Analysis of occluded pancreatic stents and juices in patients with chronic pancreatitis

Abstract

Analysis of occluded pancreatic stents and juices in patients with chronic pancreatitis Smits, M.E.; Groen, A.K.; Mok, K.S.; van Marle, J.; Tytgat, G.N.J.; Huibregtse, K. Published in:Gastrointestinal endoscopy Link to publicationCitation for published version (APA): Smits, M. E., Groen, A. K., Mok, K. S., van Marle, J., Tytgat, G. N. J., & Huibregtse, K. (1997). Analysis of occluded pancreatic stents and juices in patients with chronic pancreatitis. Gastrointestinal endoscopy, 45, 52-58. General rightsIt is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other than for strictly personal, individual use, unless the work is under an open content license (like Creative Commons). Disclaimer/Complaints regulationsIf you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library: http://uba.uva.nl/en/contact, or a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible. Background: Pancreatic stents may occlude with time, and there is little information available on the nature of the clogging process. Methods: We analyzed the contents of occluded pancreatic polyethylene stents in nine patients with chronic pancreatitis. In the same patients, the protein patterns in the corresponding pancreatic juices were analyzed. The stents had been in place for a mean of 9 weeks (range 2 to 17). Results: All stents were occluded at both ends, especially around side holes, with thick creamy-white precipitate. The average dry weight of occluding debris was 3 mg per 3.25 cm 10F stent. Total protein content was 50% (SD 16.3) and total calcium 0.8% of dry weight (SD 0.6). Light microscopy showed that proteinaceous material completely filled the stent lumen. Yeasts and plant material were seen in two stents. A variable number of bacteria of mixed species, sometimes in clumps, were patchily scattered in the protein matrix. Cultures of stent contents grew several species of Gram-positive and negative bacteria. Scanning and transmission electron microscopy showed an amorphous protein matrix in all stents, arranged as a network in some areas, but in layers in other areas. Sodium dodecylsulfate polyacrimide gel electrophoresis showed that protein patterns of stent contents were remarkably different from the protein patterns of the juice samples of the same patient. A 66 kD band, identified as albumin, appeared in the protein patterns of stent content, whereas it was lacking in most juice samples. Conclusions: Adherence of protein, especially albumin, plays an important role in the process of pancreatic stent clogging. Other factors, such as bacteria, refluxed duodenal contents, and calcium seem to be of less importance.

A Novel Approach for Treatment of Unresectable Pancreatic Cancer: Design of Radioactive Stents and Trial Studies on Normal Pigs

“…This idea is supported by the examination of the blocked stents at the end of the experiments, which showed that the stents were blocked by necrotic tissue caused by irradiation and refluxed duodenal contents. Moreover, it has been reported that the mean time for stent occlusion in the treatment of chronic pancreatitis is 9 weeks (25,26), much longer than the occlusion time seen here. This data further support the conclusion that the higher dose of radiation is the main reason for the blockage of the stents.…”

Proteomic Analysis of Protein Plugs: Causative Agent of Symptoms in Patients with Choledochal Cyst

“…The 66-kDa albumin may represent contamination, because albumin is contained in blood, bile, and pancreatic juice, which cannot be removed completely from surgical samples [34][35][36]. However, albumin possesses a good binding capacity for chemically diverse molecules, and is reported to consist of clogging material that occludes pancreatic stents placed in the pancreatic ducts of patients with chronic pancreatitis during endoscopic management [37][38][39]. Albumin seems to be a minor but true component of protein plugs, binding to lithostathines.…”

Pancreatic Stone Protein/Regenerating Protein Family in Pancreatic and Gastrointestinal Diseases

“…Good clinical results, however, are hampered by rapid occlusion. Analysis of protein components of clogging materials in pancreatic stents proved PSP/lithostathine, albumin and trypsin as major protein components (57)(58)(59). Details of the mechanism in pancreatic stent occlusion still remain uncertain, but stents with larger side holes may less frequently become clogged (60).…”