Pathophysiology

Pathophysiology Study Guide

Impaired Infusion Oxygen is vital for the metabolism of cells as it produces energy through ATP. It even prevents the formation of infection in wounds, induces angiogenesis, augments fibroblast proliferation, synthesizes collagen, raises keratinocyte differentiation, and leads to the contraction and healing of wounds. If the vascular pathway is disrupted and the metabolic cells consume more oxygen, the wound is depleted of oxygen and becomes hypoxic. This poor perfusion can be caused due to advancement in age or diabetes. Further, healing is impaired, and the wound is not restored. 2.4 Alterations in Immune Function Primary Immune Deficiencies Primary immune deficiencies occur when the immune system is weak and the body is not able to combat infections and diseases. These disorders are genetic in nature and the individual born with these defects faces difficulty in fighting viral, bacterial, or fungal infections. These disorders range from mild to severe. Some of these immune deficiencies are explained below. Severe Combined Immunodeficiency Severe combined immunodeficiency (SCID) is a rare disorder of the immune system, which is congenital and is characterized by the presence of very little or no immune response. These are defects in the B-lymphocytes and T-lymphocytes of white blood cells, which are responsible for fighting off infections from the body. A person suffering from SCID is prone to episodes of infections such as chicken pox, pneumonia, and meningitis; it can cause death within the first year of life. Severe combined immunodeficiency has various types, with the most common type being due to the mutation of gene XI type. The function of this gene is to encode proteins in the immune cells that promote the development of the interleukin-2 (IL2RG) receptor located in the plasma membrane of immune cells. The IL2RG receptor is responsible for successful communication between the T-cells and B-cells of the immune system. If the receptor is mutated when the body is attacked by infections, healthy communication between the immune cells gets impaired. Therefore, inadequate amounts of T-cells and B-cells are formed, which renders the immune system defenseless. There is another form of SCID that is the consequence of the mutation of the Chromosome 20 and leads to the deficiency of the enzyme adenosine deaminase, also known as ADA deficiency. Wiskott- Aldrich Syndrome Wiskott-Aldrich syndrome is a unique type of primary immunodeficiency, as it not only renders the individual incapable of fighting infections, but also causes abnormal bleeding. This is due to the dysfunctional nature of the platelets, which are responsible for the formation of blood clots. The cause of this primary immunodeficiency is the mutation in the gene that is responsible for encoding the Wiskott-Aldrich syndrome protein. Individuals who suffer fromWiskott-Aldrich syndrome often face

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