Module 8: Primary immune deficiencies

Question 1

Cellular immune deficiencies

Answer 1

thymic hypoplasia

Nezelof’s syndrome

Question 2

Thymic Hypoplasia

Answer 2

Thymus and parathyroid glands do not develop normally
Patients are hypocalcemic due to lack of PTH

Decreased # of T cells
Lymphopenia
Ig levels normal or decreased

Patients require CMV negative irradiated blood products

Question 3

Nezelof’s Syndrome

Answer 3

Thymus is small with abnormal morphology
Secondary lymph tissue are also reduced in size
Parathyroid is normal

Decreased # of T cells
IVIg if required

Question 4

Humoral immune deficiencies

Answer 4

X-linked agamma-globulinemia (Brutons)
Selective IgA deficiency
Transient Hypogamma-globulinemia of infancy
X-linked hyper-IgM syndrome

Question 5

X linked agamma-globulinemia (burtons)

Answer 5

Defect in B cell maturation due to missing enzyme

Circulating mature B-cells are rare
IgG, IgA, IgM are decreased or absent
No Ab response to antigen stimulation

Question 6

Selective IgA deficiency

Answer 6

Patients have a near or complete absence of serum and secretory IgA

*Patient may develop anti IgA if exposed to blood products
Patients with risk of Anti-IgA risk serious allergic reaction to blood product containing IgA

***DO NOT transfuse IgA containing blood products to patients that have developed Ab to IgA

Question 7

Transient Hypogamma-globinemia of Infancy

Answer 7

Prolongation of the decline in maternal Ig

Question 8

Combined cellular and humeral immunodeficiencies

Answer 8

Severe combined immune deficiency (SCID)
Wiskott-Aldrich Syndrome
Ataxia Telangiectasia

Question 9

Severe combined immune deficiency (SCID)

Answer 9

Failure of lymphoid stem cells to develop

Infants show markedly decreased mature T cell percentage
Both B and T cells non functional
NK cells are deficient
Ig levels very low

Mutation in gene for several cytokine receptors (mutation is Adenosine deaminase enzyme)

Question 10

Wiskott-Aldrich Syndrome

Answer 10

Inability to respond to polysaccharide antigens

Infants have decreased number and function of T cells
B cells are decreased
Thrombocytopenia

Therapy includes PLT transfusions and gamma globulin administration
Treatment: splenectomy, HSC transplant

Question 11

Ataxia Telangiectasia

Answer 11

Defect in DNA repair
T cell deficiency and disordered Ig synthesis

Decrease in Th cells, Ig levels

Question 12

Phagocytic deficiencies

Answer 12

Leukocyte adhesion defect (LAD)
Chronic Granulomatous disease
Chediak Higashi syndrome

Question 13

Leukocyte adhesion defect

Answer 13

Leukocytes cannot adhere to endothelial cells

Cord stub doesn’t heal properly

Question 14

Chronic Granulomatous disease

Answer 14

From impairment of the phagocytes’ ability to produce oxygen radical and hydrogen