Haematuria may be caused by pathology of any part of the urinary tract. Blood may make the urine red or dark brown. Dipstick tests are very sensitive, identifying much smaller quantities of blood than can be seen with the naked eye.
Causes of haematuria
- dyes in food/medicines can cause red urine (dipstick testing negative)
- strenuous exercise may cause transient haematuria – OK, this is real haematuria, but not as we know it (Jim)
- Urinary tract infections (UTI)
- Schistosomiasis (in affected regions of the world, or those who’ve visited)
- Renal stones
- Tumours of the bladder or collecting system
- Kidney tumours and cysts
- Prostate gland disease
- Glomerulonephritis (proteinuria, hypertension and abnormal kidney function may also be present)
- Dipstick test for urinary protein, consider testing for albumin
- Urine microscopy and culture (or FACS analysis)
- Blood pressure measurement
- Blood tests for renal function, blood count
- Ultrasound scan of kidneys and urinary tract
- Intravenous urogram if high risk of lesion in ureters/ collecting system (e.g. macroscopic haematuria, or risk factors present)
Renal pathway (for glomerulonephritis etc) – favour in younger patients, and consider if there are any or many of:
- Renal impairment (without urinary symptoms to suggest obstruction)
A past history or family history of renal disease may also influence you. Macroscopic haematuria may occur, almost always in the presence of one or more of the three features above, but in general is more likely from urological causes. Renal biopsy may be indicated. Microscopic haematuria alone carries a low but not zero risk of significant underlying renal disease and some may prefer a renal biopsy in these circumstances.
If all investigations are negative
If no cause is found and haematuria continues, regular monitoring (usually every 6 extending to 24 months) of urine protein, blood pressure and serum creatinine is all that is required. Reconsider if anything changes.