Summary:
- Immunodeficiency occurs when the immune system is not working properly.
- As a result, it cannot fight off pathogens that a normal immune system would be able to resist.
- Most commonly, it occurs when T or B cells (or both) do not work as well as they should, or when your body doesn't produce enough antibodies.
- Rarely, the problem is caused by a defective gene.
- Inherited immunodef deficiency disorders that affect B cells include hypogammaglobulinemia, which usually leads to respiratory and gastrointestinal infections.