Definition of Immunocompromised

Cells of the Immune System
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Definition: A state in which a person's immune system is weakened or absent. The opposite of immunocompetent.

Individuals who are immunocompromised are less capable of battling infections because of an immune response that is not properly functioning. Examples of immunocompromised people are those that have HIV or AIDS, are pregnant, or are undergoing chemotherapy or radiation therapy for cancer. Other conditions, such as certain cancers and genetic disorders, can also cause a person to become immunocompromised.

Immunocompromised individuals can sometimes be prone to more serious infections and/or complications than healthy people. They are also more prone to getting opportunistic infections, which are infections that do not normally afflict healthy individuals.

Causes for Immunodeficiency:

  • Genetic - inherited genetic defects, like complement deficiencies
  • Acquired - infections, such as HIV, HTLV, and certain cancers, including leukemia, lymphoma, or multiple myeloma
  • Anatomic - no spleen, no thymus
  • Chronic diseases - such as serious kidney disease (like end-stage renal disease and dialysis), diabetes, cirrhosis (liver disease)
  • Medications - such as steroids (like prednisone), chemotherapy for cancer, radiation, immunosuppressive post-transplant medications, immunosuppressive drugs for a number of different disorders 
  • Physical State - such as pregnancy

It is important to note that not all immunodeficiencies result in the same risk for infection.

Also, young children, especially babies, have not developed their immune systems sufficiently. Babies cannot respond to vaccines at the beginning of life and so rely on their mother's antibodies and protection from the world outside by their caregivers.

Diabetes although often not thought of as an immunocompromised state is actually a common pre-existing condition that leads to many infections seen hospitals throughout the US and the world.

It should also be noted that HIV causes immunosuppression, but most of the risks of infections - that we call opportunistic infections - occur when someone has advanced HIV. The degree of immunosuppression is often tracked by watching the CD4 count, which is the amount of T cells (an important type of immune system cells) that are depleted when HIV advances. Those with CD4 counts under 200 are described as having AIDS - Acquired Immune Deficiency Syndrome. Those with CD4 counts under 50 are at even more risk. When people have AIDS, they are more at risk for infections most people would never get - like a a fungal infection called cryptococcal meningitis, Toxoplasmosis infection affecting the brain, and Pneumocystis pneumonia (PCP) which is a very serious illness caused by the fungus Pneumocystis jirovecii, 

The Medications that Can Make Us Immunosuppressed

People sometimes become immunocompromised after taking medications for certain disorders. In some cases these drugs are used in the fight against cancer or to allow for a bone marrow transplant to be effective to fight cancer. Sometimes, though, the drugs are targeting the immune system head on. In some cases, the immune system creates the disease (as in an autoimmune disease) and so the immune system response needs to be weakened to have the disease come under control.

These disorders include, but are not limited to:

  • Multiple Sclerosis
  • Rheumatoid Arthritis
  • Crohn's Disease
  • Ulcerative Colitis
  • Lupus (or systemic lupus erythematosus (SLE))
  • Psoriasis
  • Sjögren’s syndrome
  • Polyarteritis Nodosa
  • Uveitis in some cases
  • Scleroderma/systemic sclerosis
  • Inflammatory muscle diseases (dermatomyositis and polymyositis)
  • Myasthenia gravis
  • Autoimmune hepatitis
  • Autoimmune hemolytic anemia
  • Juvenile rheumatoid arthritis
  • Idiopathic thrombocytopenic purpura (ITP)

​In addition:

  • ​Patients who have COPD (emphysema or Chronic Obstructive Pulmonary Disease) as well as asthma may be given prednisone which can lower their ability to fight infections. Some patients with asthma and allergies that do not respond to prednisone may also take other immunosuppresive treatments (like a monoclonal antibody).
  • There are also many cancers which are treated with immunosuppressive drugs. Patients with organ (heart, liver, kidney etc) or bone marrow transplants may also be on immunosuppressive drugs.
  • Some unusual diseases also are treated with immunosuppression that are often not heard of outside of hospitals and doctor's offices - like Behcet's Disease, Granulomatosis with polyangiitis (Wegener’s), as well as Pemphigus and Pemphigoid

​The drugs patients take which help suppress their immune systems include, but are not limited to:

  • Azathioprine (Imuran)
  • Cyclosporine (Neoral, Sandimmune, Gengraf)
  • Monoclonal antibodies
  • Steroids (like prednisone (Deltasone, Orasone))
  • Mycophenolate mofetil (Cellcept)
    Methotrexate (Rheumatrex)
  • Leflunomide (Arava)
  • Cyclophosphamide (Cytoxan)
  • Chlorambucil

There are many different types of Monoclonal antibodies which have different targets. These include Rituximab, Infliximab, Adalimumab, Omalizumab, and many others. These drugs generally end in "mab" for monoclonal antibody, but some are known by their trade names. The risks for infection are very different depending on which monoclonal antibody is used.

Losing Your Spleen Can Make You Immunocompromised

Those who have lost their spleens are at increased risk for certain types of bacterial infections, particularly encapsulated bacteria (bacteria that have an outer carbohydrate covering). Anyone who does not have a spleen should have the vaccines for: Neisseria meningitidisHaemophilus influenzae, and Streptococcus pneumoniae. There are many reasons people may have lost a spleen - surgery after trauma or to treat an underlying condition, or directly from an underlying condition (like Sickle Cell Disease).

Pronunciation: im-YOU-noh-KOM-pruh-mized

Also Known As: immunodeficient

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