Introduction to Infectious Diseases Flashcards Preview

MDCN 350: Course 1 > Introduction to Infectious Diseases > Flashcards

Flashcards in Introduction to Infectious Diseases Deck (36)
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1
Q

direct and indirect transmission of infectious diseases

A

1) direct contact with an affected individual or discharges: airborne, droplet, bloodborne 2) indirect means: vector (animal), famine (inanimate object– virus can live on a doorknob)

2
Q

T/F Infectious diseases make up majority of death in children in the world

A

true. 64% are due to infectious diseases like malaria, measles, meningitis, pertussis, AIDS, pneumonia

3
Q

most common hospital acquired infections

A

UTI, pneumonia, and surgical infections. Theres also a breeding ground for antibiotic resistance

4
Q

superbug

A

highly drug resistant organisms that are created through constant mutation because of our overuse of antibiotics

5
Q

clinical syndrome

A

the sun of signs of any morbid state, a typical constellation of symptoms, physical findings and diagnostic tests which characterize a primary disease process - a “pattern” of signs and symptoms May be as a result of a number of different underlying primary disease processes (infectious and non-infectious)

6
Q

a clinical syndrome may be systemic or ___

A

focal: involve a specific organ like hepatitis systemic: many organ systems like influenza like illness

7
Q

infectious causes of hepatitis

A

viruses (A, B, C) Bacteria (salmonella) Fungi and yeast (Candida) Parasites (malaria)

8
Q

non infectious causes of hepatitis

A

medications and toxins (acetaminophen, alcohol), autoimmune (lupus) inherited conditions (WD, hemochromatosis) cryptogenic (can’t figure out the cause)

9
Q

contiguous vs hematogenous spread

A

contiguous: local infection due to breach in natural barriers hematogenous “seeded” from a systemic infection

10
Q

tropism

A

only certain cells and tissue support the growth of a particular pathogen

11
Q

colonization vs infection

A

infection: when body site is sterile colonization: when body site isn’t sterile ex/ infection in mouth

12
Q

how does a fever come to be?

A
  1. microorganism releases exogenous pyrogens 2. leukocytes rally but produce endogenous pyrogens 3. hypothalamus releases PGE2 to increase set point. 4. PGEs cause vasoconstriction, shivering, behavioural changes, and increased metabolism which results in fever.
13
Q

example of endogenous and exogenous pyrogens

A

endogenous: cytokines: ex/ interleukein I, G or TNF alpha can act on the hypothalamus to produce fever via the release of PGE2. exogenous: bacterial endotoxins. they interact with macrophages to activate the cell mediated immune system.

14
Q

cause of rigors during infection

A

they’re shaking chills. a violent attack of uncontrolled shivering/shaking associated with chills and fever. caused by the effect of PGE2 on peripheral nerves to induce a reflexive shivering phenomena– tense muscles produce heat.

15
Q

4 cardinal signs of local infection

A
  1. warmth 2. erythema 3. edema 4. pain. 5. BONUS: psu. due to dead neutrophils.
16
Q

pathogens that induce pus formation

A

pyogenic. ex/ streptoccocus pyogenes (strep throat) causes tonsils to become ulcerated.

17
Q

possible infection?

A

malaria

18
Q

if a person is IgG positive and IgA negative they are likely:

A

vaccinated or were previosuly infected, but are well now

19
Q
A
20
Q

how does Staph aureus permeate into the soft issue/extracellular invasion?

A

via hyaluronidase (proteases and enzymes allow organism to move deeper into soft tissue)

21
Q

how does listeria infect host?

A

through intracellular invasion: they survive phagocytosis

22
Q

how does strep pneumo end up causing meningitis?

A

via dissermination: they pass the innate immune system and get into lymphatics/blood stream and then onto end organ targest.

23
Q

examples of enterotoxin

A

ehec via shigella toxin

24
Q

how does staph auereus cause toxic shock syndrome?

A

via exotoxin release of superantigens: causes non-specific stimulation of T cells –> uncontrolled cytokine release.

25
Q

example of an endotoxin

A

LPS on a cell wall of a gram negative bacteria. can trigger inflammatory response and sepsis but it is inherent to the bacteria– they do not produce it as a toxin.

26
Q

type 1 hypersensitivity reaction (autoimmune response)

A

anaphylaxis/rash due to IgE response.

27
Q

type II hypersensitivity reponse (immune mediated damage)

A

apoptosis via cytotoxicity. (ex/ cell necrosis due to Hep B)

28
Q

bacteria-caused Type III immune complexes (autoimmune response to infection)

A

fever and inflammation: post-streptococcal glomerulonephritis

29
Q

bacteria-caused type IV hypersensitivity immune response (autoimmune response to infection)

A

delayed type. T cell mediated, causes granulomas or endemic fungii.

30
Q

H. pylori transformation

A

recall: transformation is the ability for some organisms to favor the development of cancer.

Hpylori is linked to gastric adenocarcinoma

31
Q

How does HIB overtly outsmart the immune system?

A

Via T cell infeciton– they destroy CD4_ cells.

32
Q

name examples of infections that use capsules to covertly evade the immune system

A

streptococcus pneumo or pyogenes

haemophilus influenzar

neisseria meningitidis

cryptococcus neoformans

Yes, Some Killer Baceria Have Nice Capsules (yersinia, strep, klebsiella, bacillus, haemophilus, neisseria, cryptococcus neoformans)

33
Q

examples of bacteria that use biofilm production as a method of avoiding the immune system

A

coagulase negative staphylococci.

34
Q

example of virus that uses antigenic variation to evade the immune system

A

influenzae. H1N1;H3N2 etc.

35
Q

example of infection that uses mimicry to evade the immune system

A

shistosoma haemotobium (liver fluke)– coats itself with host antigens to evade the immune repsonse.

36
Q
A