Description

Haematuria means the presence of blood in the urine. Often the owner will notice red colour to the urine, but sometimes laboratoy analysis is needed to detect small volumes of haemorrhage which are too dilute to see in the voided urine. On rare occasions the urine is given a pink/red discolouration due to the presence of pigment alone (haemoglobinuria), and this is technically not haematuria. If bleeding is taking place examination of urine sediment will show the presence of red and white blood cells roughly in the proportions found in normal blood samples.

Blood can enter the urine at any level of the urinary tract or from the reproductive system where they are in close contact. Examples - blood in the urine can originate from :

the kidney (e.g. idiopathic renal haemorrhage)

the ureters (inflammation, trauma)

the urinary bladder - inflammation or infection (cystitis) , the presence of stones (uroliths) causing trauma to the wall, the presence of an ulcerated cancer (e.g. transition cell carcinoma)

the urethra - inflammation (urethritis) or damage (uroliths)

the external genitalia or reproductive tract - the prostate, penis and prepuce in the male; uterus, vagina or vulva in the female.

Causes

The causes of haematuria are typically one of the following :

Trauma - direct injury, urinary calculi

Severe inflammation - bacterial infection, leptospirosis, drugs e.g. following use of the anticancer drug cyclophosphamide, Cancer benign polyps - rarely haemorrhage, and transition cell carcinomas

Haematological disorders - e.g. clotting defects

Glomerular diseases - allow red cells to pass through from the kidney's glomerular capillaries into the urine e.g. systemic lupus erythematosis and amyloidosis.

Acute tubular necrosis (acute renal failure)

Idiopathic renal haemorrhage

 

And rarely due to :

Telangiectasia (inherited renal defect)

Parasites in the kidney- dioctophyma renale or dirofilaria immitis (not seen in the UK, except imported animals)

Cystic kidneys

Radiation injury

Diagnosis

Urinalysis

Xrays - contrast studies in some cases

Blood haematology/serology

Treatment

Treat underlying cause

Last updated : October 2013