Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

CP reviewer 1 > Infection in the Immunocompromised > Flashcards

Infection in the Immunocompromised Flashcards

1
Q

What are innate defenses?

A

Innate immunity involves barriers that keep harmful materials from entering your body. These barriers form the first line of defence in the immune response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Examples of innate defenses?

A

Skin (barrier, sebum, normal flora) – e.g. burns

Mucous membranes (tears, urine flow, phagocytes)

Lungs (goblet cells, muco-ciliary escalator. Cystic fibrosis)

Interferons, complement, lysozyme, acute phase proteins

Normal commensal flora in gut – antibiotic treatment alters flora e.g. C. difficile, Candida spp.

(Extremes of age, pregnancy, malnutrition)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the body’s second line of defence?

A

Neutrophils are very important after initial breach of innate defences

i.e. less neutrophils = more infection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What can neutrophil dysfunction be divided into?

A

Quantitative and qualitative disorders

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What characterises a qualitative neutrophil disorder?

A

Defect in cellular function e.g. lose ability to kill or chemotaxis

E.g. inadequate signalling

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What characterises a quantitative neutrophil disorder?

A
  • Inadequate number of mature neutrophils
  • More common

E.g. cancer treatment, bone marrow malignancy, aplastic anaemia - drugs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is an example of a qualitative neutrophil disorder?

A

Chronic Granulomatous Disease (CGD)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is CGD?

A
  • A rare, inherited immunodeficiency that affects certain white blood cells.
  • Phagocytes can’t function properly
  • At risk of bacterial and fungal infections
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the classic bacteria that CGD patients are most at risk of?

A

Staph. aureus infections

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is neutropenia?

A

An abnormally low concentration of neutrophils (a type of white blood cell) in the blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

In general, what is neutropenia classified as?

A

<0.5x10^9/L

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

In neutropenic patients, what infections are most serious?

A

Pseudomonal infections

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Treatment for neutropenic patients?

A

The two primary treatments for neutropenia are antibiotics to fight infection and drugs that help the bone marrow make neutrophils.

Treatment:

  • Broad spectrum antibiotics e.g. Antipseudomonal penicillin +/- gentamicin
  • 2nd line treatment e.g. a carbapenem
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What common bacterial infections do neutropenic patients get?

A
  • E. coli, S. aureus
  • Often normal flora e.g. Coag neg staph

These patients often have lines put in, which can lead to these infections

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What common fungal infections do neutropenic patients get?

A

Candida spp., Aspergillus spp.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is given to neutropenic patients that help the bone marrow make neutrophils?

A

Granulocyte colony-stimulating factor (G-CSF) is a blood growth factor that stimulates the bone marrow to produce more infection-fighting white blood cells called neutrophils.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is T cell deficiency?

A

A deficiency of T cells, caused by decreased function of individual T cells, it causes an immunodeficiency of cell-mediated immunity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What causes congenital T cell deficiencies?

A

T helper dysfunction +/- hypogammaglobulinaemia

rare

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is hypogammaglobulinemia?

A

A problem with the immune system that prevents it from making enough antibodies called immunoglobulins.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What causes acquired T cell deficincies?

A
  • Drugs e.g. ciclosporin after transplantation
  • Steroids
  • Viruses e.g. HIV
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

In patients with T cell deficiencies, which bacteria are they susceptible to?

A

Listeria monocytogenes, Mycobacteria

22
Q

In patients with T cell deficiencies, which viruses– transplants are they susceptible to?

A
  • Herpes viruses: HSV, CMV, VZV.
  • Transplants

Serological testing, prophylaxis and treatment with e.g. aciclovir and ganciclovir

23
Q

In patients with T cell deficiencies, which fungal infections are they susceptible to?

A

Candida spp., Cryptococcus spp.

24
Q

Patients with T cell deficiencies are also susceptible to protozoan and parasitic infections.

One of these is cryptosporidium parvum. What is this?

A

One of several species that cause cryptosporidiosis, a parasitic disease of the mammalian intestinal tract.

  • Oocysts shed by cattle/humans
  • Faecal oral route
25
Q

How can cryptosporidium parvum affect patients with T cell deficiencies?

A

Most patients recover after prolonged illness of up to 3 wks. May take much longer in T-cell deficients.

26
Q

Symptoms of cryptosporidium parvum?

A

Acute, watery, and non bloody diarrhoea.

Can be detrimental in T cell deficients.

27
Q

Hypogammaglobulinaemias can be acquired or congenital.

How can they be acquired?

A

Multiple myeloma, burns

28
Q

What type of bacteria tend to cause problems in patients with hypogammaglobulinaemias?

A

Usually encapsulated bacteria e.g. S. pneumoniae

29
Q

What is treatment for hypogammaglobulinaemias?

A

Immunoglobulin therapy (to replace them)

30
Q

What is complement deficiency?

A

an immunodeficiency of absent or suboptimal functioning of one of the complement system proteins.

31
Q

What are patients with complement deficiency at risk of?

A

Encapsulated bacteria. Need complement to help kill organisms.

Frequent, serious S. pneumoniae infections as poor quality opsonisation

32
Q

What can C5-8 deficiency of the complement system lead to?

A

Neisseria meningitidis

33
Q

What is a splenectomy?

A

surgery to remove the entire spleen

34
Q

What is the role of the spleen?

A

source of complement and antibody producing B-cells, removes opsonised bacteria from blood.

35
Q

What can cause a splenectomy to be needed?

A

traumatic, surgical or functional e.g. sickle cell anaemia

36
Q

What is functional asplenia?

A

Functional asplenia occurs when splenic tissue is present but does not work well (e.g. sickle-cell disease, polysplenia)

37
Q

After a splenectomy, which organisms are patients at risk of?

A

S. pneumoniae, Haemophilus influenzae type B, N. meningitidis, malaria

38
Q

What are biologic drugs?

A

Drugs made from proteins and other substances produced by the body.

Used for some long-term medical conditions, including rheumatoid arthritis, Crohn’s disease, psoriasis

39
Q

How do biologics work?

A

Inhibit inflammatory cytokine signals e.g. tumour necrosis factor or TNF, inhibiting T-cell activation, or depleting B-cells.

40
Q

What can biologics put you at risk of?

A

Risk of tuberculosis, herpes zoster, Legionella pneumophila, and Listeria monocytogenes

41
Q

What are the 2 main types of transplants?

A
  1. Solid organ transplant

2. Stem cells in haematological malignancy (bone marrow transplant)

42
Q

What do anti-rejection treamtments do after transplants?

A

Anti-rejection treatment suppresses cell mediated immunity to stop effects of cytotoxic and natural killer cells.

43
Q

What does the degree of immunosuppression required after transplant depend on?

A

Degree of immunosuppression varies on how closely the donor and recipient are matched and organ involved.

44
Q

Example of diary of infections in transplantation

A
  1. The initial disease e.g. HBV
  2. Surgery and hospital admission e.g. S. aureus wound infection
  3. Organ receipt e.g. Toxoplasmosis, CMV
  4. Opportunistic infection during initial immunosuppression (initial 3/12, e.g. CMV, Aspergillus)
  5. Later opportunistic infection (after 3/12, e.g. Zoster, Listeria)
45
Q

General principles of infections in immunocompromised patients:

A

Treat the known infection – empirical, need specimens from likely site of infection to guide therapy

E.g. remove catheters

Reverse defect if possible/stop immunosuppression

Prevention most important

46
Q

In which patients should live vaccines be avoided?

A

in T-cell deficient

47
Q

Clinical Case 1:

  • 19 yo student, bruising, fever
  • Diagnosed with acute myeloid leukaemia (AML). Chemotherapy started
  • First 2 courses uneventful
  • Few days into final course chemo, febrile neutropenic. Blood cultures E. coli. Given piperacillin/tazobactam.

Where could the focus be?

A

What can cause neutropenia?
- Chemo

E coli may have come from:

  • Ulcers in gut caused by chemo
  • UTI
  • Hospital acquired pneumonia
48
Q

For nosocomial pneumonia and bacterial infections in neutropenic patients, what should be given straight away?

A

Piperacillin with tazobactam

49
Q

Clinical Case 1:

One week later blood cultures have yeast – Candida albicans

Treatment?

A

Candida albicans likely to have come from a line infection

Treatment:

  • Take line out
  • Antifungal therapy (broadspectrum) –> Liposomal amphotericin B, followed by fluconazole treatment
50
Q

What is fluconazole?

A

Fluconazole is an antifungal medicine

CP reviewer 1 (59 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions