What is Chronic Pancreatitis?
Chronic Pancreatitis (CP) is a condition characterized by irreversible damage to pancreatic structure or function. It occurs when a severe, repeated or prolonged insult leads to permanent alterations in Pancreatic gland.
How is Chronic Pancreatitis different from Acute Pancreatitis?
The essential difference in CP and AP is the rapidity of disease onset and presentation. Onset of AP can be clearly identified as a discrete event while; in CP there is a continuous ongoing disease activity and hence clinical events cannot be clearly earmarked.
AP usually presents in a stormy fashion with sudden deterioration in patients’ condition but resolves over a period of time unless very severe. On the other hand, CP is characterized by a prolonged discomfort which rarely resolves completely. AP is associated with higher mortality (death rates) than CP; while morbidity (complications impairing the overall quality of life) are higher in CP compared to AP. (Table 1)
Patients with CP usually require frequent visits to the healthcare provider with multiple interventions due to longstanding disease. Risk of development of Pancreatic Cancer also warrants close monitoring in these patients.
Table 1: Differences between Chronic Pancreatitis and Acute Pancreatitis
| Chronic Pancreatitis | Acute Pancreatitis | |
| Etiology | Longstanding or recurrent insult. Rarely severe one-time insult | Severe one-time insult |
| Clinical symptoms | Pain most common and usually the only presenting symptom | Pain most common but usually associated with other symptoms like vomiting, abdominal distension, obstipation, breathlessness, decreased urine output etc. |
| Reversibility | Majority of cases resolve completely | Permanent changes in Pancreatic form/function |
| Morbidity | High | Less in mild AP
Present in moderately severe and severe AP |
| Mortality | Low | High in severe AP |
| Risk of Pancreatic Cancer | Present | Absent |
What are the causes of Chronic Pancreatitis?
The most common cause of Chronic Pancreatitis in excessive Alcohol intake. Nearly half of all patients with CP have history of excessive alcohol intake.
A unique form of CP called Tropical Pancreatitis is seen in southern parts of India and other tropical regions.
It is characterized by CP in young people and presents with recurrent severe abdominal pain and severe malnutrition. Other causes of CP are mentioned in table 2.
Table 2 : Causes of Chronic Pancreatitis
| Chronic Pancreatitis |
| Alcohol |
| Tobacco |
| Genetic Causes |
| Familial |
| Recurrent/Severe Acute Pancreatitis |
| Idiopathic |
| Tropical Pancreatitis |
| Autoimmune Pancreatitis |
What are the symptoms of Chronic Pancreatitis?
The most common symptom of CP is abdominal pain. Pain is troublesome and frequently described as boring, deep and penetrating with radiation to the back. It affects the quality of life; often leading to decreased appetite and severe malnutrition. Most patients find symptom relief only to narcotic analgesics and are thus prone to addiction to these drugs.
The symptoms vary also according to the exocrine or endocrine component being affected. Diarrhea and steatorrhea (fatty stools) are the manifestations when exocrine part is affected while Diabetes is the chief manifestation when endocrine component of Pancreas is affected.
Why is Diabetes so common in Chronic Pancreatitis?
Beta Cells in the Islets of Langerhans present in Pancreas is responsible for the release of Insulin. Glucagon is another major hormone released by Alpha cells in Islets of Langerhans in Pancreas. Both Insulin and Glucagon closely control blood sugar levels in humans.
Because the Pancreas is so intricately associated with glucose homeostasis, any major insult to the Pancreas results in Diabetes. Pancreatic insufficiency occurring with chronic Pancreatitis leads to constellation of symptoms termed Type 3 or “Pancreatic Diabetes” where there is rapid fluctuation of blood sugar levels. This occurs due to the involvement of both glucogenic (Glucagon releasing alpha cells) and anti glucogenic (Insulin releasing beta cells) apparatus of the Islets of Langerhans.
How is Chronic Pancreatitis diagnosed?
In clinical practice, CP is diagnosed with the help of imaging tests like Computed Tomography (CT scan), Magnetic Resonance Imaging of whole abdomen or Cholangio Pancreatography (MRI abdomen or MRCP) or specialized ultrasound technique called endoscopic ultrasound (EUS). Typical imaging findings in CP include atrophy (shrinkage) of Pancreas, dilatation of the pancreatic duct, presence of stones and calcification in the pancreatic duct and in tissue of the Pancreas (Image 1). Details of diagnostic techniques are discussed later.
Image 1: MRCP showing CP with dilated pancreatic duct filled with multiple small stones
Image credit: Busireddy KK, AlObaidy M, Ramalho M, Kalubowila J, Baodong L, Santagostino I, Semelka RC. Pancreatitis-imaging approach. World J Gastrointest Pathophysiol 2014; 5(3): 252-270