Directed therapy

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Directed therapy refers to the treatment of infections based on specific knowledge of what the causal agent is able to be treated with. It is the opposite to empiric therapy, which refers to the treatment of infections based on the clinical suspicion about what the agent should be able to be treated with, based on experience or guidelines. [1]

Information that directs therapy may medical tests that isolate the cause of an infection, such as microbiological culture, or polymerase chain reaction testing, as well as testing for antimicrobial sensitivities. [1] Often, directed therapy occurs after initial empiric therapy. [2] Empiric therapy is often commenced first, particularly important when antimicrobial sensitivities are not known, or when a severe infection such as one causing sepsis has been identified. [3] In this circumstance, the decision may be made for empiric therapy first. [3] A change to directed therapy may be associated with a change in antimicrobials, a change in the duration of treatment, or the cessation of unnecessary antimicrobials. [2]

Directed therapy is considered important because it ensures a person is completely treated for an infection, and because it can help lower the rate of antimicrobial resistance. [1]

Related Research Articles

Antibiotic 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 common cold or influenza; drugs which inhibit viruses are termed antiviral drugs or antivirals rather than antibiotics.

Antimicrobial resistance Ability of a microbe to resist the effects of medication

Antimicrobial resistance (AMR) occurs when microbes evolve mechanisms that protect them from the effects of antimicrobials. The term antibiotic resistance is a subset of AMR, as it applies to bacteria that become resistant to antibiotics. Resistant microbes are more difficult to treat, requiring higher doses, or alternative medications which may prove more toxic. These approaches may also be more expensive. Microbes resistant to multiple antimicrobials are called multidrug resistant (MDR).

Ciprofloxacin Antibiotic

Ciprofloxacin is an antibiotic used to treat a number of bacterial infections. This includes bone and joint infections, intra abdominal infections, certain type of infectious diarrhea, respiratory tract infections, skin infections, typhoid fever, and urinary tract infections, among others. For some infections it is used in addition to other antibiotics. It can be taken by mouth, as eye drops, as ear drops, or intravenously.

Bloodstream infections (BSIs), which include bacteremias when the infections are bacterial and fungemias when the infections are fungal, are infections present in the blood. Blood is normally a sterile environment, so the detection of microbes in the blood is always abnormal. A bloodstream infection is different from sepsis, which is the host response to bacteria.

Broad-spectrum antibiotic

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.

<i>Klebsiella pneumoniae</i> Species of bacterium

Klebsiella pneumoniae is a Gram-negative, non-motile, encapsulated, lactose-fermenting, facultative anaerobic, rod-shaped bacterium. It appears as a mucoid lactose fermenter on MacConkey agar.

Fusidic acid Antibiotic

Fusidic acid is an antibiotic that is often used topically in creams and eyedrops but may also be given systemically as tablets or injections. The global problem of advancing antimicrobial resistance has led to a renewed interest in its use recently.

Blood culture Test to detect bloodstream infections

A blood culture is a medical laboratory test used to detect bacteria or fungi in a person's blood. Under normal conditions, the blood does not contain microorganisms: their presence can indicate a bloodstream infection such as bacteremia or fungemia, which in severe cases may result in sepsis. By culturing the blood, microbes can be identified and tested for resistance to antimicrobial drugs, which allows clinicians to provide an effective treatment.

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.

Piperacillin Chemical compound

Piperacillin is a broad-spectrum β-lactam antibiotic of the ureidopenicillin class. The chemical structure of piperacillin and other ureidopenicillins incorporates a polar side chain that enhances penetration into Gram-negative bacteria and reduces susceptibility to cleavage by Gram-negative beta lactamase enzymes. These properties confer activity against the important hospital pathogen Pseudomonas aeruginosa. Thus piperacillin is sometimes referred to as an "anti-pseudomonal penicillin".

Tigecycline

Tigecycline, sold under the brand name Tygacil, is an tetracycline antibiotic medication for a number of bacterial infections. It is a glycylcycline 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.

Carbapenem

Carbapenems are a class of highly effective antibiotic agents commonly used for the treatment of severe or high-risk bacterial infections. This class of antibiotics is usually reserved for known or suspected multidrug-resistant (MDR) bacterial infections. Similar to penicillins and cephalosporins, carbapenems are members of the beta lactam class of antibiotics, which kill bacteria by binding to penicillin-binding proteins, thus inhibiting bacterial cell wall synthesis. However, these agents individually exhibit a broader spectrum of activity compared to most cephalosporins and penicillins. Furthermore, carbapenems are typically unaffected by emerging antibiotic resistance, even to other beta-lactams.

Antibiotic sensitivity testing Microbiology test used in medicine

Antibiotic sensitivity testing or antibiotic susceptibility testing is the measurement of the susceptibility of bacteria to antibiotics. It is used because bacteria may have resistance to some antibiotics. Sensitivity testing results can allow a clinician to change the choice of antibiotics from empiric therapy, which is when an antibiotic is selected based on clinical suspicion about the site of an infection and common causative bacteria, to directed therapy, in which the choice of antibiotic is based on knowledge of the organism and its sensitivities.

Empiric therapy or empirical therapy is medical treatment or therapy based on experience and, more specifically, therapy begun on the basis of a clinical "educated guess" in the absence of complete or perfect information. Thus it is applied before the confirmation of a definitive medical diagnosis or without complete understanding of an etiology, whether the biological mechanism of pathogenesis or the therapeutic mechanism of action. The name shares the same stem with empirical evidence, involving an idea of practical experience.

A drug of last resort (DoLR) is a pharmaceutical drug which is tried after all other drug options have failed to produce an adequate response in the patient. Drug resistance, such as antimicrobial resistance or antineoplastic resistance, may make the first-line drug ineffective, especially with multidrug-resistant pathogens or tumors. Such an alternative may be outside of extant regulatory requirements or medical best practices, in which case it may be viewed as salvage therapy.

Medical microbiology Branch of medical science concerned with the prevention, diagnosis and treatment of infectious diseases

Medical microbiology, the large subset of microbiology that is applied to medicine, is a branch of medical science concerned with the prevention, diagnosis and treatment of infectious diseases. In addition, this field of science studies various clinical applications of microbes for the improvement of health. There are four kinds of microorganisms that cause infectious disease: bacteria, fungi, parasites and viruses, and one type of infectious protein called prion.

Cefoxitin

Cefoxitin is a second-generation cephamycin antibiotic developed by Merck & Co., Inc. from Cephamycin C in the year following its discovery, 1972. It was synthesized in order to create an antibiotic with a broader spectrum. It is often grouped with the second-generation cephalosporins. Cefoxitin requires a prescription and as of 2010 is sold under the brand name Mefoxin by Bioniche Pharma, LLC. The generic version of cefoxitin is known as cefoxitin sodium.

Antibiotic misuse

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.

Infections caused by exposure to ionizing radiation can be extremely dangerous, and are of public and government concern. Numerous studies have demonstrated that the susceptibility of organisms to systemic infection increased following exposure to ionizing radiation. The risk of systemic infection is higher when the organism has a combined injury, such as a conventional blast, thermal burn, or radiation burn. There is a direct quantitative relationship between the magnitude of the neutropenia that develops after exposure to radiation and the increased risk of developing infection. Because no controlled studies of therapeutic intervention in humans are available, almost all of the current information is based on animal research.

Antimicrobial stewardship is the systematic effort to educate and persuade prescribers of antimicrobials to follow evidence-based prescribing, in order to stem antibiotic overuse, and thus antimicrobial resistance. AMS has been an organized effort of specialists in infectious diseases, both in Internal Medicine and Pediatrics with their respective peer-organizations, hospital pharmacists, the public health community and their professional organizations since the late 1990s. It has first been implemented in hospitals. In the U.S., within the context of physicians' prescribing freedom, AMS had largely been voluntary self-regulation in the form of policies and appeals to adhere to a prescribing self-discipline until 2017, when the Joint Commission prescribed that hospitals should have an Antimicrobial Stewardship team, which was expanded to the outpatient setting in 2020.

References

  1. 1 2 3 Ferguson, John (1 April 2004). "Antibiotic prescribing: how can emergence of antibiotic resistance be delayed?". Australian Prescriber. 27 (2): 39–42. doi: 10.18773/austprescr.2004.037 .
  2. 1 2 Babar, Zaheer-Ud-Din (2019). Encyclopedia of Pharmacy Practice and Clinical Pharmacy. Academic Press. p. 733. ISBN   978-0-12-812736-0.
  3. 1 2 Burrell, Anthony R; McLaws, Mary‐Louise; Fullick, Mary; Sullivan, Rosemary B; Sindhusake, Doungkamol (February 2016). "SEPSIS KILLS: early intervention saves lives". Medical Journal of Australia. 204 (2): 73. doi:10.5694/mja15.00657. PMID   26821106. S2CID   3959230.