Acute pancreatitis (GI) Flashcards
Define acute pancreatitis.
Autodigestion of pancreatic tissue by the pancreatic enzymes, leading to necrosis
What are the causes of acute pancreatitis?
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- Idiopathic (10-20%)
- Gallstones (F>M)
- Ethanol (most common worldwide, M>F)
- Trauma
- Steroids
- Mumps
- Autoimmune disease e.g. collagen vascular diseases / Ascaris infection
- Scorpion venom
- Hypertriglyceridaemia, hypercalcaemia, hyperchylomicronaemia, hypothermia
- ERCP
- Drugs (mesalazine, azathioprine, sodium valproate, furosemide, bendroflumethiazide, pentamidine, didanosine)
What drugs can cause acute pancreatitis? (7)
- mesalazine
- azathioprine
- sodium valproate
- furosemide
- bendroflumethiazide
- pentamidine
- didanosine
How can acute pancreatitis be classified? (3)
- mild (80%) - no organ failure, no complications
- moderate - no/transient (<48h) organ failure, possible complications
- severe - persistent (>48h) organ failure, possible complications
Describe the pathophysiology of acute pancreatitis.
- local inflammation of pancreas –> enzyme release –> autodigestion
- abnormal intracellular calcium accumulation –> potentiate colocalization of zymogen and lysosome granules –> premature enzymatic activation
- proteases and inflammatory response can cause leaks in blood vessels and rupture –> excess fluid and pancreatic swelling and bleeding
- activated lipases can destroy peripancreatic fat
- digestion and bleeding can liquify tissue –> liquefactive haemorrhagic necrosis
- ethanol: direct toxic insult to acinar cell –> inflammation and membrane destruction
- causes increase in ductal Pa secondary to protein deposition within the pancreatic duct favouring retrograde flow and intra-pancreatic enzymatic activation
- sphincter of Oddi dysfunction
What is the most likely cause of chronic pancreatitis?
Alcohol
What are the clinical features of acute pancreatitis? (7)
- epigastric pain radiating to the back - constant, severe, sudden, worse with movement
- tender, distended abdomen with voluntary guarding
- nausea and vomiting –> dehydration, electrolyte abnormalities, hypokalaemic metabolic alkalosis
- signs of shock - hypovolaemia (dry mucous membranes, decreased skin turgor, sweating), hypotension, tachycardia
- anorexia
- fever
- signs of pleural effusion - ARDS, reduced air entry, stony dullness on percussion
What can nausea and vomiting in acute pancreatitis lead to? (3)
- dehydration
- electrolyte abnormalities
- hypokalaemic metabolic alkalosis
What signs of shock are seen in acute pancreatitis? (3)
- hypovolaemia - dry mucous membranes, decreased skin turgor, sweating
- hypotension
- tachycardia
What signs of pleural effusion might be seen in acute pancreatitis? (3)
- ARDS
- reduced air entry
- stony dullness on percussion (more commonly on left)
What do we see in severe pancreatitis? (2)
- Cullen’s sign: periumbilical bruising
- Grey-Turner sign: bruising of flanks
What might you see on examination of acute pancreatitis? (5)
- signs of hypovolaemia - oliguria, hypotension, dry mucous membranes, decreased skin turgor, sweating, tachycardia, tachypnoea
- signs of pleural effusion - ARDS, reduced air entry, stony dullness on percussion
- jaundice (severe gallstone pancreatitis)
- signs of hypercalcaemia (Chvostek’s or Trousseau’s sign)
- ecchymotic bruising and discolouration (Cullen’s, Grey Turner’s, Fox’s sign) if haemorrhagic
What are the risk factors for acute pancreatitis?
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- gallstones
- alcohol (F 50-70 or young/middle-aged men)
- trauma
- steroids
- mumps
- autoimmune conditions (SLE, Sjogren’s)
- scorpion venom
- hypertriglyceridaemia and hypercalcaemia
- ERCP (use of contrast –> pancreatic inflammation)
- drugs
What are the main factors indicating severe pancreatitis? (6)
- age >55
- hypocalcaemia (<2mmol/L)
- hyperglycaemia (>10mmol)
- hypoxia (<7.9kPa)
- neutrophilia
- elevated LDH and AST
What criteria is used to determine severity of pancreatitis?
Glasgow score: 3+ means severe pancreatitis
What is the Glasgow score for severity of pancreatitis?
PANCREAS: 3+ –> severe pancreatitis
- PaO2 <7.9kPa
- Age >55
- Neutrophilia
- Calcium <2mmol/L
- Renal function: urea >16mmol/L
- Enzymes –> elevated LDH & AST
- Albumin <32g/L
- Sugar: glucose >10mmol
What are the first-line investigations for acute pancreatitis? (4)
- serum lipase or amylase
- FBC with differential
- CRP
- urea/creatinine
What are serum amylase/lipase like in acute pancreatitis?
Serum lipase or amylase >3x upper limit of normal (in 1000s) - confirms the diagnosis of acute pancreatitis in a patient with acute upper abdominal pain
Which out of serum amylase and lipase is more useful?
Serum lipase:
- lipase levels remain elevated for longer (14d vs 5d for amylase) –> better for diagnosis in delayed presentation
- more sensitive and specific than amylase
What does FBC show in acute pancreatitis? (3)
- leukocytosis with left shift (more immature neutrophils)
- neutrophilia
- elevated haematocrit is predictor of poor prognosis due to increased risk of necrotising pancreatitis
What does urea/creatinine show in acute pancreatitis?
Elevated - suggests dehydration or hypovolaemia
What might LFTs show in acute pancreatitis?
Elevated LFTs suggest gallstones are the cause
What might serum calcium show in acute pancreatitis?
- high
- causative
- whilst hypercalcaemia can cause pancreatitis, hypocalcaemia is an indicator of pancreatitis severity
What imaging is done in acute pancreatitis and why? (4)
- early abdominal US to assess aetiology as this affects management
- contrast-enhanced CT (CECT) - investigating differentials, may also show pseudocyst, inflammation, necrosis
- erect CXR - rule out perforation, may show pleural effusion or elevated hemidiaphragm, atelectasis
- ERCP/MRCP - if gallstones suspected