Exam 4: Dr. Archer Inherited and Acquired Immune Deficiencies

Question 1

Look at overview slides on the immune system

Answer 1

Look at overview slides on the immune system

Question 2

What are primary immunodeficiency diseases?

Answer 2

Inherited defect for components of the immune system

Question 3

What are the primary immunodeficiency diseases due to?

Answer 3

A defect in a particular protein or glycoprotein

Question 4

What are features that a primary immunodeficiency might be present?

Answer 4

Affecting a particular breed
Occurring in young littermate animals
Chronic recurrent infections
Infections of multiple body sites
Failure of infections to respond to standard antibiotic therapy

Question 5

How are primary immunodeficiency disease classified?

Answer 5

Dominant
Recessive
X-linked

Question 6

What are most inherited immunodeficiency diseases cause by?

Answer 6

Recessive gene defects

Question 7

Describe X-linked immunodeficiency

Answer 7

Recessive X-linked defect

Males

Question 8

Describe dominant primary immunodeficiency

Answer 8

Anyone inheriting the abnormal allele is affected

Tend to be less severe and cause a reduction in function rather than a loss of function

Question 9

Describe canine leukocyte adhesion deficiency

Answer 9

Seen only in Irish Red and White setters
Thought to be autosomal recessive
Neutrophils do not express intern surface molecules and so they cannot stick to endothelial cells
Neutrophils cannot get to areas of inflammation

Question 10

What is canine leukocyte adhesion deficiency?

Answer 10

Persistent infection with extracellular bacteria

Infection cannot be cleared due to the defective neutrophil function

Question 11

How do puppies with canine leukocyte adhesion deficiency present?

Answer 11

With recurrent infections
Tend to have a high white cell count
May have a short lived response to antibiotics

Question 12

Describe SCID in foals

Answer 12

Autosomal recessive
Affected individuals lack functional B and T cells
Incapable of producing an antigen specific immune response
Deletion in the gene encoding of a DNA-dependent protein kinase

Question 13

What do most SCID infected foals present with?

Answer 13

Respiratory infections

Question 14

Describe X-linked SCID

Answer 14

Seen in Bassett Hounds and Corgis
Males
Peripheral T cell lymphopenia 
B cells which do not undergo isotype switching to IgG
Reduced production of NK cells

Question 15

What mutation is there with canine XSCID?

Answer 15

In the gene encoding for IL-2 receptor

Question 16

What can quickly set in with canine XSCID?

Answer 16

Opportunistic infections such as bacterial pyoderma, otitis, cystitis, diarrhea secondary to infection

Question 17

What is the most common presenting sign of IgA deficiency in dogs?

Answer 17

Recurrent upper respiratory infections
Otitis
Dermatitis

Question 18

What is C3?

Answer 18

A component of the complement system and important for opsonization of bacteria

Question 19

What is the homozygous C3 deficiency like?

Answer 19

No detectable C3

Question 20

What is the heterozygous C3 deficiency like?

Answer 20

C3 is 50% of normal and animals are clinically normal

Question 21

What is a clinical sign of C3 deficiency?

Answer 21

Increased susceptibility to bacterial infections

Question 22

What is cyclic hematopoiesis in gray collies?

Answer 22

Autosomal recessive disorder

Question 23

What happens with cyclic hematopoiesis?

Answer 23

Sever cyclic neutropenia
Platelet related bleeding
Recurrent bacterial infections
Coat dilutional color

Question 24

What is there a mutation of in cyclic hematopoiesis?

Answer 24

The beta subunit of AP3`

Question 25

What do secondary immunodeficiency diseases develop due to?

Answer 25

A secondary problem and not from an immune system defect present at birth

Question 26

What are big causes of secondary immunodeficiency diseases in small animals?

Answer 26

Infectious agents
Drugs
Endocrine diseases

Question 27

What is a big cause of secondary immunodeficiency diseases in horses?

Answer 27

Failure of passive transfer

Question 28

Describe HIV

Answer 28

RNA virus
Transferred via bodily fluids from infected individuals
Causes slow progressing diseases

Question 29

How does HIV cause slow progressing diseases?

Answer 29

The virus recognizes and binds tightly to CD4, allowing entrance into the cell
Cells which express CD4 include macrophages, DCs, and CD4 T cells

Question 30

How does the virus binding to CD4 alter the immune system?

Answer 30

At the site of virus entry, macrophages and DCs are the first cells to become infected
The virus replicates these initial cells
The virus subsequently infects CD4 T cells
T cell activation causes production of infectious burins, which bud from the cell

Question 31

What happens overtime wth HIV?

Answer 31

Decline in CD4 T cells and progression to AIDS

Question 32

What happens once CD4 T cell numbers in the body drop too low?

Answer 32

An effective immune response to other infectious agents cannot be mounted

Question 33

Describe FIV

Answer 33

Initial viral replication and decline in CD4 T cells–acute phase of infection
Progress to a latent asymptomatic period followed by decline in CD4 T cell numbers
With decreased CD4 cells cytokine alterations and progressive immune dysfunction develop
Failing immune system allows for opportunistic infections, neoplasia, and wasting to occur

Question 34

What is the management for FIV?

Answer 34

Keep indoors and separated from other cats
Regular examinations with blood work
If sick, prompt identification of the secondary illness with treatment

Question 35

Describe canine parvovirus

Answer 35

DNA virus

Trophism for rapidly dividing cells in the GI tract, bone marrow, and lymphoid tissue

Question 36

What are secondary non-infectious cause of immunosuppression?

Answer 36

Failure of passive transfer
Marrow diseases
Endocrine diseases
Drugs (immunosuppressive agents, chemotherapy)