introduction to infectious disease.pptx

1. Wafa Mohamed
clinical pharmacist, BCPS2015
Infectious Disease Pharmacist.2020
Introduction to infectious
disease

2. Classification of bacteria

3. Gram positive vs gram negative Bacteria

4. Gram-Positive Bacteria

5. Gram-Negative Bacteria

6. Bacterial infections and common organisms

8. Classification of antibiotics
• Beta-Lactams
o Penicillins
o Cephalosporins
• β- lactamase inhibitors
• Carbapenems
• Monobactams Astreonam
• Glycopeptides vancomycin and tecioplanin
• Lipoglycopeptides(Dalbavancin,
oritavancin,telavancin
• Chloramphenicol
• Quinolones
• Nitrofurans
• Polymyxins
• Fidaxomicin
• Tetracyclines
• Aminoglycosides
• Macrolides
• KetolidesTelithromycin
• Lincosamides
• Streptogramins(quinupristin – dalfopristin
• LipopeptidesDaptomycin,
• Oxazolidinones(Linezolid
• Sulfonamides
• Trimethoprim
• Nitroimidazoles
• Rifamycins
• Fusidic acid
• Mupirocin
• Glycylcycline tiga

9. Anti- pseudomonal activity

10. Staph…examples
mrsa
• In pt
• Vancomycin
• Daptomycin
• Linezolid
• Televancin
• Out pt
• Doxycylin
• TMP/SMZ
• Clindamycin
mssa
• Naficillin
• Oxacilllin
• Dicloxacillin
• Mithicillin
• Co amoxiclav
• Cefazolin/cephalexin
• ………
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12. Efficacy at the Site of Infection
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13. • Efficacy at the Site of Infection:
•For example, first- and second-generation cephalosporins
and macrolides do not cross the blood-brain barrier.
•Fluoroquinolones achieve high concentrations in the
prostate and are preferred oral agents for the treatment of
prostatitis.
• Daptomycin, an excellent bactericidal agent against gram-
positive bacteria, is not useful for treatment of pneumonia
because it is inactivated by lung surfactant.
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14. •Many antibiotics (eg, aminoglycosides) are less active in the
low-oxygen, low-pH, and high-protein environment of
abscesses, and drainage of abscesses to enhance antimicrobial
efficacy is recommended when possible.
•Agents in the same class can differ from one another; for
example, moxifloxacin does not achieve significant urinary
concentrations because of its low renal excretion and is
therefore not suitable for treatment of UTIs
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15. Risk factors forMDROs
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16. Risk Factors
MDR/Health-care associated pathogens Fungemia
• broad spectrum antibiotics within 90 d
• hospitalization >5 d
• local high antibiotic resistance rates
• residence in LTCF
• chronic dialysis within 30 d
• home wound care
• family member with MDR infection
• mechanical ventilation ≥5 d
• immunosuppression
• structural lung disease
• IV drug use
• COPD (Pseudomonas spp.)
• Influenza infection (MRSA)
• broad-spectrum antibiotics
• central venous catheter
• parenteral nutrition
• renal replacement therapy in ICU
• neutropenia
• hematologic malignancy
• implantable prosthetic devices
• immunosuppression
• chemotherapy
Clin Infect Dis 2007;44:S27-72
Am J Respir Crit Care Med 2005;171:388-416
Clin Infect Dis 2009;49:1-45
Clin Infect Dis 2009;48:503-35

17. Use of Antimicrobial Combinations
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18. Use of Antimicrobial Combinations
•combination of 2 or more antimicrobial agents is recommended
when:
•When Agents Exhibit Synergistic Activity Against a Microorganism.
•When Critically Ill Patients Require Empiric Therapy Before
Microbiological Etiology and/or Antimicrobial Susceptibility Can Be
Determined
•To Extend the Antimicrobial Spectrum Beyond That Achieved by Use
of a Single Agent for Treatment of Polymicrobial Infections.
•To Prevent Emergence of Resistance
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19. Susceptibility Testing

20. • the European Committee on Antimicrobial Susceptibility
Testing(EUCAST),
• the Clinical & Laboratory Standards Institute (CLSI).

21. Susceptibility Testing
• For each organism–antibiotic pair, there is a particular cutoff MIC
that defines susceptibility. This particular MIC is called the breakpoint
• Note that just because an antibiotic has the lowest MIC for a pathogen
it does not mean it is the best choice
• different antibiotics achieve different concentrations in the body in
different places. Thus, antibiotic MICs for a single organism generally
should not be compared across different drugs in selecting therapy.

22. • categories of “susceptible,” “susceptible,
dosedependent,”“intermediate,” and “resistant.
• A ‘breakpoint’ is the antibiotic concentration used in
the interpretation

24. • broth dilution methods are generally considered the
gold standard.

25. Static Versus Cidal

26. Static Versus Cidal
•for certain infections bactericidal drugs are preferred.
• Such infections include endocarditis,
meningitis,infections in neutropenic patients, and
possibly osteomyelitis.
• The immune system may not be as effective in fighting
these infections because of the anatomic location or the
immunosuppression of the patient

27. • Bactericidal
• Penicillins
• Cephalosporins
• Carbapenems
• Monobactams
• Vancomycin (slowly)
• Fluoroquinolones
• Aminoglycosides
• Metronidazole
• Daptomycin
•Bacteriostatic
•Macrolides
•Tetracyclines
•Linezolid

28. Pharmacokinetic/Pharmacodynamic
Relationships

29. Pharmacokinetic/Pharmacodynamic Relationships
• for certain antibiotics, activity against microorganisms
correlates with the duration of time that the
concentration of the drug remains above the MIC
(time-dependent activity).
• For other antibiotics, antibacterial activity correlates
not with the time above the MICnbut with the ratio of
the peak concentration of the drug to the MIC
• (concentration-dependent or time-independent
activity).

30. • For some antibiotics,the best predictor of activity is
the ratio of the area under the concentration–time
curve (AUC) to the MIC

31. •The practical implications of these findings are in the design
of antibiotic dosing schedules: aminoglycosides are now
frequently given as a single large dose daily to leverage the
concentration-dependent activity
•some clinicians are administering beta-lactam drugs such as
ceftazidime ascontinuous or prolonged infusions because of
their time-dependent activity.

32. •As target values for these parameters that predict
efficacy are found, there may be an increase in the
individualization of dosing of antibiotics to achieve
these target values.

33. • The end