Hi.
I am assuming you are referring to rbc in the urine in men.
It means there is a problem somewhere along the tracts where urine passes.
The blood may come from the kidney, the ureter (a tube that connects the kidney to the bladder), the bladder, prostate, and the urethra (the lumen where urine passes).
In women, blood may be a contaminant from the vagina - so normal menstruation can contribute to this, outside this setting, bleeding may come from the cervix (the neck of the uterus) and the vaginal wall.
The description of the blood may help estimate where the bleeding is originating.
Consult a physician straight away and discuss it.
It is increase of red blood cell more than its usual range ( 4.2 - 5.9 x 1012 cells per liter).