Blood in Urine (Haematuria) — Causes, Diagnosis & Treatment Guide — Symptoms, Causes & Treatment | MyMedicPlus

Haematuria — the presence of blood in the urine — is defined as visible haematuria (VH, also known as frank or gross haematuria — urine visibly red, pink, or brown) or non-visible haematuria (NVH, also known as microscopic haematuria — more than 10 red blood cells per microlitre on microscopy, or 2+ or above on urine dipstick, not explained by another cause). Haematuria is always an abnormal finding in adults (except in women during menstruation — urine should be re-tested). It should never be dismissed or attributed to benign causes without appropriate investigation. Bladder cancer is diagnosed in 5-15% of patients with visible haematuria and approximately 2% of those with non-visible haematuria. In the UK, NICE recommends urgent referral on the 2-week-wait (2WW) cancer pathway for all patients aged 45 or over with unexplained visible haematuria, or NVH plus significant risk factors (smoking history, age over 60, occupational exposure). Other common causes include urinary tract infection (UTI), kidney stones, benign prostatic hyperplasia (BPH), glomerulonephritis, and anticoagulant therapy.

Causes are divided by anatomical origin: urological (from the kidneys, ureters, bladder, prostate, or urethra) or medical (glomerular/systemic). Common urological causes: urinary tract infection (UTI) — most common cause of haematuria in young women; bacterial cystitis from E. coli (80% of UTIs); bleeding typically associated with dysuria, frequency, and urgency; diagnosed by MSU (mid-stream urine) culture; kidney stones (urolithiasis) — calcium oxalate, uric acid, or struvite stones; typically associated with acute flank or colicky pain radiating to groin (renal colic); diagnosed by CT KUB (unenhanced); haematuria often transient; bladder cancer — the most important diagnosis not to miss; primarily urothelial (transitional cell carcinoma — TCC); risk factors: smoking (the single most important modifiable risk factor — smokers have 2-3x increased risk), male sex (3:1 vs. females), age over 55, occupational exposure (aromatic amines — chemical, rubber, and dye industries), cyclophosphamide treatment, chronic urinary tract inflammation (bladder stones, schistosomiasis); benign prostatic hyperplasia (BPH): in older men — bleeding from enlarged prostate gland; prostate cancer: typically associated with elevated PSA; urothelial carcinoma of the renal pelvis/ureter: rare but requires full upper tract assessment; renal cell carcinoma (RCC — 'internist's tumour' — classic triad of haematuria, loin pain, and mass in only 10%); transitional cell carcinoma of the bladder (most common urinary malignancy); urethritis/urethral pathology. Medical (glomerular) causes: IgA nephropathy (Berger's disease — most common glomerulonephritis worldwide; episodic macrohaematuria coinciding with URTI; microscopic haematuria between episodes); thin basement membrane disease (benign hereditary nephritis — isolated NVH, normal renal function — often a benign finding); Alport syndrome (hereditary nephritis — X-linked, progressive renal failure + deafness + ocular abnormalities); post-streptococcal glomerulonephritis; lupus nephritis; ANCA-associated vasculitis (GPA, MPA); endometriosis (cyclical haematuria in women). Other causes: anticoagulant therapy (warfarin, DOACs — bleeding unmasking underlying pathology rather than causative; investigation still required); exercise-induced haematuria (after strenuous exercise — usually resolves with rest); trauma; schistosomiasis (Schistosoma haematobium — bladder infection causing painless haematuria in travellers returning from endemic areas).

Visible haematuria (VH): urine is visibly red, pink, brown, or cola-coloured; often alarming to the patient; amount of blood visible does not correlate with severity of underlying cause — a small tumour can cause substantial VH; clots in urine — 'clot colic' (blood clots causing ureteric or urethral obstruction — extremely painful). Non-visible haematuria (NVH): asymptomatic — detected incidentally on urine dipstick (occupational screening, insurance medical, health check) or during investigation for UTI or other urinary symptoms. Associated symptoms that may indicate specific causes: dysuria, frequency, urgency, suprapubic pain — UTI or bladder tumour (irritative LUTS); flank or loin pain radiating to groin (renal colic from kidney stone); frequency, nocturia, hesitancy, poor stream, terminal dribbling (BPH); painless visible haematuria in an older man or smoker — bladder cancer until proven otherwise; fever + rigors + flank pain — pyelonephritis; generalised oedema, hypertension, reduced urine output — glomerulonephritis (nephritic syndrome); weight loss, anorexia, loin mass — renal cell carcinoma; cyclical haematuria in women — endometriosis. Important: painless haematuria in any adult should always be investigated — it does not exclude malignancy.

Urine dipstick: quick screening test for haematuria — positive if 1+ or above (detects haemoglobin, not necessarily intact red cells); note: false positives from myoglobinuria, dehydration, beetroot, rifampicin, Lycopene. Mid-stream urine (MSU) microscopy and culture: confirms haematuria (10+ red blood cells/hpf) and excludes infection (pyuria and positive culture in UTI); casts on microscopy (red cell casts — pathognomonic for glomerulonephritis). Urine cytology: detects shed malignant cells; sensitivity limited for low-grade bladder tumours; specific for high-grade TCC; less useful as primary investigation with flexible cystoscopy available. Renal function tests (U&E, eGFR) and urinalysis for proteinuria (ACR): assess for nephropathy; proteinuria + haematuria suggests glomerular disease. PSA (prostate specific antigen): for men over 40 with NVH or urinary symptoms. CT urography (CTU) — the first-line imaging investigation: combined arterial and delayed phase images visualise kidneys, ureters, and bladder; detects renal masses, urothelial tumours, upper tract TCC, and stones; sensitivity for bladder tumours above 5 mm: 90%+. CT KUB (unenhanced): for suspected renal colic — highly sensitive for stones (above 3 mm). Renal ultrasound: useful for cystic vs. solid renal lesion characterisation, hydronephrosis detection; lower sensitivity for upper tract TCC and bladder tumours versus CT; used in young patients and pregnant women to avoid radiation. Flexible cystoscopy (outpatient, under local anaesthetic): direct visualisation of bladder mucosa — gold standard for bladder tumour detection; biopsies taken under rigid cystoscopy with TURBT (transurethral resection of bladder tumour). NICE 2WW referral criteria (suspected cancer pathway): all adults aged 45+ with unexplained visible haematuria; adults aged 60+ with NVH; adults under 60 with NVH plus one of: UTI or raised PSA. Renal biopsy: for suspected glomerulonephritis (proteinuria + haematuria + renal impairment) — diagnosis and guides treatment.

Treatment is determined entirely by the underlying cause. UTI: oral antibiotics according to local sensitivity (nitrofurantoin 100 mg MR BD for 5 days or trimethoprim 200 mg BD for 7 days — NICE CKS); IV antibiotics for complicated UTI or pyelonephritis; haematuria resolves with treatment. Kidney stones: renal colic — analgesia (IV/IM diclofenac 75 mg or IV morphine if contraindicated); alpha-blockers (tamsulosin 400 mcg) for ureteric stones below 10 mm — facilitates spontaneous passage; stones below 5 mm: 95% pass spontaneously; above 10 mm: usually require intervention — extracorporeal shockwave lithotripsy (ESWL), flexible ureterorenoscopy + laser (fURS), or percutaneous nephrolithotomy (PCNL). Bladder cancer: non-muscle invasive bladder cancer (NMIBC — stages Ta, T1, CIS): transurethral resection of bladder tumour (TURBT) for initial diagnosis and treatment; intravesical BCG immunotherapy (4 installations + 1-3 year maintenance) for high-risk NMIBC — reduces recurrence by 30-40% and progression; intravesical mitomycin C for low/intermediate risk; regular surveillance cystoscopy (every 3 months for 2 years, then annually for 5+ years); muscle-invasive bladder cancer (MIBC — T2+): neoadjuvant cisplatin-based chemotherapy + radical cystectomy (removal of bladder + urinary diversion) — potentially curative; radical radiotherapy for fit patients not suitable for surgery. Renal cell carcinoma: surgical nephrectomy (laparoscopic or open) — curative in localised disease; targeted therapies (sunitinib, pazopanib) and immunotherapy (nivolumab + ipilimumab — CheckMate 214) for metastatic disease. IgA nephropathy: ACEi or ARB for proteinuria and BP control; SGLT2 inhibitors (dapagliflozin, empagliflozin) — emerging evidence; targeted-release budesonide (Nefecon — NICE approved 2022); for high-risk progressive IgA nephropathy — hydroxychloroquine. Glomerulonephritis: specific immunosuppression based on type (mycophenolate + steroids for lupus nephritis; cyclophosphamide for ANCA vasculitis). BPH: alpha-blockers (tamsulosin) for LUTS; 5-alpha reductase inhibitors (finasteride, dutasteride) for prostate reduction; surgical TURP for refractory cases.

Delayed bladder cancer diagnosis (the most important preventable harm — if haematuria is dismissed, attributed incorrectly to UTI alone without investigation, or not referred appropriately, bladder cancer progresses from curable non-muscle-invasive to metastatic disease; 5-year survival falls from above 90% for T1 disease to approximately 30% for metastatic disease). Clot retention (severe haematuria with large clot burden obstructs the urethra or bladder neck — causing acute painful urinary retention requiring three-way catheter irrigation and emergency cystoscopy for haemostasis). Anaemia from chronic blood loss (chronic haematuria from bladder cancer, renal cell carcinoma, or renal calculi causes progressive iron-deficiency anaemia — requiring transfusion and urgent treatment of the underlying cause). End-stage renal disease (untreated glomerulonephritis — IgA nephropathy, ANCA vasculitis, Goodpasture's syndrome — causes progressive renal scarring and eventual renal failure requiring dialysis or transplantation). Urosepsis (obstructed infected urinary tract — including an infected obstructed kidney from stone disease — is the most life-threatening acute complication, with mortality above 20% in severe cases without emergency decompression and IV antibiotics).

Bladder cancer prevention: smoking cessation — the single most impactful intervention (reduces bladder cancer risk by 50% within 10 years of stopping); avoid occupational carcinogen exposure (aromatic amines in rubber, chemical, and dye industries — appropriate protective equipment; follow health and safety regulations; occupational surveillance). Urinary tract infection prevention: adequate hydration (2 litres water/day); void after sexual intercourse; avoid urinary catheter use where possible; cranberry products (modest evidence — meta-analyses suggest some benefit for recurrent UTI prevention). Kidney stone prevention: adequate fluid intake (aim for urine output above 2 litres/day); reduce sodium intake (calcium oxalate stones); restrict oxalate-rich foods if calcium oxalate stones; allopurinol for uric acid stones; thiazide diuretic for recalcium hypercalciuria; stone analysis and 24-hour urine collection guides specific dietary and drug prevention. Glomerulonephritis: treat streptococcal throat infections promptly; optimal BP control and ACEi/ARB for proteinuric renal disease to slow progression.

Attend Emergency Department immediately for: urinary retention with inability to pass urine and severe lower abdominal pain — may be from blood clots obstructing the urethra; massive visible haematuria with haemodynamic compromise (dizziness, rapid pulse, pale skin); severe renal colic with fever and rigors — infected obstructing ureteric stone — emergency urological decompression required. Contact GP or attend walk-in centre urgently for: any episode of visible haematuria in an adult — requires urgent investigation (NICE 2WW referral if aged 45+, or any age if risk factors); haematuria with bone pain, unexplained weight loss, or a palpable loin mass — urgent urological assessment; haematuria in a traveller returning from sub-Saharan Africa or Middle East — possible schistosomiasis; haematuria on anticoagulants — investigation still required (anticoagulation does not cause haematuria — it may reveal underlying pathology). Do not assume haematuria is due to a UTI without microbiological confirmation — painless haematuria especially in smokers must be investigated for bladder cancer even when a UTI is also present.