How Many People Have This Disease Right Now？

It has been reported that the prevalence of chronic pancreatitis ranges from 3 to 10 per 100,000 people around the world（Lankisch and Banks 1998）.Lankisch and Banks pointed out that abdominal pain，steatorrhea，and diabetes mellitus are the major problems in treating chronic pancreatitis patients and that chronic pancreatitis must be considered a premalignant disease（Lowenfels et al.1993，1997；Raimondi et al.2010）.If this is true for Western countries（Banks 2002），in Japan，the estimated annual prevalence and incidence of chronic pancreatitis in 2011 were 52.4/100,000 and 14.0/100,000，respectively（Hirota et al.2014）.Finally，the data from other countries are largely unknown and this represents a notable stumbling block for planning adequate health strategies，especially in low-and middle-income countries where economic resources are limited（Mills 2014）.(https://www.daowen.com)

Thereis also a newcomer to the scene of chronic pancreatitis，namely autoimmune pancreatitis（AIP）（Pezzilli and Pagano 2014）and its exact incidence is still unknown（Pezzilli et al.2012）.The only epidemiological data regarding AIP is that，in patients having a Whipple resection for the suspicion of a pancreatic neoplasm，2.5%have AIP（Abraham et al.2003）.