Under normal circumstances, protein (albumen) is filtered out by the glomerula (filtering apparatus of the kidney) and is therefore not detectable in the urine, or only in very small amounts. However, if disorders occur, the total protein in the urine is increased – this is referred to as proteinuria.
Hemodynamically, protein is found in the urine after athletic activity or heavy physical work, and further in shock and cardiac insufficiency.
The procedure
Material needed
- 2. morning urine
- 24h collection urine
Preparation of the patient
- Not necessary
Disruptive factors
- Long storage can lead to distorted values
Standard value
| Normal value in mg/die | < 150 |
Indications
- Suspected nephropathies (kidney diseases).
- Suspicion of urinary tract infection or urolithiasis (kidney stones).
Interpretation
Interpretation of increased values
- Acute renal insufficiency (acute renal failure).
- Bence-Jones proteinuria – occurrence of spec. protein cells in the urine in multiple myeloma (plasmacytoma).
- Chronic glomerulonephritis – kidney disease, with inflammation of the renal filterlets (glomeruli).
- Diabetes mellitus (diabetes).
- Gouty kidney
- Hemoglobinuria – appearance of hemoglobin (blood pigment) in the urine.
- Urinary tract infection
- Collagenoses (group of connective tissue diseases caused by autoimmune processes) – systemic lupus erythematosus (SLE), polymyositis (PM) or dermatomyositis (DM), Sjögren’s syndrome (Sj), scleroderma (SSc) and Sharp syndrome (“mixed connective tissue disease”, MCTD).
- Waldenström’s disease (synonym: Waldenström’s macroglobulinemia) – malignant (malignant) lymphoma disease; is counted among the B-cell non-Hodgkin’s lymphomas; typical is an abnormal production of monoclonal immunoglobulin M (IgM) by the lymphoma cells (= monoclonal gammopathy type IgM); Form of paraproteinemia in which there is osteoporosis (bone loss) and episodic purpura (capillary bleeding); in contrast to plasmocytoma, neither osteolysis (bone loss) nor hypercalcemia (calcium excess) are observed.
- Myoglobinuria – appearance of myoglobin (muscle hemoglobin) in the urine.
- Nephrotic syndrome – collective term for symptoms that occur in various diseases of the glomerulus (renal corpuscles); symptoms include: Proteinuria (excretion of protein in the urine) with a protein loss of more than 1 g/m²/body surface per day; hypoproteinemia, peripheral edema due to hypalbuminemia of < 2.5 g/dl in serum, hyperlipoproteinemia (lipid metabolism disorder).
- Plasmocytoma (multiple myeloma).
- Prostatitis – inflammation of the prostate gland.
- Pyelonephritis (kidney-pelvis inflammation).
- Phenacetin kidney – kidney disease due to abuse with phenacetin (painkiller).
- Pregnancy nephropathy (pregnancy-related kidney disease).
- Urolithiasis (kidney stones)
Interpretation of decreased values
- Not relevant to the disease