Host microbe interactions

Question 1

Which immune system complements are activated to bacteria?

Answer 1

phagocytes
antibody and B lymphocytes
compliment

Question 2

Which immune system complements are activated to Viruses?

Answer 2

T lymphocytes

antibody and B lymphoctes

Question 3

What is produced by the keratinocytes that has antimicrobial properties?

Answer 3

Defensins

Question 4

What do the sebaceous or sweat glands secrete that has antibmicrobial properties?

Answer 4

Fatty acids

Question 5

What is taenia paedis? Where is it most common?

Answer 5

cracking of the skin btw the toes

in patients who are debilitated, with pressure sores in areas that havent been taken good care of

Question 6

Fixed dialation of the bronchus

Answer 6

Decreases the clearance of mucus –> increases the sputum stagnancy and increases infection risk

Question 7

Which immune system complements are activated to Fungi?

Answer 7

Phagocytes
T lymphocytes
Eosinophils

Question 8

Risk factors that increase the risk in genito-urinary system?

Answer 8

Imparied bladder emptying

Catheterisation

Question 9

What are phagocytes?

Answer 9

Part of innate imune response

Swallows the organisation after opsonisation

Question 10

How do phagocytes swallow and kill organisms?

Answer 10

Via oxygen dependent or independent mechanisms

Question 11

What immune system component is responsible for the major control for control of bacteria and fungi like Step,Staph, coliforms, aspergillus and candidia?

Answer 11

Phagocytes

Question 12

What deficiency is seen in those with haematological malignancy like acute leukaemia, myelodysplasia or cytotoxic chemotherapy?

Answer 12

Phagocyte deficiency

Question 13

What is the major function of the CD4 Helper T cells?

Answer 13

Enhance the phagocytes killing of organisms

Question 14

What is the major function of the Cytolytic T-lymphocytes?

Answer 14

Find cells that have abnormalities on the surface (either due to infection or cancer) and kill them directly

Don’t need help from others

Question 15

Which immune system component is helpful to kill intracellular organisms and infected cells?

Answer 15

T lymphocytes

Question 16

Which conditions are T lymphoctes deficient in?

Answer 16

HIV infection (acquired deficiency in CD4+ lymphocytes)

Lymphoma

Primary immunodeficiency syndromes (e.g. SCID)

Question 17

Which cells mature into plasma cells?

Answer 17

B cells

Question 18

Which cells produce immunoglobulins?

Answer 18

B cells or immunoglobulins

Question 19

Which immunoglobulins are produced first and what are their features?

Answer 19

IgM

Fast, first response, weak affinity for antigen

Question 20

Which immunoglobulins are produced second line and what are their features?

Answer 20

IgG

Later on, strong affinity for antigen, takes a few weeks to reach max level

Question 21

How do immunoglobulins help to kill antigens?

Answer 21

Stick to the suface of antigen and trap them for the phagocytes to come and swallow them

Question 22

Which disease has immunoglobulin deficiency as a feature?

Answer 22

Myeloma

Primary immunodeficiency syndrome

Question 23

Which disease affects CD4+ T lymphocytes?

Answer 23

HIV

progressive immunodeficiency

Question 24

When is opportunistic infection seen in HIV patients?

Answer 24

progressive immunodeficiency that has been there for some time

Question 25

Which pathogens commonly cause invasive infections in those with HIV regardless of CD4 count?

Answer 25

pneumococcal (S. pneumoniae) disease (bacteraemia/meningitis/empyema

Question 26

What are the infections a person with CD4 count <350 is susceptible to?

Answer 26

Mycobacterium tuberculosis, candidiasis

Question 27

What are the infections a person with CD4 count <200 cam get?

Answer 27

Pneumocystis jirovecii, Toxoplasma gondii

Question 28

What are the infections a person with CD4 count <100 can get?

Answer 28

Cryptococcus neoformans, Cytomegalovirus (CMV)

Question 29

Which conditions cause functional hyposlenism?

Answer 29

sickle cell disease, cirrhosis and coeliac disease

Question 30

RTA with spenic bleeding, what do you do?

Answer 30

Give vaccination to present susceptibilty to invasive infection from encapsulated organisms Splenectomy Antibiotic prophylaxis with amoxicillin

Question 31

Which encapsulated organisms increase invasive infection risk in hyposplenism?

Answer 31

Streptococcus pneumoniae (pneumococcus) Haemophilus influenzae type B (HiB) Neisseria meningitidis (meningococcus)

Question 32

What is hyposplenism?

Answer 32

Decreased spleen function

Question 33

A few common causes of hyposplenism include:

Answer 33

Splenectomy (trauma, ITP< klymphona etc.) Fucntional hyposplenism (sickle cell, cirrhosis and sickle cell disease)

Question 34

What are the symptoms shown generally by immunocompromised indiviuals?

Answer 34

Not general symptoms like normal people Fever may be absent Lack of inflammatory response (CRP / neutrophilia) Non-specifically unwell, no localising features

Question 35

How do you treat those with infection if they are immunocompromised?

Answer 35

broad spectrum antibiotics in those who are immunocompromised

Question 36

Is immunosuppression levels in acute leukaemia treated with bone marrow transplant high?

Answer 36

Yes, super high

Question 37

What are the strong association steroids have with regards to their usage?

Answer 37

fungal infections (Candida, Aspergillus)

Question 38

What do anti-TNF alpha therapies have a strong association and risk to?

Answer 38

Intracellular infections by Mycobacterium tubercuclosis Fungal infections

Question 39

What drugs are used to treat serious haematological malignancies?

Answer 39

Purine analogues (fludarabine, cytarabine)

Question 40

Which infections are increased wrt to the risk if people use purine analogues?

Answer 40

``` Viral infections (especially Herpes Simplex Virus and Varicella Zoster Virus) Pneumocystis jirovecii ```

Question 41

Why is co-trimoxazole prophylaxis used in patients with HIV?

Answer 41

To prevent pneumocystitis jerovecci pneumonia

Question 42

Which antigungal agent is used in those with bone bmarrow transplants and why?

Answer 42

Itraconazole to prevent invasive aspergillosis

Question 43

Which drug is given to patients with splenectomy and why?

Answer 43

Penicillin V to prevent pneumococcal disease

Question 44

Which groups are give influenza vaccines?

Answer 44

``` Pregnant women Chronic heart/lung/kidney/liver disease Immunocompromise Diabetes Aged >65 years ```

Question 45

Which groups are given vaccination for streptococcus penumoniae infection?

Answer 45

``` Chronic heart/lung/kidney/liver disease Hyposplenism Immunocompromise (including HIV infection) Diabetes Aged >65 years ```

Question 46

Which groups are given haemophilus influenzae vaccine?

Answer 46

All children | Has now essentially eliminated majority of these infections