What is an Immunodeficiency Disorder?

Key points

1. Immunodeficiency disorders disrupt your body’s ability to defend itself against bacteria, viruses, and parasites.
2. There are two types of immunodeficiency disorders: those you are born with (primary), and those that are acquired (secondary).
3. Anything that weakens your immune system can lead to a secondary immunodeficiency disorder.

Immunodeficiency disorders prevent your body from fighting infections and diseases. This type of disorder makes it easier for you to catch viruses and bacterial infections.

Immunodeficiency disorders are either congenital or acquired. A congenital, or primary, disorder is one you were born with. Acquired, or secondary, disorders you get later in life. Acquired disorders are more common than congenital disorders.

Your immune system includes the following organs:

• spleen
• tonsils
• bone marrow
• lymph nodes

These organs make and release lymphocytes. These are white blood cells classified as B cells and T cells. B and T cells fight invaders called antigens. B cells release antibodies specific to the disease your body detects. T cells destroy foreign or abnormal cells.

Examples of antigens that your B and T cells might need to fight off include:

• bacteria
• viruses
• cancer cells
• parasites

An immunodeficiency disorder disrupts your body’s ability to defend itself against these antigens.