Immunodeficiency
The immune system is a complex and highly developed system whose function is to seek and kill invaders. If a person is born with a severely defective immune system, death from infection by a virus, bacterium, fungus or parasite will occur. In severe immunodeficiency, the lack of an enzyme means that toxic waste1 builds up inside the immune system cells, killing them and devastatilng the immune system as a consequence.
Most immune disorders result from either an excessive immune response or an autoimmune attack. Asthma and Crohn's Disease (inflammatory bowel disease) both result from an over-reaction of the immune system, while some types of diabetes are due to the immune system a1ttacking healthy cells and molecules. A key part of the immune system·s role is to differentiate between invaders and the body''s own cells - autoimmune disease is the result of its failure to make this distinction.
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Can you give a definition of immunodeficiency and congenital syndrome?
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1 Can you give examples of toxic waste in the environment?
Congenital syndromes
A congenital syndrome1 is a disorder that originates in a developing foetus and appears during the first month of life. In some cases, the disorder might result in a malformation, which is often referred to as a birth defect or congenital anomaly. lt can be inherited or non-inherited, involve a chromosomal abnormality or refer to the structure or function of parts of the body.
An inherited congenital syndrome involves the transmission of defective or abnormal genes from one parent or both parents to their child. Other forms involve chromosomal abnormalities, such as a missing chromosome or the presence of an extra one.
In functional congenital syndromes, some organs or body systems appear normal, but do not work properly. For example, VSD (Ventricular Septal Defect) affects the way the heart muscle works.
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1 A syndrome is the collection of signs and symptoms that are associated with a disease, condition or disorder.
