Test Catalog

Test Id : LAD1

Leukocyte Adhesion Deficiency Type 1, CD11a/CD18 and CD11b/CD18 Complex Immunophenotyping, Blood

Useful For
Suggests clinical disorders or settings where the test may be helpful

Aiding in the diagnosis of leukocyte adhesion deficiency syndrome type 1, primarily in patients younger than 18 years of age

 

CD11a, CD11b, and CD18 phenotyping

Genetics Test Information
Provides information that may help with selection of the correct genetic test or proper submission of the test request

ITGB2 is located on the long arm of chromosome 21(21q22.3). It encodes the common beta 2 integrin subunit (CD18), which is necessary for the expression of lymphocyte function-associated antigen 1 (CD11a/CD18), Mac-1/CR3 (CD11b/CD18), and p150/95 (CD11c/CD18).

 

Variants in this gene are the underlying cause for the autosomal recessive leukocyte adhesion deficiency type 1.

Method Name
A short description of the method used to perform the test

Flow Cytometric Immunophenotyping

NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.

Yes

Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test

Leukocyte Adhesion Def. Type 1, B

Aliases
Lists additional common names for a test, as an aid in searching

CD11a

CD11b

CD18

LAD (Leukocyte Adhesion Deficiency)

LAD1

Leukocyte Adhesion Deficiency-1

Specimen Type
Describes the specimen type validated for testing

Whole Blood EDTA

Shipping Instructions

Specimens are required to be received in the laboratory weekdays and by 4 p.m. on Friday. Draw and package specimen as close to shipping time as possible.

 

It is recommended that specimens arrive within 24 hours of draw.

 

Samples arriving on the weekend and observed holidays may be canceled.

Necessary Information

Date and time of draw and physician name and phone number are required.

Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing

Container/Tube: Lavender top (EDTA)

Specimen Volume: 5 mL

Collection Instructions: Send whole blood specimen in original tube. Do not aliquot.

Additional Information: For serial monitoring, it is recommended that specimens are collected at the same time of day.

Specimen Minimum Volume
Defines the amount of sample necessary to provide a clinically relevant result as determined by the Testing Laboratory

2 mL

Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected

Gross hemolysis Reject
Gross lipemia 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
Whole Blood EDTA Ambient (preferred) 72 hours PURPLE OR PINK TOP/EDTA

Useful For
Suggests clinical disorders or settings where the test may be helpful

Aiding in the diagnosis of leukocyte adhesion deficiency syndrome type 1, primarily in patients younger than 18 years of age

 

CD11a, CD11b, and CD18 phenotyping

Genetics Test Information
Provides information that may help with selection of the correct genetic test or proper submission of the test request

ITGB2 is located on the long arm of chromosome 21(21q22.3). It encodes the common beta 2 integrin subunit (CD18), which is necessary for the expression of lymphocyte function-associated antigen 1 (CD11a/CD18), Mac-1/CR3 (CD11b/CD18), and p150/95 (CD11c/CD18).

 

Variants in this gene are the underlying cause for the autosomal recessive leukocyte adhesion deficiency type 1.

Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

Leukocyte adhesion deficiency syndrome type 1 (LAD-1) is an autosomal recessive disorder caused by variants in the common chain (CD18) of the beta2-integrin family. LAD-1 is clinically characterized by recurrent infections, impaired wound healing, delayed umbilical cord separation, persistent leukocytosis, and recurrent soft tissue and oral infections.

 

Each of the beta2-integrins is a heterodimer composed of an alpha chain (CD11a, CD11b, or CD11c) noncovalently linked to a common beta2-subunit (CD18). The alpha-beta heterodimers of the beta2-integrin family include lymphocyte function-associated antigen 1 (CD11a/CD18), Mac-1/CR3 (CD11b/CD18), and p150/95 (CD11c/CD18).(1-4) The CD18 gene, ITGB2, and its product are required for normal expression of the alpha-beta heterodimers. Therefore, defects in CD18 expression lead to either very low or no surface membrane expression of CD11a, CD11b, and CD11c.

 

Severe and moderate forms of LAD-1 exist, differing in the degrees of protein deficiency, which are caused by different ITGB2 variants. Two relatively distinct clinical phenotypes of LAD-1 have been described. Patients with the severe phenotype (<1% of normal expression of CD18 on neutrophils) characteristically have delayed umbilical stump separation (>30 days), infection of the umbilical stump (omphalitis), persistent leukocytosis (>15,000/microliter) in the absence of overt active infection, and severe destructive gingivitis with periodontitis and associated tooth loss, and alveolar bone resorption. Patients with the moderate phenotype of LAD-1 (1%-30% of normal expression of CD18 on neutrophils) tend to be diagnosed later in life. Normal umbilical separation, lower risk of life-threatening infections, and longer life expectancy are common in these patients. However, leukocytosis, periodontal disease, and delayed wound healing are still very significant clinical features.

 

Patients with LAD-1 (and other primary immunodeficiency diseases) are unlikely to remain undiagnosed in adulthood. Consequently, this test should not be typically ordered in adults for LAD-1. However, it may be also used to assess immune competence by determining CD18, 11a, and 11b expression.

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.

Normal (reported as normal or absent expression for each marker)

Interpretation
Provides information to assist in interpretation of the test results

The report will include a summary interpretation of the presence or reduction in the level of expression of the individual markers (CD11a, CD11b, and CD18). Expression of the individual markers provides indirect information on the presence or absence of the CD11a/CD18 and CD11b/CD18 complexes.

 

Specimens obtained from patients with leukocyte adhesion deficiency syndrome type 1 (LAD-1) show significant reduction (moderate phenotype) or near absence (severe phenotype) of CD18 and its associated molecules, CD11a and CD11b, on neutrophils and other leukocytes.

 

CD11c expression also is low in LAD-1. The analytical sensitivity of the CD11c assay is insufficient to allow interpretation of CD11c surface expression. Therefore, this test is only for the expression of CD18, CD11a, and CD11b.

Cautions
Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

This test is typically not indicated in adults. For questions about appropriate test selection, call 800-533-1710.

 

Patients with normal beta2-integrin expression without functional activity have been described.(5-6) Therefore, expression of CD18 alone is insufficient to exclude the diagnosis of leukocyte adhesion deficiency syndrome type 1 (LAD-1); functional assays (eg, neutrophil chemotaxis, random migration assays) must be performed if the clinical suspicion is high.

Clinical Reference
Recommendations for in-depth reading of a clinical nature

1. Anderson DC, Springer TA: Leukocyte adhesion deficiency: an inherited defect in the Mac-1, LFA-1, and p150,95 glycoproteins. Ann Rev Med. 1987;38:175-194

2. Corbi AL, Vara A, Ursa A, et al: Molecular basis for a severe case of leukocyte adhesion deficiency. Eur J Immunol. 1992;Jul:22(7):1877-1881

3. Harlan JM: Leukocyte adhesion deficiency syndrome: insights into the molecular basis of leukocyte emigration. Clin Immunol Immunopathol. 1993 June;;67(3 PT2):S16-S24

4. O'Gorman MR, McNally AC, Anderson DC, et al: A rapid whole blood lysis technique for the diagnosis of moderate or severe leukocyte adhesion deficiency (LAD). Ann NY Acad Sci. 1993 Mar 20;;677:427-430

5. Hogg N, Stewart MP, Scarth SL, et al: A novel leukocyte adhesion deficiency caused by expressed but nonfunctional beta2 integrins Mac-1 and LFA-1. J Clin Invest. 1999 Jan;103(1):97-106

6. Kuijpers TW, van Lier RAW, Hamann D, et al: Leukocyte adhesion deficiency type 1 (LAD/1) variant. J Clin Invest. 1997 Oct 1;100(7):1725-1733

7. Hanna S, Etzioni A: Leukocyte adhesion deficiencies. Ann N Y Acad Sci. 2012 Feb;1250:50-55

8. Schmidt S, Moser M, Sperandio M: The molecular basis of leukocyte recruitment and its deficiencies. Mol Immunol. 2013 Aug;55(1):49-58

9. Delmonte OM, Fleisher TA: Flow cytometry: Surface markers and beyond. J Allergy Clin Immunol. 2019 Feb;143(2):528-537

10. Knight V, Heimall JR, Chong H, et al: A toolkit and framework for optimal laboratory evaluation of individuals with suspected primary immunodeficiency. J Allergy Clin Immunol Pract. 2021 Sep;9(9):3293-3307.e6

Method Description
Describes how the test is performed and provides a method-specific reference

Flow cytometric immunophenotyping of peripheral blood is performed to evaluate the presence or absence of the CD11/CD18 complex using monoclonal antibodies directed against the CD11 isoforms, CD11a and CD11b, and CD18 antigens.(O'Gorman MR, McNally AC, Anderson DC, et al: A rapid whole blood lysis technique for the diagnosis of moderate or severe leukocyte adhesion deficiency [LAD]. Ann NY Acad Sci 1993;677:427-430)

PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information

No

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.

Monday through Friday

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.

3 to 4 days

Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded

4 days

Performing Laboratory Location
Indicates the location of the laboratory that performs the test

Rochester

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 Regional Manager. 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 using an analyte specific reagent. Its performance characteristics were determined by Mayo Clinic in a manner consistent with CLIA requirements. This test 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.

86356 x 3

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
LAD1 Leukocyte Adhesion Def. Type 1, B 94266-4
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.
430 CD11a 94268-0
388 CD11b 94267-2
431 CD18 94265-6
432 LAD Interpretation 69052-9
81155 Leukocyte Adhesion Deficiency, B No LOINC Needed

Test Setup Resources

Setup Files
Test setup information contains test file definition details to support order and result interfacing between Mayo Clinic Laboratories and your Laboratory Information System.

Excel | Pdf

Sample Reports
Normal and Abnormal sample reports are provided as references for report appearance.

Normal Reports | Abnormal Reports

SI Sample Reports
International System (SI) of Unit reports are provided for a limited number of tests. These reports are intended for international account use and are only available through MayoLINK accounts that have been defined to receive them.

SI Normal Reports | SI Abnormal Reports