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HelpTest Code ATR Isoagglutinin Titer, Anti-A, Serum
Shipping Instructions
Specimen must arrive within 10 days of collection.
Specimen Required
Supplies: Sarstedt 5 mL Aliquot Tube (T914)
Collection Container/Tube: Red top
Submission Container/Tube: Plastic vial
Specimen Volume: 2.5 mL
Pediatric Volume: 2 mL
Collection Instructions: Centrifuge and aliquot serum into plastic vial.
Useful For
Evaluation of individuals with possible hypogammaglobulinemia
Investigation of suspected roundworm infections
Method Name
Hemagglutination
Reporting Name
Isoagglutinin Titer, Anti-ASpecimen Type
Serum RedSpecimen Minimum Volume
1 mL
Specimen Stability Information
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Serum Red | Ambient (preferred) | 4 days | |
| Frozen | 10 days | ||
| Refrigerated | 10 days |
Reject Due To
| Gross hemolysis | OK |
Clinical Information
Isoagglutinins are antibodies produced by an individual that cause agglutination of red blood cells (RBC) in other individuals. People possess isoagglutinins directed toward the A or B antigen absent from their own RBC. For example, type B or O individuals will usually possess anti-A. The anti-A is formed in response to exposure to A-like antigenic structures found in ubiquitous non-red blood cell biologic entities (eg, bacteria).
Isoagglutinins present in the newborn are passively acquired from maternal circulation. Such passively acquired isoagglutinins will gradually disappear, and the infant will begin to produce isoagglutinins at 3 to 6 months of age.
Isoagglutinin production may vary in patients with certain pathologic conditions. Decreased levels of isoagglutinins may be seen in patients with acquired and congenital hypogammaglobulinemia and agammaglobulinemia. Some individuals with roundworm infections will have elevated levels of anti-A.
Reference Values
Interpretation depends on clinical setting. No defined reference values.
Interpretation
The result is reported as antiglobulin phase, in general representing IgG antibody. The result is the reciprocal of the highest dilution up to 1:1024 at which macroscopic agglutination (1+) is observed. Dilutions above 1:1024 are reported as greater than 1024.
Cautions
Decreased isoagglutinin titers may be seen in normal elderly individuals and in children 12 months and younger.
This test will not be performed for individuals with blood type A or AB.
Method Description
Two-fold serial dilutions of patient's serum are tested with appropriate type A and B erythrocytes. Antiglobulin phase of reactivity is examined. The result is the reciprocal of the highest dilution at which macroscopic agglutination (1+) is observed up to greater than 1024. Parallel titration of 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 4 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
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| ATR | Isoagglutinin Titer, Anti-A | 38358-8 |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| ATR | Isoagglutinin Titer, Anti-A | In Process |