Sump syndrome following hepaticojejunostomy: a case report of IgG4-related sclerosing cholangitis.

This report presents a case of IgG4-related sclerosing cholangitis (IgG4-SC) in a patient who ultimately died from a complex postoperative infection. The patient was a 59-year-old male who underwent resection of a hilar lesion and Roux-en-Y hepaticojejunostomy (RYHJ) for obstructive jaundice 7 years ago, with postoperative pathology confirming IgG4-SC. However, from 4 months after surgery, the patient experienced recurrent fever episodes that persisted for 7 years. The clinical presentation was consistent with sump syndrome. Both recurrent infections and IgG4-SC disease activity can elevate IgG4 levels, complicating clinical assessment. Despite aggressive antibiotic therapy combined with immunosuppressive treatment, the infections recurred. The patient eventually succumbed to sepsis in August 2025, triggered by recurrent cholangitis. This case underscores the importance of differentiating IgG4-SC from hilar cholangiocarcinoma (HC) to avoid unnecessary surgery. Moreover, it highlights that in post-hepaticojejunostomy patients, distinguishing whether elevated IgG4 levels signify disease activity or are secondary to infection is essential for guiding therapy.