Causes of immunodeficiency
| Primary | Antibody deficiency syndromes | Common variable immunodeficiency |
| X linked agammaglobulinaemia | ||
| Selective IgA deficiency | ||
| Cell-mediated deficiency | DiGeorge syndrome | |
| Severe combined immunodeficiency | ||
| Secondary | Malnutrition | |
| Major trauma/surgery | ||
| Lymphoreticular malignancy | Lymphoma | |
| Leukaemia | ||
| Myeloma | ||
| Drugs | Cytotoxic treatment | |
| Immunosuppressant treatment | ||
| Viral | HIV |