Hematuria or blood in the urine indicates that bleeding is occurring somewhere in the urinary tract. The underlying cause of the condition therefore needs to be investigated and diagnosed so that an appropriate treatment can be prescribed.
The diagnosis of hematuria may involve multiple steps and a battery of tests, some of which are described below:
- A detailed medical history is obtained to help ascertain the underlying cause. For example, injury to the lower abdomen could damage the urinary tract and lead to hematuria or the presence of fever can indicate an infection that may be causing the condition. The most common cause of hematuria in men aged over 50 years is benign enlargement of the prostate.
- A dipstick test is often performed to check for the presence of blood that may not be visible to the naked eye. The urine sample is collected in a special container and a chemically treated strip of paper called a dipstick is placed into the urine. The color on the dipstick changes to indicate the presence or absence of blood in the sample.
- If the history of the patient is unremarkable with no indication of any cause of hematuria despite a positive dipstick test, a patient is asked to wait for 48 hours before the urine is tested again. If a series of two or three urine tests detect red blood cells, further testing is advised.
- Urine analysis – A urine sample is sent to the laboratory for analysis. A detailed look at the urine sample under the microscope can also provide clues as to the underlying causes of hematuria. For example, analysis may reveal the presence of white blood cells which would indicate infection or the presence of proteins which would indicate a kidney disorder. Cancer cells can also be detected under the microscope.
- Blood test – Blood may be tested to check for raised creatinine levels (indicating kidney disease), a raised white blood cell count (indicating infection) or abnormalities that indicate other conditions such as sickle cell anemia.
- Kidney biopsy – A biopsy may be recommended to confirm suspected cases of kidney cancer or other kidney disorders. A small piece of the kidney tissue is removed while the patient is under anesthesia and sent for analysis under the microscope.
- Cystoscopy – This is a form of endoscopy that uses a long, thin and flexible tube inserted through the urethra to examine the inside of the bladder. The cystoscope tube has a camera and a light source at its tip. The bladder is then checked for evidence of cancer or cysts, for example.
- Imaging studies – Imaging studies such as an ultrasound examination, a computed tomography (CT) scan or a magnetic resonance imaging (MRI) scan may be performed to create detailed images for the examination of structures in the urinary tract.