1.5 Symptoms
1.5.1 Abdominal Pain
The most common symptom of CP is abdominal pain，found in 60～100%of the patients and most of the pain is located in the left and upper abdomen.The pain could radiates to the back，with different frequency and duration of episodes.During the remission，patients may feel continuously uncomfortable and even faint pain.Episodic pain is a definite symptom of CP and it is classically described as constant pain in the epigastric area with radiation to the back（Pitchumoni 1998）.Painful episodes last roughly a week and are often accompanied by fatigue，nausea，vomiting，food avoidance，and weight loss（Braganza et al.2011）.It has been estimated that overall 5-10%of patients with CP，especially those with late-onset idiopathic diseases，do not suffer from abdominal pain（Pitchumoni 1998）.In the beginning of the disease，the interval of abdominal pain is relatively long，then it becomes shorter as the pain occurs more frequent with longer duration each time，indicating exacerbation of the symptom.Pain patterns（Table 7.1）are originally scored into one of five patterns based on the American Gastrointestinal Association's technical review（Warshaw et al.1998）.
CP is mostly found in mid-aged men，induced by intemperate drinking and meal.Pain is typically worsened with food intake and may be ameliorated without some kinds of precipitating food.Pain can be alleviated when patients sit orbend their knees and the position is called“Pancreas Position”，but exacerbating pain would occur when patients lie down.Doctors from Changhai Hospital reported 42 cases of CP children，with the average age of 11.7 years old.The figures also demonstrate that upper abdominal pain accounted for 78.5%（Wang et al.2009a）.The severity of the pain is mostly grouped into light and serious rather than using pain scores.The mechanism of abdominal pain has not been clear so far.It may result from increasing inner pressure of pancreatic ducts and pancreatic parenchyma caused by pancreatic duct obstruction，nerve stimulation by inflammatory products in the pancreatic tissue，nerve inflammatory cell infiltration around pancreas，increasing sensitivity of spinal cord and central nervous system with pain（Braganza et al.2011；Navaneethan and Venkataraman 2010；Ceyhan et al.2007；Vardanyan and Rilo 2010；Drenes et al.2008）.
Table 7.1 Pain patterns based on the American Gastrointestinal Association's technical review（Warshaw et al.1998）
1.5.2 Pancreatic Exocrine Insufficiency
More than 90%of pancreatic exocrine function loss will cause significant exocrine insufficiency（Affronti 2011）.The main symptoms are anorexia，upper abdomen fullness and distension after meal，intolerant with greasy food，weight loss etc.Due to lipase and protease secretion decrease，food cannot be fully digested and absorbed leading to steatorrhea（Dimagno and Dimagno 2011）patients’daily stool frequency varies from 3 to 30，with the excreta presenting light color，large quantity，foam and cacosmia.Microscopic examination can find lipid droplets and muscle fibers.Due to poor fat absorption，the patients may appear fat-soluble vitamin deficiency symptoms，such as night blindness，rough skin，bleeding tendency etc（Pezzilli 2009）.Typical steatorrhea is showed in Fig.7.1.(https://www.daowen.com)
Fig.7.1 Typical steatorrhea
1.5.3 Pancreatic Endocrine Insufficiency
About 1/3 of patients have dominant diabetes，other 1/3 glucose metabolism disorder just showing glucose tolerance abnormal（Singer et al.1985）.Contrary to primary diabetes，diabetes resulting from CP rarely cause retinopathy，nephropathy，atherosclerosis and ketoacidosis.This may be due to the locality，non-uniformity，and slow progression of pancreatic parenchymal damage caused by CP.