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HelpTest Code ABTIR Antibody Titer, Blood and Serum
Shipping Instructions
Specimen must arrive within 72 hours of collection.
Specimen Required
Blood cells, plasma, and serum are required.
Supplies: Sarstedt 5 mL Aliquot Tube (T914)
Specimen Type: Plasma/Blood
Collection Container/Tube: 6-mL Pink top(EDTA)
Submission Container/Tube: Plastic vial
Specimen Volume:
3 mL plasma
3 mL red blood cells (RBC)
Collection Instructions:
1. Centrifuge and aliquot plasma into plastic vial.
2. Label specimens as EDTA plasma or EDTA RBC, as appropriate.
3. Send both tubes.
Specimen Type: Serum/Blood
Collection Container/Tube: 10-mL Red top
Submission Container/Tube: Plastic vial
Specimen Volume:
5 mL serum
5 mL RBC
Collection Instructions:
1. Centrifuge and aliquot serum into plastic vial.
2. Label specimens as serum or clotted RBC, as appropriate.
3. Send both tubes.
Useful For
Monitoring antibody levels during pregnancy to help assess the risk of hemolytic disease of the newborn
This test is not useful for monitoring the efficacy of Rh-immune globulin administration.
Reflex Tests
| Test ID | Reporting Name | Available Separately | Always Performed |
|---|---|---|---|
| ABIDR | Antibody Identification, RBC | Yes | No |
Testing Algorithm
If the antibodies detected are too weakly reactive to titer, this test will be canceled, and the antibody identification will be ordered and performed.
Method Name
Hemagglutination
Reporting Name
Antibody Titer, RBCSpecimen Type
VariesSpecimen Minimum Volume
Blood: 6 mL EDTA
Pediatric: 2 mL serum
Specimen Stability Information
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Varies | Ambient (preferred) | 4 days | |
| Refrigerated | 4 days |
Reject Due To
No specimen should be rejected.Clinical Information
Some maternal IgG alloantibodies to red blood cell antigens will cross the placenta and cause hemolysis of antigen-positive fetal red blood cells. The resulting fetal anemia and hyperbilirubinemia can be harmful or possibly fatal to the newborn.
Reference Values
Negative,
If positive, result will be reported as the reciprocal of the highest dilution at with macroscopic agglutination (1+) is observed.
Interpretation
The specificity of the maternal alloantibody will be stated. The titer result is the reciprocal of the highest dilution at which macroscopic agglutination (1+) is observed.
If the antibody problem identified is not relevant in hemolytic disease of the newborn or if titrations are not helpful, the titer will be canceled and will be replaced by ABIDR / Antibody Identification, Blood and Serum.
A consultation service is offered, at no charge, regarding the clinical relevance of red blood cell antibodies.
Cautions
Recent administration of Rh-immune globulin may cause anti-D to be identified and appear falsely as an alloantibody.
Method Description
The strength and specificity of the antibody to be titered is first determined. Two-fold serial dilutions of serum are tested against antigen-positive erythrocytes. The result is the reciprocal of the highest dilution at which macroscopic agglutination (1+) is observed at the antihuman globulin phase of testing. Parallel titration of a previous specimen of the patient's serum (frozen) provides a baseline for comparison of antibody level. In the absence of a previous specimen from the patient, parallel titration of a control antiserum is used for standardization.(Fung MK, Eder AF, Spitalnik SL, Westhoff CM: Technical Manual. 19th ed. AABB; 2017)
Day(s) Performed
Monday through Friday, Sunday
Report Available
1 to 2 daysSpecimen Retention Time
14 daysPerforming Laboratory
Mayo Clinic Laboratories in Rochester
Test Classification
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.CPT Code Information
86886
86870 (if appropriate-per panel tested)
86860 (if appropriate)
86880 x 3 (if appropriate)
86905- (if appropriate)
86978 (if appropriate)
81403 (if appropriate)-Internal only
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| ABTIR | Antibody Titer, RBC | 50962-0 |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| SPECR | Antibody Specificity | 888-8 |
| ALTIR | Allo Antibody Titer | In Process |
| CTPSR | Current Titer of Previous Specimen | In Process |