The causes of hematuria are briefly outlined and an approach to the diagnosis of this common finding is suggested. All cases require investigation, since even less than ten RBCs per high-power field may be the first sign of a malignant neoplasm or other serious disease. The most common causes are stones, malignant neoplasm, urethrotrigonitis, bacterial infection, prostatic hypertrophy, and glomerulonephritis; however, there are many other conditions to be kept in mind. A few simple laboratory tests will detect easily diagnosed problems such as bacterial infection, while more extensive and invasive studies are reserved to identify malignant neoplasms and other conditions in the remaining cases.
