GI: Pancreatitis, Cholangitis & Peptic Ulcer Disease Flashcards
What is acute pancreatitis?
Inflammation of the pancreas causing extra-ductal release of pancreatic enzymes.
What are the 3 most common causes of acute pancreatitis in the UK?
1) obstructive gallstone disease
2) alcohol excess
3) post-ERCP
Mneumonic for causes of pancreatitis: GET SMASHED
G - Gallstones
E - Ethanol
T - Trauma
S - Steroids
M - Mumps (other viruses include Coxsackie B)
A - Autoimmune (e.g. polyarteritis nodosa), Ascaris infection
S - Scorpion venom
H - Hypertriglyceridaemia, Hyperchylomicronaemia, Hypercalcaemia, Hypothermia
E - ERCP
D - Drugs
What drugs can cause acute pancreatitis?
Azathioprine, mesalazine, bendroflumethiazide, furosemide, steroids, sodium valproate.
Pathophysiology of acute pancreatitis?
1) A triggering event results in an inflammatory response within the pancreatic parenchyma
2) Release of pancreatic enzymes outside of the ductal system
3) Activation of lipase and peptidases outside of the GI tract.
4) Local tissue damage and a worsening inflammatory response.
Give some acute local complications of acute pancreatitis
1) Extra-ductal release of protease enzymes results in soft tissue and vascular damage causing retroperitoneal haemorrhage.
2) The retroperitoneal inflammation results in a reactive ascites.
3) In severe pancreatitis there is a risk of portal venous thrombosis.
Give some late local complications of acute pancreatitis
1) Protease activity within the pancreatic tissue can cause areas of necrosis to develop (this can become infected)
2) Fluid secretion from inflamed and necrotic tissues can become encapsulated within the lesser sac of the peritoneum and form a pancreatic pseudocyst.
Give some systemic complications of acute pancreatitis
1) Release of inflammatory cytokines causes a systemic inflammatory response with systemic vasodilation resulting in cardiovascular shock.
2) There can be an inflammatory reaction in the lungs resulting in interstitial oedema and poor oxygen transfer (acute respiratory distress syndrome).
3) Reactive inflammation of the pleura can result in a pleural effusion (10-20%)
4) Severe pancreatitis can result in a systemic inflammatory response that results in disseminated intravascular coagulation (DIC).
Give some complications of acute pancreatitis?
1) Retroperitoneal haemorrhage (can result in reactive ascites)
2) Risk of portal venous thrombosis
3) Necrosis (can become infected)
4) Pancreatic pseudocyst
5) CVS shock
6) Acute respiratory distress syndrome
7) Pleural effusion
8) Disseminated intravascular coagulation (DIC)
9) Hyperglycaemia
10) Hypocalcaemia
11) Malnutrition
How can acute pancreatitis result in hyperglycaemia?
Due to local damage to islet cells resulting in failure of glucose homeostasis (may persist long-term if pancreatic damage is severe enough).
How can acute pancreatitis result in hypocalcaemia?
Systematic release of lipase causes fat store lysis and release of free fatty acids –> subsequently sequestrates calcium in the blood
How can acute pancreatitis lead to malnutrition?
Loss of exocrine pancreatic tissue results in an acute failure to digest food and malabsorption can develop.
Clinical features of acute pancreatitis?
1) Abdo pain & tenderness:
- severe epigastric pain
- radiates to back
- sudden onset and severe (reaches peak within hours and persists for days)
2) N&V
3) Jaundice
- in cases of gallstone obstruction of ducts
4) Systemically unwell e.g. low grade fever, tachycardia
5) May be features of the cause:
- alcohol use
- weight loss (may indicate pancreatitic or biliary tumour)
- use of drugs e.g. steroids (recent COPD exacerbation)
- history of trauma or recent surgery
- history of ERCP
- history of recent mumps infection
Where does acute pancreatitis abdo pain typically radiate to?
to the back
Location of acute pancreatitis abdo pain?
epigastric
Examination features in acute pancreatits?
Systemic:
- shock (if CVS compromise)
- tachypnoea
- fever
Abdo:
- tenderness in epigatrium with guarding
- distension (due to ascites)
- loss of bowel sounds (due to acute ileus)
- Grey-Turner’s sign
- Cullen’s sign
Respiratory:
- Acute respiratory compromise
- Severe acute respiratory distress syndrome (ARDS).
- Pleural effusion
What is Grey-Turner’s sign?
Bruising of the flanks due to bleeding in the fascial planes (haemorrhagic pancreatitis) from release of protease enzymes in pancreatitis.
RARE
What is Cullen’s sign?
Peri-umbilical bruising in pancreatitis
RARE
What is the diagnostic test for anyone with suspected acute pancreatitis?
1) Serum amylase (this is a pancreatic enzyme): most often used
2) Serum lipase; higher sensitivity and specificity (but not all centres have access)
What are some causes of a raised serum amylase?
1) Acute pancreatitis
2) Upper GI perforation
3) Mesenteric or bowel ischaemia
4) Renal failure
5) Retroperitoneal haematoma
6) Intra-abdominal ectopic pregnancy
7) Inflammation or obstruction of the salivary glands
If serum amylase or lipase levels are inconclusive and there is a high suspicion of acute pancreatitis, what is the most sensitive test?
CT imaging of the abdomen with contrast.
Following diagnosis of acute pancreatitis, why should further investigations be carried out?
1) severity prognostication
2) ascertaining the cause of the acute pancreatitis
What 2 scores can be used to calculate severity in acute pancreatitis?
1) Ranson score
2) Glasgow score
What are some furher investigations that can be done to ascertain the severity of the acute pancreatitis?
1) FBC:
- for WCC (severity of inflammation)
- low Hb carries worse prognosis
2) CRP
3) serum glucose >10 mmol/L
4) U&ES:
- may indicate AKI
- may indicate significant electrolyte disturbances which need treatment with IV fluids
- rising urea
5) LFTs:
- severe pancreatitis can result in liver failure: raised AST & ALT levels
- low albumin
6) Calcium levels
7) LDH
8) ABC:
- low PaO2 < 8 kPa indicates respiratory failure (type 1) due to inflammatory response
- metabolic acidosis due to significant inflammatory response and cardiovascular shock