Worst outcomes if missed
Death – failure of the pulmonary, cardiovascular and renal systems is a feature of severe pancreatitis, and multiple organ failure has a high risk of death.
Epidemiology
The incidence in the UK varies between 150 and 420 cases per million per year. Acute pancreatitis is one of the most common surgical emergencies – a large hospital will see two to three cases each week. These numbers translate into approximately one case every one to two years for a general practice list of 2000.
Symptoms and signs
A typical presentation of acute pancreatitis is sudden, severe epigastric pain, often the worst the patient has ever experienced. About half of patients experience radiation to the back and about 80% of patients will have at least one episode of vomiting before admission to hospital. Abdominal examination shows tenderness with guarding in the upper abdomen.Occasionally the pain may be of a more gradual onset and less severe. Patients with gallstones and those with a high alcohol intake are at risk of acute pancreatitis, so abdominal pain in such patients should be assessed carefully.
Differential diagnosis
• Perforated peptic ulcer.
• Acute cholecystitis.
• Biliary colic.
• Ischaemic bowel.
• Ruptured aortic aneurysm.
• Myocardial infarction.
Some patients with less severe symptoms may be considered to have gastritis. However, the patient with gastritis usually presents with vague recurrent upper abdominal pain or discomfort, whereas in pancreatitis there is severe persistent pain of recent onset.
Investigation and referral
If a patient presents in surgery with a history of three to four days of abdominal pain, which may be settling, urgent admission might not be required. If there is adequate oral intake of fluid and analgesia can be achieved, it may be reasonable to perform blood tests (white count and CRPand arrange an urgent ultrasound to look for gallstones if this can be obtained within a few days.
If stones are present, refer the patient for urgent outpatient assessment with a view to early cholecystectomy. If the patient presents within two to three days of onset of symptoms, plasma amylase or lipase may be helpful. However, this situation is rare, and when symptoms have been present for three to four days, enzyme levels are returning to normal.
Five key questions
- In an adult with sudden onset epigastric pain, radiating to the back, with vomiting, could this be acute pancreatitis? – Yes. The patient may have only pain, without radiation or vomiting.
- If a patient has symptoms suggestive of acute pancreatitis, how much alcohol do they drink? What medications are they taking? – High alcohol intake and a range of medications are associated with pancreatitis.
- In a patient known to have gallstones, could sudden onset of abdominal pain be due to pancreatitis? – Sudden onset and unremitting pain in the central epigastrium is likely to be acute pancreatitis.
- A previously well person presents with a three-to-four-day history of severe epigastric pain. Is pancreatitis a high possibility? Yes. Features include vomiting at pain onset and persistence of pain.
- After admission for severe pancreatitis, are there signs of malabsorption or exocrine insufficiency? – Some 80% of patients have exocrine insufficiency, and 40% become diabetic.
How not to miss problems during recovery
Whereas diagnosis and treatment of acute pancreatitis are usually hospital based, the recovery phase will require input from the GP. Patients with mild pancreatitis recover spontaneously, but it is important to ensure that the cause, if known, has been eradicated (for instance by cholecystectomy, alcohol cessation, avoiding potential causative medication). Patients with severe pancreatitis who have been in hospital are very likely to have pancreatic exocrine insufficiency. Their recovery will be delayed by malabsorption and appropriate treatment can speed up this process.
Five red herrings
Raised amylase without symptoms – macroamylasaemia is a genetically determined condition in which amylase molecules tend to polymerise. This creates much larger molecules that are not removed by the kidneys, but which are functionally normal. The result is high levels of amylase activity in the blood, in the absence of pancreatic abnormality. A low ratio of urinary to plasma amylase is diagnostic.
Epigastric pain, repeated episodes lasting a few hours – these symptoms are unlikely to be due to pancreatitis (either acute or chronic), in which the pain is persistent, and usually so severe that the patient seeks immediate medical attention. Short-lived episodes of epigastric pain may be due to duodenal ulceration, or biliary colic. Investigation by upper GI endoscopy or biliary ultrasound might be appropriate.
Regular alcohol consumption must be the cause – many patients consume alcohol but few develop pancreatitis. Other causes (gallstones, medication, viral infection) must be investigated by ultrasound and careful history before alcohol is accepted as the cause.
Patient drinks moderately, or infrequently, so alcohol cannot be the cause – the susceptibility to injury by alcohol is very variable. There is no safe threshold. Pancreatic toxicity may be affected by the pattern of drinking, or combination with dietary content. There is evidence that during recovery from acute pancreatitis the risk of further attacks is greater in those who continue to consume alcohol, so expert consensus is that all patientsshould be advised to abstain for at least six months after acute pancreatitis.
Symptoms have resolved, so there is no urgency to investigate or treat – it is essential to discover the cause, and eliminate it as quickly as possible, to avoid a further attack of acute pancreatitis which could lead to permanent impairment of pancreatic function, or even death. As a minimum, ultrasound examination is performed in hospital – if found, definitive treatment is required, ideally before discharge from hospital, and at the latest within two weeks of discharge. In the absence of stones or alcohol, other causes must be investigated by careful history, and appropriate changes made to treatment if necessary.
Diagnosis of exocrine insufficiency
A stool sample can be tested for faecal elastase. Very low levels indicate the need for pancreatic enzymes. If the patient is eating reasonably well, failure to gain weight or a frequent passage of stool suggests exocrine insufficiency. A therapeutic trial of pancreatic enzyme supplements may be justified.
These potentially difficult patients will probably remain under follow-up from the hospital, and if exocrine insufficiency is considered, should be managed jointly with the appropriate specialist.
Mr Colin Johnson is a reader and consultant surgeon at the University Hospital Southampton. He is also president of the European Pancreatic Club 2014 and past president of the Pancreatic Society of Great Britain and Ireland.
Mr Johnson coordinated the writing of The UK Guidelines for the Management of Acute Pancreatitis (2005) and is now chair of the UK and Ireland Pancreatic Guideline Development Group
Further reading
