Which of the following is not a common symptom of immunodeficiency disorders?

Explanation: The correct answer is c. Frequent and severe infections. One of the hallmark features of immunodeficiency disorders is an increased susceptibility to infections. Individuals with immunodeficiencies may experience frequent and severe infections, including bacterial, viral, and fungal infections.

Incorrect choices:

a. Excessive inflammation at the site of infection is not a common clinical manifestation of immunodeficiency disorders. Immunodeficiencies are characterized by a weakened immune response, which may result in a reduced inflammatory response to infections.

b. Hyperactive immune response to allergens is seen in allergies and autoimmune disorders, not immunodeficiency disorders.

d. Immunodeficiency disorders are characterized by a lack or dysfunction of specific immune components, such as B cells or T cells, leading to a decreased production of antibodies, not increased.

Explanation: The correct answer is b. X-linked agammaglobulinemia. X-linked agammaglobulinemia is a primary immunodeficiency disorder caused by a genetic mutation that leads to the absence of mature B cells, resulting in an inability to produce antibodies (immunoglobulins). As a result, individuals with this disorder are highly susceptible to infections, especially bacterial infections.

Incorrect choices:

a. DiGeorge syndrome is a primary immunodeficiency disorder characterized by abnormalities in the development of certain organs, including the thymus, leading to impaired T cell function.

c. Severe combined immunodeficiency (SCID) is a group of rare genetic disorders that affect both T cells and B cells, resulting in a severe impairment of the immune system.

d. Acquired immunodeficiency syndrome (AIDS) is a secondary immunodeficiency disorder caused by the human immunodeficiency virus (HIV) infection, which specifically targets and destroys CD4+ T cells, weakening the immune system's ability to fight infections.