Lab Test


Test Codes




Specimen Collection Criteria

Collect: One Gold-top SST tube. (Minimum Whole Blood: 4.0 mL)

Contact the Laboratory for the acceptability of other tube types.

Physician Office/Draw Specimen Preparation

Let SST specimen clot 30-60 minutes then immediately centrifuge to separate serum from cells. Refrigerate (2-8°C or 36-46°F) the centrifuged SST tube within two hours of collection.

Preparation for Courier Transport

Transport: Centrifuged SST tube, refrigerated (2-8°C or 36-46°F). (Minimum: 0.5 mL)

Rejection Criteria

  • Plasma specimens.
  • Severely lipemic or hemolyzed specimens.
  • Red-top tubes with serum not separated from cells within two hours of collection.

In-Lab Processing

Let SST specimens clot 30-60 minutes. Centrifuge SST tubes or Microtainers® to separate serum from cells. Deliver immediately to the appropriate testing station.


Specimen Stability for Testing:

Centrifuged SST Tubes and Microtainers® with Separator Gel
Room Temperature (20-26°C or 68-78.8°F): 2-4 hours
Refrigerated (2-8°C or 36-46°F): 7 days
Frozen (-20°C/-4°F or below): Unacceptable

Red-top Tubes and Microtainers® without Separator Gel
Room Temperature (20-25°C or 68-77°F): 2-4 hours
Refrigerated (2-8°C or 36-46°F): Unacceptable
Frozen (-20°C/-4°F or below): Unacceptable

Serum Specimens (Pour-Overs)
Room Temperature (20-26°C or 68-78.8°F): 2-4 hours
Refrigerated (2-8°C or 36-46°F): 7 days
Frozen (-20°C/-4°F or below): 7 days

Specimen Storage in Department Prior to Disposal:

Refrigerated (2-8°C or 36-46°F): 7 days


Dearborn Chemistry Laboratory
Royal Oak Automated Chemistry Laboratory


Royal Oak
Sunday – Saturday, 24 hours a day.
STAT results available within 1 hour of receipt in the Laboratory.
Routine results available within 4 hours.

Reference Range

40-250 mg/dL.
Newborns reach adult levels at about 4 months of age.

Test Methodology



Haptoglobin is decreased in hemolysis, significant liver disease, and less commonly in genetic deficiencies (anhaptoglobinemia, hypohaptoglobinemia). Levels are increased in acute inflammation and with estrogen (oral contraceptive, pregnancy, hormone replacement therapy), androgen and glucocorticoid treatment.

Clinical Utility

Haptoglobin binds to hemoglobin released into the circulation by intravascular hemolysis. Haptoglobin is an acute phase reactant. Serial assays are used to detect and monitor hemolytic states. Haptoglobin is decreased in diseases associated with intravascular hemolysis. In severe hemolysis, haptoglobin may be totally depleted, requiring up to 1 week to return to normal. In chronic hemolytic states such as hemoglobinopathies and mechanical heart valves, there may be a steady decline in haptoglobin levels. In these conditions, serial assays provide a better index of ongoing hemolysis than a single haptoglobin value.

Increased serum haptoglobin levels are present in infection, neoplasia, and other inflammatory conditions characterized by tissue injury and repair.

CPT Codes

LOINC: 4542-7


Last Updated


Microtainer® and Vacutainer® are registered trademarks of Becton, Dickinson and Company.
UroVysion® is a registered trademark of Abbott Laboratories. ThinPrep® is a registered trademark of Hologic, Incorporated.