Alpha-2-macroglobulin is an acute-phase protein belonging to the plasma protein group. It is produced primarily in hepatocytes (liver cells), as well as fibroblasts (connective tissue cells) and macrophages (phagocytes). Alpha-2-macroglobulin is involved in many metabolic processes in an inhibitory manner.
Alpha-2-macroglobulin belongs to the marker proteins in urine. These allow the differentiation and monitoring of nephropathies (kidney diseases).
Alpha-2-macroglobulin in urine is a marker for postrenal hemorrhage-induced proteinuria (e.g., due to stones, infections, injuries, tumors).
The procedure
Material needed
- Blood plasma
- 2. morning urine
Preparation of the patient
- Not known
Disruptive factors
- Not known
Standard values
Sample | Normal value |
Blood plasma | 130-300 in mg/dl |
Urine | <10 mg/g creatinine |
Indications
- Diagnosis of microhematuria – blood in the urine but which is not visible.
- Diagnostics in proteinuria – protein in the urine.
- Diagnostics in diabetes mellitus (diabetes)
- Suspicion of acute inflammation, unspecified.
- Suspicion of liver damage
- Suspected nephrotic syndrome – collective term for symptoms occurring in various diseases of the glomerulus (renal corpuscles); the symptoms are proteinuria (excretion of protein in the urine) with a protein loss of more than 1 g/m²/body surface/d; hypoproteinemia, peripheral edema due to hypalbuminemia of < 2.5 g/dl in serum, hyperlipoproteinemia (lipid metabolism disorder).
Interpretation
Interpretation of increased values
- Acute inflammation, unspecified (acute phase protein).
- Diabetes mellitus (diabetes).
- Nephrotic syndrome
Interpretation of decreased values
- Chronic active hepatitis
- Haptoglobin deficiency
- Wilson’s disease.
Further notes
- Marker proteins in urine are:
- Albumin – molecular weight (MG) 66,000; marker for glomerular proteinuria (increased excretion of protein in the urine due to damage to the glomerula (renal corpuscle)).
- Transferrin – MG 90,000; marker for glomerular proteinuria.
- Immunoglobulin G (IgG) – MG 150,000; marker for unselective glomerular proteinuria (indicative of severe glomerular damage).
- Alpha-1 microglobulin – MG 33,000; marker for tubular proteinuria (restriction of tubular reabsorption function).
- Alpha-2-macroglobulin.- MG 750,000; marker for postrenal hemorrhage-induced proteinuria.