Bilateral Renal Hypoperfusion Following Motor Vehicle Accident

Renal hypoperfusion noted on abdominal computed tomography (CT) scan without any underlying comorbid condition is a rare finding. Most reported cases of renal hypoperfusion have an association with an underlying cardioembolic problem, such as atrial fibrillation, endocarditis, cardiomyopathies, or artificial valve thrombi. We present a case of transient renal hypoperfusion evident on abdominal CT scan following blunt trauma. An 18-year-old male without any significant past medical history presented to the emergency department with the complaint of abdominal pain. The patient reported history of motor vehicle accident 1 week prior to his presentation. He was a front seat passenger wearing a seatbelt when the car went into a ditch. Airbags were deployed and the patient briefly lost consciousness. He presented 1 week later with complaints of generalized abdominal pain, more on the left side that started a few days after his accident, nonradiating, constant, 4/10 intensity. He denied dysuria, hematuria, groin pain, fever, chills, nausea, vomiting, abdominal pain, diarrhea, constipation, decreased oral intake, joint pain, leg swelling, or redness. He denied any medication use or any history of intravenous drug abuse. There was no reported family history of kidney disease or blood clots. Initial laboratory tests, including complete blood count, basic metabolic panel, erythrocyte sedimentation rate, and urinalysis were unremarkable except trace protein on the urinalysis. Contrast-enhanced CT of the abdomen showed multiple, confluent, focal areas of hypoperfusion of the renal parenchyma bilaterally. Given the CT findings of bilateral renal hypoperfusion, the patient was admitted to the hospital and an extensive workup was performed to rule out cardioembolic etiology. Echocardiogram, renal ultrasound, magnetic resonance angiogram of the abdomen, vasculitis panel, and hypercoagulable workup was unremarkable. The CT findings of renal hypoperfusion were considered secondary to transient hypoperfusion from blunt trauma. Abdominal pain resolved with nonsteroidal anti-inflammatory drugs and he was discharged to home. Follow-up abdominal CT scan with contrast obtained a few months later showed normal kidneys with resolution of previously noted renal hypoperfusion. Our case highlights a benign incidental finding of bilateral renal hypoperfusion following motor vehicle accident (with airbag injury), which resolved on follow-up imaging. On literature search, such CT scan findings of transient renal hypoperfusion of unclear significance have not been previously reported. Even though our patient underwent extensive workup to rule out cardioembolic etiology, it may be reasonable to forego such workup following blunt abdominal trauma.