Chem 7 Flashcards
(46 cards)
What is immunity?
The ability of the human body to tolerate ‘self’ material and eliminate ‘nonself’ material.
Define immunodeficiency.
A state in which the immune system’s ability to fight infectious disease and cancer is compromised or entirely absent.
What is primary immunodeficiency?
Immunodeficiency caused by genetic or developmental defects in the immune system, present at birth but may show later in life.
What is secondary or acquired immunodeficiency?
Loss of immune function due to exposure to disease agents, environmental factors, immunosuppression, or aging.
What does it mean to be immunocompromised?
A person with any kind of immunodeficiency, particularly vulnerable to opportunistic infections.
Is secondary immunodeficiency more common than primary immunodeficiency?
True.
How are primary immunodeficiency disorders classified?
Based on the site of lesion in the developmental or differentiation pathway of the immune system.
List the main components of the immune system that can be deficient in primary immunodeficiency disorders.
- Humoral immunity
- Cellular immunity
- Combined humoral and cellular immunity
- Phagocytic cells
- Complement proteins
What are the characteristic pathogens for T-cell deficiencies?
Intracellular bacteria, viruses, protozoa, fungi.
What is Reticular dysgenesis?
A rare inherited autosomal recessive disease resulting in immunodeficiency due to mutations in the AK2 gene.
What is Severe Combined Immunodeficiency (SCID)?
A condition where lymphoid progenitor cells are defective, affecting both T and B cell lineages.
What causes X-linked SCID?
A defect in IL-2 involved in lymphocyte proliferation and/or differentiation.
What are the consequences of T cell disorders?
They affect both cell-mediated and humoral immunity, making patients susceptible to viral, protozoal, and fungal infections.
What is DiGeorge’s Syndrome?
An autosomal dominant condition caused by a deletion of a small segment of chromosome 22, characterized by T-cell immunodeficiency.
What is the treatment for DiGeorge’s Syndrome?
A thymic graft taken from an early fetus.
What is Ataxia-telangiectasia?
A deficiency of T cells associated with lack of coordination and dilation of small blood vessels.
What is Wiskott-Aldrich syndrome?
An X-linked disorder with normal T cell numbers but reduced function, leading to severe eczema and thrombocytopenia.
What is X-linked infantile hypogammaglobulinemia?
The most severe hypogammaglobulinemia with very low B cell numbers and immunoglobulin levels.
What is transient hypogammaglobulinemia?
A condition where infants have a delayed synthesis of IgG, which can be treated with gamma-globulin.
What is IgA deficiency?
The commonest of all immunodeficiencies, resulting from a defect in class switching.
What are the defects in the myeloid lineage of the non-specific immune system?
- Phagocytic defects
- Natural Killer (NK) cell defects
- Complement system defects
What is congenital agranulomatosis?
A decrease in neutrophil count due to a defect in myeloid progenitor cell differentiation.
What characterizes chronic granulomatous disease (CGD)?
Marked lymphadenopathy, hepatosplenomegaly, chronic draining lymph nodes, and poor intracellular killing.
What is Chronic granulomatous disease (CGD) characterized by?
Marked lymphadenopathy, Hepato-splenomegaly, Chronic draining lymph nodes, Poor intracellular killing, Low respiratory burst.
Deficiency in NADPH oxidase or cofactor proteins involved in phagocytic respiratory burst.
