IgG4 related disease!

Thanks to John for presenting the case of a middle aged man from Vietnam with history of smoking who presented to the hospital with painless jaundice with imaging concerning for malignancy, found to have IgG4 related autoimmune pancreatitis!


Clinical Pearls

  • For imaging of the biliary tree:
    • Ultrasound is best for stones
    • CT is better for parenchymal disease
    • ERCP/MRCP is best for intraductal masses or stones
  • IgG4 related disease is more common in men >50 years of age.  It can affect many organs, similar to sarcoid.
  • It is an inflammatory and fibrotic systemic conditions where organs form tumefactive lesions rich in IgG4 plasma cells.
  • Diagnosis requires biopsy.  Serum IgG levels may be normal even in active disease.  However, a significantly elevated level is highly sensitive/specific (>95%) for IgG4 related disease.
  • Treatment involves steroids + immunomodulating therapy.

Approach to high bilis!

conjugated hyperbili

unconjugate hyperbili

DDx for painless jaundice:

  • Cancer (pancreatic, cholangiocarcinoma)
  • Meds/toxins
  • Viral hepatitis
  • ESLD
  • CHF
  • Hemolysis
  • PBC/PSC

IgG4 related disease

  • First described in 2003
  • Majority men (62-83%) and > 50 years of age.
  • Inflammatory and Fibrotic systemic condition where organs have tumefactive (tumor forming) lesions with an infiltrate rich in IgG4 plasma cells and often elevated IgG4 serum levels (but not always!)
  • The pathophys is poorly understood but thought to be a combination of autoimmune and allergic mediated processes.

Clinical features:

  • Subacute onset, typically few systemic signs/symptoms
  • 30% of those with autoimmune pancreatitis also have tubulointerstitial nephritis at presentation.
  • Pancreatic involvement 
    • Manifestations include a uniformly enlarged pancreas (sausage pancreas on imaging), pancreatic mass which can mimic cancer, recurrent pancreatitis, or strictures.
  • Biliary involvement
    • Biliary strictures leading to obstructive jaundice as well as sclerosing cholangitis
  • ANY organ can be affected (eg: thyroiditis, interstitial nephritis, salivary involvement), much like sarcoid

Spectrum of IgG4-related disease

IgG4 spectrum
Source: UpToDate

Diagnosis:

  • Need tissue biopsy for diagnosis.  Serum serologies are only suggestive.

Treatment:

  • Steroids + immunomodulating therapy.  

Chronic pancreatitis

Etiologies of Chronic Pancreatitis (progressive inflammatory changes in the pancreas that result in permanent structural damage and histologic fibrosis)

  • Alcohol abuse(45%) as well as cigarette use
  • Recurrent acute pancreatitis
  • Genetic (eg: CFTR, SPINK mutations)
  • Chronic ductal obstruction
  • Systemic diseases (eg: SLE, hyperparathyroidism, hypertriglyceridemia)
  • Idiopathic
  • Autoimmune: Can be Type 1 (part of IgG4 related disease) or Type 2 (idiopathic) 

Clinical manifestations of chronic pancreatitis

  • Can be ASYMPTOMATIC
  • Epigastric abdominal pain most common symptom however
  • Pancreatic insufficiency (only after 90 %of pancreatic function lost) and manifests as steatorrhea and glucose intolerance/diabetes
  • Remember that chronic pancreatitis puts you at increased risk for PANCREATIC CANCER

Lab/Imaging

  • Amylase/Lipase usually NORMAL so not as helpful
  • 72 hour quantitative fecal fat (steatorrhea alone is non-specific!)
  • Fecal elastasehas high sensitivity and specificity for chronic pancreatitis
  • KUB can show calcificationshinting towards chronic pancreatitis and MRCP/ultrasound can show pancreatic duct obstructions, dilations, strictures or fluid collections

Treatment

  • Alcohol and smoking cessation!
  • Creon supplementation, may also need fat-soluble (A,D,K,E) supplementation
  • Analgesics for abdominal pain which is extremely hard to control. Minimize opioids but may be necessary for refractory pain.
  • Specialized approaches include celiac nerve blocks, endoscopic surgery and surgical resection

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s