Brainscape's Knowledge GenomeTM

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


See full index

Respiratory Pharmacology > L16 - antimicrobial chemotherapy > Flashcards

L16 - antimicrobial chemotherapy Flashcards

1
Q

Centor criteria definition

A

gives an indication of the likelihood of a sore throat being due to bacterial infection

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

Centor criteria

A

tender anterior neck glands, fever over 38 degrees, absence of cough

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

IF 3/4 cantor criteria are met…

A

positive predictive value is 40-60%

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

Absence of 3/4 cantor criteria…

A

fairly high negative predictive value of 80%

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

Antiviral

A

a small molecule that works by blocking nucleic acid synthesis or binding a target site on a receptor or enzyme
can prevent through many different areas of virus lifecycle

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

Antiviral usually used in…

A

treatment for humans in influenza A and B, and RSV

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

Flu antiviral

A

neuraminidase inhibitors, competitive inhibitors of flus neuraminidase enzyme
binds to enzyme to prevent vision release therefore halted viral replication

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

Flu antiviral effectiveness

A

shortens symptoms by half a day in adults compared to placebo, no reliable evidence for reducing risk being admitted to hospital or developing other conditions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Flu antiviral NICE indication

A

used for people in at-risk groups, need to start treatment within 48 hours of first symptoms, or 36 within children

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

Ribavirin

A

Nucleoside inhibitor, analogue of guanosine, stops viral RNA synthesis, good in vitro activity against RSV and studies show inconsistent results
reserved for immunocompromised children with severe RSV infection

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

Ribavirin results

A

possible shorter duration, less need for ventilator or oxygen BUT TERATOGENIC
early use of inhaled ribavirin has been shown to reduce morbidity and mortality in adult bone marrow cell transplant recipients

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

Antibiotic

A

molecules that work by binding a target site on a bacteria
target points of biochemical reactions crucial to bacteria survival
crucial binding site varies with antibiotic class

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

S. Pneumoniae

A

gram positive cocci, alpha haemolytic, optocochia sensitive with over 90 serotypes. any age, can be severely ill with respiratory failure or sepsis
invasive pneumococcal disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

S. Pneumonia treatment

A

B-lactam antibiotics i.e. amoxicillin, cefuroxime, cefotaxime
macrolides, clarithromycin, fluoroqinolines and ciproflaxacin

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

H. Influenzae

A

Gram negative cocobacilli, originally thought to be influenza cause, encapsulated or un-encapsulated

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

H. Influenza treatment

A

amoxicillin and calvulanic acid (co-amoxiclave)
tetracyclines - deoxycyclone
but not macrolides

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

Staph. Aureus

A

may complicate recent influenza, ventilator-associated pneumonia

18
Q

Staph. Aureus treatment

A

Flucloxacillin, cerfuroxime, vancomycin, linezolid

19
Q

Klebsiella pneumoniae

A

fram-negative bacilli, enterobacteriacane
normal flora of mouth and intestines
effects mainly homeless, alcoholics and hospital-associated

20
Q

klebsiella pneumoniae treatment

A

Co-amoxiclav and cephalosporins

21
Q

Atypical pathogens

A

difficult to detect as they are intracellular, don’t grow on agar easily and need serology, need special antibiotics

22
Q

Atypical pathogen treatment

A

need special antibiotics as not susceptible to B-lactam and penicillin
macrolides, fluorquinolones and tetracyclines

23
Q

Hospital-acquired pneumonia early onset

A

under 5 days in hospital
organisms similar to CAP and anaerobes
Metronidazole or use a B-lactam with inhibitor of B-lacatamase i.e. co-amoxiclav or piperacillin-tazobactam

24
Q

Hospital-acquired pneumonia late onset

A

over 5 days
Staph. Aureus including methicillin-resistant
Pseudomonas aeruginosa
Acinetobcteria baumanii and klebsiella pneumoniae

25
Q

Pulmonary tuberculosis

A

curable, treat with at least 4 drugs for 6 months

26
Q

TB UK treatment

A

Rifampicin and isoniazid for 6 months or 12 if in CNS

27
Q

Directly observed therapy for TB

A

give meds in supervised fashion 3 or more a week

28
Q

Rifampicin

A

Enters bacilli in a conc-dependent manner, achieving steady-state conc. within 15 mins
Drug binds to B-syunit of DNA-dependent RNA polymerase to form a stable drug-enzyme complex, suppressing chain formation in RNA synthesis

29
Q

Pyrazinamide

A

Activated to pyrazinoic acid under acidic conditions that likely prevail at edges of necrotic TB cavities where inflammatory cells produce lactic acid
inhibition of fatty acid synthase type I leading to interference with mycelia acid synthesis
binding to ribosomal protein S1 and inhibition of trans-translation
reduction of intracellular pH disruption of membrane transport by HPOA

30
Q

Isonazid

A

enters bacilli by passive diffusion
Drug is not directly toxic to bacillus but must be activated to its toxic form within the bacillus by KatG
activated drug forms adducts with bacillary NAD+ and NADP+ that inhibit essential steps in mycelia acid synthesis and nucleic acid synthesis

31
Q

KatG

A

multifunctional catalase peroxidase

32
Q

Mycolic acid

A

part of cell wall

33
Q

Change of antibiotic target

A

bacteria changes the molecular configuration of antibiotic binding or masks it

34
Q

Destruction of antibitoi

A

destroyed or inactivated in susceptible host, inactivation through hydrolysis

35
Q

Prevent antibiotic access

A

modify the bacterial membrane porin channel size, numbers and selectivity

36
Q

Remove antibiotic from bacteria

A

Proteins in bacterial membranes act as an export or efflux protein - so level of antibiotic reduced

37
Q

How does resistance develop?

A

Bacterium which was previously susceptible obtains ability to resist activity of a particular antibiotic
only certain strains of species will be reisstane
can occur through spontaneous gene mutation

38
Q

Conjugation horizontal gene transfer

A

sharing of extra-chromosomal DNA plasmids i.e. MRSA

39
Q

Transduction horizontal gene transfer

A

insertion of DNA by bacteriophages

40
Q

Transformation horizontal gene transfer

A

picking up naked DNA

41
Q

TB resistance

A

drug unable to penetrate cell wall
low pH renders drug inactive
drug exported from cell before it reaches target
anaerobic conditions lead to dormancy
mutations in DNA repair genes
Alteration of target protein structure prevents drug recognition
alteration fo enzyme prevents conversion of pro-drug to active form

42
Q

Clostridium difficile 5Cs

A

Ciprofloxacin, Clindomucin, Cephalosporins, Co-amoxiclav, Carbapenems

Respiratory Pharmacology (17 decks)

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