Hematuria laboratory findings
|
Hematuria Microchapters |
|
Diagnosis |
|---|
|
Treatment |
|
Case Studies |
|
Hematuria laboratory findings On the Web |
|
American Roentgen Ray Society Images of Hematuria laboratory findings |
|
Risk calculators and risk factors for Hematuria laboratory findings |
Steven C. Campbell, M.D., Ph.D. Associate Editor(s)-in-Chief: Venkata Sivakrishna Kumar Pulivarthi M.B.B.S [1]
Overview
Often, the diagnosis is made on the basis of the medical history and urine and blood tests—especially in young people in whom the risk of malignancy is negligible and the symptoms are generally self-limited.
Urinalysis[1]
Urinalysis is a simple and efficient tool to diagnose renal and urological diseases. Typically, the urine dipstick test for blood initially identifies patients with microscopic hematuria. The urine microscopic evaluation not only confirms hematuria but also helps differentiate glomerular from nonglomerular sources of bleeding. In glomerular hematuria, the RBCs are exposed to large changes in pH and osmotic pressure as they go through the renal tubules, making them dysmorphic. In nonglomerular hematuria, the RBCs tend to be homogeneous and normal in shape. The presence of proteinuria of 2+ or greater by dipstick also suggests glomerular hematuria, because hematuria alone does not result in such a large protein excretion. Blood clots do not occur in glomerular hematuria, because of the presence of urokinase and tissue-type plasminogen activators in the glomerular filtrate. RBC casts are virtually pathognomonic for glomerular hematuria, because the matrix of the cast is Tamms-Horsfall protein, which is secreted by the distal tubule.
Microscopy findings[2]
- Positive for urinary casts (suggesting renal disease)
- Positive for urinary crystals (suggesting calculous disease)
- Positive for dysmorphology of red cells (suggesting a glomerular cause of hematuria)
- Positive for atypical or malignant epithelial cells from a tumour are shed into the urine.
- In glomerular hematuria
Urine Cytology
Its sensitivity is higher for high-grade bladder tumors and lower for low-grade tumors; only 15% of patients with “atypical and/or suspicious” cytologic findings may have underlying urinary tract malignancy. Poorly-adhesive grossly abnormal cells suggestive of poorly differentiated tumors and carcinoma in-situ.
Urine Tumor Markers
Urine tumor marker tests detect antigens and other substances unique to cancer cells, mostly of the bladder, including the bladder tumor antigen (BTA) test, nuclear matrix protein 22 (NMP22), carcinoembryonic antigen (CEA), cytokeratin tissue polypeptide-specific antigen (TPS), fluorescence in situ hybridization (FISH) assay, Lewis X antigen, telomerase activity, and urinary bladder cancer tumor marker (UBCTM) tests.
Urine Culture
Detects bacterial cause of UTI particularly from those with irritative voiding symptoms or a history of urinary tract infection.
Serum Creatinine and Calculation of Glomerular Filtration Rate
If the clinical evaluation and urinalysis suggest a glomerular (nephrological) cause of hematuria, then renal function should be measured. Glomerular filtration rate (GFR) is the most reliable estimate of the renal function.GFR cannot be measured directly, so it is estimated using the urinary clearance of a filtration marker. Clearance is the rate at which a substance is cleared from the plasma by excretion in the urine.Serum creatinine is the most commonly used endogenous filtration marker.
Other Blood Tests
When suspecting a nephrological disease, other tests to consider would include complete blood count, blood urea nitrogen, coagulation studies, and serologic studies such as complement levels, antinuclear antibody (ANA), hepatitis B and C titers, antiglomerular basement membrane antibody, antineutrophilic cytoplasmic antibody (ANCA), antistreptolysin O titer (ASO), and cryoglobulin assay.
References
- ↑ Rew, Karl (2010). Primary care urology. Philadelphia, Pa. London: Saunders. ISBN 978-1437724899.
- ↑ "www.surgeryjournal.co.uk".