BETHLEHEM UNIVERSITYSecond Neonatal Gathering Fall 2007

Antibiotic misuse

Presented by: Kawkab G.Sa’ed

Supervised by:Dr. Hania Al-Jouzy

Antibiotic Misuseand its role in emergence of multi drug resistant micro-organisms

Out line

1. Introduction.2. Definitions.3. Resistance.4. Basic principles of antimicrobial

use.5. Monitoring bacterial resistance

and antibiotic usage.6. Combination antimicrobial

therapy.7. Conclusion.

Introduction

In the past the production of antimicrobials gave us an advantage in our struggle against micro-organisms.

Now the increase of antimicrobial resistance is now decreasing our ability to control the spread of infectious diseases.

Introduction

The misuse of antimicrobial agents has been observed in many countries around the world, resulting in the development of multiple resistant pathogens and the emergence of multidrug-resistant bacterial m.o.

“super-bugs.”

Introduction

The occurrence of super-bugs is associated with :

-treatment failure, higher morbidity and mortality;

-An increased length of hospital stay.

-Increased cost of healthcare.-And constitutes a major risk for

human health

Introduction

As the literature shows Antimicrobial resistance is multifactorial :

• In all known cases, the introduction of new In all known cases, the introduction of new antimicrobial compounds resulted in the antimicrobial compounds resulted in the emergence of resistanceemergence of resistance.

Misuse of antibiotic by the physicians:– Administering antibiotics for viral

infections– Prescribing wrong antibiotics

The link between antimicrobial consumption and the emergence of bacterial resistance is now clearly established in hospital settings.

Definitions

Antimicrobial medications: medications that inhibit the growth of or kill microorganisms such as bacteria, fungi, viruses, protozoa.

Resistance: the ability of microorganisms to counteract the bacteriostatic or bactericidal effects of an antimicrobial agent.

Resistance How do m.o.develop resistance ?

m.o. develop resistance by:

1.Enzymes: m.o produce various enzymes to inactive antimicrobial agents .

e.g. B-lactamase inactive penicillins and cephalosporines.

2.Decreased cellular penetration: m.o. alter their cell wall permeability to prevent penetration of antimicrobial agents into the cell.

e.g. pseudomonas- ceftazidime .

How do m.o.develop resistance?

3.Altered target proteins: m.o. change target proteins so that antimicrobial agents cannot bind and elicit antimicrobial activity,(e.g streptococcus pneumonia resistance to penicillin).

4.Efflux pump: m.o. pump antimicrobial agents out of the cell before the antimicrobial agent can kill the m.o. (e.g. S.pneumonia resistance to erythromycin).

Basic principles of antimicrobial use

1.Antibiotics must reach the target tissue in a concentration adequate to inhibit the growth of or to kill the desired m.o.

2.The choice of antimicrobial agents must take into account:

a. m.o. susceptibility to available antimicrobial agents.

b. relative permeability of the target tissue to agent of choice (e.g. blood

brain barrier) .

c. Bioactivity of chosen antimicrobial agent in target tissue

(bactericidal or bacteriostatic) .

d. Specific characteristics of the individual patient in relation to the chosen antimicrobial's toxicities (e.g. the blood levels of a nephrotoxic antimicrobial such as gentamicin should be closely monitored in patients with impaired renal function).

Monitoring bacterial resistance and antibiotic usage.

A good program for the prevention of resistance must include an active system for the surveillance of antimicrobial resistance and antibiotic usage.

No specific action can be developed if antimicrobial resistance and antibiotic consumption are not monitored properly.

Monitoring bacterial resistance and antibiotic usage

Microbiology laboratories must

provide antimicrobial susceptibility data to

guide clinicians’ choices in antibiotic treatment and to aid in the prudent use

of antibiotics.

The reporting of antimicrobial resistance

data is necessary to determine the optimal

empirical antimicrobial therapy according

to local resistance patterns, and to fight against the emergence of antimicrobial resistance.

Combination antimicrobial therapy According to literature, It has been reported previously, that the emergence

of resistance is less common when combination therapy is used.

Recently No significant advantage was found with combination therapy regarding the development of antimicrobial resistance, but this is

controversary,as in some particular situations CAT may be warranted

(e.g. treatment of pseudomonas aeruginosa and enterobacter aerogenes infections.

The emergence of resistance during single-drug therapy has been documented, especially with third-generation cephalosporin for the treatment of enterobacter infection.

conclusionMany aspects of interventions seem to lead to

the best results in the fight against antimicrobial resistance.

Actions should be determined and prioritized.

The development of an effective system for the surveillance of antimicrobial use and anti microbial resistance is mandatory.

Appropriate infection control measures should also be reinforced to control the cross-transmission of resistant microorganisms.

Educational programmes and practice guidelines have a positive impact in terms of the appropriateness of antimicrobial treatment.

Continuous efforts are needed to maintain educational programmes, hygiene, antibiotic policies and surveillance system to control antimicrobial resistance.

References Deacon, J.and O,Neill,P.(1999)Core Curriculum for Neonatal Intensive Care

Nursing,(3rd ed.),PHiladelphia, W.B. Saunders.

Foucault C,Brouqui O.2007, How to fight antimicrobial resistance. (assessed 15.1.2008) http//www.pubmed.gov

Web site: Am J Crit Care.2007 march;16(2):110-120. (assessed 15.1.2008)