Elastase-1 (EC 220.127.116.11) is secreted as proelastase and activated by trypsin. We distinguish between elastase-1 (Mr 30,000; anodic fraction), which occurs in serum as a free-form and as a complex with an α1-proteinase inhibitor, and elastase-2 (Mr 25,000; cathodic fraction). The enzyme is secreted into the pancreatic juice, which is then secreted into the duodenum and the protein sequence selected for immunochemical detection is not degraded during intestinal passage. In inflammatory processes, there is also retrograde release into the bloodstream, and quantification of serum levels of human pancreatic elastase is a suitable marker of acute pancreatitis, such as in post-ERCP and pancreatic cancer. Elastase-1 (determined by ELISA) has the highest specificity and sensitivity of all pancreatic enzymes for pancreatic cancer. Elastase-1 levels are elevated in both acute and chronic recurrent pancreatitis, and the increase persists longer and correlates better with clinical status than α-amylase levels. RIA methods with 125 I-labeled elastase or newer ELISA techniques utilizing a monoclonal antibody specific to elastase-1 are used to determine elastase-1. Elastase-1 (determined by ELISA) has the highest specificity and sensitivity of all pancreatic enzymes for pancreatic cancer. The reference range (for the RIA methodology) is 1.3-4.3 µg / l. The latest innovation in the determination of serum elastase-1 is based on a latex immunoassay.
Determination of elastase-1 (EL-1) in stool[edit | edit source]
Human pancreatic elastase-1 is synthesized by pancreatic acinar cells. The enzyme is secreted into the pancreatic juice, which is then secreted into the duodenum and the protein sequence selected for immunochemical detection is not degraded during intestinal passage. The detection of elastase in stool therefore is of high diagnostic value. Unlike the chromogenic method of determining fecal chymotrypsin, the determination of fecal lipase is not important. Human pancreatic elastase-1 activity in stool samples reflects the degree of exocrine pancreatic function. Recent applications recommend the determination of pancreatic elastase-1 in duodenal juice in a stimulated functional test. Stool elastase-1 determination is of clinical importance in the differential diagnosis of malabsorption syndrome, as a screening test for pancreatic disease, and for long-term follow-up of patients with chronic pancreatitis. The laboratory method is based on ELISA with a monoclonal (or polyclonal) antibody specific to human pancreatic elastase. The stool sample is homogenized in the extraction buffer solution, and after a dilution of 1: 500, a standard ELISA procedure on a microtiter plate with POD-streptavidin detection is performed. The kit contains 5 calibration standards in the range of 0.3-10.0 ng / mL.
The reference values are 200–500 µg / g stool, the cut-off range is 100–200 µg / g, severe pancreatic insufficiency is determined at values <100 µg / g stool. Immunochemical determination of elastase-1 is not affected by colonic passage, replacement therapy, or other factors that affect the enzymatic determination of chymotrypsin in the stool. The specificity of the method is 93%, while the sensitivity reaches 100% for severe pancreatic insufficiency and 87% for mild and light forms. This test is commonly used in pediatrics to diagnose cystic fibrosis with a specificity and sensitivity of almost 100%. False reduction in the value may be due to dilution during diarrhea (due to higher water content).
References[edit | edit source]
Literature[edit | edit source]
- KAPETANOS, D, et al. The value of serum amylase and elastase measurements in the prediction of post-ERCP acute pancreatitis. Hepatogastroenterology. 2007, vol. 54, no. 74, s. 556-60, ISSN 0172-6390. PMID: 17523321.
- WU, D, et al. Evaluating the role of serum elastase 1 in the diagnosis of pancreatic cancer. Chin J Dig Dis. 2006, vol. 7, no. 2, s. 117-20, ISSN 1443-9611 (Print), 1443-9573 (Electronic). PMID: 16643340.
- WILSON, RB, et al. Serum elastase in the diagnosis of acute pancreatitis: a prospective study. ANZ J Surg. 2005, vol. 75, no. 3, s. 152-6, ISSN 1445-1433 (Print), 1445-2197 (Electronic). PMID: 15777396.
- KEIM, V, et al. Evaluation of Pankrin, a new serum test for diagnosis of acute pancreatitis. Clin Chim Acta. 2003, vol. 332, no. 1-2, s. 45-50, ISSN 0009-8981 (Print), 1873-3492 (Electronic). PMID: 12763279.
- KATSANOS, KH, et al. The true value of serum elastase-1 in endoscopic retrograde cholangiopancreatography (ERCP). Eur J Intern Med. 2002, vol. 13, no. 5, s. 329-335, ISSN 0953-6205 (Print), 1879-0828 (Electronic). PMID: 12144913.
- OHDE, K, et al. Determination of elastase 1 in plasma or serum by latex turbidometric immunoassay with automatic analyzer. Rinsho Byori. 2002, vol. 50, no. 4, s. 376-80, ISSN 0047-1860. PMID: 12014017.
- MILLSON, CE, et al. A prospective study of serum pancreatic elastase-1 in the diagnosis and assessment of acute pancreatitis. Scand J Gastroenterol. 1998, vol. 33, no. 6, s. 664-8, ISSN 0036-5521 (Print), 1502-7708 (Electronic). PMID: 9669641.
- IKEI, S, et al. Blood concentrations of polymorphonuclear leucocyte elastase and interleukin-6 are indicators for the occurrence of multiple organ failures at the early stage of acute pancreatitis. J Gastroenterol Hepatol. 1998, vol. 13, no. 12, s. 1274-83, ISSN 0815-9319 (Print), 1440-1746 (Electronic). PMID: 9918438.
- KEIM, V, et al. Polyclonal pancreatic elastase assay is superior to monoclonal assay for diagnosis of acute pancreatitis. Clin Chem. 1997, vol. 43, no. 12, s. 2339-44, ISSN 0009-9147 (Print), 1530-8561 (Electronic). PMID: 9439452.
- IWASE, K, et al. Serial changes in plasma levels of pancreatic elastase 1 after pancreatic surgeries. Res Exp Med (Berl). 1995, vol. 195, no. 2, s. 93-100, ISSN 0300-9130. PMID: 7659839.
- SATAKE, K, et al. CA19-9 as a screening and diagnostic tool in symptomatic patients: the Japanese experience. Pancreas. 1994, vol. 9, no. 6, s. 703-6, ISSN 0885-3177 (Print), 1536-4828 (Electronic). PMID: 7846012.
- HOMMA, T, et al. The study of the mass screening of persons without symptoms and of the screening of outpatients with gastrointestinal complaints or icterus for pancreatic cancer in Japan, using CA19-9 and elastase-1 or ultrasonography. Int J Pancreatol. 1991, vol. 9, s. 119-24, ISSN 0169-4197. PMID: 1744437.
- LINDER, R, et al. Pancreatic elastase 1 after pancreatic transplantation. Pancreas. 1991, vol. 6, no. 1, s. 31-6, ISSN 0885-3177 (Print), 1536-4828 (Electronic). PMID: 1704632.
- PEZZILLI, R, et al. Serum pancreatic enzymes in the diagnosis of carcinoma of the pancreas. G Ital Oncol. 1989, vol. 9, no. 1, s. 7-13, ISSN 0392-128X. PMID: 2468605.
- TRAN, TC, et al. Pancreatic fibrosis correlates with exocrine pancreatic insufficiency after pancreatoduodenectomy. Dig Surg. 2008, vol. 25, no. 4, s. 311-8, ISSN 0253-4886 (Print). 1421-9883 (Electronic). PMID: 18818498.
- ERICKSON, JA, et al. Evaluation of a fecal pancreatic elastase-1 enzyme-linked immunosorbent assay: Assessment versus an established assay and implication in classifying pancreatic function. Clin Chim Acta. 2008, vol. 397, no. 1-2, s. 87-97, ISSN 0009-8981 (Print), 1873-3492 (Electronic). PMID: 18706899.
- LIEB, JG, et al. Pancreatic function testing: here to stay for the 21st century. World J Gastroenterol. 2008, vol. 14, no. 20, s. 3149-58, ISSN 1007-9327. PMID: 18506918.
- HAHN, JU, et al. Low fecal elastase 1 levels do not indicate exocrine pancreatic insufficiency in type-1 diabetes mellitus. Pancreas. 2008, vol. 36, no. 3, s. 274-8, ISSN 0885-3177 (Print) 1536-4828 (Electronic). PMID: 18362841.
- PEZZILLI, R, et al. Fecal calprotectin and elastase 1 determinations in patients with pancreatic diseases: a possible link between pancreatic insufficiency and intestinal inflammation. J Gastroenterol. 2007, vol. 42, no. 9, s. 754-60, ISSN 0944-1174 (Print), 1435-5922 (Electronic). PMID: 17876545.
- GILLAMS, A, et al. Correlation of MRCP quantification (MRCPQ) with conventional non-invasive pancreatic exocrine function tests. Abdom Imaging. 2008, vol. 33, no. 4, s. 469-73, ISSN 0942-8925 (Print), 1432-0509 (Electronic). PMID: 17653788.
- BOROWITZ, D, et al. Comparison of monoclonal and polyclonal ELISAs for fecal elastase in patients with cystic fibrosis and pancreatic insufficiency. J Pediatr Gastroenterol Nutr. 2007, vol. 44(2):219-23, no. 2, s. 219-23, ISSN 0277-2116 (Print), 1536-4801 (Electronic). PMID: 17255835.
- NARUSE, S, et al. Fecal pancreatic elastase: a reproducible marker for severe exocrine pancreatic insufficiency. J Gastroenterol. 2006, vol. 41, no. 9, s. 901-8, ISSN 0944-1174 (Print), 1435-5922 (Electronic). PMID: 17048055.
- KRECHLER, T, et al. Faecal elastase I--its use in diagnosis of chronic pancreatitis. Cas Lek Cesk. 2006, vol. 145, no. 6, s. 480-3, ISSN 0008-7335. PMID: 16836002.
- SENKAL, M, et al. Pancreatic elastase-1 in the stool for the determination of exocrine pancreas function of postoperative patients with early enteral nutrition -- a pilot study. Dtsch Med Wochenschr. 2006, vol. 131, no. 1-2, s. 13-6, ISSN 0012-0472 (Print), 1439-4413 (Electronic). PMID: 16374736.
- ELPHICK, DA, et al. Comparing the urinary pancreolauryl ratio and faecal elastase-1 as indicators of pancreatic insufficiency in clinical practice. Pancreatology. 2005, vol. 5, no. 2-3, s. 196-200, ISSN 1424-3903 (Print), 1424-3911 (Electronic). PMID: 15849489.
- MOLINARI, I, et al. Fecal chymotrypsin and elastase-1 determination on one single stool collected at random: diagnostic value for exocrine pancreatic status. Clin Biochem. 2004, vol. 37, no. 9, s. 758-63, ISSN 0009-9120 (Print), 1873-2933 (Electronic). PMID: 15329313.
- MIENDJE, Y, et al. Polyclonal versus monoclonal ELISA for the determination of fecal elastase 1: diagnostic value in cystic fibrosis and chronic pancreatic insufficiency. Clin Lab. 2004, vol. 50, no. 7-8, s. 419-24, ISSN 1433-6510. PMID: 15330510.
- STEVENS, T, et al. Analysis of pancreatic elastase-1 concentrations in duodenal aspirates from healthy subjects and patients with chronic pancreatitis. Dig Dis Sci. 2004, vol. 49, no. 9, s. 1405-11, ISSN 0163-2116 (Print), 1573-2568 (Electronic). PMID: 15481311.
- LANKISCH, PG. Now that fecal elastase is available in the United States, should clinicians start using it?. Curr Gastroenterol Rep. 2004, vol. 6, no. 2, s. 126-31, ISSN 1522-8037 (Print), 1534-312X (Electronic). PMID: 15191690.
- BRYDON, WG, et al. Limitations of faecal elastase-1 and chymotrypsin as tests of exocrine pancreatic disease in adults. Ann Clin Biochem. 2004, vol. 41, s. 78-81, ISSN 0004-5632 (Print), 1758-1001 (Electronic). PMID: 14713391.
- HARDT, PD, et al. The commercially available ELISA for pancreatic elastase 1 based on polyclonal antibodies does measure an as yet unknown antigen different from purified elastase 1. Binding studies and clinical use in patients with exocrine pancreatic insufficiency. Z Gastroenterol. 2003, vol. 41, no. 9, s. 903-6, ISSN 0044-2771 (Print), 1439-7803 (Electronic). PMID: 13130326.
- WALKOWIAK, J, et al. Comparison of faecal lipase test and faecal elastase-1 test in the assessment of exocrine pancreatic function in cystic fibrosis. Med Wieku Rozwoj. 2003, vol. 7, no. 2, s. 149-55, ISSN 1428-345X. PMID: 12878785.
- SONWALKAR, SA, et al. A prospective, comparative study of the para-aminobenzoic acid test and faecal elastase 1 in the assessment of exocrine pancreatic function. Aliment Pharmacol Ther. 2003, vol. 17, no. 3, s. 467-71, ISSN 0269-2813 (Print) 1365-2036 (Electronic). PMID: 12562462.
- TAKEDA, M, et al. Fecal elastase-1 test: clinical evaluation of a new noninvasive pancreatic function test. Rinsho Byori. 2002, vol. 50, no. 9, s. 893-8, ISSN 0047-1860. PMID: 12386968.
- WALKOWIAK, J, et al. Fecal elastase-1 is superior to fecal chymotrypsin in the assessment of pancreatic involvement in cystic fibrosis. Pediatrics. 2002, vol. 110, no. 1, s. e7-e7, ISSN 0031-4005 (Print), 1098-4275 (Electronic). PMID: 12093988.
- BEHARRY, S, et al. How useful is fecal pancreatic elastase 1 as a marker of exocrine pancreatic disease?. J Pediatr. 2002, vol. 141, no. 1, s. 84-90, ISSN 0022-3476 (Print), 1097-6833 (Electronic). PMID: 12091856.
- DOMINICI, R, et al. Fecal elastase-1 as a test for pancreatic function: a review. Clin Chem Lab Med. 2002, vol. 40, no. 4, s. 325-32, ISSN 1434-6621. PMID: 12059069.
- LÜTH, S, et al. Fecal elastase-1 determination: 'gold standard' of indirect pancreatic function tests?. Scand J Gastroenterol. 2001, vol. 36, no. 10, s. 1092-9, ISSN 0036-5521(Print), 1502-7708 (Electronic). PMID: 11589385.
- ICKS, A, et al. Low fecal elastase-1 in type I diabetes mellitus. Z Gastroenterol. 2001, vol. 39, no. 10, s. 823-30, ISSN 0044-2771 (Print), 1439-7803 (Electronic). PMID: 11605150.
- CARROCCIO, A, et al. Diagnostic accuracy of fecal elastase 1 assay in patients with pancreatic maldigestion or intestinal malabsorption: a collaborative study of the Italian Society of Pediatric Gastroenterology and Hepatology. Dig Dis Sci. 2001, vol. 46, no. 6, s. 1335-42, ISSN 0163-2116 (Print), 1573-2568 (Electronic). PMID: 11414313.
- NISSLER, K, et al. Pancreatic elastase 1 in feces of preterm and term infants. J Pediatr Gastroenterol Nutr. 2001, vol. 33, no. 1, s. 28-31, ISSN 0277-2116 (Print), 1536-4801 (Electronic). PMID: 11479404.
- LEUS, J, et al. Detection and follow up of exocrine pancreatic insufficiency in cystic fibrosis: a review. Eur J Pediatr. 2000, vol. 159, no. 8, s. 563-8, ISSN 0340-6199 (Print), 1432-1076 (Electronic). PMID: 10968231.
- PHILLIPS, IJ, et al. Faecal elastase 1: a marker of exocrine pancreatic insufficiency in cystic fibrosis. Ann Clin Biochem. 1999, vol. 36, no. 6, s. 739-42, ISSN 0004-5632 (Print), 1758-1001 (Electronic). PMID: 10586310.
- GULLO, L, et al. Fecal elastase 1 determination in chronic pancreatitis. Dig Dis Sci. 1999, vol. 44, no. 1, s. 210-3, ISSN 0163-2116 (Print), 1573-2568 (Electronic). PMID: 9952246.