Immunoglobulin G4-related pancreatitis presenting as an obstructive pancreatic mass in a Latino male

Immunoglobulin G4-related disease (IgG4-RD) is a localized or diffuse autoimmune fibro-inflammatory condition that can affect any organ. The literature is sparse on IgG4-RD in the Latino population. This is a case report of a Latino male diagnosed with IgG4-related pancreatitis presenting as a mass. Our 40-year-old Latino male patient presented with diarrhea and epigastric discomfort progressing to jaundice and pruritus. He had associated elevations in liver enzymes, antinuclear antibody, and IgG4. Magnetic resonance cholangiopancreatography revealed a lobulated pancreatic head mass with common bile duct (CBD) narrowing. Endoscopic ultrasound-guided biopsy of the pancreas revealed no malignancy, and the patient underwent CBD stenting through endoscopic retrograde cholangiopancreatography. The patient demonstrated a favorable response to systemic glucocorticoid therapy with resolution of his symptoms and normalization of his liver function tests. Coronavirus disease-2019 infection during treatment had no impact on the outcomes.