Antimicrobial spectrum

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A simplified diagram showing common disease-causing bacteria and the antibiotics which act against them. 2023-12-12 Antibiotics Coverage Diagram.jpg
A simplified diagram showing common disease-causing bacteria and the antibiotics which act against them.

The antimicrobial spectrum of an antibiotic means the range of microorganisms it can kill or inhibit. Antibiotics can be divided into broad-spectrum antibiotics, extended-spectrum antibiotics and narrow-spectrum antibiotics based on their spectrum of activity. Detailedly, broad-spectrum antibiotics can kill or inhibit a wide range of microorganisms; extended-spectrum antibiotic can kill or inhibit Gram positive bacteria and some Gram negative bacteria; narrow-spectrum antibiotic can only kill or inhibit limited species of bacteria. [1] [2] [3]

Contents

Currently no antibiotic's spectrum can completely cover all types of microorganisms. [4]

Determination

The antimicrobial spectrum of an antibiotic can be determined by testing its antimicrobial activity against a wide range of microbes in vitro . Nonetheless, the range of microorganisms which an antibiotic can kill or inhibit in vivo may not always be the same as the antimicrobial spectrum based on data collected in vitro. [2] [5]

Significance

Narrow-spectrum antibiotics have low propensity to induce bacterial resistance and are less likely to disrupt the microbiome (normal microflora). [3] On the other hand, indiscriminate use of broad-spectrum antibiotics may not only induce the development of bacterial resistance and promote the emergency of multidrug-resistant organisms, but also cause off-target effects due to dysbiosis. [3] [6] They may also have side effects, such as diarrhea or rash. [7] Generally, a broad antibiotic has more clinical indications, and therefore are more widely used. [2] [8] The Healthcare Infection Control Practices Advisory Committee (HICPAC) recommends the use of narrow-spectrum antibiotics whenever possible. [9]

Examples

See also

Related Research Articles

<span class="mw-page-title-main">Antibiotic</span> Antimicrobial substance active against bacteria

An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and prevention of such infections. They may either kill or inhibit the growth of bacteria. A limited number of antibiotics also possess antiprotozoal activity. Antibiotics are not effective against viruses such as the ones which cause the common cold or influenza; drugs which inhibit growth of viruses are termed antiviral drugs or antivirals rather than antibiotics. They are also not effective against fungi; drugs which inhibit growth of fungi are called antifungal drugs.

<span class="mw-page-title-main">Ampicillin</span> Antibiotic

Ampicillin is an antibiotic belonging to the aminopenicillin class of the penicillin family. The drug is used to prevent and treat a number of bacterial infections, such as respiratory tract infections, urinary tract infections, meningitis, salmonellosis, and endocarditis. It may also be used to prevent group B streptococcal infection in newborns. It is used by mouth, by injection into a muscle, or intravenously.

<span class="mw-page-title-main">Antimicrobial resistance</span> Resistance of microbes to drugs directed against them

Antimicrobial resistance (AMR) occurs when microbes evolve mechanisms that protect them from the effects of antimicrobials. All classes of microbes can evolve resistance where the drugs are no longer effective. Fungi evolve antifungal resistance, viruses evolve antiviral resistance, protozoa evolve antiprotozoal resistance, and bacteria evolve antibiotic resistance. Together all of these come under the umbrella of antimicrobial resistance. Microbes resistant to multiple antimicrobials are called multidrug resistant (MDR) and are sometimes referred to as superbugs. Although antimicrobial resistance is a naturally occurring process, it is often the result of improper usage of the drugs and management of the infections.

<span class="mw-page-title-main">Broad-spectrum antibiotic</span> Treatment for a wide range of bacteria

A broad-spectrum antibiotic is an antibiotic that acts on the two major bacterial groups, Gram-positive and Gram-negative, or any antibiotic that acts against a wide range of disease-causing bacteria. These medications are used when a bacterial infection is suspected but the group of bacteria is unknown or when infection with multiple groups of bacteria is suspected. This is in contrast to a narrow-spectrum antibiotic, which is effective against only a specific group of bacteria. Although powerful, broad-spectrum antibiotics pose specific risks, particularly the disruption of native, normal bacteria and the development of antimicrobial resistance. An example of a commonly used broad-spectrum antibiotic is ampicillin.

<span class="mw-page-title-main">Oxytetracycline</span> Antibiotic

Oxytetracycline is a broad-spectrum tetracycline antibiotic, the second of the group to be discovered.

<span class="mw-page-title-main">Doxycycline</span> Tetracycline-class antibiotic

Doxycycline is a broad-spectrum antibiotic of the tetracycline class used in the treatment of infections caused by bacteria and certain parasites. It is used to treat bacterial pneumonia, acne, chlamydia infections, Lyme disease, cholera, typhus, and syphilis. It is also used to prevent malaria. Doxycycline may be taken by mouth or by injection into a vein.

An antimicrobial is an agent that kills microorganisms (microbicide) or stops their growth. Antimicrobial medicines can be grouped according to the microorganisms they act primarily against. For example, antibiotics are used against bacteria, and antifungals are used against fungi. They can also be classified according to their function. The use of antimicrobial medicines to treat infection is known as antimicrobial chemotherapy, while the use of antimicrobial medicines to prevent infection is known as antimicrobial prophylaxis.

A narrow-spectrum antibiotic is an antibiotic that is only able to kill or inhibit limited species of bacteria. Examples of narrow-spectrum antibiotics include fidaxomicin and sarecycline.

Multiple drug resistance (MDR), multidrug resistance or multiresistance is antimicrobial resistance shown by a species of microorganism to at least one antimicrobial drug in three or more antimicrobial categories. Antimicrobial categories are classifications of antimicrobial agents based on their mode of action and specific to target organisms. The MDR types most threatening to public health are MDR bacteria that resist multiple antibiotics; other types include MDR viruses, parasites.

<span class="mw-page-title-main">Tigecycline</span> Chemical compound

Tigecycline, sold under the brand name Tygacil, is a tetracycline antibiotic medication for a number of bacterial infections. It is a glycylcycline class drug that is administered intravenously. It was developed in response to the growing rate of antibiotic resistant bacteria such as Staphylococcus aureus, Acinetobacter baumannii, and E. coli. As a tetracycline derivative antibiotic, its structural modifications has expanded its therapeutic activity to include Gram-positive and Gram-negative organisms, including those of multi-drug resistance.

Production of antibiotics is a naturally occurring event, that thanks to advances in science can now be replicated and improved upon in laboratory settings. Due to the discovery of penicillin by Alexander Fleming, and the efforts of Florey and Chain in 1938, large-scale, pharmaceutical production of antibiotics has been made possible. As with the initial discovery of penicillin, most antibiotics have been discovered as a result of happenstance. Antibiotic production can be grouped into three methods: natural fermentation, semi-synthetic, and synthetic. As more and more bacteria continue to develop resistance to currently produced antibiotics, research and development of new antibiotics continues to be important. In addition to research and development into the production of new antibiotics, repackaging delivery systems is important to improving efficacy of the antibiotics that are currently produced. Improvements to this field have seen the ability to add antibiotics directly into implanted devices, aerosolization of antibiotics for direct delivery, and combination of antibiotics with non antibiotics to improve outcomes. The increase of antibiotic resistant strains of pathogenic bacteria has led to an increased urgency for the funding of research and development of antibiotics and a desire for production of new and better acting antibiotics.

<span class="mw-page-title-main">Dicloxacillin</span> Chemical compound

Dicloxacillin is a narrow-spectrum β-lactam antibiotic of the penicillin class. It is used to treat infections caused by susceptible (non-resistant) Gram-positive bacteria. It is active against beta-lactamase-producing organisms such as Staphylococcus aureus, which would otherwise be resistant to most penicillins. Dicloxacillin is available under a variety of trade names including Diclocil (BMS).

<span class="mw-page-title-main">Tetracycline antibiotics</span> Type of broad-spectrum antibiotic

Tetracyclines are a group of broad-spectrum antibiotic compounds that have a common basic structure and are either isolated directly from several species of Streptomyces bacteria or produced semi-synthetically from those isolated compounds. Tetracycline molecules comprise a linear fused tetracyclic nucleus to which a variety of functional groups are attached. Tetracyclines are named after their four ("tetra-") hydrocarbon rings ("-cycl-") derivation ("-ine"). They are defined as a subclass of polyketides, having an octahydrotetracene-2-carboxamide skeleton and are known as derivatives of polycyclic naphthacene carboxamide. While all tetracyclines have a common structure, they differ from each other by the presence of chloro, methyl, and hydroxyl groups. These modifications do not change their broad antibacterial activity, but do affect pharmacological properties such as half-life and binding to proteins in serum.

<span class="mw-page-title-main">Monobactam</span> Monocyclic β-lactam antibiotics

Monobactams are bacterially-produced monocyclic β-lactam antibiotics. The β-lactam ring is not fused to another ring, in contrast to most other β-lactams.

<i>Acinetobacter baumannii</i> Species of bacterium

Acinetobacter baumannii is a typically short, almost round, rod-shaped (coccobacillus) Gram-negative bacterium. It is named after the bacteriologist Paul Baumann. It can be an opportunistic pathogen in humans, affecting people with compromised immune systems, and is becoming increasingly important as a hospital-derived (nosocomial) infection. While other species of the genus Acinetobacter are often found in soil samples, it is almost exclusively isolated from hospital environments. Although occasionally it has been found in environmental soil and water samples, its natural habitat is still not known.

<span class="mw-page-title-main">Antibiotic misuse</span>

Antibiotic misuse, sometimes called antibiotic abuse or antibiotic overuse, refers to the misuse or overuse of antibiotics, with potentially serious effects on health. It is a contributing factor to the development of antibiotic resistance, including the creation of multidrug-resistant bacteria, informally called "super bugs": relatively harmless bacteria can develop resistance to multiple antibiotics and cause life-threatening infections.

<span class="mw-page-title-main">Omadacycline</span> Chemical compound

Omadacycline, sold under the brand name Nuzyra, is a broad spectrum antibiotic medication belonging to the aminomethylcycline subclass of tetracycline antibiotics. In the United States, it was approved in October 2018, for the treatment of community-acquired bacterial pneumonia and acute skin and skin structure infections.

<span class="mw-page-title-main">Ceftolozane/tazobactam</span> Antibiotic

Ceftolozane/tazobactam, sold under the brand name Zerbaxa, is a fixed-dose combination antibiotic medication used for the treatment of complicated urinary tract infections and complicated intra-abdominal infections in adults. Ceftolozane is a cephalosporin antibiotic, developed for the treatment of infections with gram-negative bacteria that are resistant to conventional antibiotics. It was studied for urinary tract infections, intra-abdominal infections and ventilator-associated bacterial pneumonia.

There are many circumstances during dental treatment where antibiotics are prescribed by dentists to prevent further infection. The most common antibiotic prescribed by dental practitioners is penicillin in the form of amoxicillin, however many patients are hypersensitive to this particular antibiotic. Therefore, in the cases of allergies, erythromycin is used instead.

References

  1. 1 2 3 4 Michelle A. Clark; et al. (2009). Pharmacology (5th ed.). USA: Lippincott Williams & Wilkins. pp.  375–376. ISBN   978-1-4511-4320-1.
  2. 1 2 3 David Warrell; Timothy M. Cox; John Firth; Estée Török (11 October 2012). Oxford Textbook of Medicine: Infection. OUP Oxford. p. 39. ISBN   978-0-19-965213-6.
  3. 1 2 3 Melander, Roberta J.; Zurawski, Daniel V.; Melander, Christian (2018). "Narrow-Spectrum Antibacterial Agents". MedChemComm. 9 (1): 12–21. doi:10.1039/C7MD00528H. ISSN   2040-2503. PMC   5839511 . PMID   29527285.
  4. Erich Lück; Martin Jager (1997). Antimicrobial Food Additives: Characteristics, Uses, Effects. Springer Science & Business Media. p. 39. ISBN   978-3-540-61138-7.
  5. Wiley W. Souba; Douglas W. Wilmore (23 February 2001). Surgical Research. Elsevier. p. 909. ISBN   978-0-08-054214-0.
  6. Francino, M. P. (2015). "Antibiotics and the Human Gut Microbiome: Dysbioses and Accumulation of Resistances". Frontiers in Microbiology. 6: 1543. doi: 10.3389/fmicb.2015.01543 . ISSN   1664-302X. PMC   4709861 . PMID   26793178.
  7. "Comparing Broad- and Narrow-Spectrum Antibiotics for Children with Ear, Sinus, and Throat Infections". www.pcori.org. 2014-10-08. Retrieved 2020-09-05.
  8. Andrew Hitchings; Dagan Lonsdale; Daniel Burrage; Emma Baker (30 March 2014). The Top 100 Drugs e-book: Clinical Pharmacology and Practical Prescribing. Elsevier Health Sciences. p. 94. ISBN   978-0-7020-5515-7.
  9. "Antibiotic Stewardship Statement | HICPAC | CDC". www.cdc.gov. 2019-04-15. Archived from the original on 2019-07-17. Retrieved 2020-09-05.
  10. Zhanel, George; Critchley, Ian; Lin, Lynn-Yao; Alvandi, Nancy (January 2019). "Microbiological Profile of Sarecycline, a Novel Targeted Spectrum Tetracycline for the Treatment of Acne Vulgaris". Antimicrobial Agents and Chemotherapy. 63 (1). doi:10.1128/AAC.01297-18. ISSN   1098-6596. PMC   6325184 . PMID   30397052.