Brainscape's Knowledge GenomeTM

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


See full index

Pathophysiology > 9.1 Infection and Antimicrobials > Flashcards

9.1 Infection and Antimicrobials Flashcards

1
Q

Normal Microbial Flora

A
  • Protect host by occupying space and consuming nutrients inhibiting pathogens from proliferation
  • Pathogens thrive if normal flora is supresssed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Antibiotic Therapy

A
  • Necessary when host defense mechanisms are not adequate to ward off infection
  • 1/3 - 1/2 hospitalized patients are treated with antimicrobials
  • Used to treat/prevent infections caused by pathogens
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Antimicrobial/Antibiotic

A

Antibiotic - Produced from one microbe that has the ability to harm other microbes.
Antimicrobial - Any agent capable of suppressing or killing microorganisms.
Chemotherapy - Use of chemical agents against invading organisms.

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

Antibacterial Drugs

A
  • Can be broad or narrow spectrum

- Classified by kinds of organisms they are effective against

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

Antibacterial

A
  • Bacterial infections

staphylococcus, streptococcus, gonorrhea

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

Antiviral

A
  • Used for viral infections

Chicken pox, influenza, HIV

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

Antifungal

A

Used for fungal infections

Athletes foot, oral thrush, vaginal yeast, mucormycotic

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

Antiprotozoal

A
  • Used for protozoal infections (parasite)

Malaria, amoebic dysentery

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

Anthelminthic Agent

A

Parasitic Infections

Tape worm, schistosomiasis

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

Antimicrobial Drug Classifications

A
  • They are classified by their mechanism of action or what part of the target the drug acts on
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Ribosome

A

Aminoglycosides, Macrolides, Ketolides, Tetracyclines, Linezolid, and Quinupristin/Dalfopristin

These drugs bind to ribosomes and inhibit production of essential proteins (Inhibition of Protein Synthesis)

Aminoglycosides (lethal)
Tetracyclines (non-lethal)

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

DNA

A

Fluoroquinolones - Inhibit DNA gyrase, enzyme required for reproduction (Inhibition of Nucleic Acid Synthesis)

  • Inhibits DNA/RNA synthesis which affects transcription and replication of the bacteria.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Cell Wall

A

Penicillin, cephalosporin, vancomycin

  • Inhibit formation of cell wall (inhibition of bacterial cell wall synthesis)
  • Drugs produce defective cell wall which destroys microorganism.
  • Fluid is drawn into cell until cell bursts.
  • Immune system cleans debris and fights remaining infection.
  • Works best when cell is replicating
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Cell Membrane

A
  • Inhibition of viral replication and disruption of cell wall permeability
  • Inhibition of viral replication prevents virus entry into host cell
  • Polymyxins disrupt cell wall permeability by binding to lipopolysaccharides.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Folic Acid

A

Sulfonamides block synthesis of components necessary for cell metabolism and growth
(Inhibition of metabolic pathways (Antimetabolites))

  • Inhibition of folic acid and synthesis, which is essential for survival of pathogen.
  • Human cells don’t need this because they get folic acid through dietary resources
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Bacteriostatic Drugs

A

INHIBITS BACTERIA

  • Reversible if drug is removed unless host mechanisms have eradicated the organism
  • Sulfonamides, erythromycin, tetracyclines
17
Q

Bactericidal Drugs

A

Antibiotics that kill bacteria

  • Less dependence on bodies defense mechanisms.
  • Penicillin, cephalosporins, aminoglycosides.
18
Q

Selective Toxicity

A
  • Ability to suppress/kill infecting microbe without injury to host.
  • Achievable because cellular chemistry of mammals and microbes differ
  • Disruption of cell walls, inhibition of enzymes unique to bacteria, disruption of bacterial protein synthesis.
19
Q

Antimicrobial Resistance

A
  • Pathogens change over time and stop responding to medications
  • Infections caused by resistant pathogens require more toxic and expensive medications.
  • Microbes acquire resistance through spontaneous mutations / random changes in microbial DNA transferred from 1 bacteria to another.
  • Bodies normal flora can contribute to this.
20
Q

Antimicrobial Resistance

A
  • The more antibiotics used, the faster drug resistant microbes emerge.
  • They grow and multiply while normal flora are suppressed by antimicrobials
  • They emerge during or after broad spectrum therapy that suppress normal flora
  • Interruption/inadequate use of antimicrobial treatment also promote this.
  • Education is important to use antimicrobials exactly as ordered
21
Q

Antibiotic Resistant Microbes

A
  • Methicillin-Resistant Staphylococcus Aureus (MRSA)
  • Penicillin-Resistant Streptococcus Pneumoniae
  • Vancomycin-Resistant Enterococci (VRE)
  • Multi-drug Resistant Enterococci (MDR-TB)
  • Extensively Drug-Resistant TB (XDR-TB)
  • Enterococcus Faecalis and Faecium
  • Clostridium Difficile (C-Diff)
22
Q

SuperInfection

A
  • Occurs during or after treatment of earlier infection, especially infection treated with broad spectrum antibiotics.
  • Usually caused by drug resistant microbes
  • CDIFF, MRSA, Oral/Vaginal Candida Infection
23
Q

Prevention of Antimicrobial Resistance

A
  • Vaccinations - Prevent infection in the first place
  • Remove Catheters (Indwelling such as urinary and IV)
  • Target the pathogen (obtain cultures and sensitivities to identify the bacteria and target the specific bacteria)
  • Use infectious disease experts to guide treatment
24
Q

Use antimicrobials wisely

A
  • Practice antimicrobial control
  • Use local data
  • Treat infection not contamination
    (Infection is presence of pathogen, Contamination is unintended infectious material into area)
  • Treat infection not colonization
    (Presence of pathogen without illness or symptoms)
  • Know when to say no to Vanco
    (Vancomycin - attacks gram positive bacteria. Limit use if there is no evidence of gram positive bacteria)
  • Stop treatment when infection is cured or unlikely to be cured
25
Q

Prevent Transmission

A

Isolate Pathogen - Standard precautions and isolation

Break chain of contagion - Wash Hands, appropriate PPE

26
Q

Infectious Disease

A
  • Presence of pathogens and clinical signs/symptoms

- Spread via direct contact or contaminated hands, food, water and objects

27
Q

Opportunistic Pathogens

A
  • Caused by normal flora that are non-pathogenic however become pathogenic with impaired defense mechanisms
  • Situations include burns, cancer, HIV, indwelling IV/catheter, patients with antibiotics, corticosteroid therapy
  • Bacterial infections are serious and can be life threatening.
28
Q

Antimicrobial Therapy Principles

A
  • Goal is to eliminate causative microorganism and return patient to full health
  • Antimicrobials are the most frequent used medication worldwide
  • Overuse leads to adverse effects, increased cost, increased drug resistant drugs, multi drug resistant infections
29
Q

Therapy Use Guidelines

A
  • Use older, cost-effective drug if it meets criteria
  • Combination therapy of antimicrobials to treat infections caused by multiple microbes nosocomial infections, and serious infections
  • May be given orally or IV dependent on patients condition, location, severity of infection, patients ability to take oral medication
30
Q

Considerations when selecting Antimicrobial

A
  • Match the drug with the bug.
  • Initial therapy of severe infections provide wide coverage,
  • Prophylactic use of antimicrobials 30-50% of use. Prevents infection before it happens.
31
Q

Common Misuse of Antimicrobials

A
  • Untreatable infections (colds, chicken pox, mumps)
  • Improper dosage
  • Treatment without adequate microbe information except in life threatening conditions
32
Q

Monitoring Antimicrobial Therapy

A
  • Monitor serum peak and trough levels. Hepatic and Renal Function, CBC,
  • Duration of therapy depends on reason for use. Prophylaxis may be single dose,
  • Acute infection may be 7-10 days or until patient is afebrile and asymptomatic for 48-72 hours
33
Q

Beta-Lactum Antibacterials

A
  • Work by inhibiting synthesis of bacterial wall

- Penicillin, Cephalosporins, Monobactams

34
Q

Bacteria

A
  • Cell walls and membranes either gram positive or gram negative
  • Aerobic, Anaerobic, Facultative (adaptive)
    Cocci - Round
    Bacilli - Rod
    Spirochetes - Corkscrew shaped
35
Q

Adaptive mechanism of bacteria

A
  • Some create mucous membranes or capsules that discourage phagocytosis by host WBC’s.
  • Some secrete toxins which damage host neutrophils and macrophages
  • Can survive and reproduce within phagocytes
  • Enzymes that allow bacteria to escape detection
36
Q

Fungal Infections

A

2 types - Yeast and Mold
Yeast - Single celled organism and mold with long, hollow branching filaments called hyphae
Fungi - Produce disease in humans only if they grow at temperature of infected body.
Yeast is usually on skin, mucous membranes, GI tract

37
Q

Select Opportunistic Fungal Infections

A

Aspergillosis - Found in soil, water, decaying vegetation. Airborne
Candidiasis - Yeast like fungus almost always present in mouth, skin, intestines, vagina
Cryptococcosis - Most serious fungal infection in immunocompromised patients.
Mucormycotic - Infection in sinuses, brain, lungs, caused by Mucor or Rhizopus

38
Q

Non-Opportunistic Fungal Infection

A

Blastomycosis - Chronic infection characterized by granulomatous and suppurative lesions
Coccidioidomycosis - Primary disease of lungs, common in southwest US and northwest Mexico
Dermatophytic Infection - Ringworm/Tinea caused by mold like fungi called dermatophytes.
Histoplasmosis - Fungal infection that effects lungs or other organs of dissemination. Acquired by breathing in fungal spores.

39
Q

Virus

A
  • Genetic material inside protein coating
  • Cannot reproduce without assistance of host
  • Insert genetic material into host and utilize human cell to reproduce viral particles
  • Antiviral drugs inhibit viral reproduction but do not eliminate virus from tissues.
  • Difficult to suppress viral replication without significantly harming host
  • Suppress biochemical process unique to viral reproduction.

Pathophysiology (18 decks)

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