Hematuria management

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History and Symptoms | Physical Examination | Laboratory Findings | Electrocardiogram | Chest X Ray | CT | MRI | Echocardiography or Ultrasound | Other Imaging Findings | Other Diagnostic Studies

Diagnosis[edit | edit source]

Evaluation of patients with hematuria includes a focused history and physical examination, urinalysis and various blood tests. evaluation of hematuria is best performed in stepwise progression, beginning with simple and noninvasive investigations, followed by more aggressive interventions if positive results are obtained. Most importantly the lower urinary tract should be visualized using cystoscopy, usually using a flexible scope, and the upper tract imaged by a combination of modalities including plain X-ray, ultrasonography, intravenous urography or CT urography.

Urine-based tests[edit | edit source]

A fresh sample of urine should be dipstick tested for proteinuria (renal disease) or nitrituria (infection). If abnormal the sample should be sent for microbiological assessment (microscopy and culture) and cytology.[1]

Dipstick test[edit | edit source]

A urine dipstick analysis is a highly sensitive measure for detection of blood, but it lacks specificity (sensitivity of 95% and a specificity of 75%). This translates into a large number of false positives, in which case, the urine dipstick is positive, but microscopy reveals fewer than 3RBC/HPF. This particular combination can be seen in the following benign or pathological circumstances:[2]

  1. Ingestion of certain foods: beets, blackberries, food coloring
  2. Ingestion of certain medications: Chloroquine, Ibuprofen, Iron, Sorbitol, Nitrofurantoin, Phenazopyridine, Urates or Rifampin (which often produces orange urine)
  3. Hemoglobinuria: often in the setting of hemolytic anemia
  4. Myoglobinuria: related to muscle damage (rhabdomyolysis), often after vigorous exercise or trauma
  5. Urinary tract infection: secondary to the action of bacterial peroxidases on the dipstick
  6. Delay in reading urine dipstick after submersion in urine
  7. presence of semen in urine.

Given the large number of situations in which a positive dipstick may not represent true hematuria, all urine samples that test positive on dipstick analysis must be sent for microscopy to confirm hematuria.

Microscopy Urine cytology

Microscopy is performed on urinary sediment (following centrifuging a fresh urine sample) and can quantify the number of erythrocytes.

Advantages

  • Useful for detecting urinary casts (suggesting renal disease)
  • Useful for detecting urinary crystals (suggesting calculous disease)
  • Useful for detecting dysmorphology of red cells (suggesting a glomerular cause of hematuria)
  • Useful for detecting atypical or malignant epithelial cells from a tumour are shed into the urine.

Urine cytology is the ‘gold standard’ urine-based test for detecting cancer.

Advantages

  • Cytology is best at detecting poorly differentiated tumours and carcinoma in-situ (with poorly-adhesive grossly abnormal cells). But it has a low sensitivity and specificity for low-grade tumours (that have normal looking adherent cells).

Blood tests[edit | edit source]

  • Complete blood count (detects anaemia)
  • Coagulation studies (to detect hemoglobinopathies)
  • Complement levels ( to detect Nephritic cause of hematuria)
  • Serum urea, creatinine and electrolytes (to detect renal impairment)

Investigation of the lower urinary tract[edit | edit source]

Cytoscopy: Flexible cystoscope is useful for the inspection of the urethra and visualization of the bladder mucosa. It is quick, well tolerated and safe procedure. The detection of an abnormality will require subsequent rigid cystoscopy under anaesthesia, whereby tissue can be obtained or treatment performed.[1]

Investigation of the upper urinary tract[edit | edit source]

Evaluation of the upper urinary tract is more complex, and requires a balance between the low detection rate of pathology and the number or extent of tests required to visualize the urinary organs. No single imaging modality has the desired attributes of a high sensitivity and specificity, safety (low radiation exposure), low cost and applicability to lots of patients.[1]

Ultrasound (USS) Intravenous urography (IVU) Computed tomography (CT) Endoscopy/Fluoroscopy MRI

Advantages

  • Ultrasound of the abdomen and pelvis is safe.
  • It is good at detecting
    • Detecting renal parenchymal lesions (e.g. renal cell carcinoma)
    • For characterizing renal cysts
    • Showing renal calculi
    • For determining ureteric obstruction (Hydronephrosis)

Disadvantages

  • USS is poor at detecting small lesions within the collecting system (e.g. UCC of the renal pelvis)

Advantages

  • IVU is good at detecting abnormalities of the urothelium (UCC of the ureter and renal pelvis) and stones.

Disadvantages

  • Poor at detecting small renal parenchymal lesions that do not distort the renal outline.
  • It cannot distinguish cystic from solid masses.

Advantages

  • Distinguish equivocal cases, for planning treatment options and determining the nature of small renal parenchymal lesions.
  • Has a high specificity and sensitivity for investigating the causes of hematuria.

Disadvantages

  • CT is expensive, time consuming and carries a high radiation exposure.

Advantages

  • Used to investigate intravenous urography filling defects and to treat stones.
  • In patient with continued undiagnosed hematuria, this can be used to collect urine or brushings from each ureter, allowing cytology to determine the site of bleeding and the presence of very small tumors of carcinoma in-situ.

Disadvantages

  • Requires general anaesthesia for the procedure.

MRI can been used for equivocal cases and planning treatment.

The gold standard investigation protocol for upper urinary tract would combine USS and IVU to evaluate the upper urinary tract. However, an IVU has a large radiation dosage with a small risk of reaction to contrast medium and detects upper tract UCC which are rare (less than 1% of all tumors presenting with hematuria). If looking for stone disease USS and a plain radiograph of the abdomen is recommended and IVU is reserved for equivocal cases, patients with persistent hematuria or patients with a high risk of UCC (elderly, smokers, occupational exposure).

Investigation of a nephrological cause of hematuria[edit | edit source]

  • 24-hours urine collection should also be obtained to assess kidney function (e.g. Creatinine clearance/glomerular filtration rate, urine osmolality, sodium and albumin concentrations).
  • Renal biopsy

The initial evaluation of patients presenting with gross hematuria is 3-fold:[3]

  • Assess hemodynamic stability
  • Determine the underlying cause of hematuria
  • Ensure urinary drainage.

Evaluation of patients with haematuria includes a focussed history and physical examination, urinalysis and various blood tests.Most importantly the lower urinary tract should be visualized using cystoscopy, usually using a flexible scope, and the upper tract imaged by a combination of modalities including plain X-ray, ultrasonography, intravenous urography or computed tomography urography.

The treatment options for haematuria depend on the underlying cause.

Hematuria ' One-Stop ' Clinic[edit | edit source]

In recent years the ‘one-stop’ hematuria clinic has become popular for the investigation of hematuria as this enables synchronous urological and radiological evaluation of the patient, resulting in rapid diagnosis and treatment.This clinic has been set up to save you having repeated visits to the hospital. For most patients, in the course of one visit, all the tests needed to diagnose the cause of the blood in the urine will be undertaken. Occasionally some further tests will be necessary as a result of the findings at the first visit. In the morning you will have either an x-ray or a scan (KUB or Ultrasound) depending on the type of bleeding you have experienced. Early in the afternoon you will be seen by the consultant urologist or one of his team. You will then be examined and finally an internal inspection of your bladder will be performed. By the end of your visit you should know the outcome of all your tests and whether anything further needs to be done.[4]

References[edit | edit source]

  1. 1.0 1.1 1.2 "www.surgeryjournal.co.uk".
  2. Amin, Nimisha; Zaritsky, Joshua J. (2011). "Hematuria": 258–261. doi:10.1016/B978-0-323-05405-8.00069-3.
  3. Avellino GJ, Bose S, Wang DS (2016). "Diagnosis and Management of Hematuria". Surg Clin North Am. 96 (3): 503–15. doi:10.1016/j.suc.2016.02.007. PMID 27261791.
  4. Ooi WL, Lee F, Wallace DM, Hayne D (2011) 'One stop' haematuria clinic in Fremantle Hospital, Western Australia: a report of the first 500 patients. BJU Int 108 Suppl 2 ():62-6. DOI:10.1111/j.1464-410X.2011.10711.x PMID: 22085132

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