A
Azoles, allylamines, and polyenes target fungal plasma membranes. What molecule are they specifically targeting?
Ergosterol
Which generation of cephalosporin is used to combat MRSA/ORSA strains?
Fifth generation
What category of antiviral drugs stimulate an immune response to viruses?
Interferons
Who discovered penicillin?
Alexander Fleming
What does the antiprotozoan drug, metronidazole (Flagyl) target?
Nucleic acids
What two processes does the antifungal drug flucytosine target?
DNA and RNA synthesis
1. What do plasmids carry?
2. How are they transferred?
1. Genes that encode drug- inactivation tools
2. Horizontal gene transfer
What are antimicrobial drugs?
Therapeutic compounds that kill microbes or inhibit their growth
What are 2 structures that most antifungal drugs target?
Fungal cell walls and plasma membranes
What does the abbreviation CRE stand for?
Carbapenem-resistant Enterobacterales
What are two groups of antiprotozoan drugs?
Antimalarial drugs and nonmalarial antiprotozoan drugs
When are antiviral drugs most effective?
When viruses are actively replicating
What are two key factors that have accelerated drug resistant pathogens?
Noncompliance with prescribed dosing parameters along with antimicrobial misuse
What is intrinsic resistance?
Natural resistance to antimicrobial drugs that makes certain pathogens harder to eliminate
What does the drug isoniazid target?
Mycolic acid construction in cell walls of acid-fast bacteria
What is a serious drawback that can occur when using a bactericidal drug for an endotoxin-producing Gram-negative bacterial infection?
Could trigger a dangerous surge in LPS levels in the patient
What is the therapeutic index of a drug?
The ratio of the maximum tolerated or safe dose to the minimum effective or therapeutic dose
What is the selective toxicity of a drug?
Term applied to a drug, meaning that it inhibits or kills the targeted microbe without damaging host cells
What is the difference between bacteriostatic and bactericidal antimicrobial drugs?
Bacteriostatic - preventing bacteria from growing
Bactericidal - actively killing bacteria
What do antifungal echinocandin drugs target?
Enzyme that makes beta-glucan (β-glucan), a component of the fungal cell wall
What is minimal inhibitory concentration (MIC)?
The lowest concentration of the antimicrobial drug that inhibits the microbe’s growth
What are the differences between antibiotics, synthetic antimicrobials, and semisynthetic antimicrobials?
Antibiotics - naturally occurring antimicrobial compounds
Synthetic antimicrobials - Antimicrobials that are wholly manufactured by chemical processes; they represent one avenue for making drugs that can overcome antibiotic-resistance mechanisms that naturally evolve as pathogens encounter our pharmacopeia of drugs.
Semisynthetic antimicrobials - Naturally occurring antibiotics that can be chemically modified to improve their pharmacological actions and/or stability.
What is a zone of inhibition?
Develops in disk diffusion antimicrobial susceptibility testing; a clear zone that forms around a disk infused with a test drug. Appears if the bacteria are prevented from growing
Why are human cells not affected by sulfonamide drugs?
Mammals do not make their own folic acid and therefore do not have the enzyme that these drugs target
What is antimicrobial resistance?
A situation in which a microbe, which could be a bacterium, virus, fungus, protozoan, or helminth, is not affected by a drug therapy that is intended to inhibit or eliminate the pathogen
What is drug synergism?
The combined effectiveness of two drugs that is greater than the sum of their effectiveness when used alone
What challenge are physicians facing with many antimalarial drugs, such as chloroquine and hydroxychloroquine?
Malarial pathogen resistance to these drugs is increasingly common
What is minimum bactericidal concentration (MBC)?
(MBC) The minimum concentration of the drug that kills at least 99.9 percent of the bacteria present
What are the 5 microbes that are on the CDCs urgent threat list?
1. C. difficile
2. Drug-resistant Neisseria gonorrhoeae
3. Drug-resistant Candida auris (a type of fungus)
4. Carbapenem-resistant Enterobacterales (or CRE)
5. Carbapenem-resistant Acinetobacter (CRA)
What is empiric therapy?
A standard, accepted, or typical treatment based on clinical presentation in the absence of definitive or complete clinical data; when considering antimicrobial therapies, empiric treatments are often intentionally broad spectrum and later narrowed if the causative agent is identified and found to respond to a narrow-spectrum drug
What is the difference between broad-spectrum to narrow-spectrum drugs?
Broad-spectrum drugs are effective against both Gram-negative and Gram-positive bacterial cells while Narrow-spectrum drugs target a limited range of bacteria
Why is it more difficult to develop drugs that target viruses and eukaryotes?
The collection of antibacterial drugs that we have is more extensive than the collection of drugs we have against viruses, fungi, protozoa, or helminths (worms). This is because it is difficult to develop drugs that specifically target viruses and eukaryotic pathogens such as fungi, protozoa, and helminths without inflicting collateral damage on our own cells.
When talking about drugs, what is half-life?
The time it takes for half of a dose to be eliminated or deactivated by the body—often by the kidneys or liver, as already noted
What is acquired resistance?
A form of antimicrobial drug resistance that develops due to genetic mutation or, in the case of bacteria, a form of antimicrobial drug resistance that develops when drug resistance genes are transferred or shared via horizontal gene transfer events such as conjugation and transformation
What are superbugs?
A name for resistant microbes; derives from the point that resistant microbes remain unaffected by the administered antimicrobial therapy and may readily increase their numbers in the patient and cause a superinfection that is difficult to treat