Pancreatitis

Question 1

How does the pancreas protect itself from autodigestion : acute pancreatitis

Answer 1

Proteases released as inactive pro-enzymes

Pancreas contains trypsin inhibitor to prevent activation of trypsin

Enzymes only activated in duodenum

Question 2

What is the brush border enzyme that converts trypsinogen?

Answer 2

Enterokinase

Question 3

What is acute pancreatitis?

Answer 3

Rapid onset inflammation of the pancreas vs chronic long standing inflammation

Question 4

Acute pancreatitis Aetiology?

Answer 4

GET SMASHED

Gall stones

Ethanol

trauma

steroids

mumps / virus

auto-immune ( polyarteritis nodosa )

scorpian/snake bite

hypercalcaemia, hypertriglyceridaemia, hypothermia

ERCP

Drugs ( steroids, sulphonamides, azothioprine, NSAIDS, diuretics )

Question 5

Pathogenesis of acute pancreatitis?

Answer 5

↑ permeability of pancreatic duct epithelium (Alcohol, acetylsalicylic acid, histamine)
Acinar cell enzymes diffuse into periductal interstitial tissue

Alcohol ppts proteins in ducts → ↑ upstream pressure

Pancreatic enzymes activated intracellularly
proenzymes & lysosomal proteases incorporated into same vesicles → trypsin activated

Question 6

5 mechanisms of pancreatitis?

Answer 6

Pressure increase

Bile reflux

Reflux of activated enzymes from duodenum

Enzyme diffusion

Premature activation

Question 7

What can trypsin activation cause?

Answer 7

hypocalcemia

Hyperglycemia

Pancreatic gangrene

Pain

shock

hypoxia

anuria

Question 8

What types of acute pancreatitis are there?

Answer 8

Oedematous

haemorrhagic

Necrotic / infected necrosis

Question 9

Clinical symptoms of acute pancreatitis?

Answer 9

Epigastric pain radiating to back
often eased by sitting forward

N&V (vomiting +++)

Fevers

Question 10

Clinical signs of acute pancreatitis?

Answer 10

Haemodynamic instability (tachycardic, hypotensive)

Peritonism in upper abdomen/generalised

Grey-Turner’s sign (bruising in flanks)

Cullen’s sign (bruising around umbilicus)

(Grey Turner’s & Cullen’s signs seen in heamorrhagic pancreatitis

Question 11

Differential diagnosis of acute pancreatitis?

Answer 11

Gallstone disease & associated complications (e.g. biliary colic & acute cholecystitis)

Peptic ulcer disease/perforation

Leaking/ruptured AAA

Question 12

Investigations for acute pancreatitis?

Answer 12

Blood tests
Amylase/lipase 
other causes of ↑ amylase include:
Parotitis
renal failure
Macroamylasaemia
bowel perforation
lung/ovary/pancreas/colonic malignancies can produce ectopic amylase) 

X rays
Erect CXR
AXR (sentinal loop, GS)

Investigations

USS
look for GSs as cause for pancreatitis

CT abdomen
patients not settling with conservative management & only 48-72 hrs after symptom onset

MRCP
If GS pancreatitis suspected with abnormal LFTs (CBD stone)

ERCP
To remove CBD GS

Question 13

Assess severity of Acute P with Glasgow criteria?

Answer 13

PO2 <8KPa

age >55yrs

WCC >15

calcium <2mmol/L

renal: urea >16mmol/L
enzymes: AST >200iu/L, LDH >600iu/L

Albumin <32g/L

sugar >10mmol/L

Score of 3 or > within 48hrs of onset - suggests severe pancreatitis

CRP is an independent predictor of severity
>200 suggests severe pancreatitis

Question 14

Management of acute pancreatitis?

Answer 14

Fluid resuscitation (IV fluids, urinary catheter, strict fluid balance monitoring)
Analgesia
Pancreatic rest (+/- nutritional support if prolonged recovery [NJ feeding or TPN])
Determining underlying cause

95% settle with conservative treatment

If severe pancreatitis on scoring –> HDU

Antibiotics controversial –> commence if necrotic pancreatitis/infected necrosis, but not routinely

Surgery only very rarely required

Question 15

Systemic complications of acute pancreatitis?

Answer 15

Hypocalcaemia
lipase → FFAs → chelate Ca2+ salts → ↓ serum levels (saponification)

Hyperglycaemia (diabetes if significant beta cell damage)

SIRS (Systemic Inflammatory Response Syndrome)
ARF (Acute Renal Failure)
ARDS (Adult Respiratory Distress Syndrome)
DIC (Disseminated Intravascular Coagulation)
MOF (Multi Organ Failure) & death

Question 16

Local complications of acute pancreatitis?

Answer 16

• Pancreatic necrosis +/- infection (infected necrosis)
• Pancreatic abscess
• Pancreatic pseudocyst
• Haemorrhage: due to bleeding from erroded vessels
  Small vessels –> haemorrhagic pancreatitis (Cullen’s/Grey Turner’s sign)
  Large vessels (e.g. Splenic artery)
  –> life threatening bleed (unless forms pseudoaneurysm)

Thrombosis of splenic vein, SMV, portal vein (in order of frequency)

 - > ascites
 - > small bowel venous congestion/ischaemia

Chronic pancreatitis/pancreatic insufficiency (if recurrent attacks)

Question 17

How to manage infected necrosis AP?

Answer 17

Antibiotics + Percutaneous Drainage (?Surgery)
Infected pancreatic necrosis only indication for surgical intervention in the context of acute pancreatitis
high mortality if dead infected tissue is not debrided

Surgery involves necrosectomy (excision of necrotic tissue)

Question 18

What is a Pancreatic pseudocyst?

Answer 18

peri-pancreatic fluid collection
↑ [pancreatic enzymes] within a fibrous capsule
presents >6 weeks after pancreatitis

95% spontaneously resolve over 6 months
require no intervention unless:

• Pseudocyst symptomatic (pain)
• Pseudocyst causing compression of surrounding structures e.g. CBD (obstructive jaundice), duodenum (high SBO)
• Pseudocyst infected (abscess)

These 3x situations pseudocyst → drained

Question 19

How to manage pancreatic pseudocyst?

Answer 19

Percutaneously under radiological guidance (CT)
Endoscopically - EUS puncturing posterior wall of stomach & inserting stent
Surgically via laparoscopic/open:
pseudocystgastrostomy (cyst opened into stomach)
pseudocystjejunostomy

Question 20

Describe the chronic pancreatitis inflammatory process?

Answer 20

Destroys endocrine & exocrine tissue → fibrosis of pancreas

Insulin-dependent diabetes mellitus & steatorrhea

Question 21

Chronic pancreatitis management?

Answer 21

Surgical resection
Surgical drainage
Endoscopic

Question 22

chronic pancreatitis effects?

Answer 22

Tissue atrophy
Ductal stenosis
Periductal fibrosis

Pain
Malabsorption
Weight loss

Diabetes mellitus
Pancreatic ascites
Thrombosis of portal and splenic vein

Obstructive jaundice
Diarrhea
Pseudocysts