1399 EXPERIMENTAL STUDY ON THE PATHOGENESIS OF CHRONIC UNILATERAL HEMATURIA IN A PORCINE MODEL: FOCUSING ON THE EFFECT OF AN ELEVATED BLOOD PRESSURE IN THE RENAL VEIN

Abstract

You have accessJournal of UrologyTechnology & Instruments: Ureteroscopy1 Apr 20111399 EXPERIMENTAL STUDY ON THE PATHOGENESIS OF CHRONIC UNILATERAL HEMATURIA IN A PORCINE MODEL: FOCUSING ON THE EFFECT OF AN ELEVATED BLOOD PRESSURE IN THE RENAL VEIN Soichi Mugiya, Masao Nagata, and Seiichiro Ozono Soichi MugiyaSoichi Mugiya Hamamatsu, Japan More articles by this author , Masao NagataMasao Nagata Hamamatsu, Japan More articles by this author , and Seiichiro OzonoSeiichiro Ozono Hamamatsu, Japan More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2011.02.1246AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Chronic unilateral hematuria is characterized by intermittent or continuous gross hematuria that cannot be diagnosed using standard radiology and hematology methods. We have evaluated patients with unilateral renal hematuria to determine the cause of bleeding and reported that the most common endoscopic findings were minute venous ruptures on the renal papilla (J Urol 178: 517, 2007). The causes for chronic unilateral hematuria include left renal bleeding (known as nutcracker syndrome) accompanied by an elevated renal venous pressure. There has been no report on endoscopic findings of nutcracker syndrome and the pathogenesis of chronic unilateral hematuria has not been clarified. In order to support the above derived from the clinical studies, we created a hypertension of the renal vein in a porcine model with an aim to analyze the pathogenesis of chronic unilateral hematuria and study endoscopic findings. METHODS The experimental model in this study was the female pig kidney. Two pigs (4 kidneys) with weights 60 kg were used. A catheter for measuring the intravenous pressure was inserted into the renal vein of a porcine under general anesthesia and connected to an intravascular blood pressure monitoring system. A renal vein occlusion was created to induce an elevated blood pressure and produce a phenomenon in which renal bleeding occurs. A flexible video uretero-renoscope (URF-V: Olympus, Japan) was used in combination with the narrow band imaging (NBI) system to observe how the capillaries change within the renal pelvis and calyces before and after an increase in blood pressure and study how renal bleeding occurs and how the renal intravenous pressure is associated with it. RESULTS An intravenous pressure of the renal vein showed a rapid increase upon occlusion. The pig's entire kidney with occlusion of the renal vein showed development of renal bleeding immediately after occlusion. When the intravenous pressure increased above the level of 50 mmHg, bleeding was observed from local ruptures of minute vessels in the mucous layer of the renal calyx. Bleeding from the ruptured minute vessels disappeared when the renal vein occlusion was removed. CONCLUSIONS Our experimental results suggest that congestion in the renal venous system can be a cause of hematuria. Elevated renal venous pressure-induced bleeding from locally ruptured minute vessels in the renal calyces was considered as a cause of chronic unilateral hematuria. © 2011 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 185Issue 4SApril 2011Page: e559-e560 Advertisement Copyright & Permissions© 2011 by American Urological Association Education and Research, Inc.MetricsAuthor Information Soichi Mugiya Hamamatsu, Japan More articles by this author Masao Nagata Hamamatsu, Japan More articles by this author Seiichiro Ozono Hamamatsu, Japan More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...