Introduction: Gastrointestinal (GI) bleeding in liver transplant recipients is diagnostically and therapeutically challenging, particularly when routine evaluations fail to identify a source. Rare vascular causes must be considered when standard workups are inconclusive. Presentation of case: A 23-year-old male with a complex history of four liver transplants over several years for chronic rejection related to medication noncompliance experienced recurrent episodes of obscure GI bleeding over months. Extensive evaluation – including multiple upper and lower endoscopies, nuclear tagged-red blood cell scans, and CT angiography – was repeatedly negative. Ultimately, provocative mesenteric angiography revealed a portobiliary fistula, felt to be iatrogenic following a percutaneous liver biopsy. The lesion was successfully treated with coil and gelfoam embolization, with complete resolution of bleeding and subsequent normalization of liver function tests. Discussion: This case highlights an uncommon vascular etiology of obscure GI bleeding in the transplant population. Portobiliary fistula/hemobilia should be considered in patients with recurrent, unexplained GI hemorrhage after liver biopsy or invasive hepatobiliary procedures. When intermittent bleeding eludes conventional imaging, provocative angiography can be diagnostic by unmasking occult, intermittent extravasation. Timely endovascular therapy can achieve durable hemostasis while preserving graft function. Conclusion: Clinicians should maintain a high index of suspicion for portobiliary fistula in post-biopsy transplant patients presenting with hemobilia or unexplained GI bleeding. Provocative angiography is a valuable tool for identifying occult bleeding sources, and endovascular embolization offers an effective, organ-sparing treatment. The case also underscores the critical need for strict adherence to immunosuppressive therapy to prevent graft loss and repeated transplantation.
Maraqah et al. (Wed,) studied this question.