Endoscopic resolution of esophageal varices in a patient with IgG4-related disease: a case report.

IgG4-related pancreatitis is a complex and multiorgan disease that can mimic pancreatic malignancy. Corticosteroids are the first-line therapy, but their use may not be an option for patients with metabolic comorbidities, such as diabetes mellitus. We report a rare case of a 58-year-old man who presented with portal hypertension and esophageal varices. The patient underwent pancreaticoduodenectomy for suspected pancreatic malignancy. However, a surgical pathology report retrieved during revision confirmed IgG4-associated autoimmune pancreatitis and documented diffuse sclerosing lymphoplasmacytic inflammation with dense periductal lymphoplasmacytic infiltrates, obliterative phlebitis, fibrosis/sclerosis, and increased IgG4-positive plasma cells (up to >50 per high-power field). Serum IgG4 was recorded as 5,521 mg/dL. Postoperatively, the patient developed insulin-dependent diabetes mellitus, precluding corticosteroid therapy. Rituximab was initiated and the dosing interval was subsequently shortened after PET findings were interpreted as possible systemic involvement. Following treatment, recorded serum IgG4 values progressively decreased to 17 mg/dL. Follow-up endoscopy in 2023, supported by paired endoscopic images, demonstrated no visible esophageal varices in the imaged segment. This case describes an unusual and clinically relevant temporal association. However, the available data do not establish resolution of portal hypertension or a causal relationship between rituximab and the endoscopic finding.