L15 Immunodefeciency

Question 1

Where can immunodeficiency occur

Answer 1

B cells
T cells
Complement
Phagocytes

Question 2

What is primary immunodeficiency

Answer 2

Consist of disorders of immune system in which the defect is intrinsic to cells of immune system

Question 3

What is secondary immunodeficiency

Answer 3

Consist of disorders of immune system in which the defect is induced by external factors

Question 4

Defect in phagocyte action

Answer 4

CGD
Caused by mutations in genes encoding for enzyme phagocyte NADPH oxidase which catalyses production of microbicidal reaction oxygen species in lysosomes
Ingested but not killed
Treated by administration of IFN-y and bone marrow transplantation

Question 5

Complement deficiencies

Answer 5

C1,C4,C2 associated with defects in classical pathway—-susceptibility to infections
C3—defect in all pathways which also inc pyogenic infections
c5 to C9 defective cell killing which inc infections by nesseria meningitis and gonorreha

Question 6

T cell deficiency and combined deficiency

Answer 6

Most severe immunodeficiency 
First 6-12 months of life 
Digeorge’s syndrome
Wiskott aldrich syndrome 
Severe combined immunodeficiency

Question 7

Digeorge’s syndrome

Answer 7

Selective t cell deficiency
Defect in t cell maturation
Tetany due to hypocalcemia caused by hypoparathyrdoisim
Cardiac malformations as well

Question 8

Wiskott aldrich syndrome

Answer 8

Combined partial t cell and b cell deficiency
Eczema,thrombocytopenia and immunodeficiency
X linked disease
Mutation in gene that encodes for a protein that binds to cytoskeletal components in hematopoietic cells
Platelets and leukocytes dont develop normally

Question 9

Severe immunodeficiency

Answer 9

Combined functional t and b cell deficiency
Several genetic defects
Die within first year

Question 10

What are the b cell deficiencies

Answer 10

Bruton’s x linked agammaglobulanemia

Common variable immunodeficiency

Question 11

Bruton’s x linked agammaglobulinema

Answer 11

Low levels of ig and virtual absence of cells
Mutation in gene encoding for tyrosine kinase which promotes pre b cell expansion
Treatment with pooled gamma globulins reduces number of infections

Question 12

CVID

Answer 12

failure to produce antibodies against a particular antigen
Defects in various genes involved in b cell maturation and activation or t-b cell interactions
Ability to synthesize igG is reduced
Iv gamma globulin given montly

Question 13

HIV

Answer 13

Infects CD4 cells

Leads to progressive loss of CD4 t cells

Question 14

How can a loss of phagocytosis occur in malignancy

Answer 14

Deficiency in neutrophils

Secretion of TGF-b can suppress a variety of immune responses including th1 cells