Renal Vein Thrombosis: A Case Report Riyaz Bashir, MD, * Jodi Tinkel, MD, * and Deepak Malhotra, MD, †‡ United States The presenting symptoms of acute renal vein thrombosis (RVT) can often be confused with those of nephrolithiasis. Delayed diagnosis and treatment of RVT can result in catastrophic complications, including loss of renal function and pulmonary embolism. A high clinical suspicion and early imaging with computed tomography or magnetic resonance imaging will allow early initiation of therapy and prevention of thrombus extension in patients with RVT. Case Report A 40-year-old white man presented with com- plaints of severe and sudden onset of left flank pain with associated nausea and vomit- ing. He was given a presumptive diagnosis of nephrolithiasis and discharged home. For the next 2 days, his pain became unbearable, and he again presented to the hospital for further evaluation. Past medical history is significant for tobacco use and hyperlipidemia. His father had premature coronary artery disease at age 48 and eventually died due to mesenteric thrombosis and bowel ischemia at the age of 65. No other family history of thrombosis was present. On physical examination, he was noted to have a temperature of 101.6°F and signifi- cant left flank tenderness. Urinalysis showed mild proteinuria and microscopic hematuria. Contrast-enhanced computed tomography (CT; Figure 1) at an outlying hospital was suspicious for left renal vein thrombosis without any evi- dence of masses or hydronephrosis. Magnetic resonance venography (MRV; Figure 2) per- formed at our institution confirmed the diagno- sis of left renal vein thrombosis just distal to the Angiology 58:640–643, October/November 2007 From the * Division of Cardiovascular Medicine and † Division of Nephrology, Medical University of Ohio at Toledo, and ‡ Ruppert Health Center, Toledo, Ohio Correspondence: Riyaz Bashir, MD, Division of Cardiovascular Medicine, Medical University of Ohio at Toledo, 3000 Arlington Avenue Room 1192, Toledo, Ohio 43614 DOI: 10.1177/0003319707303646 ©2007 Sage Publications Angiology Volume 58, Number 5, 2007 640