Confirmation of intravascular
Nephelometry
Haptoglobin, Serum
Serum
Collection Container/Tube:
Preferred: Serum gel
Acceptable: Red top
Submission Container/Tube: Plastic vial
Specimen Volume:1 mL
Collection Instructions: Centrifuge and aliquot serum into a plastic vial.
0.5 mL
Gross hemolysis | OK |
Gross lipemia | Reject |
Gross icterus | OK |
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Refrigerated (preferred) | 28 days | |
Frozen | 28 days | ||
Ambient | 14 days |
Confirmation of intravascular
Haptoglobin is an immunoglobulin-like plasma protein that binds hemoglobin. The haptoglobin-hemoglobin complex is removed from plasma by macrophages and the hemoglobin is catabolized. When the hemoglobin-binding capacity of haptoglobin is exceeded, hemoglobin passes through the renal glomeruli, resulting in hemoglobinuria.
Chronic intravascular hemolysis causes persistently low haptoglobin concentration. Regular strenuous exercise may cause sustained low haptoglobin, presumably from low-grade hemolysis. Low serum haptoglobin may also be due to severe liver disease.
Neonatal plasma or serum specimens usually do not contain measurable haptoglobin; adult levels are achieved by 6 months.
Increase in plasma haptoglobin concentration occurs as an acute-phase reaction. Levels may appear to be increased in conditions such as burns and nephrotic syndrome. An acute-phase response may be confirmed and monitored by assay of other acute-phase reactants such as alpha-1-antitrypsin and C-reactive protein.
30-200 mg/dL
Absence of plasma haptoglobin may indicate intravascular hemolysis. However, congenital anhaptoglobinemia is common, particularly in African Americans. For this reason, it may be difficult or impossible to interpret a single measurement of plasma haptoglobin. If the assay value is low, the test should be repeated after 1 to 2 weeks following an acute episode of hemolysis. If all the plasma haptoglobin is removed following an episode of intravascular hemolysis and if hemolysis ceases, the haptoglobin concentration should return to normal in a week.
Low levels of plasma haptoglobin may indicate intravascular hemolysis.
Low haptoglobin is normal for the first 3 to 6 months of life.
Haptoglobin is an acute-phase reactant and increases with inflammation or tissue necrosis.
1. Shih AW, McFarlane A, Verhovsek M. Haptoglobin testing in hemolysis: measurement and interpretation. Am J Hematol. 2014;89(4):443-447. doi:10.1002/ajh.23623
2. di Masi A, De Simone G, Ciaccio C, D'Orso S, Coletta M, Ascenzi P. Haptoglobin: From hemoglobin scavenging to human health. Mol Aspects Med. 2020;73:100851. doi:10.1016/j.mam.2020.100851
3. Rifai N. Tietz Textbook of Laboratory Medicine. 7th ed. Elsevier; 2022:1584
Nephelometry.(Siemens Nephelometer II Operations Instruction Manual. Siemens, Inc., Newark, DE)
Monday through Friday, Sunday
This test has been cleared, approved, or is exempt by the US Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.
83010
Test Id | Test Order Name | Order LOINC Value |
---|---|---|
HAPT | Haptoglobin, S | 46127-7 |
Result Id | Test Result Name |
Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
|
---|---|---|
HAPT | Haptoglobin, S | 46127-7 |