CH 9 ANTIBIOTICS NUR187 EXAM QUESTIONS AND ANSWERS
WITH COMPLETE SOLUTIONS VERIFIED LATEST UPDATE
(?) chemical that inhibits the growth of specific bacteria or causes the death of
susceptible bacteria
antibiotic
(?) bacteria that have only a thin layer of peptidoglycan, making them less likely
to absorb stain or become decolorized by alcohol; these bacteria are frequently
associated with infections of the genitourinary or gastrointestinal (GI) tract
gram-negative
(?) bacteria that have cell walls with more peptidoglycan layers, which absorb
more stain or resist decolorization with alcohol during preliminary identification;
these bacteria are frequently associated with infections of the respiratory tract
and soft tissues
gram-positive
CARBAPENEMS
ertapenem
CEPHALOSPORINS
First Generation
cefazolin
FLUOROQUINOLONES
ciprofloxacin
,PENICILLINS AND PENICILLINASE-RESISTANT ANTIBIOTICS
Natural Penicillins
penicillin V
TETRACYCLINES
tetracycline
Macrolides
erythromycin
Many new bacteria appear each year, and researchers are challenged to develop
new antibiotics— chemicals that inhibit specific bacteria—to deal with each new
threat. Antibiotics are made in three ways: by living microorganisms, by synthetic
manufacture, and in some cases through genetic engineering. Antibiotics may
either be bacteriostatic (inhibiting the growth of bacteria) or bactericidal (killing
bacteria directly), although several antibiotics are both bactericidal and
bacteriostatic, depending on the concentration of the particular drug and the
bacteria it is treating.
This chapter discusses the major classes of antibiotics: aminoglycosides,
carbapenems, cephalosporins, fluoroquinolones, penicillins and penicillinase-
resistant drugs, sulfonamides, tetracyclines, and the disease-specific
antimycobacterials, including the antitubercular and leprostatic drugs. Antibiotics
that do not fit into the large antibiotic classes include lincosamides,
lipoglycopeptides, macrolides, monobactams, and oxazolidinones. Figures 9.1
and 9.2 show sites of cellular action of these classes of antibiotics.
,Fever, lethargy, elevated white blood cell count, and the classic signs of
inflammation (e.g., redness, swelling, heat, and pain) all indicate that the body is
responding to an invader. The body becomes the host for the bacteria and
supplies proteins and enzymes the bacteria need for reproduction. Unchallenged,
the invading bacteria can multiply and send out other bacteria to further invade
tissue.
The goal of antibiotic therapy is to decrease the population of invading bacteria
to a point at which the human inflammatory/immune system can effectively deal
with the pathogen. To determine which antibiotic will effectively interfere with the
specific proteins or enzyme systems for treatment of a specific infection, the
causative organism should be identified through a culture. Sensitivity testing is
also done to determine the antibiotic to which that particular organism is most
sensitive (i.e., which antibiotic best kills or controls the bacteria). Often the
specific infectious pathogen cannot be identified, and these infections are treated
empirically to cover the most likely pathogens for that type of infection.
Gram staining is a technique that can be used to categorize types of bacteria
based on their types of cell wall.
Gram-positive bacteria have cell walls with more peptidoglycan layers, which
retain more dye, or Gram stain, and resist decolorization with alcohol during
culture and sensitivity testing. Gram-positive bacteria are commonly associated
with infections of the respiratory tract and soft tissues. An example of a gram-
positive bacterium is Streptococcus pneumoniae, a common cause of
pneumonia.
, gram-negative bacteria have only a thin layer of peptidoglycan, making them
more likely to lose a stain or become decolorized by alcohol. These bacteria are
frequently associated with infections of the genitourinary (GU) or GI tract. An
example of a gram-negative bacterium is Escherichia coli, a common cause of
cystitis.
Aerobic bacteria depend on oxygen for survival, whereas anaerobic bacteria (e.g.,
those bacteria associated with gangrene) do not use oxygen.
If culture and sensitivity testing is not possible, either because the source of the
infection is not identifiable or because the patient is too sick to wait for test
results to determine the best treatment, clinicians attempt to administer a drug
with a broad spectrum of activity against the organisms with the highest
probability of causing the infection. Antibiotics that interfere with a biochemical
reaction common to many organisms are known as broad-spectrum antibiotics.
These drugs are often given at the beginning of treatment until the exact
organism and sensitivity can be established. Human cells have many of the same
properties as bacterial cells and can be affected in much the same way, so
damage may occur to the human cells, as well as to the bacterial cells.
In some cases, antibiotics are given in combination because they are synergistic,
meaning their combined effect is greater, or they are able to treat a more severe
infection, when given together than when given individually.
Older Adults
In many instances, older adults do not present with the same signs and
symptoms of infections as other patients. For example, a urinary tract infection
WITH COMPLETE SOLUTIONS VERIFIED LATEST UPDATE
(?) chemical that inhibits the growth of specific bacteria or causes the death of
susceptible bacteria
antibiotic
(?) bacteria that have only a thin layer of peptidoglycan, making them less likely
to absorb stain or become decolorized by alcohol; these bacteria are frequently
associated with infections of the genitourinary or gastrointestinal (GI) tract
gram-negative
(?) bacteria that have cell walls with more peptidoglycan layers, which absorb
more stain or resist decolorization with alcohol during preliminary identification;
these bacteria are frequently associated with infections of the respiratory tract
and soft tissues
gram-positive
CARBAPENEMS
ertapenem
CEPHALOSPORINS
First Generation
cefazolin
FLUOROQUINOLONES
ciprofloxacin
,PENICILLINS AND PENICILLINASE-RESISTANT ANTIBIOTICS
Natural Penicillins
penicillin V
TETRACYCLINES
tetracycline
Macrolides
erythromycin
Many new bacteria appear each year, and researchers are challenged to develop
new antibiotics— chemicals that inhibit specific bacteria—to deal with each new
threat. Antibiotics are made in three ways: by living microorganisms, by synthetic
manufacture, and in some cases through genetic engineering. Antibiotics may
either be bacteriostatic (inhibiting the growth of bacteria) or bactericidal (killing
bacteria directly), although several antibiotics are both bactericidal and
bacteriostatic, depending on the concentration of the particular drug and the
bacteria it is treating.
This chapter discusses the major classes of antibiotics: aminoglycosides,
carbapenems, cephalosporins, fluoroquinolones, penicillins and penicillinase-
resistant drugs, sulfonamides, tetracyclines, and the disease-specific
antimycobacterials, including the antitubercular and leprostatic drugs. Antibiotics
that do not fit into the large antibiotic classes include lincosamides,
lipoglycopeptides, macrolides, monobactams, and oxazolidinones. Figures 9.1
and 9.2 show sites of cellular action of these classes of antibiotics.
,Fever, lethargy, elevated white blood cell count, and the classic signs of
inflammation (e.g., redness, swelling, heat, and pain) all indicate that the body is
responding to an invader. The body becomes the host for the bacteria and
supplies proteins and enzymes the bacteria need for reproduction. Unchallenged,
the invading bacteria can multiply and send out other bacteria to further invade
tissue.
The goal of antibiotic therapy is to decrease the population of invading bacteria
to a point at which the human inflammatory/immune system can effectively deal
with the pathogen. To determine which antibiotic will effectively interfere with the
specific proteins or enzyme systems for treatment of a specific infection, the
causative organism should be identified through a culture. Sensitivity testing is
also done to determine the antibiotic to which that particular organism is most
sensitive (i.e., which antibiotic best kills or controls the bacteria). Often the
specific infectious pathogen cannot be identified, and these infections are treated
empirically to cover the most likely pathogens for that type of infection.
Gram staining is a technique that can be used to categorize types of bacteria
based on their types of cell wall.
Gram-positive bacteria have cell walls with more peptidoglycan layers, which
retain more dye, or Gram stain, and resist decolorization with alcohol during
culture and sensitivity testing. Gram-positive bacteria are commonly associated
with infections of the respiratory tract and soft tissues. An example of a gram-
positive bacterium is Streptococcus pneumoniae, a common cause of
pneumonia.
, gram-negative bacteria have only a thin layer of peptidoglycan, making them
more likely to lose a stain or become decolorized by alcohol. These bacteria are
frequently associated with infections of the genitourinary (GU) or GI tract. An
example of a gram-negative bacterium is Escherichia coli, a common cause of
cystitis.
Aerobic bacteria depend on oxygen for survival, whereas anaerobic bacteria (e.g.,
those bacteria associated with gangrene) do not use oxygen.
If culture and sensitivity testing is not possible, either because the source of the
infection is not identifiable or because the patient is too sick to wait for test
results to determine the best treatment, clinicians attempt to administer a drug
with a broad spectrum of activity against the organisms with the highest
probability of causing the infection. Antibiotics that interfere with a biochemical
reaction common to many organisms are known as broad-spectrum antibiotics.
These drugs are often given at the beginning of treatment until the exact
organism and sensitivity can be established. Human cells have many of the same
properties as bacterial cells and can be affected in much the same way, so
damage may occur to the human cells, as well as to the bacterial cells.
In some cases, antibiotics are given in combination because they are synergistic,
meaning their combined effect is greater, or they are able to treat a more severe
infection, when given together than when given individually.
Older Adults
In many instances, older adults do not present with the same signs and
symptoms of infections as other patients. For example, a urinary tract infection
