Untitled Quiz

Questions and Answers

What layer does gram-positive bacteria have?

a thick layer of peptidoglycan

What distinguishing feature does gram-negative bacteria have?

a thin layer of peptidoglycan plus an outer membrane

What type of bacteria are Staphylococcus aureus and Streptococcus/Enterococcus?

gram positive

What are examples of gram-negative bacteria?

E. coli, Klebsiella, Proteus, Pseudomonas Signup and view all the answers

Empiric therapy is based on what?

"educated guess" Signup and view all the answers

What is prophylactic therapy?

antibiotics used to prevent anticipated risks/infections Signup and view all the answers

What is a superinfection?

an infection occurring after or on top of originally treated infection Signup and view all the answers

What is a gram stain used for?

to look at microorganisms under a microscope at stained cells Signup and view all the answers

What does culture refer to in microbiology?

growing bacteria in the lab and testing different antibiotics Signup and view all the answers

What is measured in serology?

titers or antibodies Signup and view all the answers

What does an antibody titer indicate?

the antibody level in the blood Signup and view all the answers

What does CBC stand for?

complete blood count Signup and view all the answers

Culture types include throat, wound, urine, sputum, ______.

blood Signup and view all the answers

What are antimicrobials?

drugs that prevent or treat infections from pathogens Signup and view all the answers

What do bactericidal drugs do?

kill bacteria directly Signup and view all the answers

What do bacteriostatic drugs do?

prevent bacteria from dividing or inhibit their growth Signup and view all the answers

What does aerobic mean?

grow and live in presence of oxygen Signup and view all the answers

What are examples of aerobic bacteria?

Staphylococcus and Streptococcus Signup and view all the answers

What does anaerobic mean?

cannot grow in the presence of oxygen Signup and view all the answers

What is a community-acquired infection?

less severe and easier to treat Signup and view all the answers

What is the issue with bacterial resistance?

Bacteria develop the ability to block antibiotics Signup and view all the answers

What causes resistance?

widespread use of antimicrobial drugs Signup and view all the answers

What defines an opportunistic host?

compromised immune system Signup and view all the answers

What is essential in client history for antibiotic therapy?

allergies and previous drug reactions Signup and view all the answers

List some antibiotics.

sulfonamides, penicillins, cephalosporins, macrolides, fluoroquinolones, aminoglycosides, tetracyclines Signup and view all the answers

What do sulfonamides do?

inhibit the growth of bacteria Signup and view all the answers

In which context are sulfonamides usually used?

combination drugs Signup and view all the answers

What are examples of sulfonamides?

Trimethoprim/sulfamethoxazole Signup and view all the answers

What are the uses of sulfonamides?

broad spectrum against gram-negative and gram-positive organisms Signup and view all the answers

Why are sulfonamides effective for kidney infections?

they achieve a high concentration in the kidneys Signup and view all the answers

What is a downside of using sulfonamides?

organisms become more resistant Signup and view all the answers

Who may be given sulfa drugs prophylactically?

HIV patients with pneumocystis carinii Signup and view all the answers

List some contraindications with sulfonamides.

drug allergy to sulfa, use of thiazide and loop diuretics Signup and view all the answers

What are the most common adverse effects of sulfa drugs?

cutaneous reactions Signup and view all the answers

What are other adverse effects of sulfa drugs?

photosensitivity reactions Signup and view all the answers

What does indication mean in medical terms?

the basis for initiation of treatment or diagnostic test Signup and view all the answers

What are the four major drug classifications of Beta-Lactam antibiotics?

penicillins, cephalosporins, carbapenems, monobactams Signup and view all the answers

From where is penicillin derived?

mold fungi Signup and view all the answers

How can 1st generation penicillins be administered?

IM or IV Signup and view all the answers

What is a notable feature of newer penicillins?

increased gastric acid stability Signup and view all the answers

Where does penicillin distribute effectively in the body?

most bodily fluids Signup and view all the answers

What action does penicillin perform?

bactericidal by binding to bacterial wall Signup and view all the answers

What type of bacteria does penicillin primarily kill?

gram-positive bacteria Signup and view all the answers

What is the most common adverse reaction to penicillin?

GI issues such as diarrhea Signup and view all the answers

What are other adverse reactions to penicillins?

urticaria, pruritus, angioedema Signup and view all the answers

What are the signs of anaphylaxis?

loss of consciousness, hives, swelling of tongue Signup and view all the answers

What are examples of combination penicillin drugs?

Unasyn, Augmentin, Timentin, Zosyn Signup and view all the answers

What is ampicillin classified as?

synthetic penicillin Signup and view all the answers

What is ampicillin effective against?

E. coli, Proteus, Salmonella, Shigella Signup and view all the answers

What bacteria is ampicillin not effective against?

staphylococci and gonococci Signup and view all the answers

What action does ampicillin have?

bactericidal by binding to bacterial wall Signup and view all the answers

For which organisms is ampicillin used?

gram-positive organisms: Streptococcus, Enterococcus, Staphylococcus Signup and view all the answers

What should you ask clients regarding ampicillin?

oral contraceptive use Signup and view all the answers

What are the trade names for amoxicillin?

Amoxil, Trimox, Wymox Signup and view all the answers

What is amoxicillin used for?

skin infections, otitis media, sinusitis, respiratory infections Signup and view all the answers

What is the oral bioavailability of amoxicillin?

readily absorbed and reaches therapeutic levels rapidly Signup and view all the answers

Who needs to take amoxicillin prior to dental work?

clients with total knee or hip replacement, heart valve replacement Signup and view all the answers

What are cephalosporins derived from?

fungus Signup and view all the answers

What type of bacteria are cephalosporins used against?

gram-negative bacteria Signup and view all the answers

How well are cephalosporins absorbed?

widely absorbed and distributed in many bodily fluids Signup and view all the answers

What level of therapeutic penetration do 1st generation cephalosporins achieve in CSF?

do not reach therapeutic levels Signup and view all the answers

What is the action of first-generation cephalosporins?

bactericidal by binding to bacterial cell wall Signup and view all the answers

What is a common first-generation cephalosporin used for skin infections?

Keflex Signup and view all the answers

What is Ancef often ordered for?

preoperatively in orthopedic procedures Signup and view all the answers

What should be noted about Keflex and food?

may be taken with or without food Signup and view all the answers

How is Keflex distributed in the body?

in low concentrations; may cross placenta or enter breast milk Signup and view all the answers

Is Keflex excreted by the kidneys?

yes, entirely Signup and view all the answers

Cefazolin is what generation cephalosporin?

first generation Signup and view all the answers

Is cefazolin well absorbed following IM or IV administration?

yes, well absorbed Signup and view all the answers

Does cefazolin penetrate CSF well?

minimal CSF penetration Signup and view all the answers

How is cefazolin excreted?

excreted by kidneys Signup and view all the answers

What infections is cefazolin used for?

UTIs, bone and skin infections, endocarditis Signup and view all the answers

How are second-generation cephalosporins active against bacteria?

more active against some gram-negative and anaerobic Signup and view all the answers

What absorption level do second-generation cephalosporins achieve in CSF?

poor but adequate for meningitis Signup and view all the answers

What do third-generation cephalosporins increase activity against?

increased activity against gram-negative pathogens Signup and view all the answers

What is the action of second-generation cephalosporins?

bactericidal by binding to cell wall Signup and view all the answers

How well do third-generation cephalosporins absorb in CSF?

better than first two generations Signup and view all the answers

If a client is allergic to penicillin, what is the risk with cephalosporins?

1 to 18% chance of being allergic Signup and view all the answers

What kind of action do carbapenems have?

very broad antibacterial action Signup and view all the answers

Which carbapenem is used in the treatment of bacterial meningitis?

meropenem Signup and view all the answers

For what are carbapenems often used?

complicated body cavity and connective tissue infections Signup and view all the answers

Name two new drugs in the macrolide classification.

azithromycin and clarithromycin Signup and view all the answers

What are the four main macrolides?

azithromycin, clarithromycin, dirithromycin, erythromycin Signup and view all the answers

What is a key feature of macrolides compared to other antibiotics?

lower GI effects Signup and view all the answers

What is the action of macrolides?

inhibit protein synthesis in susceptible bacteria Signup and view all the answers

What is a contraindication for macrolides?

drug allergy Signup and view all the answers

What are fluoroquinolones used for?

treatment of chronic infections or deep abdominal infections Signup and view all the answers

What is the only drug in the ketaloids classification?

telithromycin Signup and view all the answers

What is vancomycin primarily used for?

MRSA infections resistant to fluoroquinolones Signup and view all the answers

What can clindamycin or Cleocin cause?

pseudomembranous colitis Signup and view all the answers

What does herpes simplex virus type 1 cause?

cold sore Signup and view all the answers

Study Notes

Bacteria Classification

Gram Positive Bacteria: Characterized by a thick layer of peptidoglycan in the cell wall.
Gram Negative Bacteria: Have a thin peptidoglycan layer and an outer membrane.
Examples of Gram Positive: Staphylococcus aureus, Streptococcus, Enterococci.
Examples of Gram Negative: Escherichia coli, Klebsiella, Proteus, Pseudomonas.

Antibiotic Therapy

Empiric Therapy: Initiated based on educated guesses regarding infection sources, preventing delays before culture results.
Prophylactic Therapy: Antibiotics administered to prevent infections, e.g., malaria pills for travelers.
Superinfection: Occurs when a new infection arises after an initial infection due to antibiotic use, fostering overgrowth of resistant bacteria.

Diagnostic Procedures

Gram Stain: Microscopic examination of stained microbial cells.
Culture: Laboratory method for growing bacteria and testing antibiotic efficacy.
Serology: Measurement of antibodies in the blood, useful for diagnosing infections.

Antibody Measurement

Antibody Titer: Indicates exposure to antigens; assesses past infections and immunity status.
Uses of Titer Measurement: Determine immune response strength, need for booster immunization, and past infections assessment.

White Blood Cell Count (CBC)

Monitoring WBC count helps identify infections; elevated levels indicate immune response.

Culture Types

Various culture types include throat, wound, urine, sputum, and blood; often collected before starting antibiotics.

Antimicrobials

Definition: Drugs used to prevent or treat infections caused by pathogens.
Bactericidal Drugs: Directly kill bacteria.
Bacteriostatic Drugs: Inhibit bacterial growth without killing.

Aerobic vs. Anaerobic Bacteria

Aerobic Bacteria: Thrive in the presence of oxygen (e.g., Staphylococcus, Streptococcus).
Anaerobic Bacteria: Cannot grow in the presence of oxygen; often found in deep wounds, characterized by bad-smelling pus.

Infection Types

Community-Acquired Infections: Generally less severe, easier to treat, with increasing drug resistance (e.g., MRSA).
Nosocomial Infections: More severe, challenging to treat due to drug-resistant strains.

Antibiotic Resistance

Causes: Overuse of antibiotics, inadequate treatment, host conditions, and certain bacteria types exhibit higher resistance.

At-Risk Populations

Opportunistic Hosts: Groups with compromised immune systems include infants, the elderly, cancer patients, and those with HIV.

Patient Assessment

Consider patient allergies, prior drug reactions, renal/liver function, and responses to previous antibiotic therapy.

Classification of Antibiotics

Major classes include sulfonamides, penicillins, cephalosporins, macrolides, fluoroquinolones, aminoglycosides, and tetracyclines.

Sulfonamides (Sulfa Drugs)

Action: Bacteriostatic; inhibits bacterial folic acid synthesis.
Indications: Broad-spectrum effectiveness against various bacteria.
Common Uses: Particularly useful for kidney infections.

Penicillins

Derived from mold fungi, effective in targeting gram-positive bacteria.
Forms: Can be administered intramuscularly (IM) or intravenously (IV).
Adverse Effects: GI disturbances, allergic reactions, severe reactions like Stevens-Johnson syndrome.

Cephalosporins

Derived from fungus; effective against gram-negative bacteria.
Generations:
- First Generation: Limited CSF penetration.
- Second/Third Generations: Effective against gram-negative pathogens; suitable for complex infections.

Macrolides

Include azithromycin and clarithromycin.
Action: Inhibit protein synthesis in bacteria; lower GI side effects than older macrolides.
Indications: Alternative for patients allergic to penicillin.