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Pitfalls and fatal complications after iterative endoscopic retrograde cholangiopancreatography or percutaneous transhepatic cholangiography management of biliary tract cysts. When to do open surgery (cyst resection; hepaticojejunostomy) or liver transplant?

Andrea Cariati, Giuliano Bottino, Pietro Diviacco, Antonella De Negri, Eva Moraglia, Valerio Belgrano, Irene Leale, Elisa Piromalli, Rosario Fornaro, Mauro Nahun, Enzo Andorno..

Abstract
Biliary tract cysts are a group of rare congenital diseases that have been classified by Todani in 8 types. Hepaticojejunostomy has been the preferred intervention for Type I and IV biliary cysts. It has been postulated that, due to the low incidence of cancerization of Types II and III biliary cysts, a less invasive approach could be suggested, namely cyst resection in Type II, and endoscopic sphincterotomy with opening of choledochocele in small (<3 cm) Type III cysts from old patients. Moreover, Caroli disease has been proposed to be treated by percutaneous biliary drainages. The aim of the present study is to propose the therapeutics strategies to follow for the management of biliary tract cysts, in case of failure of percutaneous transhepatic cholangiography (PTC) and endoscopic retrograde cholangiopancreatography (ERCP). From 2008 to May 2014, three patients with congenital biliary tract cysts were followed. Two patients were found to be affected by bilateral liver Caroli disease and another young patient was found to be affected by a Type III biliary cyst (choledochocele). Patients affected by Caroli disease presented cholangitis, jaundice and fever and have been submitted to PTC. PTC, after an initial brief relief of the symptoms, failed in both cases. One of these patients with recurrent post PTC cholangitis was then successfully treated by orthotopic liver transplant. The other patient affected by Caroli disease died after multiple PTC. The young patient affected by choledochocele suffered from pancreatitis and jaundice and was submitted to ERCP. Endoscopic resection of choledochocele was followed by hemorrhagia and a fatal fungal sepsis. Minimally invasive approaches have been widely used in the management of biliary tract cysts. Diffuse bilateral Caroli disease of the liver can be initially managed by percutaneous drainage but if cholangitis recurs, in our opinion, it is useful to consider an open surgery procedure such as orthotopic liver transplant. Type III biliary cyst (choledococele) can be managed by ERCP if patient is old and the cyst is small (<3 cm) but when the cyst is larger than 3 cm, symptomatic, and the patient is young, one approach to take into consideration is open duodenostomy with choledochocele resection and reimplantation of the common bile and of Wirsung ducts into the duodenal mucosa.

Key words: Biliary tract cysts, Caroli disease, choledochocele, endoscopic retrograde cholangiopancreatography, duodenostomy, percutaneous transhepatic cholangiography, orthotopic liver transplant


 
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REFERENCES
1. Babbitt DP. Congenital choledochal cysts: New etiological concept based on anomalous relationships of the common bile duct and pancreatic bulb. Ann Radiol (Paris)1969;12:231-40.
2. Okada A, Hasegawa T, Oguchi Y, Nakamura T. Recent advances in pathophysiology and surgical treatment of congenital dilatation of the bile duct.  Hepatobiliary Pancreat Surg 2002;9:342-51. [DOI via Crossref]    [Pubmed]   
3. Todani T, Watanabe Y, Narusue M, Tabuchi K, Okajima K. Congenital bile duct cysts: Classification, operative procedures, and review of thirty-seven cases including cancer arising from choledochal cyst. Am J Surg 1977;134:263-9. [DOI via Crossref]   
4. Alonso-Lej F, Rever WB Jr, Pessagno DJ. Congenital choledochal cyst, with a report of 2, and an analysis of 94, cases. Int Abstr Surg 1959;108:1-30. [Pubmed]   
5. Singham J, Yoshida EM, Scudamore CH. Choledochal cysts: Part  2 of 3: Diagnosis. Can J Surg 2009;52:506-11. [Pubmed]    [PMC Free Fulltext]   
6. Chen JJ, Lee HC, Yeung CY, Chan WT, Jiang CB, Sheu JC. Meta-analysis: The clinical features of the duodenal duplication cyst. J  Pediatr Surg 2010;45:1598-606. [DOI via Crossref]    [Pubmed]   
7. Venu RP, Geenen JE, Hogan WJ, Dodds WJ, Wilson SW, Stewart ET, et al. Role of endoscopic retrograde cholangiopancreatography in the diagnosis and treatment of choledochocele. Gastroenterology 1984;87:1144-9. [Pubmed]   
8. De Angelis P, Foschia F, Romeo E, Caldaro T, Rea F, di Abriola GF, et al. Role of endoscopic retrograde cholangiopancreatography in diagnosis and management of congenital choledochal cysts: 28 pediatric cases. J Pediatr Surg 2012;47:885-8. [DOI via Crossref]    [Pubmed]   
9. Cariati A, Piromalli E, Morelli N, Bottino G, Andorno E. Indications for Laparoscopic Cholecystectomy or Oral Dissolution Therapy with Ursodeoxycholic Acid in Symptomatic Gallstone Disease. Arch Clin Exp Surg 2014; 3:161-5.
10. Cariati A. Gallstone Classification in Western Countries. Indian J Surg 2015;77(Suppl 2):376-80. [DOI via Crossref]    [Pubmed]   
11. Nicholl M, Pitt HA, Wolf P, Cooney J, Kalayoglu M, Shilyansky J, et al. Choledochal cysts in western adults: Complexities compared to children. J Gastrointest Surg 2004;8:245-52. [DOI via Crossref]    [Pubmed]   
12. Todani T, Tabuchi K, Watanabe Y, Kobayashi T. Carcinoma arising in the wall of congenital bile duct cysts. Cancer 1979;44:1134-41. [DOI via Crossref]   
13. Cariati A, Piromalli E, Cetta F. Gallbladder cancers: Associated conditions, histological types, prognosis, and prevention. Eur J Gastroenterol Hepatol 2014;26:562-9. [DOI via Crossref]    [Pubmed]   
14. Singham J, Yoshida EM, Scudamore CH. Choledochal cysts. Part 3 of 3: Management. Can J Surg 2010;53:51-6. [Pubmed]    [PMC Free Fulltext]   
15. Jablonska B. Biliary cysts: etiology, diagnosis and management. World J Gastroenterol 2012;18: 4801-10. [DOI via Crossref]    [Pubmed]    [PMC Free Fulltext]   
16. Lipsett PA, Pitt HA. Surgical treatment of choledochal cysts. J Hepatobiliary Pancreat Surg 2003; 10:352-9. [DOI via Crossref]    [Pubmed]   
17. Chatila R, Andersen DK, Topazian M. Endoscopic resection of a choledochocele. Gastrointest Endosc 1999;50:578-80. [DOI via Crossref]   
18. Horaguchi J, Fujita N, Kobayashi G, Noda Y, Ito K, Takasawa O. Clinical study of choledochocele: Is it a risk factor for biliary malignancies? J Gastroenterol 2005;40:396-401. [DOI via Crossref]    [Pubmed]   
19. Masetti R, Antinori A, Coppola R, Coco C, Mattana C, Crucitti A, et al. Choledochocele: Changing trends in diagnosis and management. Surg Today 1996;26:281-5. [DOI via Crossref]    [Pubmed]   
20. Ladas SD, Katsogridakis I, Tassios P, Tastemiroglou T, Vrachliotis  T, Raptis SA. Choledochocele, an overlooked diagnosis: Report of 15  cases and review of 56 published reports from 1984 to 1992. Endoscopy 1995;27:233-9. [DOI via Crossref]    [Pubmed]   
21. Søreide K, Søreide JA. Bile duct cyst as precursor to biliary tract cancer. Ann Surg Oncol 2007;14: 1200-11. [DOI via Crossref]    [Pubmed]   
22. Antaki F, Tringali A, Deprez P, Kwan V, Costamagna G, Le Moine O, et al. A case series of symptomatic intraluminal duodenal duplication cysts: Presentation, endoscopic therapy, and long-term outcome (with video). Gastrointest Endosc 2008;67:163-8. [DOI via Crossref]    [Pubmed]   
23. Law R, Topazian M. Diagnosis and treatment of choledochoceles. Clin Gastroenterol Hepatol 2014;12:196-203. [DOI via Crossref]    [Pubmed]   
24. Pitt HA, Venbrux AC, Coleman J, Prescott CA, Johnson MS, Osterman  FA Jr, et al. Intrahepatic stones. The transhepatic team approach. Ann Surg 1994;219:527-35. [DOI via Crossref]    [Pubmed]    [PMC Free Fulltext]   
25. Shi LB, Peng SY, Meng XK, Peng CH, Liu YB, Chen XP, et al. Diagnosis and treatment of congenital choledochal cyst: 20  years' experience in China. World J Gastroenterol 2001;7:732-4. [Pubmed]    [PMC Free Fulltext]   

How to Cite this Article
Pubmed Style

Cariati A, Bottino G, Diviacco P, Negri AD, Moraglia E, Belgrano V, Leale I, Piromalli E, Fornaro R, Nahun M, Andorno. E. Pitfalls and fatal complications after iterative endoscopic retrograde cholangiopancreatography or percutaneous transhepatic cholangiography management of biliary tract cysts. When to do open surgery (cyst resection; hepaticojejunostomy) or liver transplant?. Arch Clin Exp Surg. 2016; 5(2): 128-133. doi:10.5455/aces.20140714024758


Web Style

Cariati A, Bottino G, Diviacco P, Negri AD, Moraglia E, Belgrano V, Leale I, Piromalli E, Fornaro R, Nahun M, Andorno. E. Pitfalls and fatal complications after iterative endoscopic retrograde cholangiopancreatography or percutaneous transhepatic cholangiography management of biliary tract cysts. When to do open surgery (cyst resection; hepaticojejunostomy) or liver transplant?. http://www.ejmaces.com/?mno=162462 [Access: February 25, 2018]. doi:10.5455/aces.20140714024758


AMA (American Medical Association) Style

Cariati A, Bottino G, Diviacco P, Negri AD, Moraglia E, Belgrano V, Leale I, Piromalli E, Fornaro R, Nahun M, Andorno. E. Pitfalls and fatal complications after iterative endoscopic retrograde cholangiopancreatography or percutaneous transhepatic cholangiography management of biliary tract cysts. When to do open surgery (cyst resection; hepaticojejunostomy) or liver transplant?. Arch Clin Exp Surg. 2016; 5(2): 128-133. doi:10.5455/aces.20140714024758



Vancouver/ICMJE Style

Cariati A, Bottino G, Diviacco P, Negri AD, Moraglia E, Belgrano V, Leale I, Piromalli E, Fornaro R, Nahun M, Andorno. E. Pitfalls and fatal complications after iterative endoscopic retrograde cholangiopancreatography or percutaneous transhepatic cholangiography management of biliary tract cysts. When to do open surgery (cyst resection; hepaticojejunostomy) or liver transplant?. Arch Clin Exp Surg. (2016), [cited February 25, 2018]; 5(2): 128-133. doi:10.5455/aces.20140714024758



Harvard Style

Cariati, A., Bottino, G., Diviacco, P., Negri, A. D., Moraglia, E., Belgrano, V., Leale, I., Piromalli, E., Fornaro, R., Nahun, M. & Andorno., E. (2016) Pitfalls and fatal complications after iterative endoscopic retrograde cholangiopancreatography or percutaneous transhepatic cholangiography management of biliary tract cysts. When to do open surgery (cyst resection; hepaticojejunostomy) or liver transplant?. Arch Clin Exp Surg, 5 (2), 128-133. doi:10.5455/aces.20140714024758



Turabian Style

Cariati, Andrea, Giuliano Bottino, Pietro Diviacco, Antonella De Negri, Eva Moraglia, Valerio Belgrano, Irene Leale, Elisa Piromalli, Rosario Fornaro, Mauro Nahun, and Enzo Andorno.. 2016. Pitfalls and fatal complications after iterative endoscopic retrograde cholangiopancreatography or percutaneous transhepatic cholangiography management of biliary tract cysts. When to do open surgery (cyst resection; hepaticojejunostomy) or liver transplant?. Archives of Clinical and Experimental Surgery (ACES), 5 (2), 128-133. doi:10.5455/aces.20140714024758



Chicago Style

Cariati, Andrea, Giuliano Bottino, Pietro Diviacco, Antonella De Negri, Eva Moraglia, Valerio Belgrano, Irene Leale, Elisa Piromalli, Rosario Fornaro, Mauro Nahun, and Enzo Andorno.. "Pitfalls and fatal complications after iterative endoscopic retrograde cholangiopancreatography or percutaneous transhepatic cholangiography management of biliary tract cysts. When to do open surgery (cyst resection; hepaticojejunostomy) or liver transplant?." Archives of Clinical and Experimental Surgery (ACES) 5 (2016), 128-133. doi:10.5455/aces.20140714024758



MLA (The Modern Language Association) Style

Cariati, Andrea, Giuliano Bottino, Pietro Diviacco, Antonella De Negri, Eva Moraglia, Valerio Belgrano, Irene Leale, Elisa Piromalli, Rosario Fornaro, Mauro Nahun, and Enzo Andorno.. "Pitfalls and fatal complications after iterative endoscopic retrograde cholangiopancreatography or percutaneous transhepatic cholangiography management of biliary tract cysts. When to do open surgery (cyst resection; hepaticojejunostomy) or liver transplant?." Archives of Clinical and Experimental Surgery (ACES) 5.2 (2016), 128-133. Print. doi:10.5455/aces.20140714024758



APA (American Psychological Association) Style

Cariati, A., Bottino, G., Diviacco, P., Negri, A. D., Moraglia, E., Belgrano, V., Leale, I., Piromalli, E., Fornaro, R., Nahun, M. & Andorno., E. (2016) Pitfalls and fatal complications after iterative endoscopic retrograde cholangiopancreatography or percutaneous transhepatic cholangiography management of biliary tract cysts. When to do open surgery (cyst resection; hepaticojejunostomy) or liver transplant?. Archives of Clinical and Experimental Surgery (ACES), 5 (2), 128-133. doi:10.5455/aces.20140714024758





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