Ep 167 – Acute pancreatitis

Acute pancreatitis is an inflammatory condition of the pancreas, most commonly caused by bile stones or excessive use of alcohol. It is one of the most common diseases of the gastrointestinal tract leading to hospital admission. In most patients, the disease takes a mild course, where moderate fluid resuscitation, management of pain and nausea and early oral feeding result in rapid clinical improvement. The severe form is life-threatening, with mortality rates of up to 30%. In this episode, Dr Roger Henderson looks at how to quickly diagnose acute pancreatitis, what the common risk factors are, the treatment options and prognosis.

Key take-home points

• Acute pancreatitis is an inflammatory disorder of the pancreas characterised by autodigestion of pancreatic tissue due to premature activation of pancreatic enzymes.
• The incidence in the UK is 56 cases per 100,000 people per year, with around 50% of cases being caused by gallstones, 25% by alcohol and 25% by other factors.
• Gallstone pancreatitis is more common in women >60 years of age, especially among patients with microlithiasis.
• Alcoholic pancreatitis is seen more frequently in men. It is dose-dependent and more common in people drinking more than 50–80 grams of alcohol daily over several years.
• Idiopathic pancreatitis may and does occur, where no clear aetiology is identified despite extensive evaluation.
• Patients typically present with severe, constant upper abdominal pain, usually sudden in onset and often radiating to the back. There is associated nausea or vomiting in 80% of patients that is sometimes intractable.
• Diagnosis can be confirmed if at least two of the following three criteria are met: upper abdominal pain (epigastric or left upper quadrant), elevated serum lipase or amylase (more than three-times the upper limit of normal) or characteristic findings on abdominal imaging (computed tomography, magnetic resonance cholangiopancreatography, ultrasound).
• Physical findings vary according to the severity of the pancreatitis, ranging from a generally well patient to a seriously ill patient with abnormal vital signs such as tachycardia and fever.
• Because of the anatomical location of the pancreas, any guarding on abdominal palpation in someone with acute pancreatitis may be less intense than expected for the degree of pain the patient is experiencing.
• All patients with acute pancreatitis need a transabdominal ultrasound to confirm or exclude cholelithiasis.
• Most patients do not need contrast-enhanced computed tomography scans because the diagnosis is usually based on clinical presentation and serum lipase/amylase.
• There is no specific pharmacological treatment for acute pancreatitis; management is primarily supportive.
• Routine prophylactic antibiotics are not recommended, even in cases of sterile necrosis.
• Endoscopic retrograde cholangiopancreatography is indicated urgently if acute pancreatitis is associated with cholangitis or persistent biliary obstruction.
• Cholecystectomy should be performed during the same admission for patients with gallstone pancreatitis to prevent recurrence, but in severe gallstone pancreatitis any cholecystectomy is usually delayed for at least 6 weeks, until the local inflammation has resolved.
• The majority of patients with acute pancreatitis have mild disease and improve within 3–7 days of conservative management.
• The overall mortality rate is around 5%, but in severe acute pancreatitis with infected necrosis or persistent organ failure it may reach 30% or more.
• All patients who have had pancreatitis should be strongly encouraged to abstain completely from tobacco and alcohol.

Key references

1. NICE. 2020. https://www.nice.org.uk/guidance/ng104.
2. Leppäniemi A, et al. World J Emerg Surg. 2019;14:27. doi: 10.1186/s13017-019-0247-0.
3. Quinlan JD. Am Fam Physician. 2014;90(9):632-639.
4. Papachristou GI, et al. Am J Gastroenterol. 2010 Feb;105(2):435-441. doi: 10.1038/ajg.2009.622.
5. Hines OJ, Pandol SJ. BMJ. 2019:367;l6227. doi: 10.1136/bmj.l6227.