|Red flag symptoms|
Macroscopic or visible haematuria (VH) may be obvious, or the urine may look like cola in acute glomerulonephritis.
It is worth considering rarer causes of red/pink urine, such as myoglobinuria, beeturia and discoloration secondary to drugs such as rifampicin.
Microscopic or non-visible haematuria (NVH) may be detected on urinary dipstick. A reading of 1+ or more is considered significant. Trace haematuria is considered negative.
Persistent haematuria may be defined by having two out of three dipsticks positive for blood. Assessment and further investigation may be necessary to rule out malignancy or underlying renal pathology.
History and examination
NVH can be symptomatic and may present with lower urinary tract symptoms. Urinary frequency, urgency, dysuria and hesitancy, as well as abdominal/pelvic pain, may be elicited in the history.
Systemic enquiry may include rashes and joint pains. Travel history and occupation may be relevant.
Haematuria may often occur in the presence of a UTI; it is recommended to repeat dipstick testing after treatment to ensure it was transient. Menstruation and exercise-induced haematuria are other transient causes.
It is important not to attribute haematuria to anticoagulant therapy, because these medications are not causative.
Physical examination should include BP and abdominal check.
UTI should be excluded. U&Es may be necessary and protein:creatinine ratio or albumin:creatinine ratio should be measured.
If there is evidence of a decline in eGFR or there is already evidence of stage 4/5 chronic kidney disease, and a urological cause of haematuria has been excluded, a renal opinion is recommended.
In hypertensive patients aged <40 years, significant proteinuria, haematuria and VH in the presence of intercurrent infection may necessitate a renal referral. Patients aged <50 years with microscopic haematuria with proteinuria or raised serum creatinine should be referred to a renal physician; otherwise, a non-urgent referral to urology should be made.
Long-term monitoring is advisable in patients who have been referred and have negative investigations. This includes being vigilant for urinary symptoms and VH, and detecting increasing or significant haematuria, deteriorating renal function and hypertension.
- Dr Kochhar is a GP principal in St Leonards, East Sussex
- NICE. Referral guidelines for suspected cancer. June 2005.
- Renal Association and British Association of Urological Surgeons. Joint Consensus Statement on the Initial Assessment of Haematuria. July 2008.