Infection in the Immunocompromised Host

Question 1

Describe a qualitative neutrophilic defect and the likely resulting infection

Answer 1

Chronic granulomatous disease- neutrophils fail to mount a respiratory burst in phagocytosis. Deficient in NADPH oxidase so H2O2 not formed. At risk of Staph Aureus infection

Question 2

What infection is likely to result in a neutropenic patient?

Answer 2

Pseudomonal infections

Question 3

Treatment for neutropenic patients

Answer 3

Broad specturm e.g. antipseudomonal penicillin with or without gentamicin.
2nd line treatment e.g. carbapenem
Granulocyte stimulating factors (GCSF) stimulates immune system.

Question 4

Who might get a T cell deficiency

Answer 4

Rare to be congenital

Acquired- drugs e.g. ciclosporin (immunosuppressant) after transplantation, steroids, HIV

Question 5

How might toxoplasma gondii be spead?

Answer 5

Cat faees or heart transplants-may present with lesion in brain and neurological sing

Question 6

Complement is required to kill what type of bacteria

Answer 6

Encapsulated bacteria:
Strep Pneumo
N. Meningitidis
H, Influenza type B

Question 7

Why might a splenectomy result in immunodeficiency?

Answer 7

The spleen is a source of complement an antibody producing B cells-removes opsonised bacteria from the blood. Causes: trauma, surgical or functional e.g. sickly cell anaemia-many thrombi in spleen that makes it incompetent

Question 8

What infections might be transmitted immediately following transplantation

Answer 8

toxoplasmosis, CMV

Question 9

What type of opportunistic infections during initial immunosuppression following a transplant are likely?

Answer 9

CMV, Aspergillus

Question 10

What type of later opportunistic infections might follow a transplant?

Answer 10

Zoster, Listeria