igg4 pancreatitis dr chan lok lam laura united christian hospital jhsgr 6 th aug, 2011
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IgG4 PancreatitisDr Chan Lok Lam Laura
United Christian Hospital
JHSGR 6th Aug, 2011
IgG4 pancreatitisRecently described disorder with protean
manifestations
Important diagnostic consideration in patients with obstructive jaundice associated with pancreatic mass lesion
Mimics pancreatic cancer clinically and radiologically
Dramatic response to steroid
Correct diagnosis allows medical treatment and avoids major surgery
IgG4 pancreatitis = autoimmune pancreatitis?
In previous literature YES!
Concept evolving
Autoimmune pancreatitis (AIP)
Type I AIP (IgG4 pancreatitis)Pancreatic
manifestation of systemic IgG4-related disease
Type II AIPSpecific pancreatic disease occasional association with
ulcerative colitis
IgG4 pancreatitisChronic inflammatory disease of presumed
autoimmune origin
Pathogenesis not well understood
Lymphoplasmacytic infiltration with abundant IgG4 positive cells
Inflammatory process responds well to steroid therapy
EpidemiologyUncommon
0.82 per 100,000 patients in a Japanese nationwide survey (2002)
4.6-6% in patients with chronic pancreatitis
3-5% undergoing pancreatic resection for suspected pancreatic cancer
EpidemiologyElderly Male
Extra-pancreatic manifestations
Biliary strictures
Sclerosing sialadenitis
Retroperitoneal fibrosis
Sclerosing cholecystitis
Interstitial nephritis
Diffuse lymphadenopathy
Characteristic lymphoplasmacytic infiltrate rich in IgG4-positive cells
Can precede/ accompany / follow pancreatic involvement
Clinical presentationPainless obstructive jaundice (65%)
Vague abdominal pain
Weight loss
Exocrine insufficiency (88%)
Endocrine dysfunction (67%)
Laboratory findingsAmylase/ lipase: normal/ mildly elevated
Gamma globulin, total IgG, IgG4Commonly elevatedSerum IgG4 :
140 mg/dl: Sensitivity 76%; Specificity 93% 280 mg/dl: Sensitivity 53%; Specificity 99% Elevated in 7-10% cases of Pancreatic CA
(usually mild)
AutoantibodiesANA, RF: elevated (non-specific)
RadiologicalCT/ MRI:
Diffuse enlargement of the entire pancreas ‘sausage-like’
Low density capsule-like rim due to inflammation and fibrosis
Delayed contrast enhancement
CT/ MRIFocally enlarged pancreas ‘inflammatory mass’
ERCP/ MRCPDiffuse narrowing of main pancreatic duct
ERCP/ MRCPSegmental narrowing of main pancreatic duct
Biliary stricture ( can occur anywhere )
DifferentiationIgG4 Pancreatitis CA Pancreas
Narrowing of MPD > 1/3 or > 3cm
Pancreatic duct dilatation
Skipped, narrow lesions of MPD
Abrupt pancreatic duct cut-off
Side branches from narrow portion of MPD
Upstream pancreatic atrophy
Stricture of intrahepatic ducts
EUS guided FNACDetecting
adenocarcinomaSensitivity 70-90%Negative bx does not
rule out CA
Not for diagnosis of IgG4 pancreatitis Inadequate cellsLack of architecture
EUS guided core biopsy
Allow diagnosis of IgG4 pancreatitis
Technically difficult
Increased risk of bleeding
Not widely available
Biopsy of extra-pancreatic site
Bile ducts, major duodenal papilla
80% pancreatic head involvement had IgG4-positive cells on biopsy of the major duodenal papilla
Response to steroidDramatic
Response to steroidRadiographic response seen at 2-3 wks and
normalization at 4-6 wks
Response to steroidSteroid trial controversial
No response within 2 weeks makes IgG4 pancreatitis unlikely
Failed response to steroid Prompt re-evaluation of diagnosisConsider surgery to look for cancer
Making the correct diagnosis is challengingRare diseaseMimic the more common pancreaticobiliary
malignancyNo single diagnostic test available
Price of misdiagnosis is heavyUnnecessary surgery for benign diseaseDelay potentially curative surgery
Japanese Diagnostic Criteria
1. Imaging
- Diffuse/ segmental narrowing of main pancreatic duct
- Diffuse/ localized enlargement of pancreas
2. Serology
- Elevated gamma-globulin, IgG or IgG4 OR
- Presence of autoantibodies eg ANA/ RF
3. Histology
- Lymphoplasmacytic sclerosing pancreatitis
Diagnosis: 1 + 2/3
Take Home MessageIncreasing recognition
Important diagnostic consideration in obstructive jaundice due to pancreatic mass lesion
High index of suspicion
Multidisciplinary collaborationSurgeons/GI
physician/Radiologist/Pathologist
The END