The function of the immune system is to protect against infections and helps in the process of healing andrepair. Sometimes, the immune system fails to protect the body against diseases and malignancies a condition called immunodeficiency. There are two categories of immunodeficiency diseases based onorigin: primary and secondary immunodeficiency diseases.
Primary immunodeficiency (PI) disorders also called congenital immunodeficiencies are genetic and arepresentat birth. The affected miss parts of the immune systems or have faulty defense mechanisms due to genetic defects. They aremuchrarethan the secondary immunodeficiency disorders. Most of themmanifestatinfancyand childhood (Greenberg, 2008). Individuals with PI disorders arehighlysusceptible to infections. The infection depends on the immunodeficiency itself. For instance, B cell deficiency characterized byfeworabsentIgM, IgG lead to susceptibility to Pneumococcal, Streptococcal and Haemophilus infections of the lungs, skin and CNS in early childhood stages (Greenberg, 2008). The few B cells do not produce enough antibodies tofightthese pathogens.
Secondary immunodeficiency disorders are not genetic. One acquires these disorders later in life. Somesecondaryoccurrences or factors cause a decrease in the immune system’s response to diseases. Some of these causes include malnutrition, viral infection, irradiation, cytotoxic drugs, corticosteroids, aging and organ childhood (Greenberg, 2008). These disorders are common. The mostnotableexample is AIDS (Acquired Immuno-Deficiency Syndrome) caused by infection with Human Immunodeficiency Virus (HIV). The virus destroys cells of the immune system leading to high susceptibility to diseases.
Autoimmunity is the breakdown oftolerancemechanisms and induction of immune response against the body’s ownnormalconstituents. The immune system may fail to recognize the body’snormalcomponent as “self” and attacks the cells, tissues or organs causing aninflammationorcompletedamage. When this happens, an autoimmune disease occurs. One example of autoimmune disorders is rheumatic fever where the immune system attacks the “self” cells that have components resembling that of the pathogens. Another autoimmune disease is asthma. It results when allergens cause an inflammatory response that cause clogging of the respiratory pathways (Gillespie & Stephen, 2006).