Test Id : LDAI
Progentec aiSLE DX Lupus Disease Activity Index, Plasma
Useful For
Suggests clinical disorders or settings where the test may be helpful
Aiding in the assessment of current systemic lupus erythematosus disease activity when used in conjunction with standard clinical assessment
Highlights
This advanced biomarker-based blood test measures current disease activity and helps to support clinicians in the assessment of treatments for patients with systemic lupus erythematosus.
Method Name
A short description of the method used to perform the test
Immunoassay
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
C-X-C Motif Chemokine Ligand 10 (CXCL10/IP-10)
Interferon gamma (IFN-y)
Interleukin-15 (IL-15)
Interleukin-4 (IL-4)
Interferon alpha-2 (IFNa-2)
Interleukin-10 (IL-10)
Interleukin-7 (IL-7)
TNF-Related Apoptosis-Inducing Ligand (TRAIL)
B Lymphocyte Stimulator (BAFF)/BLys
Osteopontin (OPN)
Progentec
Progentec Diagnostics
Specimen Type
Describes the specimen type validated for testing
Plasma
Ordering Guidance
This test is intended to be ordered for adult patients. If the test is ordered for a patient younger than 18 years testing will be canceled.
Shipping Instructions
Specimen must be shipped frozen. Testing will be canceled if received ambient or refrigerated.
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: Yellow top (ACD solution A)
Submission Container/Tube: Plastic vial
Specimen Volume: 1 mL
Collection Instructions:
1. Centrifuge at 1500 x g for 20 minutes.
2. Aliquot plasma into plastic vial.
3. Freeze specimen within 2 hours of collection.
Note: Critical frozen. Separate specimens must be submitted when multiple tests are ordered.
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.
0.5 mL
Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected
| Gross hemolysis | Reject |
| Gross lipemia | Reject |
| Heat-treated specimen | Reject |
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 |
|---|---|---|---|
| Plasma | Frozen | 74 days |
Useful For
Suggests clinical disorders or settings where the test may be helpful
Aiding in the assessment of current systemic lupus erythematosus disease activity when used in conjunction with standard clinical assessment
Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
This test measures the concentrations of a set of immune modulatory soluble mediators, including cytokines, chemokines, and soluble receptors shown to be associated with current disease activity in plasma of patients with systemic lupus erythematosus.(1) A proprietary weighted algorithm is used to calculate the patient’s disease activity index (DAI) score ranging from -100 to +100. The magnitude of the score indicates the patient’s current level of disease activity. Decision curve analysis was used to define cutoff values for low (<-18.3), medium (-18.3 to 24.6), and high (>24.6) activity scores. Applying these cutoff values a maximum sensitivity of 100% and maximum specificity of 93% was observed for the DAI. Additional complementary analyses demonstrated that a patient with a positive score is almost 3 times more likely to have active disease than patient with a negative score (odds ratio =2.9, p<0.0001). A patient with a positive score is over 7 times more likely to have clinically and serologically active (CASA) disease than a patient with a negative score (quiescent disease) with odds ratio of 7.2 (p<0.0001).
The following 10 biomarkers are analyzed and used to calculate the DAI test score: B-lymphocyte stimulator (BLyS/BAFF), CXC motif chemokine ligand 10 (CXCL10/IP-10), interferon alpha-2 (IFN-a2), INF gamma (IFN-y), interleukin-4 (IL-4), IL-7, IL-10, IL-15, osteopontin (OPN), tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). These proteins represent several major immune pathways including chemokine/adhesion (CXCL10/IP-10), homeostasis (IL-7, IL-15), innate (IFN-a2), regulatory (IL-10), Th1-type (IFN-y, OPN), Th-2-type (IL-4), and the TNFR superfamily (BlyS/BAFF, TRAIL).
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.
C-X-C Motif Chemokine Ligand 10 (CXCL10/IP-10): 37-343 pg/mL
Interferon gamma (IFN-y): 0.34-7.80 pg/mL
Interleukin-15 (IL-15): 1.00-4.30 pg/mL
Interleukin-4 (IL-4): 1.000-3.200 pg/mL
Interferon alpha-2 (IFNa-2): 3.600-8.300 pg/mL
Interleukin-10 (IL-10): 1.20-9.50 pg/mL
Interleukin-7 (IL-7): 1.10-12.00 pg/mL
TNF-Related Apoptosis-Inducing Ligand (TRAIL): 26-120 pg/mL
B Lymphocyte Stimulator (BAFF)/BLys: 370-995 pg/mL
Osteopontin (OPN): 14,958-95,972 pg/mL
Interpretation
Provides information to assist in interpretation of the test results
This test measures the concentrations of 10 blood plasma proteins. An algorithm is applied to these concentrations to calculate a disease activity index score that ranges from -100 to +100 with the magnitude indicating the patient’s current systemic lupus erythematosus disease activity.
Cautions
Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
Clinical interpretation of individual biomarker levels has not been established but may be indicative of the pathophysiology of immune, infectious, or inflammatory pathologies.
Clinical Reference
Recommendations for in-depth reading of a clinical nature
1. Munroe M, Blankenship D, DeFreese D, et al. Abstract 0554: A refined disease activity immune index informed by select immune mediators that characterizes clinical disease activity in systemic lupus erythematosus. Arthritis Rheumatol. 2023;75(S9):1089-1092
2. Munroe M, DeJager W, Macwana S, et al. Abstract 1803: Ability of innate, adaptive, and TNF-superfamily immune pathways to characterize disease activity and inform a refined lupus disease activity immune index in a confirmatory cohort of SLE patients. Arthritis Rheumatol. 2020;72(S10)
3. Munroe M, Guthridge J, Lu R, et al. Abstract 1693: Innate, adaptive, and TNF-Superfamily immune pathways inform a lupus disease activity immune index that characterizes disease activity in SLE. Arthritis Rheumatol. 2018;70(S9)
Method Description
Describes how the test is performed and provides a method-specific reference
Analyte specific antibodies are pre-coated onto a microfluidic Simple Plex cartridge. Samples are diluted and added to the cartridge. The sample runs through a microfluidic channel that binds the protein of interest. The Ella platform washes off any unbound analyte and adds a detection reagent. Each channel utilized for analyte capture encompasses three glass nano reactors coated with a capture antibody, providing analyte values in triplicate. A calculated analyte value is then generated from the factory-calibrated standard curve that is built into every cartridge.
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.
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.
Progentec Diagnostics developed and characterized this test. It is intended for clinical use and the reported results should be interpreted in relation to each patient’s clinical condition and medical history. This test is a laboratory developed test (LDT) and is not cleared by the US Food and Drug Administration (FDA). Progentec Diagnostics Clinical Laboratory is certified under the Clinical Laboratory Improvement Amendment (CLIA) of 1988 and accredited by the College of American Pathologists to perform high complexity clinical testing.
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.
0446U
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 |
|---|---|---|
| LDAI | Lupus Disease Activity Index, P | Not Provided |
| 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.
|
|---|---|---|
| DA1 | CXC Motif Ligand 10 (CXCL10)(IP-10) | Not Provided |
| DA2 | Interferon gamma (IFN-g) | Not Provided |
| DA3 | Interleukin 15 (IL-15) | Not Provided |
| DA4 | Interleukin 4 (IL-4) | Not Provided |
| DA5 | Interferon alpha 2 (IFN-a2) | Not Provided |
| DA6 | Interleukin 10 (IL-10) | Not Provided |
| DA7 | Interleukin 7 (IL-7) | Not Provided |
| DA8 | TNF-Relat Apop-Induc Ligand (TRAIL) | Not Provided |
| DA9 | B Lymphocyte Stimulator (BAFF) BLyS | Not Provided |
| DA10 | Osteopontin (OPN) | Not Provided |
| DA11 | aiSLE DX DAI Score | Not Provided |
| DA12 | Comments | Not Provided |