- Red, tiger top, or gel barrier tube
- 3-5 mL of venous blood
Additional information
- Avoid exercise prior to collection
- Handle sample gently to prevent hemolysis
- Haptoglobin testing is a quantitative analysis of haptoglobin in the blood
- Haptoglobin is a
2- globulin type of glycoprotein synthesized primarily in the liver. It has three major phenotypes, namely 1-1, 2-1, and 2-2 - Haptoglobin irreversibly binds free hemoglobin that is released from lysed RBCs into the circulation. The haptoglobin-hemoglobin complex is rapidly removed by the reticuloendothelial system and metabolized to amino acids and iron, thus preventing iron loss and kidney damage during hemolysis
- Haptoglobin is also an acute phase reactant
- The clinical utility of the haptoglobin assay includes:
- As an index for hemolysis
- Aids in early recognition of hemolysis in HELLP syndrome in pregnant women
- Assists in the investigation of suspected transfusion reactions
- Aids in the differentiation of hemoglobinuria from myoglobinuria
- Aids in the evaluation of chronic liver disease
- Evaluation of disorders involving a diffuse inflammatory process or tissue destruction
- Haptoglobin phenotypes and subtypes are used as a supplement to blood group and HLA testing to establish paternity
- In acute intravascular hemolysis, haptoglobin concentration decreases rapidly and may remain low for 5–7 days, until the liver synthesizes more Haptoglobin
- The concentration of haptoglobin is inversely related to the degree of hemolysis and to the duration of hemolytic episode
- Normal Haptoglobin levels measured during inflammatory episodes or during steroid treatment do not rule out hemolysis (as it is an acute phase reactant also)
- Haptoglobin levels cannot be used to determine whether the basic hemolytic process is intravascular or extravascular
- Hemolysis may clinically present as:
- Back pain
- Chills
- Fever
- Flushing
- Distended neck veins
- Hypotension
- Tachycardia
- Tachypnea
Additional information
- Haptoglobin is absent in 90% of neonates and levels gradually increase to normal adult levels by age 4-12 months
- The decrease in haptoglobin (after hemolysis) precedes any drop in hemopexin levels or the appearance of methemalbumin in serum or urine
- There is significant inter-individual variability in haptoglobin levels
- In congenital ahaptoglobinemia, haptoglobin is permanently absent (affects ~1% of population and 4% of Blacks)
- Related laboratory tests include:
- Bilirubin
- Blood group and type
- Direct and indirect Coombs' test
- Free plasma hemoglobin
- Ham's test
- Serum methemalbumin
- Urinary hemosiderin
Consult your laboratory for their normal ranges as these may vary somewhat from the ones listed below.
| Conve. Units (mg/dL) | SI Units (g/L) | |
|---|---|---|
| Newborn – 6 mos | 5-50 | 0.05-0.5 |
| 6 mos - Adult | 25-200 | 0.25-2 |
Conditions associated with elevated haptoglobin levels include:
- Acute rheumatic disease
- Biliary obstruction
- Collagen diseases
- Diabetes mellitus
- Infection
- Inflammation (acute or chronic)
- Major depression
- Neoplasias such as advanced lymphomas
- Pregnancy
- Tissue destruction
- Acute myocardial infarction
- Burns
- Cancers
- Trauma
- Drugs
- Androgens
- Corticosteroids
- Danazol
- Ethylestrenol
- Fluoxymesterone
- Methandrostenolone
- Norethandrolone
- Oxandrolone
- Oxymetholone
- Stanozolol
Conditions associated with decreased haptoglobin levels include:
- Acquired disorders
- Intravascular hemolysis
- Drug induced hemolysis (e.g. methyldopa)
- Hereditary such as hemoglobinopathies
- Immune related such as transfusion reactions, autoimmune hemolytic anemia, erythroblastosis fetalis
- Infectious (e.g. malaria)
- Mechanical such as artificial heart valves, endocarditis, contact sports
- Paroxysmal nocturnal hemoglobinuria (PNH)
- Thrombotic thrombocytopenic purpura
- Acute or chronic liver disease
- Malnutrition
- Ineffective erythropoiesis
- Viral infections such as Cytomegalovirus, Epstein Barr virus
- Newborns
- Regular strenuous exercise
- Inherited disorders
- Glucose 6 Phosphate deficiency
- Hereditary spherocytosis
- Hypohaptoglobinemia or anhaptoglobinemia
- Pyruvate kinase deficiency
- Sickle cell disease
- Thalassemia and megaloblastic anemias
- Drugs
- Acetanilide
- Aminosalicylic acid
- Chlorpromazine
- Dapsone
- Dextran
- Diphenhydramine
- Estrogen
- Furazolidone
- Indomethacin
- Isoniazid
- Nitrofurantoin
- Norethindrone
- Oral contraceptives
- Quinidine
- Resorcinol
- Stibophen
- Streptomycin
- Tamoxifen
- Thiazolsulfone
- Tripelennamine
- Ascenzi P et al. Hemoglobin and heme scavenging. IUBMB Life. 2005 Nov;57(11):749-59.
- Delanghe JR et al. Haptoglobin polymorphism and body iron stores. Clin Chem Lab Med. 2002 Mar;40(3):212-6.
- Laboratory Corporation of America. Haptoglobin. [Homepage on the internet]© 2001. Last updated on August 16, 2006. Last accessed on October 23, 2007. Available at URL: http://www.labcorp.com/datasets/labcorp/html/chapter/mono/sc010500.htm
- LabTestsOnline®. Haptoglobin. [Homepage on the Internet]© 2001-2006. Last reviewed on August 29, 2005. Last accessed on October 23, 2007. Available at URL: http://www.labtestsonline.org/understanding/analytes/haptoglobin/test.html
- Levy AP et al. The effect of vitamin therapy on the progression of coronary artery atherosclerosis varies by haptoglobin type in postmenopausal women. Diabetes Care. 2004 Apr;27(4):925-30.
- Sadrzadeh SM et al. Haptoglobin phenotypes in health and disorders. Am J Clin Pathol. 2004 Jun;121 Suppl:S97-104.
- Treitinger A et al. Lipid and acute-phase protein alterations in HIV-1 infected patients in the early stages of infection: correlation with CD4+ lymphocytes. Braz J Infect Dis. 2001 Aug;5(4):192-9.
- UTMB Laboratory Survival Guide®. HAPTOGLOBIN, serum. [Homepage on the Internet]© 2006. Last reviewed in February,2006. Last accessed on October 23, 2007. Available at URL: http://www.utmb.edu/lsg/LabSurvivalGuide/chem/HAPTOGLOBIN_serum.html