Immunodeficiency Disorders:

Immunodeficiency refers to the partial or total loss of one or more components of the immune system, which can significantly increase susceptibility to infections and cancer due to compromised immunosurveillance. There are two main types of immunodeficiency: primary and secondary (acquired).

Primary Immunodeficiency Disorders:

Primary immunodeficiencies result from developmental failures or genetic abnormalities in the immune system. Conditions like Severe Combined Immunodeficiency (SCID) a group of medical disorders, are depicted by a range of various defects affecting the production or function of lymphocytes (B cells, T cells, and/or NK cells).  Primary immunodeficiencies can negatively impact innate immunity (such as phagocyte function and complement pathway) and/or adaptive immunity (e.g., antibody or leukocyte deficiencies).

Secondary (Acquired) Immunodeficiency Disorders:

On the other hand, secondary immunodeficiencies are more common and arise from external factors that impair immune function. Causes include infections like human immunodeficiency virus (HIV), which targets and reduces helper T cells, leading to acquired immunodeficiency syndrome (AIDS).  Surgical removal of lymphoid tissues (such as splenectomy), malnutrition, liver disease affecting plasma proteins, and prolonged use of immunosuppressants (common after organ transplants) also contribute. Additionally, therapies like radiation and chemotherapy for cancer can suppress bone marrow function and lower white blood cell counts, weakening the immune response.

Immunocompromised individuals are particularly vulnerable to opportunistic infections, where normally harmless flora or pathogens can cause severe illness. They also face challenges in developing immunity through vaccines or prior infections. Preventive measures for those with immunodeficiency include prophylactic antimicrobial drugs and gamma globulin treatments to prevent infections and boost immunity.

Furthermore, the reduced ability to surveil and eliminate cancerous cells increases the risk of cancer development in immunodeficient individuals.  Special considerations in healthcare settings, such as dental procedures, include prophylactic antibiotics to prevent infections in vulnerable patients.  Dental professionals should be informed of any immunosuppressive conditions to take appropriate precautions and ensure patient safety during treatment.

Summary of Above Text in Point Form:

• Immunodeficiency: Partial or total loss of one or more immune system components.
  • Risks: Increased risk of infections and cancer due to impaired immunosurveillance.
• Causes of Immunodeficiency:
  • Primary Immunodeficiency:
    • Developmental failure in the immune system.
    • Over 300 different genetic defects of the immune system exist (e.g., SCID, severe combined immunodeficiency = a range of genetic defects negatively affecting lympocytes (B cells, T cells, and/or NK cells) causing abnormalities in innate immunity (affecting function of phagocytes, complement pathway) and/or adaptive immunity (e.g., antibody deficiencies,
  • Secondary (Acquired) Immunodeficiency:
    • More common than primary immunodeficiency
    • Causes:
      • HIV infection targeting helper T cells leading to T cell deficiency and AIDS.
      • Removal of lymph tissue (e.g., splenectomy).
      • Malnutrition.
      • Liver disease reducing plasma proteins.
      • Splenectomy, or damage to spleen (e.g. from trauma or sickle-cell anemia)
      • Long-term use of immunosuppressants (e.g., post-organ transplant).
      • Radiation and chemotherapy causing low white blood cell counts.
      • Cancer depleting nourishment, causing nausea, blood loss, and suppressing bone marrow.
      • Long-term use of anti-inflammatories or immunosuppressants like glucocorticoids. DMARDs
      • Endogenous production of glucocorticoids due to mental or physical stress.
      • Aging
• Vulnerable to Opportunistic Infections:
  • Cause: Normal flora causing infections due to weakened immune system.
  • Reduced ability to build up immunity through vaccines or prior infections
  • Preventive Measures:
    • Prophylactic antimicrobial drugs to prevent infections.
    • Gamma globulin treatments (antibody therapy).
• Vulnerable to Cancer due to decreased cancer immunosurveillence
• Special Considerations:
  • Prophylactic antibiotics before dental procedures for immunocompromised individuals.
  • Informing dental professionals of immunosuppressive conditions for appropriate precautions.
  • Primary Immunodeficiency:  In Canada, 1 in 300 people are affected by Seletive IGA deficiency, 1 in 50,000-70,000 people are affected by SCID and over 29,000 Canadians are affected by some form of Primary Immunodeficiency.
  • Global Statistics:  In 2020, it was estimated that 37.7 million people are living with HIV.
  • Canadian Statistics:  Approximately 2,000 Canadians are diagnosed with HIV every year.  In 2018, reports indicate there were over 62,000 Canadians living with HIV.