Immunocompromised Host Infections Flashcards
What are the two classifications of immunodeficiencies?
> Congenital
> Acquired
What is the second line of defence after an innate defence breach?
Neutrophil (NE)
What causes a NEchemotaxis defect?
> Inadequate signalling
Receptor abnormality
NE abnormal mov’t
What causes a NE killing power defect>
NE –I respiratory burst in phagocytosis.
Why isn’t hydrogen peroxide formed in a killing power defect?
NADPH oxidase is deficient
Give one example of a disease caused by NE killing power defect?
Chronic Granulomatous Disease
When would a person develop Neutropenia?
> Cancer treatment
Bone marrow malignancy
Aplastic anaemia
What percentage of neutropenic patients develop an infection?
50%
Why must a pseudomonal infection be treated immediately?
Fatal otherwise.
Under what conditions is neutropenia more serious?
Level :
What is the treatment for neutropenic pt’s with infection?
Broad spectrum anti’bs.
> Aminoglycoside then antipseudomonal penicillin
> 2nd line = Carbapenem then anti-fungal.
What can cause acquired T cell deficiencies?
> Drugs
> Viruses
What bacteria can cause T cell deficiences?
> Mycobacteria
> Listeria moncytogenes
What viruses can cause T cell deficiences?
> Varicella Zoster
Cytomegalovirus
Herpes Simplex
What fungi can cause T cell deficiencies?
Cryptococcus and Candidas spp.
How does Toxoplasma Gondii present itself?
Brain lesion and neurological signs
What is the presentation of strongyloides stercoralis?
> Rash of Larva currens
> Asymptomatic
What may strongyloides stercoralis cause?
> Gram negative septicaemia
What is hypogammaglobulinaemia?
Reduction in gamma globulins inc. antibodies.
How is hypogammaglobulinaemia acquired?
> Multiple myeloma
Chronic lymphocytic leukaemia
Burns
Encapsulated bacteria
Why is encapsulated bacteria a problem in pt’s with complement deficiency?
Complement is needed to kill encapsulated bacteria.
What disease will 50-60% of complement deficient pt’s get?
Neisseria meningitidis - MAC not formed –> no cell lysis.
What complement deficiency causes pt’s to get Neisseria Meningitis?
C5-8.
What is the function of the spleen?
Complement and B cells source, remove opsonised bacteria from blood.
What are some of the causes of Splenectomy?
> Sickle cell anaemia
Haemophilius Influenza
Neisseria Meningitis
Malaria
What are antibodies that inhibit cytokine signals used for?
Conditions like RA
What is the negative side fx of antib’s that inhibit cytokine signals?
More susceptible to: > TB > Herpes zoster > Legionella pneumophilia > Listeria monocytogenes
What does anti-rejection treatment suppress?
Cell mediated immunity - cytotoxic T cells and natural killer cells
