Pancreas and Gall bladder pathology Flashcards
What does the following image show? (Hint: it’s healthy tissue)
Exocrine component of the pancreas
What does the image show? (Hint: it is healthy tissue)
Endocrine component of the pancreas
- What is acute pancreatitis?
- Risk factors
- Acute inflammation of the pancreas caused by aberrant release of pancreatic enzymes.
- Alcohol and drugs
What are the causes of acute pancreatitis?
Duct obstruction:
- Gall stones (50%)
- Trauma
- Tumours
Metabolic/toxic:
- Alcohol (33%) - 5% of alcoholics develop acute pancreatitis
- Drugs e.g. thiazide
- Hypercalcemia (acute pancreatitis with other causes can cause hypocalcaemia)
- Hyperlipidemia
Poor blood supply:
- Shock
- Hypothermia
Infection/inflammation:
- Viruses (Mumps, which is a virus that affects glands, so can affect glands in the pancreas)
- Autoimmune
- Idiopathic (15%)
Describe the pathogenesis of duct obstruction, and how it can lead to acute pancreatitis
Gallstone stuck distal to where the common bile duct and pancreatic duct joins leads to reflux of the bile up the pancreatic duct followed by damage to acini and release of proenzymes which then become activated.
Alcohol leads to spasm/oedema of Sphincter of Oddi and the formation of the protein rich pancreati fluid which obstructs the pancreatic ducts
What type of injury to the pancreas does infection/inflammation cause? (everything apart from duct obstruction)
Direct acinar injury
Acute pancreatitis: patterns of injury:
Describe the patterns of injury ofthe following and what causes it
- Periductal
- Perilobular
- Panlobular
- Periductal - necrosis of acinar cells near ducts (usually secondary to obstruction)
- Necrosis at the edges of the lobules (usually due to poor blood supply
- Panlobular - develops from 1 and 2
Describe the pathogenesis of injury to the periductal and periorbital areas of the pancreas
Activated enzymes –> acinar necrosis –> enzyme release etc.
Ranges from stromal oedema, to haemorrhagic necrosis
e.g. Lipases –> fat necrosis - calcium ions bind to free fatty acids forming soaps wihc are seen as yellow-white foci
Describe the following regarding acute pancreatitis:
- Complications
- Prognosis
1.Complications:
- Pancreatic - pseudocyst (an accumulation of fluid without an epithelial lining), abscess
- Systemic - shock, hypoglycemia, hypocalcemia
- Prognosis:
* Overall mortablity up to 50% for haemorrhagic pancreatitis
What does this image show?
Fatty deposition in the pancreas in acute pancreatitis
What is chronic pancreatitis?
Relapsing or persistent inflammation of the pancreas, associated with acute pancreatitis
Why are many cases of chronic pancreatitis linked to acute pancreatitis?
Mild acute pancreatitis can heal itself and regenerate. Very bad acute pancreatitis can lead to chronic pancreatitis and long term damage leading to persistent/chronic pancreatitis
What are the causes of chronic pancreatitis?
Metabolic/toxic:
- Alcohol (80%)
- Haemachromatosis - Fe desposited in the pancreas, affecting both exocrine and endocrine components
Duct obstruction:
- Gallstones
- Abnormal pancreatic duct anatomy
- Cystic fibrosis “mucoviscoidosis”
Tumours
Idiopathic - autoimmune
- What is the pathogenesis of chronic pancreatitis?
- What is the pattern of injury for chronic?
- Same as acute pancreatitis - obstruction or metabolic components can lead to release of enzymes causing necrosis and inflammation of the pancreas
- chronic inflammation, as in 1, with parenchymal fibrosis and loss of parenchyma. Duct strictures withe calcified stones occur, causing secondary dilatations
What are the complications of chronic pancreatitis?
- Malabsorption
- Diabetes mellitus
- Pseudocysts (which can lead to abscess formation so need to be removed)
- Carcinoma of the pancreas
What does this image show?
Pancreatic calcifications - diagnostic of chronic pancreatitis