Negotiating the complexities of exocrine and endocrine dysfunction in chronic pancreatitis.

Chronic pancreatitis is a chronic inflammatory disease of the pancreas characterised by irreversible morphological change and typically causing pain and/or permanent loss of function. This progressive, irreversible disease results in destruction of healthy pancreatic tissue and the development of fibrous scar tissue. Gradual loss of exocrine and endocrine function follows, along with clinical manifestations such as steatorrhoea, abdominal pain and diabetes. Nutrition in chronic pancreatitis has been described as a problem area and, until recently, there was little research on the topic. It is often asserted that >90 % of the pancreas must be damaged before exocrine insufficiency occurs; however, an exploration of the original studies from the 1970s found that the data do not support this assertion. The management of steatorrhoea with pancreatic enzyme replacement therapy is the mainstay of nutritional management, and early identification and treatment is a key. The presence of steatorrhoea, coupled with poor dietary intake (due to intractable abdominal pain, gastrointestinal side effects and often alcoholism) renders the chronic pancreatitis patients at considerable risk for undernutrition, muscle depletion and fat-soluble vitamin deficiency. Premature osteoporosis/osteopenia afflicts two-thirds of patients as a consequence of poor dietary intake of calcium and vitamin D, low physical activity, low sunlight exposure, heavy smoking, as well as chronic low-grade inflammation. Bone metabolism studies show increased bone formation as well as bone resorption in chronic pancreatitis, indicating that bone turnover is abnormally high. Loss of the pancreatic islet cells occurs later in the disease process as the endocrine cells are diffusely distributed throughout the pancreatic parenchyma. Patients may develop type 3c (pancreatogenic) diabetes, which is complicated by concurrent decreased glucagon secretion, and hence an increased risk of hypoglycaemia. Diabetes control is further complicated by poor diet, malabsorption and (for some) alcoholism, and therefore those with type 3c diabetes have clinical characteristics and therapeutic goals that are different from that of type 1 and type 2 diabetes patients. This review describes emerging research and clinical guidelines for nutrition in chronic pancreatitis.