Test Id : LAGGN
Granulocyte Antibody Screen, Serum
Useful For
Suggests clinical disorders or settings where the test may be helpful
Work-up of individuals with autoimmune neutropenia
Work-up of individuals having febrile nonhemolytic transfusion reactions
Work-up for alloimmune neonatal neutropenia
This test is not useful for the diagnosis of neutropenia due to marrow suppression by drugs or tumors.
Highlights
This test utilizes two complementary methods to perform granulocyte antibody screening: the granulocyte immunofluorescence test (GIFT) and the granulocyte agglutination test (GAT).
The combined interpretation of GIFT and GAT results is considered the gold standard for granulocyte antibody screening.
The use of both methods improves detection, as no single method identifies all clinically relevant granulocyte antibodies. GIFT is generally more sensitive, while some antibodies, particularly those directed against human neutrophil antigen (HNA)-3a, may be better detected by GAT.
Method Name
A short description of the method used to perform the test
Flow Cytometry/Agglutination
NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.
Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test
Aliases
Lists additional common names for a test, as an aid in searching
Anti-Leukocyte Ab
Anti-Leukocyte Antibodies
Anti-Neutrophil
Antigranulocyte Antibodies
Granulocyte Ab
Granulocyte Binding IgG
LAGGN
LAGGT
Leukoagglutinin
Neutrophil Antibodies
Specimen Type
Describes the specimen type validated for testing
Serum Red
Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing
Supplies: Sarstedt Aliquot Tube, 5 mL (T914)
Collection Container/Tube: Red top (serum gel/SST are not acceptable)
Submission Container/Tube: Plastic vial
Specimen Volume: 1.5 mL Serum
Collection Instructions: Centrifuge and aliquot serum into a plastic vial.
Additional Information: Only a specimen collected before a transfusion reaction is acceptable.
Specimen Minimum Volume
Defines the amount of sample necessary to provide a clinically relevant result as determined by the testing laboratory. The minimum volume is sufficient for one attempt at testing.
Serum: 0.3 mL
Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected
| Gross hemolysis | Reject |
| Gross lipemia | OK |
| Gross icterus | OK |
Specimen Stability Information
Provides a description of the temperatures required to transport a specimen to the performing laboratory, alternate acceptable temperatures are also included
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Serum Red | Refrigerated (preferred) | 30 days | |
| Ambient | 7 days | ||
| Frozen | 365 days |
Useful For
Suggests clinical disorders or settings where the test may be helpful
Work-up of individuals with autoimmune neutropenia
Work-up of individuals having febrile nonhemolytic transfusion reactions
Work-up for alloimmune neonatal neutropenia
This test is not useful for the diagnosis of neutropenia due to marrow suppression by drugs or tumors.
Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Granulocyte antibodies are induced by pregnancy, prior transfusion, or transplants. These antibodies can cause neutropenia in various autoimmune disorders. Febrile nonhemolytic transfusion reactions and alloimmune neonatal neutropenia may also be caused by granulocyte associated antibodies, including anti-human leukocyte antigen antibodies.
Reference Values
Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
Not applicable
Interpretation
Provides information to assist in interpretation of the test results
A screening result is considered positive when reactivity is detected by either method. A positive result indicates the presence of granulocyte-reactive antibodies but does not, by itself, establish HNA antibody specificity.
A positive result can be due to anti-granulocyte antibodies and anti-human leukocyte antigen antibodies.
This test cannot distinguish between allo- or autoantibodies, nor can it determine the specificity of the detected antibody. Results should be correlated to clinical history.
Cautions
Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
Testing for patients who receive human monoclonal antibodies like daratumumab may cause false-positive results due to interfering substances. Hemolytic samples have the potential for causing false-positivity and will, therefore, be rejected.
Clinical Reference
Recommendations for in-depth reading of a clinical nature
1. Flesch BK, Reil A. Molecular genetics of the human neutrophil antigens. Transfus Med Hemother. 2018;45(5):300-309. doi:10.1159/000491031
2. Gottschall JL, Triulzi DJ, Curtis B, et al. The frequency and specificity of human neutrophil antigen antibodies in a blood donor population. Transfusion. 2011;51(4):820-827. doi:10.1111/j.1537-2995.2010.02913.x
3. Browne T, Dearman RJ, Poles A. Human neutrophil antigens: Nature, clinical significance and detection. Int J Immunogenet. 2021;48(2):145-156. doi:10.1111/iji.12514
4. Baig NA, Dukek BA, Falbo DK, et al. Daratumumab interference in flow cytometric anti-granulocyte antibody testing can be overcome using non-human blocking antibodies. Vox Sang. 2021;116(1):116-122. doi:10.1111/vox.12989
Method Description
Describes how the test is performed and provides a method-specific reference
Granulocyte antibody screening is performed using two complementary methods in parallel: the granulocyte immunofluorescence test (GIFT) and the granulocyte agglutination test (GAT).
For both methods, patient serum is incubated with freshly isolated granulocytes from a healthy donor.
In the GIFT method, IgG- and IgM-class antibodies in patient serum that bind to donor granulocytes are detected using fluorescently labeled anti-human immunoglobulin reagents. Samples are analyzed by flow cytometry, and IgG and IgM reactivity are evaluated by comparison with appropriate negative controls.
In the GAT method, antibodies that cause donor granulocytes to agglutinate are detected by bright-field microscopy. Agglutination is assessed based on the extent of cell aggregation observed.(Fung YL, Minchinton RM. The fundamentals of neutrophil antigen and antibody investigations. ISBT Science Series. 2011;6:381-386
PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information
Day(s) Performed
Outlines the days the test is performed. This field reflects the day that the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time before the test is performed. Some tests are listed as continuously performed, which means that assays are performed multiple times during the day.
Tuesday, Thursday
Report Available
The interval of time (receipt of sample at Mayo Clinic Laboratories to results available) taking into account standard setup days and weekends. The first day is the time that it typically takes for a result to be available. The last day is the time it might take, accounting for any necessary repeated testing.
Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded
Performing Laboratory Location
Indicates the location of the laboratory that performs the test
Fees
Several factors determine the fee charged to perform a test. Contact your U.S. or International Regional Manager for information about establishing a fee schedule or to learn more about resources to optimize test selection.
- Authorized users can sign in to Test Prices for detailed fee information.
- Clients without access to Test Prices can contact Customer Service 24 hours a day, seven days a week.
- Prospective clients should contact their account representative. For assistance, contact Customer Service.
Test Classification
Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR) product.
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.
CPT Code Information
Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Clinic Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.
CPT codes are provided by the performing laboratory.
CPT codes are provided by the performing laboratory.
86021 x2
LOINC® Information
Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the order and results codes of this test. LOINC values are provided by the performing laboratory.
| Test Id | Test Order Name | Order LOINC Value |
|---|---|---|
| LAGGN | Granulocyte Ab Screen, S | 105285-1 |
| 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.
|
|---|---|---|
| LAGG2 | GIFT/GAT Interpretation | 105288-5 |
| LAGG3 | GIFT Result | 105286-9 |
| LAGG4 | GAT Result | 105287-7 |