Acute & Chronic Pancreatitis Flashcards
What is pancreatitis?
What are the 2 different types?
a condition involving inflammation of the pancreas
pancreatitis can be acute or chronic
acute pancreatitis can return to normal after resolution of the episode
chronic pancreatitis involves continuing inflammation, often with irreversible structural changes
What 2 factors account for the vast majority of cases of acute pancreatitis?
gallstones and alcohol
How does the severity of acute pancreatitis vary?
What is the mortality in the more severe form and why?
severity varies from mild self-limiting to extremely severe with extensive pancreatic and peripancreatic necrosis as well as haemorrhage
mortality is 40-50% in the more severe form as damage can result in the release of lytic enzymes into the blood
this contributes to severe shock and digestion of surrounding tissue
What does the acronym GET SMASHED stand for?
GET SMASHED are the causes of acute pancreatitis
G - gallstones
E - ethanol (alcohol)
T - trauma
S - steroids
M - mumps
A - autoimmune (e.g. SLE)
S - scorpion bites
H - hypercalcaemia, hypothermia, hyperlipidaemia
E - ERCP
D - drugs - e.g. azathiaprin
What element is suggested to be raised in the final common pathway for pancreatitis?
What does this lead to?
What lifestyle factor can also influence this process?
the final common pathway has a marked rise in intracellular calcium
this leads to activation of intracellular proteases
there is evidence that alcohol interferes with calcium homeostasis in pancreatic acinar cells
What is the result of activation of intracellular proteases following an increase in intracellular calcium?
proteases digest the walls of blood vessels, leading to blood extravasation
amylase is released into the blood
(this is a non-specific diagnostic marker)
As well as amylase, what is released into the blood following blood extravasation?
What “sign” can this lead to?
released lipases are a better diagnostic marker than amylase
they cause fat necrosis within the abdomen and subcutaneous tissue
this can lead to discolouration of the skin - Grey Turner’s sign
What is Grey Turner’s sign?
this refers to discolouration of the skin / bruising of the flanks
it appears as a blue discolouration
this is a sign of retroperitoneal haemorrhage or bleeding behind the peritoneum
How can levels of calcium and glucose be affected in pancreatitis and why does this happen?
- fatty acids are released into the blood following extravasation and lipase release
these can bind to Ca2+ and lead to hypocalcaemia
- concomitant destruction of adjacent islets can lead to hyperglycaemia
this can then cause Type II diabetes
What can occur following necrosis and destruction of pancreatic tissue in pancreatitis?
- formation of abscesses or cysts within the pancreas or adjacent tissues can occur
- infection secondary to pancreatic tissue damage does not always occur, but can
- not all cases of infection lead to cyst / pseudocyst formation
Why can pulmonary failure occur in acute pancreatitis?
What does this eventually lead to?
pulmonary failure in acute pancreatitis is caused by circulating activated digestive enzymes
(e.g. phospholipase A2, trypsin)
this leads to a loss of surfactant, atelectasis and irritation
this eventually leads to ARDS and pleural effusion
What else can occur in acute pancreatitis as a result of circulating activated digestive enzymes?
- cardiac depression
- breakdown of the blood brain barrier
What is the main clinical feature of acute pancreatitis?
How does this change as inflammation spreads?
upper abdominal pain that usually starts in the epigastrium and is accompanied by nausea and vomiting
as inflammation spreads in the peritoneal cavity, the pain becomes more intense
involvement of the retroperitoneum frequently leads to back pain
What clinical features may be present in severe cases of acute pancreatitis?
- tachycardia
- hypotension
- oliguria (reduced urine output)
What might be seen on abdominal examination in acute pancreatitis?
- widespread tenderness with guarding
- reduced / absent bowel sounds
- periumbilical bruising (Cullen’s sign) and flank bruising (Grey Turner’s sign)
What is Cullen’s sign?
haemorrhagic discolouration of the umbilical area due to intraperitoneal haemorrhage of any cause
What does it mean if Cullen’s sign and Grey Turner’s sign are present?
if these signs are present they show severe necrotising pancreatitis
What sign, if present, is indicative of poor prognosis in acute pancreatitis?
left-sided pleural effusion
What will blood tests show in acute pancreatitis?
- raised serum amylase
- raised serum lipase
amylase is not prognostic and the level is not related to the degree of tissue damage
lipase levels are more specific and relate to the level of tissue damage, but levels do not rise until up to 8 hours after the onset of symptoms
What does raised amylase suggest?
raised amylase, many times above the normal level, is an important indication of pancreatic inflammation
Why might a chest X-ray be performed when diagnosing acute pancreatitis?
- CXR excludes gastroduodenal perforation, which also causes raised serum amylase
- CXR may show gallstones or pancreatic calcification
Why might an USS be performed in suspected acute pancreatitis?
What might this show?
USS is performed to look for gallstones which may cause pancreatitis
It may also show pancreatitic swelling and necrosis
Why might a contrast-enhanced spiral CT be performed in acute pancreatitis?
- to assess the extent of pancreatic necrosis
- to detect complications such as abscesses, fluid collection and pseudocyst formation
What is the purpose of performing an MRI in acute pancreatitis?
MRI (MRCP) assesses the degree of pancreas damage
it can be used to locate gallstones
it can also differentiate between fluid and solid inflammation
What is ERCP?
Why might it be used?
endoscopic retrograde cholangiopancreatography
this is used to look at the pancreatic duct for inflammatory fibrosis or tumours
pancreatic juice can be collected and biochemically examined