S6030 A Dark Clue to an Unusual Link—Reno-Duodenal Fistula Presenting as Melena

Introduction: The prevalence of duodenal fistulas is rare and causes are limited. Perforation of peptic ulcers, severe pancreatitis, complications of intervention such as gastrectomy and endoscopic retrograde cholangio-pancreatography (ERCP) as well as some malignancies have been found to be the causes of duodenal fistulas. Reno-duodenal fistulas are especially rare and account for <1.0% of fistulas found between the gastrointestinal and urinary tracts. Chronic inflammation in the kidneys may lend to fistulization with the duodenum due to their close proximity. We present a rare care of reno-duodenal fistula causing gastrointestinal bleeding. Case Description/Methods: An 86-year-old man with history of hypertension, hyperlipidemia, diabetes, H. pylori gastritis and anemia initially presented for generalized weakness, lower abdominal pain and 4 days of melena. On arrival, the patient's lab work was notable for acute anemia and leukocytosis. Computerized tomography Abdomen and Pelvis scan was notable for complete cystic and solid irregular degeneration of the right kidney with associated focal emphysema. He was admitted and his hospital course was notable for multiple episodes of melena requiring blood transfusions. Inpatient esophagogastroduodenoscopy (EGD) performed for the evaluation of melena revealed a 15 mm fistula in the second portion of the duodenum surrounded by clotted blood. Biopsies of the surrounding abnormal mucosa were consistent with metastatic carcinoma, consistent with renal origin and kidney biopsy confirmed the diagnosis of renal cell carcinoma. Following goals of care discussion, the patient was discharged to hospice. Discussion: The presentation of melena in our patient with newly diagnosed renal cell carcinoma secondary to a reno-duodenal fistula emphasizes the need to include fistula formation on the differential when investigating gastrointestinal bleeding. Our case also highlights that although computed tomography imaging did not indicate the presence of a fistula, emphysematous changes should prompt concerns not only of local inflammatory process but also of involvement of nearby air containing structures such as the luminal gastrointestinaI tract as well. This case draws to light the need to maintain a broad differential including rare presentations, particularly when patients are presenting with atypical symptoms for upper gastrointestinal bleeding.