Vicarious excretion of intravenous contrast masquerading as a nephroenteric fistula in a patient with a grade IV renal injury

We describe a case of a patient who suffered a grade IV renal injury who demonstrated vicarious excretion of intravenous contrast into the bowel masquerading as a nephroenteric fistula. Despite concerning imaging features, given the patient's lack of clinical symptoms of a nephroenteric fistula, negative oral activated charcoal test, and our understanding of the pharmacokinetics of intravenous contrast, our suspicion for nephroenteric fistula was low. This case highlights the importance of carefully considering the mechanism of injury when developing a differential diagnosis of potential sequela after trauma and understanding the pharmacokinetics of intravenous contrast in the trauma setting.