What is Haematuria?
Haematuria is a common condition characterised by blood in the urine. Haematuria is usually categorised into macroscopic, where the urine is discoloured, and microscopic, where blood is found only on a dipstick or microscopic examination. Further clinically relevant distinctions can be made between painful and painless haematuria, and haematuria of glomerular and post-glomerular origin.
Causes of Haematuria
Haematuria can originate from the kidney itself due to inflammation in the kidney, e.g. glomerulonephritis, affecting the filtering units (glomeruli). When this is the cause of haematuria, there are often other signs of kidney disease such as protein in urine, high blood pressure or abnormal renal function.
Kidney cysts, tumours or kidney stones can also cause haematuria. Blockages or stones in the ureter (tube to the bladder) may cause haematuria. The bladder may also be the cause of haematuria, in cystitis (bladder infection), stones or tumours.
Diagnosis of Haematuria
Haematuria can be diagnosed by:
- General physical examination, which includes blood pressure, pulse, prostate in a male and the gynaecological organs in a female
- Urinalysis: A midstream specimen of urine for microscopic red blood cells, white blood cells and bacteria. The presence of any crystals, ova or parasites should be noted and culture of urine specimen. The level of protein in the urine will be assessed.
- Blood tests: All patients should have a full blood count with an erythrocyte sedimentation rate. Serum urea, creatinine and electrolytes should be measured, along with albumin, calcium and liver function tests if you are unwell or in renal failure.
- CT scan
- Flexible cystoscopy involves the insertion of a lighted long tube with a camera through the urethra to inspect your bladder.
- Transurethral biopsy involves the removal of a part of tissue for examination in the lab.
Treatment of Haematuria
Treatment depends on management of the underlying condition. Some of the conditions associated with haematuria are described below:
The commonest primary renal tumour is renal cell carcinoma, an adenocarcinoma of collecting tubule origin. It commonly presents with haematuria although most are nowadays picked up incidentally by ultrasound scanning. Diagnosis is made by CT scanning and treatment is by surgical excision. Small tumours may now be treated by local excision with preservation of kidney function.
Transitional cell carcinoma of the renal collecting system usually causes haematuria. Diagnosis may be difficult, requiring retrograde imaging and ureteroscopy. Treatment is by either local excision or, for high grade or larger lesions, nephroureterectomy. Immunotherapy is used for metastases with limited success; radiotherapy has little place except for palliation of bone metastases.
Benign renal tumours may cause both bleeding and diagnostic difficulty. They are rare, with the exception of the incidental and usually asymptomatic renal cyst. Angiomyolipoma is a hamartomatous lesion, which may grow to great sizes and be associated with major haemorrhage. Treatment is again surgical, conserving normal renal tissue where possible.
Stone disease is very common, with concretions forming in the renal papillae, which then form a nidus for stone formation in the collecting system. While most stones may cause infection, one particular type (infection or matrix stone) is thought to be caused by bacteria that are able to split urea to form ammonium. Renal stones tend to be asymptomatic but may cause haematuria by either infection or direct irritation of the mucosa. They may also cause renal pain if large enough or obstructing. Diagnosis is by imaging, usually intravenous urography. Renal stones can usually be treated by extracorporeal shock wave lithotripsy on an outpatient basis, although large or complex stones may need percutaneous or open surgical removal.
Glomerulonephritis tends to present with microscopic haematuria. While pain may be associated, most cases will have either no symptoms or may show signs of renal failure. Investigation is as outlined above.
Pyelonephritis (ascending urinary tract infection)
Acute bacterial pyelonephritis results from bacteria ascending from the bladder, either by direct spread (vesico-ureteric reflux) or per ureteric lymphatic extension. Painless haematuria may occur, but the symptom complex usually includes loin pain, fever and possibly septicaemia.
This condition occurs in diabetics and those with deficiency of oxygenation, particularly sickle cell disease. It is characterised by a radiolucent filling defect on IVU and may usually be treated expectantly.
Stones may form in the kidney and drop into the tube to the bladder (the ureter). They usually present with pain but may have haematuria as the only symptom. The presence or absence of obstruction and the size of the stone dictates management. Most ureteric stones will pass on their own, but sometimes treatment by passing a telescope up to the stone to remove it is required.
Typically, cystitis is painful and in men is commonly associated with bladder outflow obstruction. Schistosomiasis and drug-related cystitis are rarer causes of bladder inflammation causing bleeding. Diagnosis is by urine microscopy and culture, assisted by cystoscopy and biopsy if necessary.
Most of the interest in painless haematuria stems from the desire to diagnose bladder tumours at an early stage. Nearly all are transitional cell cancers, with smoking and aromatic hydrocarbon exposure being risk factors. Rarer bladder tumours include adenocarcinoma (usually arising from the urachus) and squamous cancer (associated with chronic inflammation and schistosomiasis). Diagnosis is as outlined above, with management depending on the stage and grade: 70% are superficial at presentation and are managed by transurethral surgery with or without the use of intravesical therapy. For invasive tumours the choice lies between radical cystectomy and radiotherapy. Metastatic disease may respond to platinum-based chemotherapy.
Rare causes of haematuria
Arteriovenous malformations, tuberculosis and arteritis may all cause haematuria. Patients on anticoagulants whose control is in the normal therapeutic range and who have haematuria must be fully investigated as above, since haematuria is not a normal consequence of anticoagulation.