- Chronic pancreatitis is a chronic inflammatory disease characterised by fibrosis and destruction of exocrine pancreatic tissue.
- Diabetes mellitus occurs in advanced cases because the islets of Langerhans are involved.
Pathophysiology
- Around 80% of cases in Western countries result from alcohol misuse
- In developing countries malnutrition and associated dietary factors have been implicated.
Other causes
- Cystic Fibrosis
- Benign and malignant processes obstructing pancreatic duct
- Congenital anomaly like pancreatic divisum
- Rarely, inherited as autosomal dominant with variable penetrance
Clinical features
- Chronic pancreatitis predominantly affects middle-aged alcoholic men
- Pain is the most common presentation of chronic pancreatitis and is usually epigastric and often radiating through into the back.
- In 50%,episodes of 'acute pancreatitis‘ with each attack resulting in a degree of permanent pancreatic damage.
- In 35%, relentless, slowly progressive chronic pain without acute exacerbations
- remainder have no pain but diarrhoea
- Exocrine and endocrine insufficiency may develop at any time, and occasionally malabsorption or diabetes are the presenting features in the absence of abdominal pain.
- Steatorrhoea
- Protein malabsorption
- Diabetes Mellitus
- Weight loss is common and results from a combination of anorexia, avoidance of food because of post-prandial pain, malabsorption and/or diabetes
Complications
Pseudocyst - < 6cm, usually resolves spontaneously; > 6cm, requires intervention
Ascites
Pleural effusion
Strictures – CBD, duodenum
Portal hypertention
Investigations
The extent dependens upon the clinical setting.
In a patient with known alcohol abuse and typical pain few confirmatory tests are required.
Tests performed include:
- Faecal elastase level will be abnormal in the majority
- Serum amylase and lipase levels are rarely significantly elevated in established chronic pancreatitis
- Pancreolauryl test
- Transabdominal ultrasound scan is used for initial assessment.
- Contrast-enhanced spiral CT scan – test of choice
- MRCP
- Endoscopic ultrasound – specifically for assessing complications
- Diagnostic ERCP – replaced by MRCP in developed countries
CT scan showing a grossly dilated and irregular duct with a calcified stone (arrow A). Note the calcification in the head of the gland (arrow B).
MRCP of the same patient showing marked ductal dilatation with abnormal dilated side branches (arrows A). A small cyst is also present (arrow B).
Endoscopic retrograde cholangiogram shows grossly dilated pancreatic ducts (arrows) in a patient with long-standing pancreatitis
Treatment
- Alcohol avoidance is crucial in halting the progression of the disease and reducing pain.
Pain relief
- Analgesics particularly NSAIDs are useful
- Opiates reserved for chronic unremitting pain and often leads to addiction
- Oral pancreatic enzyme supplementation reduces pancreatic secretion of enzymes and thus provides pain relief in some patients.
- Coeliac plexus neurolysis or minimally invasive thoracoscopic splanchnicectomy – provides long term pain relief but pain eventually recurs
Patients who are abstinent from alcohol and who have severe chronic pain which is resistant to conservative measures are considered for intervention with following procedures:
- Endoscopic therapy
Dilatation or stenting of pancreatic duct strictures
Removal of calculi (mechanical or shock-wave lithotripsy)
Surgical methods
Partial pancreatic resection, preserving the duodenum
Pancreatico-jejunostomy
Total pancreatectomy – high morbidity and mortality with the procedure
- Steatorrhoea - dietary fat restriction , oral pancreatic enzyme supplements; a proton pump inhibitor is added to optimise duodenal pH for pancreatic enzyme activity
- Management of complications
