IgG subclass deficiency
From IDWiki
Background
- A collection of primary immunodeficiencies characterized by normal total IgG but decrease in one or more subclasses of IgG
| Subclass | Proportion of Total IgG1 |
|---|---|
| IgG1 | 60% |
| IgG2 | 32% |
| IgG3 | 4% |
| IgG4 | 4% |
Clinical Manifestations
- The majority of people who have IgG subtype deficiency are asymptomatic
- Symptoms could include recurrent URTI (most common), recurrent pneumonias (more with IgG2+4), recurrent GI infection (more IgG1, IgG2+4, and IgG3+4), bronchiectasis (particularly IgG2+4 and IgG3+4), recurrent HSV (more IgG3 and IgG4 and IgG3+4), and recurrent VZV (most notably IgG3)2
- Associated with autoimmunity in general (may be a symptoms rather than cause)
- May be associated with atopic disease, ataxia-telangiectasia, vasculitis, and IBD (particularly IgG4 deficiency)
- Inflammatory arthritis most notable with IgG1+3
- Thyroid disorders
- May be associated with asthma and COPD, particularly IgG1 and IgG2 deficiencies
| Subclass Deficiency2 | Infections | Immune Dysregulation |
|---|---|---|
| IgG1 | ||
| IgG2 | ||
| IgG3 | VZV | |
| IgG4 | ||
| IgG1+3 | inflammatory arthritis | |
| IgG2+4 | pneumonia, bronchiectasis | splenomegaly |
| IgG3+4 |
References
- ^ Gestur Vidarsson, Gillian Dekkers, Theo Rispens. IgG Subclasses and Allotypes: From Structure to Effector Functions. Frontiers in Immunology. 2014;5. doi:10.3389/fimmu.2014.00520.
- a b Damla Dogru, Yagmur Dogru, Faranaz Atschekzei, Abdulwahab Elsayed, Natalia Dubrowinskaja, Diana Ernst, Torsten Witte, Vega Gödecke, Georgios Sogkas. Reappraisal of IgG subclass deficiencies: a retrospective comparative cohort study. Frontiers in Immunology. 2025;16. doi:10.3389/fimmu.2025.1552513.
