Sandbox:Hematuria management

Diagnosis

Urine-based tests

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.

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).

Investigation of the lower urinary tract

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

Investigation of the upper urinary tract

This is controversial for the Investigation of the upper urinary tract cause of hematuria. 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.

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

• 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.