Spontaneous Renal Artery Thrombosis: A Rare Cause Of Acute Flank Pain

28 Nov, 2020 ,

Hee Joong Lim et.al. report the case of a 61-year-old man who presented with left flank pain. A contrast-enhanced CT revealed near-complete infarction of the left kidney and thrombotic occlusion at the left proximal renal artery. This was confirmed by renal artery angiogram. Interventional radiology treatment was planned for the patient and he underwent cannulation of the occluded segment and thrombolysis which led to the resolution of the patient's symptoms.

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A 61-year-old man presented left flank pain the day before seeking medical attention. He had no known medical history and thus no history of abdominal aortic aneurysm or a previous vascular intervention.

A physical examination provided the following vital signs: body temperature of 36.6°C, blood pressure of 174/115 mmHg, heart rate of 81 beats per minute, respiratory rate of 16 breaths per minute, and oxygen saturation of 99% on room air acquired from pulse oximetry. No significant findings were found on the results of complete blood count, blood chemistry, electrolytes, and coagulation profile including the D-dimer test, except for an increase in lactate dehydrogenase (LDH) to 1087 U/L and a serum blood urea nitrogen/creatinine level of 13.3/1.39 mg/dL. In addition, the echocardiogram showed a normal sinus rhythm. The patient underwent a contrast-enhanced computed tomography examination for further evaluation. The scan revealed near-complete infarction of the left kidney and thrombotic occlusion at the left proximal renal artery without underlying anatomic abnormality of the renal artery.

We decided to use thrombolytics through percutaneous intervention given that no contraindication existed for this treatment. Through the right femoral artery, a renal artery angiogram was obtained. It showed near-total thrombotic occlusion of the left proximal renal artery and nonvisible distal flow. The occlusion segment of the left renal artery was cannulated with a 1.7F microcatheter (Progreat Lambda; Terumo, Somerset, NJ, USA) and a 0.016-inch microwire (Meister; Asahi Intecc, Nagoya, Japan). Once the occluded area was traversed by the microwire, selective injections showed no dissection of the intrarenal branches. Thrombolysis was performed by placing a 7 cm multisideport catheter infusion set (Cook Medical, Bloomington, IN, USA) into the thrombosed left renal artery. First, urokinase was infused at 40,000 IU/h, and the patient was placed on intravenous heparin followed by oral warfarin. No adverse effects occurred, and abdominal pain disappeared immediately. Arteriography was performed after 13.5 hours to evaluate the response of thrombolysis and correct the catheter position. Infusion continued for additional 18.5 hours for resolution of the remaining thrombus burden. The subsequent arteriogram demonstrated a substantially lower thrombus extent and partial recanalization of the left renal artery. Further medical evaluation was performed aiming to identify the hyperviscosity syndrome. The normal levels of protein C, protein S, and antithrombin III allowed to discard the most common primary hypercoagulable states. The significance of the positive rheumatoid factor remained unknown. Finally, we confirmed the diagnosis of spontaneous renal artery thrombosis. The patient was discharged with resolution of his symptoms and normal vital signs with decreased serum blood urea nitrogen/creatinine level to 15.3/1.10 mg/dL.