<prompt> Answer this question truthfullyWhere do gallstones need to reach in order to cause both cholangitis and pancreatitis by blocking both the common bile and pancreatic ducts?  <response>: <reason> Gallstones need to reach the confluence of the common bile and pancreatic ducts at the ampulla of Vater to block both ducts double duct sign causing cholangitis and pancreatitis. 