Conditions causing secondary antibody deficiency
| Malignancy | Chronic lymphocytic leukaemia |
| Multiple myeloma | |
| Good's syndrome | |
| Non-Hodgkin lymphoma | |
| Immunoglobulin loss | Protein losing enteropathy |
| Nephrotic syndrome | |
| Plasma exchange | |
| Severe dermatitis | |
| Drugs | |
| Anticonvulsants | Phenytoin, carbamazepine, valproate, lamotrigine |
| Immunomodulatory | Long-term or frequent corticosteroids Gold, penicillamine, sulfasalazine cyclophosphamide, azathioprine mycophenolate (in allogeneic and solid organ transplantation) |
| Anti-B-cell antibodies | Rituximab
Belimumab |
| Infections | Epstein-Barr virus, cytomegalovirus, HIV, parvovirus B19, congenital rubella |