Application: Antimicrobial Agents
Antimicrobial agents are essential components in the treatment of various bacterial infections as they help to kill or prevent the growth of microbes such as bacteria, fungi, and protozoans. Prior to the discovery of antimicrobial agents, treatment options for patients with bacterial infections were limited. For many patients, treatment often resulted in the amputation of limbs or even death. Today, treatment options for bacterial infections typically have a more positive prognosis. Due to the various types of infections presented in patients, it is essential to be able to identify the underlying cause of the infection “whether bacterial or viral” before recommending drug treatments. This will help you identify whether or not an antimicrobial agent would be appropriate and which specific agent would target the infection. In this Assignment, you consider the appropriate use of antimicrobial agents for infections.
Review this week’s media presentation on principles of antimicrobial therapy, as well as Chapter 8 of the Arcangelo and Peterson text.
Consider the categories of antimicrobial agents.
Think about differences between viral and bacterial infections.
Reflect on why proper identification of the infection is key to selecting the proper antimicrobial agent.
Write a 2- to 3- page paper that addresses the following:
Describe the categories of antimicrobial agents.
Describe differences between viral and bacterial infections.
Explain why proper identification of viral and bacterial infections is key to selecting the proper antimicrobial agent.
Reminder: The School of Nursing requires that all papers submitted include a title page, introduction, summary, and references.
Please use scholarly references including course text( Arcangelo &Peterson(2013)Refers to Principles of Antimicrobial tharapy ( p.96-117)
All references must be 5 years and above.
There are many categories that are used to classify antimicrobial agents. Some of the categories include the site of action, drugs, and antimicrobial agents that define This PDR, XDR, and MDR. There is a very thin line that defines the difference between bacterial and viral infections. This is founded on the fact an infection might begin as viral and end up being bacterial. In such a case, there is a need to consider both viral and bacterial treatments. There should be keen diagnosis so as to identify if an infection is bacterial or viral, which ensures proper treatment. The proper identification of viral and bacterial infections helps the choosing the proper antimicrobial agents.
Antimicrobial agents are synthetic or natural substances that can inhibit the growth of or kill microorganisms. Antimicrobial agents can be classified based on the site of action or drugs’ among others, which results in many categories. They also can be classified as antibacterial, antiviral, or antifungal (Wainwright, 2009). This paper aims at discussing the various antimicrobial agent categories, the major differences between viral and bacterial infections, and why a proper identification of the two infections is significant in choosing appropriate antimicrobial agents.
Categories of antimicrobial agents
There are many categories that can be used for antimicrobial agents.
- Site of action; there are five sites of target or action that are used to classify antimicrobial agents.
- Protein synthesis can be inhibited by Chloramphenicol, Erythromycin, Tetracyclines, Streptomycin, and Amoniglycosides through different mechanisms (Saga & Yamaguchi, 2009).
- Streptomycin and Aminoglycosides bind to 30S subunit irreversibly and hinder the initiation complex formation. This stops protein synthesis.
- In addition, Tetracyclines bind to 30S, which interferes with the attachment of the charged tRNA on the ribosome’s ‘A’ site.
- Chloramphenicol and Erythromycin binds on the 50S irreversibly. As a result, the growing polypeptide chain is not formed (Kingston, 2012).
- Nucleic acid synthesis’ inhibition
- Quinolones restrain DNA gyrase, which hinder the supercoiled DNA from relaxing during replication.
- Rifampicin that hinders bacterial RNA polymerase a’ mRNA synth.
- Cell membrane function; the function of the cell memberane can be inhibited by;
- Eukaryotic fungi’s sterols (ergosterol) (Wainwright, 2009).
- Gram negative bacteria’s phospholipids (Peterson & Arcangelo, 2013).
- Cell wall synthesis’ inhibition; antimicrobial agents that inhibit the synthesis of the cell wall prevents the synthesis of the peptidoglycan through two varying manners (Peterson & Arcangelo, 2013).
- Inhibiting linear strands’ synthesis- Bacitracin and vancomycin)
- Inhibiting the strands’ cross-linking- Beta-lactams such as cephalosporins and penicillins.
- Inhibit the synthesis of folic acid; there are two antimicrobial agents that prevent folic acid synthesis.
- Sulfonamides – sulfa drugs (Levy, 2011).
- Antimicrobial agents can also be categorized based on drugs (Gupta, Hooton & Stamm, 2011).
- Beta-lactams are antibiotics that have a beta-lactam ring.
- Penicillins end with ‘illin.’ Some examples are penicillin, methicillin, amoxicillin, and ampicillin.
- Cephalosporins begin with ‘cef’ or ‘ceph.’ These include cefaclor, cephalexin, and cephalothin among others (Kingston, 2012).
- Aminoglycosides end with a ‘micin’ or ‘mycin’ and include neomycin, amikacin, gentamicin, and streptomycin.
- Tetracyclines end with a ‘cline’. Some of the examples are doxycycline and oxytetracycline (Peterson & Arcangelo, 2013).
- Macrolides- Erythromycin
- Lincosamides- Clindamycin
- Sulfonamides- sulfamethoxazole
- Fluoroquinolones/ Quinolones- ciprofloxacin, norfloxacin, and nalidixic acid.
- Antimicrobial agents can be classified based on Enterobacteriaceae categories. This is used in defining PDR, XDR, and MDR.
- Aminoglycosides includes Netilmicin, Amikacin, Tobramycin, and Gentamicin.
- Carbapenems- Doripenem, Meropenem, Imipenem, and Ertapenem.
- Glycylcyclines- Tigecycline
- Monobactams- Aztreonam (Peterson & Arcangelo, 2013).
- Phenicols- Chloramphenicol
- Phosphonic acids- Fosfomycin
- Polymyxins- Colistin
- Tetracyclines- Minocycline, Doxycycline, and Tetracycline.
Differences between bacterial and viral infections
Bacterial infections are as a result of bacteria and may include urinary tract infections or strep throat. Sometimes, an antibiotic might be used to fight the bacteria while some bacterial infections might go away on their own following the body’s fighting immune system. The single-celled microorganisms thrive in various environments; extremes of heat or cold, or people’s intestines where they digest food (Peterson & Arcangelo, 2013). Although some bacteria are not harmful, bacterial illnesses may become very serious such as bacterial meningitis and sepsis. Kingston (2012) argues that bacterial infections may also be as a result of a secondary infection (pneumonia, ear infection, or sinusitis) or it might have started with a viral infection.
Some of the diseases that result from viral infections include common cold and chicken pox. Some of the common viral infections for example an (URIs) upper respiratory infection can be detected through difficult sleeping, sore throat, low-grade fever, cough, and runny nose. There are no anti-viral medications or antibiotics that can hasten the recovery from cold (Kingston, 2012). Viruses are tiny micro-organisms that need living hosts such as plants, animals, or people so as to be able to multiply. Viral infections are prevented through vaccinations at an early age. There are over-the-counter medications that help in relieving the symptoms (Wainwright, 2009).
Why proper identification of bacterial and viral infections is key to selection of proper antimicrobial agents
It is extremely important for a doctor to make the proper identification of bacterial or viral infections so as to be able to select proper antimicrobial agents (Peterson & Arcangelo, 2013). Bacterial infections can be diagnosed through urine or throat cultures and lab tests. Sometimes, professionals are unable to determine if an illness is as a result of viral or bacterial infection. A person might be suffering from a viral infection but using antibiotic drugs will only kill the bacteria. Some diseases such as diarrhea, meningitis, or pneumonia may be caused by either bacteria or virus. According to Peterson and Arcangelo (2013), using antibiotics inappropriately results to bacterial disease strains that are resistant to treatment through the use of various antibiotic medications. Therefore, proper antimicrobial agents can be selected following a proper identification.
Viral or bacterial infection can be exogenous or endogenous. On the same note, the symptoms and signs differ depending on the severity and site on infection. The fact that there is a viral or bacterial infection implies that the microorganism and host have interacted. This interaction is influenced by microbial virulence factors and host immune status (Levy, 2011). On the same note, there are numerous factors that should be considered before settling on a particular antimicrobial agent (Kingston, 2012). A proper diagnosis should entail composite information such as physical examination, history, laboratory data, and radiographic findings.
From the foregoing discussion, it has been identified that there are many categories of antimicrobial agents. The categorization is based on many factors. When treating bacterial and viral infections, a professional has to be keen to ensure that the proper agent identification is made so as to ensure proper antimicrobial agents. While many bacterial infections can go away following action of the body’s immune system, viral infections are prevented through immunizations at childhood.
Gupta, K., Hooton, T. M., & Stamm, W. E. (2011). Increasing antimicrobial resistance and the management of uncomplicated community-acquired urinary tract infections. Annals of internal medicine, 135(1), 41-50.
Kingston, W. (2012). Irish contributions to the origins of antibiotics. Irish journal of medical science 177 (2): 87–92.
Levy, S. B. (2011). Drug Resistance: The New Apocalypse (special issue) Trends Microbiol 2: 341–425.
Peterson, A. M., & Arcangelo, V. P. (2013). Pharmacotherapeutics for advanced practice: a practical approach. Philadelphia : Wolters Kluwer/Lippincott Williams & Wilkins.
Saga, T., & Yamaguchi, K. (2009). History of Antimicrobial Agents and Resistant Bacteria. JMAJ 52(2), 103- 108.
Wainwright, M. (2009). Moulds in ancient and more recent medicine. Mycologist 3 (1): 21–23.