Haematuria is the name given to the presence of blood in the urine. It can be identified by its reddish colour (macroscopic haematuria) or it can only be visible under a microscope or identified in laboratory urine tests (microscopic haematuria)....CONTINUE READING
According to experts at Healthline, WebMD – These urine tests can identify the presence of erythrocytes (red blood cells) and should be considered positive if more than 3 red blood cells are found per high magnification field.
Haematuria can be due to several causes. Some causes may affect both sexes (e.g. urinary infection). In other cases it may affect only one sex. Haematuria in men may be related to pathologies related to the urinary / reproductive tract, exclusive to men (e.g. prostatitis). In turn, some pathologies may be exclusive to women (e.g. endometriosis). See more information in “causes for haematuria”.
Haematuria should always be investigated and is usually a sign of a more or less serious underlying pathology (disease), as we will discuss below. Haematuria can be asymptomatic (without other symptoms) or be accompanied by other signs or symptoms such as pain, fever, among others. See related symptoms in each of the causes for haematuria.
Haematuria is often detected in routine analyses or appears in the context of investigation of lower urinary tract symptoms. In any case, the doctor should always investigate the causes in order to institute treatment as early as possible. See more information in Diagnosis and treatment of haematuria.
Causes of haematuria
Below we have listed some of the most common causes that affect both sexes or are unique to one sex only.
1) Urinary infection
Urinary infection causes inflammation of the urinary tract and, in serious cases, may cause the presence of blood in the urine (microscopic or macroscopic).
The most common symptoms are: pain when urinating, sudden urge to urinate, false urge, increase in urinary frequency, fever, etc.
2. Urinary tract tumors
Tumours of the urinary tract (kidney, ureter, bladder, prostate or urethra) can cause the presence of blood in urine. In early stages there might not be any other associated symptoms; in more advanced cases they can cause several different symptoms, varying according to the location of the tumour: for example tumours of the kidney and ureter can cause unilateral back pain, fever and weight loss; tumours of the bladder or urethra can cause irritative symptoms such as urgency, increased frequency of urination or false urges, etc.
3. Benign prostatic hypertrophy
The increase in prostatic volume generally causes an increase in vascularisation. Gradually, this increase in vascularisation increases the probability of bleeding from the prostate, which is more likely the larger the prostate is.
The most common symptoms are: difficulty in urinating, effort to urinate, weak urine stream, incomplete emptying sensation, among others.
4. Inflammation of the bladder (cystitis)
All medical conditions which cause inflammation of the bladder may cause blood to appear in the urine. These conditions may be related to: a history of radiotherapy (radica cystitis), chronic inflammation of the bladder (chronic/interstitial cystitis), chemical cystitis (some chemical agents used for treating other diseases may cause bladder inflammation and haematuria), etc.
5. Urinary calculi / lithiasis
The presence of lithiasis (“stones”) in the urinary tract, especially if voluminous, can cause bleeding. This may occur in the context of damage to the mucous membrane when the stone moves or simply because of the irritation and inflammation it causes.
In most cases, urinary calculi do not cause great symptoms; when they move and cause urinary tract obstruction or relevant inflammation, the appearance of pain, macroscopic haematuria, irritative symptoms of the urinary tract, etc., is common.
6. Urogenital trauma
In situations of traumatic injuries on the urinary tract, the presence of blood in the urine may appear. This is most common in road accidents, contact sports, falls with trauma of the perineum, etc.
The associated symptoms are generally related to the trauma itself. All situations of trauma which cause the appearance of haematuria should be evaluated in a hospital setting as soon as possible.
7. Nephrological / glomerular / interstitial tubule causes
The kidney is responsible for filtering harmful substances from the blood. But sometimes this filtering system may not be working properly and red blood cells can also pass into the urine.
Usually, in these cases, the red blood cells take characteristic forms (dysmorphic, cylinders, etc.) and other changes in the characteristics and properties of the urine may appear (e.g. presence of excess protein, etc.).
8. Vascular malformations
In 75% of the cases, vascular malformations are acquired after surgery, biopsy or trauma. These malformations may cause symptoms other than the presence of blood in the urine such as pain, hypertension, etc.
9. Other causes for haematuria
Apart from the pathologies (diseases) listed above which are among the main ones for haematuria, there may be others, as described below:
Endometriosis in the urinary tract;
Uretero-iliac fistula;
Alterations in blood clotting or taking anticoagulants;
Nutcracker syndrome;
Stress haematuria;
Benign essential haematuria.
Some substances can cause abnormal urine colouring, which does not correspond to blood in the urine although it may appear to be. These include some drugs and foods such as: Blueberries, Beetroot, Blackberries, Paprika, Broad beans, Artificial food colours such as Rifampicin, Sulphonamides, Phenytoin, Phenolphthalein, Chloroquine, Levodopa, Adriamycin, Nitrofurantoin, Metronidazole, Quinine.
Diagnosis of haematuria
In the presence of the signs or symptoms described above, the patient should seek a urologist (urology specialist) for evaluation and diagnosis of the underlying pathology.
In the initial evaluation of haematuria, it is common to repeat urine tests, which may include 24-hour urine analysis. Depending on the type of haematuria, associated symptoms and risk factors of the patient, the remainder of the study will include:
– Urethrocystoscopy: study performed in an outpatient clinic where, under vision, the urethra and bladder are observed and which allows the collection of fluid for cytological study or even tissue for anatomo-pathological analysis.
-Urinary cytology – analysis under a microscope of the cells present in urine. This exam is useful in the evaluation of possible aggressive tumours of the urothelium (layer that lines the urethra, bladder, ureters and the renal excreta)
– Ultrasound of the bladder, prostate and kidneys: imaging study that allows the evaluation of gross alterations of the bladder kidney and evaluation of the prostate volumetry. It can help in the diagnosis of lithiasis/urinary calculi, kidney cysts and tumours, bladder tumours, urinary tract obstruction, etc.
– Computed tomography (CT or CAT): more detailed imaging study which helps diagnose most of the causes of haematuria. Besides the greater sensitivity and specificity compared to ultrasound, it also allows the ureters to be studied in greater detail. The main disadvantages are the greater amount of radiation, the need to administer contrast and the associated cost.
– Magnetic Resonance Imaging (MRI): used in situations in which it is not possible to perform CT or to clarify diagnostic doubts in CT (only for specific cases). Find out here what MRI is.
Treatment of haematuria
The treatment of haematuria depends on the underlying cause (which pathology or disease is causing the presence of blood in the urine).
The general advice to prevent clotting and try to minimise the effects of haematuria is to strengthen oral hydration.
In some cases, it may be advisable to take certain drugs which promote clotting and which can limit the duration of haematuria, and to use analgesic/anti-inflammatory medication to reduce the pain.
In any case, it is essential to consult your doctor to study the cause and therapeutic orientation towards it.
In serious cases of haematuria, namely when it is macroscopic and prolonged in time and/or associated with clots, it is necessary to be evaluated in the Emergency Department. Blood tests allow the assessment of haemoglobin values and the diagnosis of anaemia to determine the need for blood transfusion.