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Flashcards in Infection of the immunocompromised Deck (22):
1

Common types of pathogens more prevalent during immunosuppression.

• Bacteria
• Viruses
• Fungi
• Parasites/Protozoa

2

what functions can be disrupted if you are immnocompromised.

•Disruption of specific defence of an organ/system.
– Can be humoral- B cell and antibodies
– Can be cellular- T cells.

3

innate defences

skin,
Interferons, complement, lysozyme, acute phase proteins
Mucous membrane e.g lungs

4

2 types of immunodeficiences

congenital or acquired

5

what is the second line of defence if the innate system is breached

neutrophils

6

what are the 2 types of neutrophil defects

qualitative- rare
quantitative-common

7

example of qualitative neutrophil defect

– Congenital,
– Inadequate signalling
– Abnormality in receptors or NE movement

8

example of quantitative neutrophil defect

• eg - cancer treatment, bone marrow malignancy, aplastic anaemia caused by drugs
• Neutrophil level 50% will dvlp an infection.

9

typical problems caused by lines

• Bacterial infections – Gram negative bacilli (e.g E. coli), Gram positive cocci (e.g. S. aureus ) - often normal flora which translocate from the blood to the gut. E.g. Coagulase negative staph
• Fungal infections – Candida spp. , Aspergillus spp.

10

Common T cell deficiencies
1 congenital
2 acquired

• Congenital – rare e.g T helper cell disfucntion.
• Acquired – drugs e.g. ciclosporin after transplantation (decreases graft versus host disease and rejection), steroids
• Acquired – viruses e.g. HIV

11

In T cells deficincnecy what types of opportunistic pathogenic organisms are present.

• BACTERIAL – Listeria monocytogenes (food- cheese) this is why it is not recommended in pregnant women, Mycobacteria – MTB, MAI
• VIRAL – e.g. leukaemia and transplanted pnts - HSV, CMV (pre–emptive treatment), VZV. Serological testing, prophylaxis and treatment with e.g. aciclovir and ganciclovir
• FUNGAL – e.g. Candida spp., Cryptococcus spp common in meningitis

12

In T cell deficiency what ypes of parasitic/protazoan infections occur.

• Cryptosporidium parvum
• Toxoplasma gondii
• Strongyloides stercoralis.

13

Is hypogammaglobulinaemia congenital or acquired

acquired- multiple myeloma, chronic lymphocytic leukaemia, burns

14

what is hypoagammaglobinulinaemia

antobody deficency.

15

what is the treatment for Hypogammaglobulinaemias

antibodies and immunoglobulins.

16

Is complement deficiency congenital or acquired

congenital

17

what infection frequently occurs in complement deficiency

S. pneumoniae infections

18

removal of which organ can cause complement deficiency

spleen
source of complement and antibody producing, secondary lypkh organ

19

What is process of organ transplantation and where can infections occur along this process.

• 1. The initial disease (e.g. HBV, liver transplant)
• 2. Surgery and hospital admission (e.g. ventilator acquired pneumonia, S. aureus wound infection)
• 3. Organ receipt (e.g. Toxoplasmosis, CMV), patient matching
• 4. Opportunistic infection during initial immunosuppression (initial 3/12, e.g. CMV, Aspergillus)
• 5. Later opportunistic infection (after 3/12, e.g. Zoster, Listeria)

20

what is the main tests are used to investigate an infection

• Blood cultures. Occasionally bone marrow cultures.
respiratory samples
urine
histology (what is happening at a cellular level)
CT/imaging

21

What methods are used to prevent infections

• Hand washing /aseptic technique / protective isolation / HEPA air filtration (allografts)
• Vaccines (avoid live vaccines in T-cell deficient)- for the 3 encapsulated bacteria.
• Prophylactic antimicrobials (e.g. penicillin, septrin, aciclovir) and passive immunoglobulin
• Special diet

22

what types of infections affect you when you are immunocompromised

common
rare