Disorders that cause biliary obstruction are common causes of jaundice and asymptomatic hyperbilirubinemia. In the elderly, such symptoms raise concern for a pancreatic carcinoma that compresses the common bile duct, particularly when the patient presents in conjunction with weight loss, asthenia, and imaging concerning for a mass. Autoimmune pancreatitis (AIP), however, is an infrequently recognized disorder that presents similarly to pancreatic cancer, and must be considered when evaluating etiologies of obstructive jaundice. The prevalence of AIP is estimated to be 0.82 per 100,000 based on limited literature. The true prevalence of AIP is uncertain with most literature coming from studies in Japan although the disease is being increasingly recognized worldwide.
Case Description:
A 72 year-old-male no significant history initially presented to an outside hospital with jaundice, …show more content…
Our patient was an older male with a significant history of alcohol consumption in addition to presenting with jaundice and imaging concerning for a malignant mass. Nevertheless, once a tissue biopsy is negative for malignancy, AIP should be high on the differential. AIP often presents as a focal pancreatic mass and obstructive jaundice, and as such is often confused with pancreatic carcinoma as in our case. It is also important to note that AIP can affect multiple organs including the kidneys, salivary glands, bile ducts, lungs, bowel and thyroid. In our case, the patient had acute renal failure and obstructive jaundice secondary to biliary strictures, which further supported a diagnosis of AIP. In regards to lab values, the patient’s elevated IgG4 is not as diagnostic as one may expect as up to 10 percent of those with pancreatic cancer have IgG4 levels up to 280 mg/dL. Nevertheless, the disproportionate rise in alkaline phosphatase compared to ALT/AST seen here is fairly typical of