Antimicrobial therapy

Question 1

The introduction of modern drugs to control infections was a medical revolution in the

Answer 1

1930s

Question 2

Antimicrobial drugs have reduced the incidence of certain infections, but,

Answer 2

Antimicrobial drugs have reduced the incidence of certain infections, but they have not eradicated infectious disease and probably never will.

Question 3

What are doctors worried about?

Answer 3

Today, doctors are worried that we are dangerously close to a postantibiotic era where the drugs we have are no longer effective.

Question 4

Goal of antimicrobial chemotherapy:

Answer 4

Administer a drug to an infected person that destroys the infective agent without harming the host’s cells

Question 5

A drug must be able to:

Answer 5

1) Be easy to administer and able to reach the infectious agent anywhere in the body
2) Be absolutely toxic to the infectious agent and absolutely nontoxic to the host
3) Remain in the body as long as needed and be safely and easily broken down and excreted

Question 6

Substances produced by the natural metabolic processes of some microorganisms

Answer 6

antibiotics

Question 7

Drugs produced entirely by chemical rxns

Answer 7

synthetic drugs

Question 8

Drugs that are chemically modified in the lab after being isolated from natural sources

Answer 8

semisynthetic drugs

Question 9

Narrow-spectrum (Limited Spectrum)

Answer 9

Antimicrobials effect against a limited array of microbial types for example, a drug effective mainly against gram-positive bacteria

Question 10

Broad-spectrum

Answer 10

antmicrobials effective against a wide variety of typed, for example, a drug effective against both gram positive and negative bacteria

Question 11

Antibiotics are common metabolic products of ______ and ________

Answer 11

Antibiotics are common metabolic products of aerobic bacteria and fungi
Produced to inhibit the growth of competing microbes in the same habitat

Question 12

Antbiotics are developed from

Answer 12

Bacteria in the genera Streptomyces and Bacillus
Molds in the genera Penicillium and Cephalosporium

Question 13

Before actual antimicrobial therapy can begin, three factors must be known:

Answer 13

-The nature of the microorganism causing the infection

-The degree of the microorganism’s susceptibility (or sensitivity) to various drugs

-The overall medical condition of the patient

Question 14

How do you do the Kirby-Bauer Technique, what is the purpose of it? What is it less effective against?

Answer 14

• Surface of an agar plate is spread with bacteria
• Small discs containing a prepared amount of antibiotic are placed on the plate
• Zone of inhibition surrounding the discs is measured and compared with a standard for each drug
• This method is less effective for anaerobic, fastidious, or slow-growing bacteria