Alpha-1-microglobulin (synonym: α-1-microglobulin) is a low molecular weight protein (albumin) of the human body. It serves as a marker protein of tubular reabsorption function: in the event of tubular damage, alpha1-microglobulin (32 kD) is secreted in increased amounts because reabsorption is limited.
Alpha-1-microglobulin belongs to the marker proteins in urine. These allow differentiation and follow-up of nephropathies (kidney diseases).
The procedure
Material needed
- 2. morning urine
Preparation of the patient
- Not necessary
Disruptive factors
- Not known
Normal value
| Standard value in mg/l | < 1 |
Indications
- Suspected renal tubular dysfunction.
Interpretation
Interpretation of increased values
- Renal tubular dysfunction
Interpretation of decreased values
- Not relevant to the 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 proteinuria caused by bleeding (e.g., stones, infections, injuries, tumors).
