Antibiotic Resistance

Table of Contents

Introduction3

Discussion & Analysis4

Mechanism of Resistance4

Genetically Mediated Antibiotic Resistance5

Nongenetic Modes of Resistance7

Prevention of Resistance8

Conclusion9

References10

Antibiotic Resistance

Introduction

With the discovery of penicillin by Alexander Fleming in 1928, the development of antibiotics revolutionized the treatment of infectious diseases. Antibiotics are a type of antimicrobial agent, a general term for substances such as drugs or chemicals that kill or slow the growth of bacteria or other microbes (organisms so small they can only be seen under a microscope) such as viruses, fungi, and parasites. The term antibiotics technically refers only to antimicrobial agents made from molds or bacteria, such as penicillin and streptomycin, although this distinction is not always observed in everyday language. The development of effective antibiotics is one of the great success stories of modern medicine: before the widespread use of antibiotics, infectious diseases were a common cause of death, while today such deaths are a relative rarity in developed nations (with the exception of acquired immune deficiency syndrome [AIDS], for which no cure has been discovered). Noncontagious chronic diseases such as cancer, stroke, and cardiovascular disease have largely replaced infectious diseases as the major threats to life. A similar trend exists in many developing countries, where chronic diseases are fast displacing infectious diseases as the leading causes of death.

However, with the increasing and unjustified use of these molecules, bacteria have learned to defend themselves and to adapt and become resistant to certain antibiotics. Despite the development of new classes of anti-infectives, in an attempt to cope with this phenomenon, bacterial resistance has increased, making antibiotics ineffective on some of them. In recent years, health authorities have become aware of the seriousness of the situation and put in place in 2001, a national plan to preserve the effectiveness of antibiotics.

Discussion & Analysis

The rapid increase in the amount of resistance is a problem in healthcare today. In the past, methicillin-resistant Staphylococcus aureus (MRSA) infections were only seen in hospitals or other institutional settings; however, patients now acquire infections in the community. This is cause for concern, because most MRSA infections cannot be treated with standard antibiotics and require treatment with a broad-spectrum antibiotic. There has also been a steady climb in the number of nosocomial (acquired in the hospital) multidrug-resistant infections. Some of these are more difficult to treat than MRSA infections and can have serious adverse effects on already ill patients. These changes have begun to limit the treatments available in both nosocomial and community-acquired infections. Other factors leading to antibiotic resistance include the widespread use of consumer products such as antibacterial cutting boards, tissues, and other products containing antibiotics.

Mechanism of Resistance

There are multiple genetic, idiopathic (unknown), and iatrogenic (caused by a physician) factors contributing to the crisis of antibiotic resistance.

There are four main mechanisms by which bacteria acquire resistance:

Enzymatic degradation of the drug (the bacteria break down the drug)

Modification of the drug's target

Decreased permeability (bacteria change borders to block antibiotics from entering)

Active export of the drug (bacteria pump antibiotics out of cells)

Bacterial and human cells differ in a few ...