Immunosuppression

Immunosuppression is the impairment of the body's immune system which can alter the ability of the body's defense mechanisms to prevent diseases, particularly certain infections, including opportunistic infections, and cancers. 

Terminology

Patients with immunosuppression are said to be immunosuppressed, immunocompromised, or immunodeficient. An individual with a normal functioning immune system or a previously immunocompromised patient whose immune system has recovered is said to be immunocompetent. 

A medication that causes immunosuppression can be described as immunosuppressive or an immunosuppressant.

Pathology

Etiology

Immunosuppression has a large number of possible causes. It is sometimes intentional, for example preparing the body for bone marrow transplantation or preventing rejection of organ transplants. Other times it is an unfortunate side-effect, e.g. chemotherapy for cancer.

• iatrogenesis 
  • medication
    • immunotherapies
    • chemotherapy
    • antirejection agents
    • to treat disease (e.g. autoimmune diseases)
  • ionizing radiation
  • surgery (e.g. splenectomy)
  • other procedures e.g. plasmapheresis
• immune disorders e.g. AIDS, lymphoma
• systemic disorders e.g. diabetes mellitus
• malignancy
• chronic renal failure
• cirrhosis and alcoholism
• malnutrition
• genetic e.g. SCID
• radiation sickness e.g. nuclear accidents

See also

• opportunistic infections