Hematuria simply means blood in the urine.
Microscopic hematuria means that the blood is only seen when the urine is examined under a microscope. Gross hematuria, on the other hand, means that there is enough blood in the urine so that the change can be appreciated with the naked eye. Obviously, gross hematuria has more blood in the urine than microscopic hematuria, but the types of diagnoses that can cause the problem are the same and the work-up or evaluation that is needed is identical. To understand the needed evaluation for hematuria, one must know the anatomy of the urinary tract in the male. A diagram of the urinary tract may be provided so that the explanation makes better sense.