Pancreatitis

Acute pancreatitis

Demographics: alcoholism (35%) or gallstone disease (40–50%) are the two leading causes.

Murtagh’s triad: severe pain + nausea and vomiting + a relative lack of abdominal signs suggests acute pancreatitis.

History: sudden-onset epigastric pain that may radiate to the back, sometimes relieved by sitting forward; loss of appetite; nausea and vomiting; may be preceded by an alcohol binge or a fatty meal; sweating or weakness; recent ERCP; new medication (e.g. azathioprine, antiretrovirals, chemotherapeutic drugs). Other, less common causes: viral infection, severe hypertriglyceridaemia (≥5.6mmol/L — distinct from the mild-moderate 1.7–5.6mmol/L range, which is a cardiovascular-risk rather than pancreatitis-risk target), hypercalcaemia, trauma, genetic mutation or congenital abnormalities, vasculitis, and cancer.

Examination: the patient is weak, pale, sweating, and anxious. Check vital signs (fever, tachycardia ± shock). Tender in the epigastrium, but typically without guarding, rigidity, or rebound. Reduced bowel sounds (may be absent if ileus); ± abdominal distension.

Investigations: serum lipase (usually at least 3× the reference range); FBC (leucocytosis); CRP (elevated); serum glucose (elevated); serum calcium (decreased); LFTs (may show an obstructive pattern). Ultrasound first; if no cause is identified on history/imaging, or it’s a second/recurrent episode with a previously normal ultrasound, use CT (or MRCP if contrast allergy or renal insufficiency).

Management: admit to hospital, ED assessment if high clinical suspicion. Nil by mouth; IV hydration (early aggressive IV hydration is most beneficial in the first 12–24 hours); monitor urine output; analgesia (IV morphine or fentanyl); antiemetics as required. ERCP is indicated in gallstone pancreatitis where there is cholangitis, jaundice, or a dilated common bile duct.

Chronic pancreatitis

Demographics: chronic alcohol consumption is the main cause.

History: epigastric pain radiating through to the back; symptoms may relapse and worsen over time; weight loss from malabsorption; steatorrhoea.

Examination: there may be very few clinical signs.

Investigations: abdominal X-ray or CT can show pancreatic calcification. MRCP is the most sensitive imaging study — may show stones, pseudocysts, other structural abnormalities, or malignancy. Faecal elastase (normal >200µg/g; pancreatic exocrine insufficiency <200µg/g).

Management: the patient must stop drinking — often enough alone to control the pain. Simple analgesia (avoid opioids), lifestyle modification, and referral to a pain clinic. Pancreatic enzyme supplements may be needed for pancreatic exocrine insufficiency — titrate the dose to symptoms (e.g. loose, foul-smelling bowel movements, weight loss); normal starting dose is 40,000 units of lipase with each main meal; refer to a specialist dietitian or specialist for advice; may need fat-soluble vitamin supplementation (especially vitamin D).

Note: the pain of pancreatic cancer is indistinguishable from chronic pancreatitis, but tends to be more severe and more prominent in the back. Beware of abdominal pain plus weight loss — investigate for pancreatic cancer.