Test Catalog

Test Id : IGGS

IgG Subclasses, Serum

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

Second-order testing for evaluation of patients with clinical signs and symptoms of humoral immunodeficiency or combined immunodeficiency (cellular and humoral)

Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

Testing includes total IgG as well as the 4 subclasses of IgG.

 

For more information see Celiac Disease Diagnostic Testing Algorithm

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

Turbidimetry

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

IgG Subclasses, S

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

IgG (Immunoglobulin G) Subclasses

IgG1, IgG2, IgG3, IgG4 (Immunoglobulins G1, G2, G3, G4)

Immunoglobulin G (IgG)

Subclasses, IgG (Immunoglobulin G)

Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

Testing includes total IgG as well as the 4 subclasses of IgG.

 

For more information see Celiac Disease Diagnostic Testing Algorithm

Specimen Type
Describes the specimen type validated for testing

Serum

Ordering Guidance

If testing for immunoglobulin subclass IgG4-related disease, the most appropriate test to order is IGGS4 / IgG4, Immunoglobulin Subclasses, Serum.

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

Patient Preparation: Fasting preferred but not required

Collection Container/Tube:

Preferred: Serum gel

Acceptable: Red top

Submission Container/Tube: Plastic vial

Specimen Volume: 1 mL

Collection Instructions: Centrifuge and aliquot serum into a plastic vial.

Special Instructions
Library of PDFs including pertinent information and forms related to the test

Forms

If not ordering electronically, complete, print, and send General Request (T239)

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

See Specimen Required

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

Gross hemolysis Reject
Gross lipemia Reject
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 Refrigerated (preferred) 14 days
Ambient 14 days
Frozen 14 days

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

Second-order testing for evaluation of patients with clinical signs and symptoms of humoral immunodeficiency or combined immunodeficiency (cellular and humoral)

Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

Testing includes total IgG as well as the 4 subclasses of IgG.

 

For more information see Celiac Disease Diagnostic Testing Algorithm

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

The most abundant immunoglobulin isotype in human serum is IgG. IgG immunoglobulins are comprised of 4 subclasses designated IgG1 through IgG4. Of total IgG, approximately 65% is IgG1, 25% is IgG2, 6% is IgG3, and 4% is IgG4. Each IgG subclass contains structurally unique portions of the constant region of the gamma heavy chain.

 

The half-life of IgG1, IgG2, and IgG4 is around 22 days, while IgG3 has a half-life of approximately 7 days. The complement classical pathway is activated most strongly by IgG1 and IgG3 followed by weak strength in activation by IgG2. IgG4 does not activate complement. Clustering of multiple IgG molecules is required to activate complement. Both IgG1 and IgG3 bind Fc receptors on phagocytic cells, activate killer monocytes, and cross the placenta via receptor-mediated active transport. IgG1 is the principal IgG to cross the placenta, and neonatal concentrations are similar to maternal concentrations. Neonates have low production of IgG as the result of immaturity of their immune systems, and IgG concentrations fall through infancy, as the maternally-acquired antibody repertoire is cleared.

 

Measurement of the concentrations of IgG subclass proteins in serum is useful in evaluating patients with clinical signs and symptoms of humoral immunodeficiency or combined immunodeficiency (cellular and humoral). Diminished concentrations of one or more IgG subclass protein may occur in the context of hypogammaglobulinemia, eg, common variable immunodeficiency or deficiencies may be selective, usually involving IgG subclass 2. Deficiency of IgG subclass 1 usually occurs in patients with severe immunoglobulin deficiency involving other IgG subclasses. Deficiency of IgG subclass 2 is more heterogeneous and can occur as an isolated deficiency or in combination with deficiency of IgA or IgA and other IgG subclasses. Most patients with IgG2 deficiency present with recurrent infections, usually sinusitis, otitis, or pulmonary infections. Children with deficiency of IgG subclass 2 often have deficient antibody responses to polysaccharide antigens, including bacterial antigens associated with Haemophilus influenzae type B and Streptococcus pneumoniae. Isolated deficiencies of IgG subclass 3 or 4 occur rarely, and the clinical significance of these findings is not clear.

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.

TOTAL IgG

0-<5 months: 100-334 mg/dL

5-<9 months: 164-588 mg/dL

9-<15 months: 246-904 mg/dL

15-<24 months: 313-1,170 mg/dL

2-<4 years: 295-1,156 mg/dL

4-<7 years: 386-1,470 mg/dL

7-<10 years: 462-1,682 mg/dL

10-<13 years: 503-1,719 mg/dL

13-<16 years: 509-1,580 mg/dL

16-<18 years: 487-1,327 mg/dL

> or =18 years: 767-1,590 mg/dL

 

IgG1

0-<5 months: 56-215 mg/dL

5-<9 months: 102-369 mg/dL

9-<15 months: 160-562 mg/dL

15-<24 months: 209-724 mg/dL

2-<4 years: 158-721 mg/dL

4-<7 years: 209-902 mg/dL

7-<10 years: 253-1,019 mg/dL

10-<13 years: 280-1,030 mg/dL

13-<16 years: 289-934 mg/dL

16-<18 years: 283-772 mg/dL

> or =18 years: 341-894 mg/dL

 

IgG2

0-<5 months: < or =82 mg/dL

5-<9 months: < or =89 mg/dL

9-<15 months: 24-98 mg/dL

15-<24 months: 35-105 mg/dL

2-<4 years: 39-176 mg/dL

4-<7 years: 44-316 mg/dL

7-<10 years: 54-435 mg/dL

10-<13 years: 66-502 mg/dL

13-<16 years: 82-516 mg/dL

16-<18 years: 98-486 mg/dL

> or =18 years: 171-632 mg/dL

 

IgG3

0-<5 months: 7.6-82.3 mg/dL

5-<9 months: 11.9-74.0 mg/dL

9-<15 months: 17.3-63.7 mg/dL

15-<24 months: 21.9-55.0 mg/dL

2-<4 years: 17.0-84.7 mg/dL

4-<7 years: 10.8-94.9 mg/dL

7-<10 years: 8.5-102.6 mg/dL

10-<13 years: 11.5-105.3 mg/dL

13-<16 years: 20.0-103.2 mg/dL

16-<18 years: 31.3-97.6 mg/dL

> or =18 years: 18.4-106.0 mg/dL

 

IgG4

0-<5 months: < or =19.8 mg/dL

5-<9 months: < or =20.8 mg/dL

9-<15 months: < or =22.0 mg/dL

15-<24 months: < or =23.0 mg/dL

2-<4 years: < or =49.1 mg/dL

4-<7 years: < or =81.9 mg/dL

7-<10 years: 1.0-108.7 mg/dL

10-<13 years: 1.0-121.9 mg/dL

13-<16 years: < or =121.7 mg/dL

16-<18 years: < or=111.0 mg/dL

> or =18 years: 2.4-121.0 mg/dL

Interpretation
Provides information to assist in interpretation of the test results

Diminished concentrations of all IgG subclasses are found in common variable immunodeficiency, combined immunodeficiency, ataxia telangiectasia, and other primary and acquired immunodeficiency diseases.

 

A diminished concentration of IgG2 protein may be clinically significant in the context of recurrent sinopulmonary infection and may occur with or without concomitant IgA deficiency.

 

Elevated concentration of IgG4 is consistent with, but not diagnostic of, IgG4-related disease.

 

Slightly diminished concentrations of 1 or more IgG subclass proteins are not uncommon, and usually have little clinical significance.

 

Conversely, some individuals with deficient specific antibody responses to polysaccharide antigens may have normal serum concentrations of IgG subclasses.

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

Measurement of IgG subclass proteins is not a first-order test in patients suspected of having an immunodeficiency disease. Quantitation of IgG, IgA, and IgM, along with other first-order tests for immunodeficiency, should be performed first.

 

Elevations in serum IgG4 concentrations are not specific to IgG4-related disease; they are also found in disorders such as multicentric Castleman disease, allergic disorders, Churg-Strauss syndrome, sarcoidosis, and other conditions.

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

1. Schauer U, Stemberg F, Rieger CHL, et al. IgG subclass concentration in certified reference material 470 and reference values for children and adults determined with the binding site reagents. Clin Chem. 2003;49(11):1924-1929

2. Dietzen DJ. Amino acids, peptides, and proteins. In: Rifai N, Horvath AR, Wittwer C, eds. Tietz Textbook of Clinical Chemistry and Molecular Diagnostics. 6th ed. Elsevier; 2018:393-394

3. Vidarsson G, Dekkers G, Rispens T. IgG subclasses and allotypes: From structure to effector functions. Front Immunol. 2014;5:520

4. Napodano C, Marino M, Stefanile A, et al. Immunological role of IgG subclasses. Immunol Invest. 2021;50(4):427-444

5. Barton JC, Barton JC, Bertoli LF, Acton RT. Factors associated with IgG levels in adults with IgG subclass deficiency. BMC Immunol. 2021;22(1):53

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

The determination of the soluble antigen concentration by turbidimetric methods involves the reaction with specific antiserum to form insoluble complexes. When light is passed through the suspension formed a portion of the light is transmitted and focused onto a photodiode by an optical lens system. The amount of transmitted light is indirectly proportional to the specific protein concentration in the test sample.

 

Concentrations are automatically calculated by reference to a calibrations curve stored within the instrument.(Package inserts: Optilite IgG Kit. The Binding Site Group, Ltd: ver.11, 08/2015; Optilite IgG1. The Binding Site Group, Ltd: ver.23, 07/2019; Optilite IgG2. The Binding Site Group, Ltd: ver.23, 07/2019; Optilite IgG3. The Binding Site Group, Ltd: ver.8, 12/2014; Optilite IgG4. The Binding Site Group, Ltd: ver.23, 07/2019)

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.

Same day/1 to 3 days

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

14 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 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 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
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.

82784

82787 x 4

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
IGGS IgG Subclasses, S 47289-4
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.
T_IGG Total IgG 2465-3
IGG1 IgG 1 2466-1
IGG2 IgG 2 2467-9
IGG3 IgG 3 2468-7
IGG4 IgG 4 2469-5

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 | PHP Pdf | CMS 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