The Collison Newsletter August 2010


                      HAEMATURIA – Blood in the Urine*  

Haematuria is the technical term for blood in the urine. It is the presence of red blood cells in the urine.

Types of Haematuria 

·        Microscopic. In microscopic haematuria, the urine appears normal to the naked eye, but examination of the urine under a light microscope shows the presence of red blood cells. The red cells are only visible under a microscope, and they represent only a small amount of blood in the urine.

·        Macroscopic. Macroscopic haematuria, also known as ‘gross or frank haematuria’, is when the red blood cells are visible to the naked eye. They appear as spots of blood or blood clots in the toilet water or turning the water pink, bright red or reddish-brown.


There are other causes of red discolouration of the urine that are NOT haematuria. A red colour can appear in the urine suggestive of haematuria due to:

Myoglobin in myoglobinuria

Porphyrins in porphyria

Drugs such as Rifampicin

Eating certain foods such as beets, rhubarb and paprika

Haemoglobin - only the red pigment, not the red blood cells.


Both microscopic and macroscopic haematuria are always abnormal and invariably require investigation. The only exception is during menstruation.

Statistics of Haematuria 

The following statistics are from

·        Population prevalence of macroscopic haematuria is approximately 1%

·        Prevalence of microscopic haematuria is about 5%

·        50% of patients with haematuria will have an underlying abnormality

·        10% of patients with microscopic haematuria will have a urological malignancy

·        35% of patients with macroscopic haematuria will have an underlying tumour.


Johns Hopkins Medicine Health Alerts indicate that doctors can find no cause for haematuria in up to 10% of cases.

Causes of Haematuria 

Haematuria is the result of bleeding somewhere in the urinary tract, which is made up of the kidneys, the ureters (the tubes that take the urine from the kidneys to the bladder), the bladder, the urethra (the tube from the bladder to the outside world) and, in the male, the prostate.


There are many conditions that can cause haematuria, most of which are not life-threatening. However there are a number of serious causes of haematuria that need to be detected.

·        Trauma. Traumatic injury to any part of the urinary tract, from the kidneys to the urethral opening, can cause haematuria.

·        Urinary tract infection. Haematuria can be caused by an infection in any part of the urinary tract, most commonly in the bladder (cystitis) or the kidney (pyelonephritis).

·        Drugs. Haematuria can be caused by prescribed medications such as blood thinners (anticoagulants) including heparin, warfarin or aspirin-type medications and cyclophosphamide.

·        Cancers of the kidney of bladder (or prostate in males).

·        Stones or calculi. These can occur in the kidney, the bladder or the ureters.

·        Glomerulonephritis. Glomerulonephritis refers to a group of kidney diseases that have inflammation of the glomeruli, the filtering units of the kidneys. It can rarely be a complication of certain viral and bacterial infections. It can also occur in autoimmune disorders such as systemic lupus erythematosis (lupus or SLE) and diabetes mellitus.

·        Exercise. This is also called ‘march haematuria’, as seen in soldiers on extended marches. Very prolonged exercise in athletics, jogging, horseback riding and bicycle riding can cause haematuria, which is a non-serious condition.

·        Bleeding disorders, including genetic disorders such as haemophilia, can result in haematuria.

·        Inflammation/infection of the prostate can lead to haematuria.


Urinary tract infection and traumatic injuries are the most common causes of haematuria.

Diagnosis of Haematuria 

Both gross haematuria and microscopic haematuria can be evaluated in a doctor’s office.


Assessment must include taking a medical history and asking about recent food and drug intake, exercise and urological procedures. Specific features of the blood in the urine must be elicited including if there is any associated pain or irritation, whether blood appears at the beginning or at the end of the urine stream, how much blood is in the urine and if any blood clots are present. Of course, microscopic haematuria can only be diagnosed with microscopic examination of a urine sample. Genital and rectal examinations are also generally carried out (especially to look for prostate disease).


Doctors assume that painless, gross haematuria is the result of cancer until malignancy has been ruled out.

Tests that Assist in Making a Diagnosis: 

·        Urinalysis. A quick test using a dipstick can be done in the surgery looking for the presence of blood or protein in a urine sample. In the laboratory, the urine sample is examined under the microscope to look for the presence of red blood cells (confirming haematuria), white blood cells (suggesting infection) and protein (due to kidney inflammation or glomerulonephritis).

·        Urine culture. Urine is placed onto culture plates to see if bacteria grow (and to identify the type if present and the sensitivity to antibiotics). This is done to confirm whether a urinary tract infection is present and may be causing the haematuria.

·        Cytology. This looks for the presence of cancer cells in the urine.

·        Blood tests. These are carried out to check for signs of urinary tract infection, kidney failure, bleeding disorders etc.

·        Radiology. A range of tests include an intravenous pyelogram or IVP (an x-ray of the urinary tract using contrast) and a CT (computerised tomography) scan. These can reveal a tumour, a kidney or bladder stone, an enlarged prostate or other blockage to the normal flow of urine.

·        Cystoscopy. A flexible telescope is inserted through the urethra to view the bladder and the urethra. This test is usually done with local anaesthesia. Biopsies of any suspicious lesions seen may be taken during this procedure.

·        Renal biopsy. Here, a sample of kidney tissue is taken for examination under the microscope.

Treatment of Haematuria 

Treatment of haematuria depends on the cause. If no serious condition is causing the haematuria, generally no treatment is necessary.


Treatment depends on the exact cause, and treating the identified cause should stop the bleeding. For instance, if certain medications are causing the bleeding, these may need to be changed. Infections of the urinary tract will be treated with antibiotics. Cancers need specialist care.


A Urologist is a specialist who looks after the bladder, prostate and urethra. If the bleeding originates from kidney disease for which surgery would not be corrective (medical renal disease), follow-up with a Nephrologist would be necessary.


*Copyright 2010: The Huntly Centre.

Disclaimer: All material in the website is provided for informational or educational purposes only. Consult a health professional regarding the applicability of any opinions or recommendations expressed herein, with respect to your symptoms or medical condition.


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