IgG Subclasses
Private IgG Subclasses blood test in London for £199, providing specialist assessment of IgG subclass patterns with results in around 5 days.
Turnaround time
5 business days
Biomarkers count
1
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Overview of the IgG Subclasses Test
The IgG Subclasses blood test provides a more detailed assessment of Immunoglobulin G by examining its four subclasses: IgG1, IgG2, IgG3 and IgG4.
The current London Blood Tests product records this as 1 specialist biomarker group: IgG Subclasses.
Total IgG is the most abundant immunoglobulin in blood, but it is composed of several structurally and functionally distinct subclasses.
IgG1 is the largest subclass and contributes substantially to immune responses against many protein antigens.
IgG2 has an important role in immune responses to polysaccharide antigens, including the capsules of certain bacteria.
IgG3 is particularly effective in several antiviral and protein-antigen responses.
IgG4 is present at a lower concentration and has different immune-regulatory properties.
A person can have a normal total IgG concentration while one or more IgG subclasses are reduced.
For this reason, subclass testing can provide useful additional information when recurrent bacterial respiratory infections continue despite apparently normal routine quantitative immunoglobulins.
Interpretation must be cautious.
A low subclass result alone does not necessarily prove clinically significant immunodeficiency.
The finding becomes more important when it is persistent, associated with recurrent infections and accompanied by an inadequate functional antibody response to vaccines.
Age is also important because normal IgG subclass concentrations vary through childhood.
IgG4 can be increased in several settings. Markedly elevated serum IgG4 may form part of the investigation of IgG4-related disease, but serum IgG4 alone cannot diagnose that condition.
Specialist immunology assessment may therefore be appropriate when results are clearly abnormal or the clinical history is significant.
What Does the IgG Subclasses Test Check?
The test examines the distribution of the four IgG subclasses and can reveal subclass-specific abnormalities that may not be apparent from total IgG alone. This test measures 1 specialist biomarker group.
IgG Subclasses
Assesses the IgG subclass pattern, including IgG1, IgG2, IgG3 and IgG4, to support investigation of selective antibody deficiency, recurrent infection and selected immune disorders.
Who May Benefit From the IgG Subclasses Test?
IgG subclass testing may be useful when recurrent infections persist despite normal or near-normal total immunoglobulin concentrations.
People with recurrent sinus infections - Selective subclass deficiency can impair responses to certain respiratory pathogens.
People with repeated bronchitis or pneumonia - Specialist antibody assessment may be appropriate when infections are frequent.
People with frequent ear infections - Recurrent bacterial respiratory-tract infection can prompt subclass testing.
People whose total IgG is normal despite recurrent infections - This is one of the main reasons to investigate individual subclasses.
People with poor responses to specific vaccines - IgG subclass and functional antibody assessment may be complementary.
People with suspected primary antibody deficiency - Subclass testing can provide information beyond total IgG, IgM and IgA.
People with a previous low IgG subclass result - Repeat testing can determine whether the reduction is persistent.
People undergoing specialist assessment for possible IgG4-related disease - Serum IgG4 may contribute to assessment but cannot establish the diagnosis by itself.
Children with recurrent infections under specialist review - Subclass concentrations change with age, so paediatric interpretation requires age-specific ranges.
How to Prepare
Do not stop immunoglobulin replacement or prescribed immunosuppressive treatment without specialist advice.
Where repeat subclass testing is being used for comparison, similar timing relative to treatment or recent infection improves interpretation.
Symptoms and Reasons to Consider the IgG Subclasses Test
IgG subclass abnormalities are usually suspected because of recurrent infections rather than symptoms directly caused by the laboratory abnormality.
Repeated sinus infections - Reduced antibody responses to respiratory bacteria can contribute.
Frequent ear infections - Recurrent bacterial infection may prompt specialist immune investigation.
Repeated bronchitis - Persistent respiratory infections can occur with clinically important antibody deficiency.
Recurrent pneumonia - Significant or repeated lower-respiratory infection warrants appropriate immunological assessment.
Frequent courses of antibiotics for respiratory infections - Persistent infection burden can justify evaluation of antibody production.
Prolonged recovery from bacterial infections - Ineffective antibody responses are one possible contributor.
Normal total IgG despite a strong history of recurrent infections - Subclass testing may reveal more selective abnormalities.
A previous abnormal subclass measurement - Repeat testing can establish whether the result persists.
A low IgG subclass result does not automatically mean that immunoglobulin-replacement treatment is required.
Clinical significance depends on infection history, persistence of the abnormality, total immunoglobulins and functional antibody responses to vaccination.
How to Book Your IgG Subclasses Test
The IgG Subclasses test can be booked privately for specialist assessment of antibody patterns beyond total IgG.
Choose the IgG Subclasses
Select the specialist IgG Subclasses blood test online.
Select your sample collection option
Choose an in-clinic blood draw or professional home or hotel phlebotomy.
Attend your appointment
A trained healthcare professional collects the required venous blood sample.
Laboratory analysis
Your serum undergoes specialist analysis of the IgG subclass pattern, including IgG1, IgG2, IgG3 and IgG4.
Receive your results securely
Your authorised result is delivered securely and can be reviewed with a GP or immunology specialist where appropriate.
When Will I Receive My Results?
The current expected turnaround for IgG Subclasses is approximately 5 days after your sample reaches the laboratory.
Subclass measurement is more specialised than routine total IgG testing.
The sample undergoes dedicated analysis of the IgG subclass pattern followed by laboratory quality-control procedures and authorisation.
Turnaround starts from laboratory receipt rather than necessarily from the exact time of blood collection.
More extensive immune investigations, including functional vaccine-antibody testing, may require additional samples and separate turnaround periods.
Understanding Your Results
The result should be interpreted using the laboratory's age-appropriate reference intervals for the individual subclass measurements.
A low individual subclass can occur even when total IgG is within its normal range.
This finding becomes more clinically important when the reduction is persistent and the person experiences recurrent infections.
Functional antibody testing can also be important because subclass concentration alone does not show whether the immune system responds effectively to vaccines or pathogens.
A raised subclass is generally less specific.
In particular, an elevated IgG4 concentration can occur with allergic, inflammatory and immune conditions and does not independently diagnose IgG4-related disease.
Children require especially careful interpretation because subclass concentrations change significantly with age.
The complete assessment may therefore include total IgG, IgA, IgM, infection history and functional antibody responses.
Why Book With London Blood Tests?
London Blood Tests provides specialist private IgG subclass assessment for people requiring more detail than a routine total IgG measurement provides.
Detailed IgG assessment - Evaluates the pattern across IgG1, IgG2, IgG3 and IgG4.
Can detect selective abnormalities - A subclass can be reduced despite normal total IgG.
Relevant to recurrent respiratory infections - Particularly useful when sinus, ear or chest infections occur repeatedly.
Useful in suspected antibody deficiency - Provides a more detailed humoral immune assessment.
Can complement vaccine-response testing - Subclass quantity and antibody function answer different immune questions.
Specialist laboratory analysis - Samples undergo dedicated IgG subclass measurement.
Private blood testing in London - Professional clinic and mobile collection can be arranged.
Clear pricing - The IgG Subclasses test costs £199.
Private IgG Subclasses Blood Test in London
London Blood Tests provides private IgG Subclasses testing in London for people requiring detailed assessment of IgG subclass distribution.
The test costs £199 and is recorded as 1 specialist biomarker group covering IgG1, IgG2, IgG3 and IgG4.
Results are expected approximately 5 days after laboratory receipt.
The result should be interpreted with infection history, total immunoglobulin concentrations and functional antibody testing where appropriate.