Haematuria

Macroscopic Haematuria- visible blood in the urine

Microscopic Haematuria- not visible but identified by urine microscopy or dipstick test.  This may be symptomatic or asymptomatic.  Defined as >3 red blood cells in the urine.

NB Be wary that dipsticks actually detect haem, and can (in some uncommon situations) be false negative/positive.  Also recognise that it can be normal to have asymptomatic microscopic haematuria, which usually doesn’t require investigation.

• In children and young people, glomerular causes are more predominant.  In older people, this decreases and cancer and stone disease become more common.

Assessment and Investigation

What is significant haematuria?

• Any single episode of macroscopic haematuria
• Any single episode of symptomatic microscopic haematuria in the absence of UTI and other transient causes
• Persistent asymptomatic microscopic haematuria (2 out of 3 separate urinalysis) in the absence of UTI and other transient causes
  • NB the presence of haematuria should NOT be attributed to anti-coagulant/anti-platelet therapy, unless trauma (e.g. traumatic catheterisation) is present.

Characteristics 

• A renal cause such as glomerulonephritis will generally cause persistent microscopic haematuria with or without periods of gross haematuria
• Gross haematuria associated with renal causes will usually be present throughout the stream
  • if haematuria is only present at the start of stream- it is suggestive of a distal urethral cause e.g. urethritis
  • if only present at the end- it is suggestive of upper urethral/prostatic/trigonal cause
    • this said, bladder cancer and other bladder causes can often present as gross haematuria throughout the stream

Associated symptoms

• Pain- usually associated with stone disease or infection
• Rash, arthralgia, fatigue- may be associated with an inflammatory/immune mediated cause
• Fatigue, night sweats and weight loss may be present with neoplastic causes

Investigations

• EXCLUDE UTI- Urine dipstick should always be done first
  • Nitrites and leucocyte markers suggest UTI
  • Protein suggests nephrological cause e.g. glomerulonephritis
  • MSSU should follow any abnormal dipstick to further evaluate findings
• Symptomatic microscopic haematuria and asymptomatic persistent microscopic haematuria should be further investigated:
  • Blood pressure
  • Creatinine/eGFR (renal function)
  • Urine sample for protein/creatinine ratio (normally <50) or albumin/creatinine ratio (normally (<30)
• All macroscopic haematuria should be investigated by urology with some form of imaging
  • Usually Cystoscopy + USS or CT KUB
• All patients with symptomatic haematuria (inc macroscopic haematuria) and all patients >40 years old with any significant haematuria should be referred to urology.  Referal to renal medicine should be made if eGFR/creatinine or PCR/ACR are abnormal and/or a renal cause is suspected.

Potential Causes

• Cancer:
  • Bladder (TCC, Squamous cell carcinoma); Kidney (Renal cell adenocarcinoma); Renal pelvis/ureter (TCC); prostate
• Stones (kidney/ureteric/bladder)
• Infection
  • bacterial, mycobacterial (TB), parasitic (schistosomiasis), infective urethritis
• Inflammation
  • Cyclophosphamide cystitis, interstitial cystitis
• Trauma
  • In particular catheterisation and pelvic fractures
• Renal Cystic disease
• Nephrological causes (consider particularly in children/young adults; or with accompanying significant proteinuria; blood often takes form of red cell casts)-
  • IgA Nephropathy, post-infective glomerulonephritis, membrano-proliferative glomerulonephritis, Henoch-Schonlein purpura, vasculitis, Alport’s syndrome, thin basement membrane disease, Fabry’s disease etc
• Other causes
  • Anticoagulation therapy; sickle cell/hemophilia; renal papillary necrosis

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