in five of the patients develops a severe disease and carries a considerable risk of development of organ failure and high mortality. Early detection of patients with severe AP and especially those with increased risk of organ failure is importance since such patients seem to benefit from treatment in an intensive care unit started as soon as possible after presentation. In addition to enzymological methods, increasing interest has been focused on laboratory markers reflecting the level of inflammatory response in AP. At present, in routine clinical work the most commonly used severity marker is serum C-reactive protein, the concentration of which rises too slowly to be used for early prediction of severity. New therapies aiming at modifying the course of systemic inflammation in AP are being developed and therefore monitoring the patient's immune inflammatory status is needed. In this review article we present the current knowledge of laboratory tests, which has been evaluated for diagnostic and prognostic purposes in AP.

Laboratory diagnostic tests in acute pancreatitis

The diagnosis of acute pancreatitis depends on a combination of clinical assessment and laboratory testing. Although the serum amylase is the cornerstone laboratory test used in establishing the diagnosis of acute pancreatitis, there are limitations in the sensitivity and specificity that may be important for the clinician to recognize. The serum lipase level may be especially useful in patients with alcohol-induced acute pancreatitis. A new urinary test strip that uses trypsinogen-2 may have a role in establishing the diagnosis of acute pancreatitis. In addition, several new laboratory tests and new interpretations of old laboratory tests may assist in establishing the etiology and severity of acute pancreatitis. This review summarizes important aspects of standard laboratory tests and novel laboratory approaches in establishing the diagnosis, etiology, and severity of acute pancreatitis.

Predicting the Severity of Acute Pancreatitis by Rapid Measurement of Trypsinogen-2 in Urine

Background: Early identification of patients at risk of developing a severe attack of acute pancreatitis (AP) is of great importance because rapid therapeutic interventions improve outcome. At a cutoff of 50 μg/L, trypsinogen-2 measured by a rapid urinary dipstick is a sensitive and specific diagnostic test in AP. The trypsinogen-2 concentration correlates with the severity of the disease, and a test with a higher cutoff might therefore be useful for prediction of disease severity.

Methods: We increased the detection limit of the urinary trypsinogen-2 test strip (Actim Pancreatitis) from 50 μg/L to 2000 μg/L and evaluated the prognostic value of this test. The results were compared with those obtained with serum C-reactive protein and the acute physiology and chronic health evaluation II (APACHE II) score. The study population consisted of 150 consecutive patients with AP (42 with severe disease).

Results: The sensitivity of the rapid urinary test strip (detection limit, 2000 μg/L) for prediction of severe AP, both on admission and at 24 h, was 62%; specificities were 87% and 85%, respectively, positive predictive values were 65% and 62%, and negative predictive values were 85% and 85%. C-Reactive protein had a sensitivity of only 38% on admission, but at 24 h, it was 83%; specificities were 90% and 70%, respectively, whereas positive predictive values were 59% and 52%, and NPVs were 79% and 91%, respectively. On admission the positive-likelihood ratio for the urinary trypsinogen-2 test strip was 4.8, and at 24 h it was 4.2; for C-reactive protein, the values were 3.7 and 2.7, respectively.

Conclusions: The urinary trypsinogen-2 dipstick is a simple and rapid method for prediction of severe acute pancreatitis.

Acute pancreatitis

Acute pancreatitis is a common disease. As knowledge of its pathophysiology improves, evidence is found to confirm and refute present management and also to suggest new approaches. This article addresses some of these areas in the context of the management of acute pancreatitis.