Download Pancreatitis Definition and Etiology

Pancreatitis
Dr. Gehan Mohamed
Dr. Abdelaty Shawky
Learning objectives
• Identify different types of pancreatitis.
• List various causes of pancreatitis as biliary stone,
alcohol and the mechanism of their action.
• Understand how to diagnose a case of pancreatitis
by the help of clinical presentation ,histopathologic
changes and imaging studies and differentiate it from
other causes of acute abdomen.
• Know the serious complications of pancreatitis.
Pancreatitis
• It may be:
1. Acute inflammation: occurs suddenly and
lasting for a few days. Usually heals by
regeneration without any functional or anatomic
changes.
2. Chronic inflammation: occurs gradually with
recurrent attacks . Heals by fibrosis that result in
endocrine and exocrine insufficiency.
* Pathogenesis of pancreatitis:
• It occurs when pancreatic enzymes (especially
trypsin that digest food) are activated in the
pancreas instead of the small intestine so it
autodigest the pancreas and surrounding
tissue
* Causes of pancreatitis:
(1) Chronic alcoholism.
(2) gallstones.
(3) Some medications such as diuretics, the
chemotherapeutic agents, steroid use .
(4) trauma.
(5) autoimmune disease.
(6) Infectious causes. Coxsackie virus, Cytomegalovirus,
Hepatitis B virus. Salmonella, Aspergillus, Toxoplasma
* Mechanism of pancreatitis caused by Biliary
Tract Stones :
The stone might have caused outflow obstruction from
a common biliopancreatic channel at the ampulla of
vater toward the intestine allowing so bile reflux into
the pancreatic duct with activation of the pancreatic
enzymes leading to digestion of the pancreas.
Biliary Tract Stones
Mechanism of pancreatitis caused by
Abuse of Ethanol:
1. Ethanol act directly on pancreatic acinar cells
to cause injury .
2. It promotes secretion of pancreatic juice that
is rich in proteolytic enzyme content but low in
enzyme inhibitors.
3. Secretion of an enzyme-rich fluid could also
lead to protein precipitation and the formation
of intraductal plugs.
* Diagnosis of pancreatitis:
1. Clinical picture
2. Laboratory Finding
3. Histopathologic changes
1. Clinical picture:
• severe upper abdominal pain radiating to the back.
• nausea, and vomiting.
• Blood pressure may be elevated by pain or
decreased due to dehydration or internal bleeding.
• The abdomen is usually tender.
• Fever or jaundice may be present.
• Unexplained weight loss may occur from a lack of
pancreatic enzymes hindering digestion.
• Fatty stools (steatorrhea).
(2). Laboratory Finding:
- Elevation of white count- 20,000-50,000.
- Elevated serum lipase and amylase(5 to 40 times)
(lipase is generally considered a better indicator).
- Abnormal low serum Ca due to Binding of Ca in areas of fat
necrosis.
- Abdominal ultrasound is generally performed first, for
detecting gallstones, diagnosing alcoholic fatty liver (combined
with history of alcohol consumption).
3. Histopathologic changes:
A. In mild acute pancreatitis: changes frequently
include interstitial edema and infiltration by
inflammatory cells with relatively little necrosis.
B. In severe acute pancreatitis: extensive
necrosis, thrombosis of intrapancreatic vessels,
vascular disruption, and intraparenchymal
hemorrhage can be seen.
C. In chronic pancreatitis: there is both loss of
pancreatic acini, islets of langerhans and fibrosis.
Gross pathology of acute pancreatitis
Chronic pancreatitis
Normal histology of pancreas
Microscopic picture of acute pancreatitis
Microscopic picture of acute pancreatitis
showing necrosis , inflammatory cells.
Microscopic picture of acute pancreatitis showing
necrosis , inflammatory cells.
Microscopic picture of chronic pancreatitis characterized by
loss of some pancreatic acini and replaced by fibrosis(arrow)
↑
* Complications of pancreatitis:
1. Shock.
2. Pancreatic abscess due to acute necrotizing
pancreatitis
3. Development of pancreatic pseudocysts which
is collections of pancreatic secretions that have
been walled off by scar tissue. These may cause
pain, become infected, rupture and bleed.
4. Chronic pancreatitis can lead to diabetes
mellitus or pancreatic cancer.