25.33 : Immunodeficiency Diseases

Immunodeficiency disorders are conditions in which the immune system's ability to fight infectious disease and cancer is compromised or entirely absent. The immune system comprises a complex network of cells, tissues, and organs that work together to protect the body from potentially harmful invaders. When this system is deficient or not functioning properly, it leaves the body susceptible to infections, diseases, or other complications.

There are three main causes of immunodeficiency disorders in humans:

Ill-development of Immunity

This cause refers to situations where the immune system does not develop properly or at all. This could be due to genetic disorders such as Severe Combined Immunodeficiency (SCID), in which a person is born without a functioning immune system. Other examples include DiGeorge syndrome, where a small part of children's DNA is missing, leading to poor immune system development.

Viral Infections

Certain viruses can also cause immunodeficiency disorders. For example, the Human Immunodeficiency Virus (HIV) targets the immune system, specifically the T cells, which are crucial for immune response. Over time, as the number of T cells decreases, the body becomes more susceptible to infections and diseases, a condition known as Acquired Immunodeficiency Syndrome (AIDS).

Immunosuppressive Drugs

Some medications can suppress the immune system, leading to immunodeficiency. These drugs are often used to prevent the body from rejecting a transplanted organ or to control autoimmune diseases such as rheumatoid arthritis or lupus. While these medications can be life-saving, their use can also make the body more susceptible to infections and other diseases.

It's important to note that immunodeficiency disorders can significantly impact a person's quality of life. However, with proper medical care and management, individuals with these conditions can lead fulfilling lives. Early diagnosis and treatment are key to managing these disorders effectively.