What is haematuria?
Haematuria is blood in the urine. This is not a normal finding, but it is not uncommon and, has many possible causes. Your doctor will want to investigate further to find the cause of the blood.
Blood in urine may be easily visible or it may be present in such tiny amounts that it is only detected during a medical examination when a urinalysis (or dip stick test) is performed. Urine is normally clear and a shade of yellow that varies from pale straw to light amber, depending on the concentration of the urine. The colour of urine is frequently different when there is blood in it, but it may not necessarily be red.
- If there is enough blood present, the urine may be pink, red, brown or tea-coloured. This is also called gross or visible haematuria.
- When blood in urine is not visible and is only present in very small amounts, this is called microscopic haematuria. Microscopic haematuria will not alter the colour of the urine.
Many of the causes of haematuria involve the urinary tract, which consists of two kidneys, two ureters, a bladder, and a urethra.
- Urine is produced continuously by the kidneys as they filter wastes out of the blood.
- Urine moves from the kidneys through the ureters into the bladder, where the urine is stored, before being eliminated through the urethra during urination.
Some causes of haematuria are benign, temporary states that do no lasting harm and resolve with little or no specific treatment. Some causes, however, may be due to more serious conditions. To determine the cause of haematuria, and decide what treatment (if any) is required, your doctor will make an assessment based on your symptoms, medical history, physical examination and the results of any investigations undertaken.
This may include asking questions, such as:
Is it really blood?
A number of other things can cause urine to change colour e.g.
- Reddish-brown colouring can also come from eating foods such as beetroot and rhubarb or taking medication such as rifampicin.
- Haemoglobinuria is the presence of haemoglobin in the urine. Some conditions (e.g. sickle cell anaemia) cause red blood cells to break apart (haemolyse) and release haemoglobin, the iron-containing protein that gives red blood cells their colour. The excess haemoglobin is eliminated through the urine, causing it to turn red or tea-coloured.
- Bilirubin is a breakdown product of haemoglobin normally removed by the liver, but it can accumulate when the liver is damaged or diseased, and can cause urine to be a dark amber colour.
Is the blood from the urinary tract?
Contaminating blood may find its way into the urine from:
- Vaginal bleeding in women, such as from menstruation (periods)
- Haemorrhoids
Is it due to an infection?
Infections can sometimes cause cloudy, smelly urine, with painful urination, and occasionally haematuria.
- Urinary tract infections (UTIs)— are usually caused by bacteria and cause inflammation of the bladder (cystitis)
- Kidney infection—UTIs can sometimes spread to the kidneys.
Is the blood from a single isolated incident or from a known cause?
Sometimes blood may appear and then go away without the cause ever being identified. In other cases, it may be from an identifiable, resolvable or self-limited cause, such as:
- Strenuous exercise
- Fever
- Exposure to toxins, such as contrast dyes used in radiologic procedures (X rays or CT scans)
- Medications such as nonsteroidal anti-inflammatory drugs (NSAIDs), aspirin, or blood thinners that inhibit clotting and may increase the risk of a person having bleeding episodes with blood in the urine
- A medical procedure that physically involves part of the urinary tract, such as surgery, a kidney biopsy, or inserting a urinary catheter, can cause temporary bloody urine.
- Physical injury to the kidney or bladder, such as trauma
- An isolated incident (cause never identified)
Is the haematuria due to an inflammation or irritation of the urinary tract (or prostate in men) or due to blockage by, or the passage of, a kidney stone?
The following can cause blood in the urine and sometimes radiating pain, painful urination, urinary urgency (sudden urge to pee), and/or urinary hesitancy (difficulty in getting started):
- Urethritis—inflammation of the duct that carries urine from the bladder out of the body (urethra)
- Prostatitis—inflammation of the prostate (which surrounds the urethra in men)
- Benign prostatic hyperplasia (BPH)
- Kidney stones or bladder stones
Is it caused by kidney disease or a condition that can cause kidney damage?
- There are a variety of kidney diseases that can cause haematuria. An example is glomerulonephritis, a kidney disease associated with the filtering units in the kidneys (glomeruli).
- Diabetes and high blood pressure (hypertension) are common causes of kidney damage and can sometimes result in haematuria.
- Polycystic kidney disease is an inherited disorder that can lead to the formation of cysts in the kidneys and can lead to kidney disease.
Is haematuria due to some other disease or condition within the urinary tract?
- Structural abnormalities within the urinary tract can cause bleeding.
- Blood clots can form within the urinary tract.
Is the haematuria due to some other underlying chronic and/or inherited disorder?
This may be a disorder that affects the body as a whole (systemic) or that results in excess blood within the urinary tract, leading to haematuria. Some examples include:
- Bleeding disorders—these can lead to excessive bleeding episodes (bloody noses, bruising, prolonged bleeding, etc.) throughout the body. Examples include haemophilia and thrombocytopaenia.
- Alport syndrome—an inherited condition associated with haematuria and protein in the urine
- Autoimmune disorders—with this group of diseases, the body's immune system mistakenly attacks and damages its own tissue and organs, including the kidneys.
Is haematuria due to cancer?
Cancers associated with the urinary tract and prostate can cause haematuria. These include:
- Bladder cancer
- Kidney cancer
- Prostate cancer
Many people with haematuria will not have any other signs or symptoms. Those who do typically have symptoms associated with the underlying condition. Some common examples include:
- Painful urination
- More frequent and/or urgent urination
- Abdominal and/or back pain
- Urinary hesitancy (interruption in flow, difficulty with urination)
- Fever (with infections)
- Tissue swelling (oedema), such as in feet, ankles, legs
- Severe pain (with kidney stones)
Testing is performed to determine the extent, severity, and persistence of haematuria and to identify and address the underlying cause. Generally, your doctor will use an initial set of tests to confirm the presence of haematuria and identify or rule out some of the more common causes. Depending on those findings, as well as the affected person's signs, symptoms, and medical history, further tests may be done.
Laboratory Tests
Initial testing:
- Urinalysis—(the dipstick test) this is typically the first test performed and the primary means by which haematuria is detected or confirmed. It consists of a visual and chemical examination that can identify gross haematuria based upon the colour of the urine and by a positive finding on a chemical test strip dipped in a urine sample. If there are abnormal findings, further tests may be performed and multiple urine samples may be tested. Other findings from a urinalysis, such as the presence of protein, may give clues to the cause.
Possible follow-up testing to evaluate health of the kidneys and their function may include:
- Urine culture—performed to exclude infection when suspected
- Urine protein or urine albumin (microalbumin)
- Blood tests for creatinine and to establish estimated glomerular filtration rate (eGFR)
- Urine cytology—performed to look for and identify abnormal cells in the urine
Other testing will be performed as guided by the signs and symptoms present e.g. PSA measurement in men to investigate the prostate gland.
Non-Laboratory Tests
To identify abnormalities, kidney damage, kidney obstructions, tumours, or cancers, imaging (in the form of ultrasound, X rays or direct inspection) may be necessary. Examples include:
- Abdominal ultrasound
- CT scan
- Cystoscopy
Frequently, no treatment is necessary for a single incident of haematuria or for haematuria that is self-limited, such as that due to strenuous exercise.
Treatments for other causes of haematuria are geared towards resolving or managing the underlying condition and treating any associated symptoms. For more on conditions that may cause haematuria and their associated treatments, see the Related Pages tab.
People who find blood in their urine should talk to their doctor about it so that the appropriate investigations can take place.