Table 4.
Key characteristics of XLA and CVID
| XLA | CVID | |
| Age of onset | usually by 9–18 months | usually 2nd – 4th decade |
| Family Hx of immunodeficiency | usually +ve | variable* |
| Inheritance | x-linked recessive | variable |
| Diagnosis | ||
| Lymph nodes/tonsils | absent tonsillar tissue | normal tonsillar tissue |
| CD19+ B cell numbers | markedly decreased/absent | normal/low |
| CD4+ T cell numbers | Normal | Variable** |
| CD8+ T cell numbers | Normal | Variable** |
| CD4+ CD8+ ratio | Variable | often decreased |
| Specific Antibody titers | absent | decreased/absent |
| Mutations reported | Btk | TACI, ICOS, BAFF-R, CD19+ |
| Common Complications | Infections | Infections |
| Allergy/Atopy | Allergy/Atopy | |
| CEMA, VAPP | ----- | |
| Autoimmunity | Autoimmunity | |
| Malignancy | Malignancy | |
| Treatment | IGIV | IGIV |
| Symptomatic care | Symptomatic care*** |
*Some familial clustering has been described in the literature, possibly associated with Class II MHC gene complex
**CD4+ and CD8+ numbers may be low or normal
*** Symptomatic care includes antimicrobials, surgical drainage, nebulizer treatment for wheezing, allergy management, avoidance, nutrition, etc.
Abbreviations: TACI, Transmembrane activator and calcium-modulator and cyclophilin ligand interactor, Btk, Bruton's tyrosine kinase, ICOS, inducible costimulatory receptor, CEMA, chronic enteroviral meningoencephalitis, VAPP, vaccine-associated paralytic poliomyelitis, IGIV, intravenous immunoglobulin.