Brainscape's Knowledge GenomeTM

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


See full index

Microbio > Anti microbial therapy > Flashcards

Anti microbial therapy Flashcards

1
Q

Antimicrobial agent

A

a special group of chemotherapeutic agents used to treat diseases caused by microbes

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

chemotherapeutic agent

A

any chemical substance used in medical practice (drugs)

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

Spectrum of activity

A

the range of different microbes against which an antimicrobial agent acts

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

Broad spectrum

A

agents that are effective against a great number of microorganisms from a wide range of taxonomic groups, including both gram-positive and gram–negative bacteria

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

Narrow spectrum

A

agents that are effective against only a small number of microorganisms or a single taxonomic group

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

5 major modes of action that antibiotics have on bacterial cells

A
  • inhibition of cell wall synthesis
  • disruption of cell membrane function
  • inhibition of protein sythesis
  • inhibition of nucleic acid synthesis
  • action as antimetabolites
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Antibiotics that inhibit cell wall synthesis

A

penicillin (natural), penicillin (semisynthetic), cephalosporins, carbapenems, bacitracin

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

Natural penicillin

A

treats a wide variety of infections, mostly gram positive bacteria

has relatively few side affects but allergies

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

Semisynthetic Penicillin

A

treats infections that are resistant to natural penicillin

few side effects as well

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

Cephalosporins

A

treats a wide variety of infections when allergy or toxicity makes other agents unsuitable

relatively non toxic, but can lead to superinfections

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

carbapenems

A

mixed infections, nosocomial infections, infections of unknown etiology

allergic reations, superinfections, seizures, gastrointestinal disturbances

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

Bacitracin

A

treats skin infections

internal use is toxic to the kidneys

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

Antibiotics that disrupt cell membrane function

A

polymyxins and tyrocidins

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

Polymyxins

A

treats skin infections

internal use can be highly toxic

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

Tyrocidins

A

treats skin infections cause by gram positive cocci

internal use can be highly toxic

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

Antibiotics that inhibit protein synthesis

A

streptomycin, gentamicin and other aminoglycosides, tetracyclines, chloramphenicol, erthromycin

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

Streptomycin

A

treats tuberculosis

can damage kidneys and the inner ear

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

Gentamicin and other aminoglycosides

A

treats antibiotic resistant and hospital acquired infections

can cause varying degrees of kidney and inner ear damage

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

chloramphenicol

A

treats a broad spectrum of bacterial infections, brain abscesses, and penicillin resistant infections

can damage bone marrow and cause aplastic anemia

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

tetracyclines

A

treats a broad spectrum of bacterial infections and some fungal infections

can stain teeth, cause gastrointestinal symptoms, and can lead to super infections

21
Q

Erythromycin

A

treats gram positive bacterial infections, some penicillin resistant infections, and legionnaires’ disease

22
Q

Antibiotics that inhibit nucleic acid synthesis

A

rifampin and quinolones

23
Q

Rifampin

A

treats tuberculosis and to eliminate meningocci from the naspharynx

can cause bright orange or red urine, saliva, tears, and skin; liver damage; and many disorders when used with other agents

24
Q

Quinolones

A

Treats UTI’s, traveller’s diarreah, and effective against many drug resistant organisms

can cause nausea, headaches and other nervous system disturbances

25
Q

Antibiotics that act as anitmetabolites

A

sulfonamides, isoniazid, ethambutol, and nitrofurantoin

26
Q

Sulfonamides

A

treats some kinds of meningitis and suppresses intestinal flora before colon surgery

earlier forms caused kidney damage, however current ones do not

27
Q

Isoniazids

A

treats tuberculosis

can cause pyridoxine deficiency

28
Q

Ethambutol

A

Treats tuberculosis

may cause pyridoxine deficiency

29
Q

Nitrofurantonin

A

treats UTI’s

can cause nausea and vomiting

30
Q

Common side effects of antimicrobial agents on include

A

toxicity, allergy, and disruption of normal microflora

31
Q

superinfection

A

invasion by replacement microflora

32
Q

5 mechanisms of resistance in bacteria

A
  • Alteration of targets
  • Alteration of membrane permeability
  • development of enzymes
  • alteration of an enzyme
  • alteration of a metabolic pathway
33
Q
  1. Alteration of targets
A

mutation alters DNA such that the protein produced or targeted is modified. Antimicrobial agents can no longer bind to the target

34
Q
  1. Alteration of Membrane Permability
A

this occurs when new genetic info changes the nature of proteins in the membrane. such alterations change membrane transport systems or pores in the membrane so that an antimicrobial agent can no longer cross the membrane

35
Q
  1. Development of Enzymes
A

this common cause of resistance can destroy or inactivate antimicrobial agents. The most common enzyme of this type is called B-lactamase

36
Q

B-lactamase

A

exist in various bacteria, and they are capable of breaking the B-lactam ring in penicillins and some cephalosporins

37
Q
  1. Alteration of an enzyme
A

allows a formerly inhibited reaction to occur

38
Q
  1. alteration of a metabolic pathway
A

bypasses a reaction inhibited by an antimicrobial agent that occurs in other sulfonamide-resistant bacteria

39
Q

What happens when a person does not finish their prescription of antibiotics

A

if this occurs, a more serious infection can develop. By not finishing the antibiotic you leave the most resistant organisms alive, allowing them to multiply leading to an infection that will be difficulty or impossible to cure using the same antibiotic

40
Q

Kirby - Bauer Method

A

a standard quantity of the causative organism is uniformly spread over an agar plate. Then several filter paper disks impregnated with specific concentrations of selected chemotherapeutic agents are placed on the agar surface. Finally, the culture with the antibiotic disks is incubated. Clear areas, called zones of inhibition appear on the agar around disks where the agents inhibit the organism. The size of a zone of inhibition is not necessarily a measure of the degree of inhibition because of differences in the diffusion rates of chemotherapeutic agents. One can measure the zones and look at a chart to see whether the drugs are sensitive, moderately sensitive, or resistant to the drug

41
Q

Dilution method

A

a standardized microdilution plate with shallow wells that contain increasing dilutions (decreasing concentrations) of selected antibiotics in a broth is inocultaed with a test bacterium. The lowest concentration that prevents growth is known as the minimum inhibitory concentration (MIC) for a particular agent acting on a specific microorganism.

42
Q

Minimum Bactericidal Concentration (MBC) test

A

Samples from tubes that show no growth but that might contain inhibited organisms can be used to inoculate broth that contains no chemotheraputic agent. in this test, the lowest concentration of the chemotheraputic agent that yields no growth following a second inocultaion, or subculturing, is the MBC

43
Q

Characteristics of an ideal antimicrobial agent

A
  • solubility in body fluids
  • selective toxicity
  • toxicity is not easily altered
  • non-allergenic
  • stability
  • Resistance by microorganisms not easily acquired
  • long shelf life
  • reasonable cost
44
Q

Why is it so hard to produce agents against fungi, viral, protozoan, and helminthic organisms?

A

Treatment of worm infections and viruses are especially difficult because what damages the parasite will also damage the host. Because fungi are eukaryotes and thus similar to human cells, antifungal treatment often causes toxic side effects.

45
Q

Antifungal agents

A

clotrimazole, miconazole, amphotericin B, nystatin, griseofulvin, flucytosine

46
Q

Antiviral agents

A

idoxuridine, ganciclovir, vidarabine, ribavirin, acyclovir, amantadine, AZT

47
Q

Antiprotozoan agents

A

Quinine, chloroquine, primaquine, pyrimethamine, metronidazole

48
Q

Antihelminthic Agents

A

niclosamide, piperazine, mebendazole, Ivermectin

Microbio (10 decks)

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