Immunology - B cell & IG Disorders Flashcards
What do B cells do?
Produce antibodies
Essential component of specific immune system
What is immunoglobulin deficiency called?
Hypogammaglobulinemia
What does hypogammaglobulinemia lead to?
Recurrent infections
Particularly LRTIs
What is the most common immoglobulin deficiency?
Selective Immunoglobulin A deficiency
(only IgA affected)
Where is IgA found?
Mucous membrane secretions e.g.
Saliva
Resp tract
GI tract
Tears
Sweat
IgA protects against opportunistic infections in the membranes
How does selective IgA deficiency present?
Mild immunodeficiency
Often asymptomatic and not diagnosed
Tendency to recurrent mucous membrane infections e.g. LRTIs and autoimmune conditions
When you are most likely to identify IgA deficiency?
When testing for coeliac disease
Blood tests for IgA anti-TTG and anti-EMA
Total IgA is also tested to ensure a more accurate result
What causes common variable immunodeficiency?
Genetic mutation in coding components of B cells
Leads to IgG and IgA deficiency, may also have IgM deficiency
What does common variable immunodeficiency lead to?
Recurrent respiratory tract infections
Leads to chronic lung disease over time
Unable to develop immunity to infections or vaccinations
What conditions are patients with common variable immunodeficiency susceptible to?
Rheumatoid arthritis
Non-Hodgkin’s lymphoma
How is common variable immunodeficiency managed?
Regular immunoglobulin infusions
Treating infections and complications as they occur
What is X-linked agammaglobulinemia?
AKA Bruton’s agammaglobulinemia
X-linked recessive condition
Causes abnormal B cell development and deficiency in all classes of immunoglobulins
Causes similar issues to common variable immunodeficiency
