When i urinated there was a lot of blood. i went to the er and had ultra snd. put on antibiotics which cleared up the urine. the ultra sound showed nothing out of the ordinary on the kidneys or the bladder and the anitbiotics cleared up the urine within

An : An ultrasound will show if there are any abnormal tissues or fluids in the organs. Per the radiologist and based on these results, more tests (such as ct scans and procedures) can be done to assist with diagnosis. Since the ultrasound would lend to the presence of a tumor or other abnormality, i agree with your doctor that a ct scan is not necessary, since the purpose of a ct scan is to get a deeper view of tissue abnormality. Blood in the urine can be indicative of an infection such as a UTI or bladder infection which would not necessarily produce a result via ultrasound. Since antibiotocs cleared blood in your urine, they seemed to have treated the infectious process that was occuring. If you experience ongoing pain, blood in urine or trouble urinating, follow up with your doctor.

UTI: Sounds like you had a urinary tract infection wich damaged a superficial artery in your bladder, this has the technical term of hemorrhagic cystitis.