Immunology Immunodeficiency Disorders
and Hypersensitivity Reactions 10th Edition
2026
Primary immunodeficiency
-less common and occur in result of single gene defects
(defect on the development of the immune system)
-this could involve antibody deficiencies, B- and T- cell
deficiencies, defects in the phagocytic cells and
deficiency of complement
-something is lacking with the immune system
Ex: B-lymphocyte deficiency is one of the most common
forms of primary immunodeficiency
Examples of primary immunodeficiency
-Chronic Granulomatous Disease of Childhood
-DiGeorge Syndrome
-Familial Mediterranean fever
-Job Syndrome
-Common Variable Immunodeficiency
Secondary Immunodeficiency
,-conditions where the immune system becomes
compromised because of a complication of some other
physiological condition or disease
-can be caused by cancer, effect from a drug
(chemotherapeutic agents that suppress immune
system), and infections that compromise the immune
system
Ex: Patient with HIV gets pneumocystis carinii
What is is a predominant cause of secondary immune
deficiencies worldwide?
-malnutrition
Examples of secondary immunodeficiency
-Pneumocystis Carinii
-HIV
-PNA
-Sinus infection
-Lung cancer
Hypersensitivity Type I
- allergic reaction
-mediated by IgE
,-mast cells are the primary effector cells involved
-inflammation due to mast cell degranulation
Hypersensitivity Type I symptoms
Local: itching, rash
Systemic: wheezing
Hypersensitivity Type I example
Most dangerous form: anaphylactic reaction -> systemic
response -> hypertension -> severe bronchoconstriction
Treatment: epinephrine reverses the effects
Hypersensitivity Type II
-cytotoxic reaction
-tissue/organ specific
-macrophages are primary effector cells involved
-can cause tissue damage or alter function
Mechanism: Tissue-specific destruction or impairment
because of:
1. Antibody binding followed by lysis via complement
2. Antibody binding followed by macrophage
phagocytosis
3. Antibody binding followed by neutrophil destruction
, 4. Antibody-dependent cell (NK)-mediated cytotoxicity
5. Antireceptor antibodies
Hypersensitivity Type II examples
1. Grave's disease (hyperthyroidism): altering thyroid
function, but does not destroy thyroid tissue
2. Incompatible blood type (ABO incompatibility):
cell/tissue damage occurs
-severe transfusion reaction -> transfused erythrocytes
destroyed by agglutination or complement-mediated
lysis
3. Drug allergies
4. Hemolytic anemia
Graves disease
-Autoantibodies specific for thyroid tissue impair
receptor for TSH
ABO incompatibility
-Complement damages RBC membrane and cells lyse
Hypersensitivity Type III
and Hypersensitivity Reactions 10th Edition
2026
Primary immunodeficiency
-less common and occur in result of single gene defects
(defect on the development of the immune system)
-this could involve antibody deficiencies, B- and T- cell
deficiencies, defects in the phagocytic cells and
deficiency of complement
-something is lacking with the immune system
Ex: B-lymphocyte deficiency is one of the most common
forms of primary immunodeficiency
Examples of primary immunodeficiency
-Chronic Granulomatous Disease of Childhood
-DiGeorge Syndrome
-Familial Mediterranean fever
-Job Syndrome
-Common Variable Immunodeficiency
Secondary Immunodeficiency
,-conditions where the immune system becomes
compromised because of a complication of some other
physiological condition or disease
-can be caused by cancer, effect from a drug
(chemotherapeutic agents that suppress immune
system), and infections that compromise the immune
system
Ex: Patient with HIV gets pneumocystis carinii
What is is a predominant cause of secondary immune
deficiencies worldwide?
-malnutrition
Examples of secondary immunodeficiency
-Pneumocystis Carinii
-HIV
-PNA
-Sinus infection
-Lung cancer
Hypersensitivity Type I
- allergic reaction
-mediated by IgE
,-mast cells are the primary effector cells involved
-inflammation due to mast cell degranulation
Hypersensitivity Type I symptoms
Local: itching, rash
Systemic: wheezing
Hypersensitivity Type I example
Most dangerous form: anaphylactic reaction -> systemic
response -> hypertension -> severe bronchoconstriction
Treatment: epinephrine reverses the effects
Hypersensitivity Type II
-cytotoxic reaction
-tissue/organ specific
-macrophages are primary effector cells involved
-can cause tissue damage or alter function
Mechanism: Tissue-specific destruction or impairment
because of:
1. Antibody binding followed by lysis via complement
2. Antibody binding followed by macrophage
phagocytosis
3. Antibody binding followed by neutrophil destruction
, 4. Antibody-dependent cell (NK)-mediated cytotoxicity
5. Antireceptor antibodies
Hypersensitivity Type II examples
1. Grave's disease (hyperthyroidism): altering thyroid
function, but does not destroy thyroid tissue
2. Incompatible blood type (ABO incompatibility):
cell/tissue damage occurs
-severe transfusion reaction -> transfused erythrocytes
destroyed by agglutination or complement-mediated
lysis
3. Drug allergies
4. Hemolytic anemia
Graves disease
-Autoantibodies specific for thyroid tissue impair
receptor for TSH
ABO incompatibility
-Complement damages RBC membrane and cells lyse
Hypersensitivity Type III
