4 - Approach to the Patient With Infection

Question 1

List 2 treatment objectives for patients with an infectious disease.

Answer 1

Cure Infection

Prevent & Minimize Complications
Infxn Related Examples:
UTI –> Kidney Failure
Meningitis –> Neuro Dmg

Treatment Related:
Drug Toxicity
Selection of pathogenic or resistant organisms

Question 2

State the primary goal of antimicrobial stewardship.

Answer 2

• *Optimize clinical outcomes** while
• minimizing unintended consequences* of AB use like:

resistance / toxcity / selection of pathogenic organisms

Question 3

Discuss the meaning of the 5-D’s of Antimicrobial Stewardship

Answer 3

Choosing the RIGHT:
Diagnosis

Drug

Dose

De-escalation

Duration

Question 4

Discuss the meaning of the 5-D’s of Antimicrobial Stewardship

DIAGNOSIS

Answer 4

Presumptive Diagnosis:

Subjective = Patient Complaints

Objective = Physical exam + labs

Question 5

Discuss the meaning of the 5-D’s of Antimicrobial Stewardship

DRUG

Answer 5

Empiric AB Choice:
best GUESS of the MOST LIKELY PATHOGEN
Lower MORTALITY with adequate initial (empiric best guess) regimen

Site of Infection
likely pathogens

Pertinent PMH
increase risk for specific pathogens

Question 6

Discuss the meaning of the 5-D’s of Antimicrobial Stewardship

Answer 6

Choosing the RIGHT:
Diagnosis

Drug

Dose

De-escalation

Duration

Question 7

Discuss the meaning of the 5-D’s of Antimicrobial Stewardship

Answer 7

Choosing the RIGHT:
Diagnosis

Drug

Dose

De-escalation

Duration

Question 8

Discuss the meaning of the 5-D’s of Antimicrobial Stewardship

Answer 8

Choosing the RIGHT:
Diagnosis

Drug

Dose

De-escalation

Duration

Question 9

List 3 risk factors for infection with
antimicrobial resistant pathogens.

Answer 9

recent HOSPITALIZATION

NURSING HOME resident

recent ANTIBIOTIC USE

Question 10

Discuss why knowledge of the patient’s medication list helps in the selection of appropriate antibiotic regimens.

Answer 10

Previous Antibiotics used

Drug Interactions

Avoid OVER-LAPPING TOXICITIES

Side Effects

Question 11

1. Discuss why knowledge of the patient’s serum creatinine and liver function tests helps in the selection of an appropriate antibiotic regimen.

Answer 11

Reduce Dose

Dose Adjustments

Creatinine Clearance

Question 12

Explain the rationale for calculating a patient’s creatinine clearance.

Answer 12

Determines rate of the drug cleared from the body

DOSAGE REDUCTION

Question 13

Cockroft Gault Equation

Answer 13

140-age x IBW (0.85 if female)
(serum creatinine x 72)

Question 14

1. Explain what is meant by the term
   * *“empiric antibiotic therapy.”**

Answer 14

EDUCATED GUESS
of the
most likely pathogen

to make a PRESUMPTIVE DIAGNOSIS

Lower mortality with an adequate INITIAL (empiric) regimen

Question 15

1. Describe how you would use an antibiogram to help in the selection of appropriate empiric antibiotic regimens.

Answer 15

To determine the
SUSCEPTIBILITY OF AN ORGANISM
to a
SPECIFIC ANTIBIOTIC

Helps select an:
EMPIRIC AB white awaiting culture results

Question 16

1. Discuss one limitation of using an antibiogram to help in the selection of appropriate empiric antibiotic regimens.

Answer 16

Susceptibility between intitutions may VARY

Institution specific antibiograms preferred

Question 17

1. Discuss the situations in which you would select the intravenous (IV) route, or the oral route to administer antibiotics.

Answer 17

IV = Hospitilized / Severe Infxn

IM = avoid with HTN due to reduced absorption

Oral = need adequate GI absorption

Question 18

1. Discuss how you would
   * *evaluate a patient’s response to therapy.**

Answer 18

↓Patient Complaints

Normalization of Lab tests
↓WBC & ↓Temp

• is it causing HARM?*
• New complaints / Worsening Lab test*s

Question 19

1. Discuss how you would use culture and susceptibility data.

Answer 19

See what Bacteria is SUSCEPTIBLE to each Antibiotic

DE-ESCALATION
Change to NARROW-SPECTRUM AB to:
minimize resistant bacteria
Toxicity and Costs

Question 20

Know that selection of an optimal antibiotic regimen requires the selection of the
appropriate antibiotic, dose, route, frequency of administration, and duration of therapy

Question 21

List 5 manifestations of an
unsatisfactory response to antibiotic therapy.

Answer 21

Unsatisfactory improvement of “Patient Complaints”

Persistant Fever

Unsatisfactory Normalization of Tests

Persistantly positive CULTURES
Esp from sterile body sites

Onset of new “Patient Complaints** or **Lab Tests

Question 22

List 7 possible reasons for an
unsatisfactory response to antibiotic therapy

Answer 22

Suboptimal AB choice
resistant bacteria –> check Cultures

Suboptimal Regimen
Dose / Route / Frequency / Duration

Actually Recieving AB?

Toxicity

Surgical Intervention?

Incorrect Diagnosis

Disreprency in in-vitro susceptibility & outcome
drug does not reach adequate levels @ site of infxn = CNS
BacteriCIDAL AB’s required for selected infxn = endocarditis

Question 23

Describe the presentation of patients with drug fever.

Beta-Lactams / Sulfonamides

AmphoTERicin B + others

Answer 23

• *7-10 days** after exposure to drug
• sooner if PRIOR EXPOSURE*

Resolves within 48hrs of drug DC

• *PATIENTS GENERALLY FEEL WELL**
• do NOT notice the fever*

Question 24

1. Discuss the reason why not all positive cultures requires treatment with antibiotics to eliminate the identified organisms.

Answer 24

NORMAL BACTERIAL FLORA
are protective

CONTAMINATED SPECIMEN
por technique , etc

Question 25

Dose Selection for Renally Eliminated Drugs:

Renal Insufficiency

Elderly

Answer 25

Lower CrCl –> slower elimination

Lower Daily Dose

Question 26

Dose Selection for Renally Eliminated Drugs:

Trauma / Burn

Pregnancy

Children

Answer 26

HIGHER CrCl –> FASTER ELIMINATION

HIGHER DAILY DOSE

Question 27

Criteria to:
SWITCH from IV –> ORAL AB

De-Escalation

Answer 27

Criteria for Oral AB:
Patient Improvement

Afebrile for 24-48 Hours

↓WBC count

Functioning GI tract

Drugs with good oral Bioavailability:
Fluoroquinolones, metronidazole, linezolid, Trimethoprim/sulfamethoxazole, fluconazole, others