LAUSR

PURPOSE Chronic unilateral hematuria (CUH) is also called lateralizing essential hematuria, benign essential hematuria, and benign lateralizing hematuria, which was defined as intermittent or continuous gross hematuria that cannot be diagnosed with standard radiology and hematology studies, together with unilateral bloody efflux by cystoscopy. CUH is rare, but sometimes confused with malignancy or life-threatening hemorrhage. Therefore, it can cause considerable anxiety to not only patients but also urologists. For this study, we summarized articles about endoscopic diagnosis and treatment of CUH, and discussed the development of endourology for CUH. MATERIALS AND METHODS We searched articles related to CUH that were indexed in the PubMed database and published in English. Key terms used were "unilateral," "lateralizing," "chronic," "benign," and "idiopathic" hematuria. We found 15 pertinent articles reporting CUH. RESULTS Endoscopically, CUH can be classified into three categories: discrete lesion, diffuse lesion, or no (unidentified) lesion. Currently, endoscopic techniques for CUH are similar to the techniques for upper tract urothelial carcinoma, using semi-rigid and flexible ureteroscopes with diathermy fulguration or laser ablation for treatment. The overall success rate of endoscopic treatment for CUH, defined as resolution of gross hematuria after treatment, was 93% (190/205). The recurrence rate, defined as recurrent gross hematuria after treatment, was 10% (19/189). CONCLUSION Advancements in endoscopic devices and techniques have enabled more accurate and less invasive diagnosis and treatment of CUH. Once CUH is defined, flexible ureteroscopy is the diagnostic and therapeutic technique of choice.