Determination of total urine protein is used to evaluate patients with kidney disease and as a screening test in the investigation of monoclonal gammopathies.
The semi-quantitative determination of protein in a random urine sample is part of the general urine test. A small amount of protein in the urine is considered normal and consists of albumin and low molecular weight plasma proteins (β2 microglobulin, globulins, haptoglobin, light chains and Tamm-Horsfall glycoprotein). The presence of protein in the urine is a key indicator of renal impairment.
Urine albumin quantification is necessary when a random urine sample tests positive for more than 'trace' albumin. Normally, only low molecular weight proteins are small enough to pass through the glomerular membrane to the glomerular filtrate and most of them are resorbed by the renal tubes. Proteinuria is a major indicator of renal impairment and may result from glomerular leakage, tubular dysfunction, renal tissue damage, or excessive low molecular weight protein concentrations. Transient proteinuria can result from non-pathological conditions such as physical or emotional stress and body position. The various protein substances are excreted at different rates and at different times over a 24-hour period.Thus, timed 24-hour urinalysis for albumin provides a more accurate picture of kidney function.
Possible Interpretations of Pathological Values
- Non-kidney diseases: Abdominal tumor, aging, severe anemia, ascites, bacterial toxins (acute streptococcal, diphtheria, pneumonia, scabies, typhoid fever), heart disease, central nervous system, central nervous system damage, hypersensitivity reaction, hyperthyroidism, infection (acute), ingestion or overexposure to certain substances (arsenic, carbon tetrachloride, ether, lead, mercury, mustard, opiate, phenol, nephylic acid, propylene glycol, propylene glycol) a lymphocyte), subacute bacterial endocarditis, toxemia, trauma.
- Temporary proteinuria: Dehydration, nutrition (excessive protein intake), emotional stress, cold exposure, intense exercise, fever, orthostatic hypotension, meteoromorphic proteinuria, sodium deficiency. Medications: Epinephrine, levarterenol.
- Kidney Diseases: Amyloidosis, Bence Jones proteinuria associated with myeloma, congestive heart failure, convulsions, exercise, leukemia (myelocytic), orthostatic hypotension, proteinuria, Waldenstria macroglobulinemia.
- Kidney Diseases: Collagen Diseases, Cryoglobinemia, Henoch-Schonlein, Hypertension (Malignant, Kidney), thrombotic thrombocytopenic purpura.
- Glomerular disease: Amyloidosis, diabetic glomerulosclerosis and nephropathy, glomerulonephritis, Goodpasture's syndrome, high molecular weight proteinuria, membranous nephropathy, polycystic disease, pyelonephritis, chronic nephrititis (chronic).
- Interstitial diseases. Bacterial pyelonephritis, calcium or uric acid deposition, idiopathic pharmacological reactions to the following medicines: methicillin, phenytoin, phenyndion, sulfonamides.
- Tuberculosis: Acute tubular necrosis, Bartter's syndrome, β-microglobulinemia, Bright's disease, Butler-Albright's syndrome, Fanconi's syndrome, galactosemia, heavy metal poisoning (cadmium, lead, mercury, zinc, mercury zirconia) acidification.
- Post-renal disease: Cystitis (severe), bone tumor metastases, tumors (bladder, renal pelvis). Proteinuria-inducing medications include: amikacin, amphotericin B, aurothioglucose, bacitracin, gentamicin sulfate, gold, nethilmicin sulfate, neomycin sulfate, penicillins, phenylbutyramide, polymyxin, thymicinximine, polymyxin.
Laboratory test results are the most important parameter for the diagnosis and monitoring of all pathological conditions. 70%-80% of diagnostic decisions are based on laboratory tests. Correct interpretation of laboratory results allows a doctor to distinguish "healthy" from "diseased".
Laboratory test results should not be interpreted from the numerical result of a single analysis. Test results should be interpreted in relation to each individual case and family history, clinical findings and the results of other laboratory tests and information. Your personal physician should explain the importance of your test results.
At Diagnostiki Athinon we answer any questions you may have about the test you perform in our laboratory and we contact your doctor to get the best possible medical care.