Immunocompromised Host Infections

Question 1

What are the two classifications of immunodeficiencies?

Answer 1

> Congenital

> Acquired

Question 2

What is the second line of defence after an innate defence breach?

Answer 2

Neutrophil (NE)

Question 3

What causes a NEchemotaxis defect?

Answer 3

> Inadequate signalling
Receptor abnormality
NE abnormal mov’t

Question 4

What causes a NE killing power defect>

Answer 4

NE –I respiratory burst in phagocytosis.

Question 5

Why isn’t hydrogen peroxide formed in a killing power defect?

Answer 5

NADPH oxidase is deficient

Question 6

Give one example of a disease caused by NE killing power defect?

Answer 6

Chronic Granulomatous Disease

Question 7

When would a person develop Neutropenia?

Answer 7

> Cancer treatment
Bone marrow malignancy
Aplastic anaemia

Question 8

What percentage of neutropenic patients develop an infection?

Answer 8

50%

Question 9

Why must a pseudomonal infection be treated immediately?

Answer 9

Fatal otherwise.

Question 10

Under what conditions is neutropenia more serious?

Answer 10

Level :

Question 11

What is the treatment for neutropenic pt’s with infection?

Answer 11

Broad spectrum anti’bs.
> Aminoglycoside then antipseudomonal penicillin
> 2nd line = Carbapenem then anti-fungal.

Question 12

What can cause acquired T cell deficiencies?

Answer 12

> Drugs

> Viruses

Question 13

What bacteria can cause T cell deficiences?

Answer 13

> Mycobacteria

> Listeria moncytogenes

Question 14

What viruses can cause T cell deficiences?

Answer 14

> Varicella Zoster
Cytomegalovirus
Herpes Simplex

Question 15

What fungi can cause T cell deficiencies?

Answer 15

Cryptococcus and Candidas spp.

Question 16

How does Toxoplasma Gondii present itself?

Answer 16

Brain lesion and neurological signs

Question 17

What is the presentation of strongyloides stercoralis?

Answer 17

> Rash of Larva currens

> Asymptomatic

Question 18

What may strongyloides stercoralis cause?

Answer 18

> Gram negative septicaemia

Question 19

What is hypogammaglobulinaemia?

Answer 19

Reduction in gamma globulins inc. antibodies.

Question 20

How is hypogammaglobulinaemia acquired?

Answer 20

> Multiple myeloma
Chronic lymphocytic leukaemia
Burns
Encapsulated bacteria

Question 21

Why is encapsulated bacteria a problem in pt’s with complement deficiency?

Answer 21

Complement is needed to kill encapsulated bacteria.

Question 22

What disease will 50-60% of complement deficient pt’s get?

Answer 22

Neisseria meningitidis - MAC not formed –> no cell lysis.

Question 23

What complement deficiency causes pt’s to get Neisseria Meningitis?

Answer 23

C5-8.

Question 24

What is the function of the spleen?

Answer 24

Complement and B cells source, remove opsonised bacteria from blood.

Question 25

What are some of the causes of Splenectomy?

Answer 25

> Sickle cell anaemia
Haemophilius Influenza
Neisseria Meningitis
Malaria

Question 26

What are antibodies that inhibit cytokine signals used for?

Answer 26

Conditions like RA

Question 27

What is the negative side fx of antib’s that inhibit cytokine signals?

Answer 27

More susceptible to:
> TB
> Herpes zoster
> Legionella pneumophilia
> Listeria monocytogenes

Question 28

What does anti-rejection treatment suppress?

Answer 28

Cell mediated immunity - cytotoxic T cells and natural killer cells