Antimicrobial resistance prevention

Centers for Disease Control and Prevention. Antimicrobial Resistance. Home page www.cdc.gov/drugresistance/community/ faqs.htm accessed November 2005. 

European Centre for Disease Prevention and Control (ECDC) (2011) Available from http // ecdc.europa.eu/en/healthtopics/antimicrobial resistance/Pages/index.aspx30 Aug 2011... 

The treatment of HP has become increasingly difficult due to the frequency of antibiotic resistance and recurrence after successful treatment. In Peru, the recurrence rate of the infection is as high as 73% even after successful eradication. In this instance, recurrence is not attributed to antibiotic resistance but to re-infection of patients. In the United States, resistant HP is also of concern. The Helicobacter pylori Antimicrobial Resistance Monitoring Program (HARP) is a multicenter US network that tracks HP patterns of resistance. In 2004, HARP reported that 34% of 347 HP isolates tested were resistant to one or more antibiotics commonly used to treat HP infections.In the US, most antibiotic resistance is associated with metronidazole and clarithromycin, both standard treatment options for HP. Thus, antibiotic resistance and high re-infection rates strongly argue for the development of new therapeutic modalities to prevent and treat HP infections worldwide. 

The use of an antagonistic antimicrobial combination does not preclude other potential beneficial interactions. For example, rifampin may antagonize the action of anti-staphylococcal penicillins or vancomycin against staphylococci. However, the aforementioned antimicrobials may prevent the emergence of resistance to rifampin. 

Based on this understanding, it might be possible to develop effective methods to contain antimicrobial resistance in different settings. This will require close cooperation between sectors involved in food hygiene, prevention and control of diseases transmitted from animals to humans, hospital infection control, resistance... 

Kollef MH, Micek ST. Strategies to prevent antimicrobial resistance in the intensive care unit. Crit Care Med. 2005 33 1845-1853. 

Warren DK, Hill HA, Merz LR, Kollef MH, Hayden MK, Fraser VJ, Fridkin, SK. Cycling empirical antimicrobial agents to prevent emergence of antimicrobial-resistant Gram-negative bacteria among intensive care unit patients. Crit. Care Med. 2004 32 2450-2456. 

Shlaes DM, Gerding DN, John JE Jr, et al. Society for Healthcare Epidemiology of America and Infectious Diseases Society of America Joint Committee on the Prevention of Antimicrobial Resistance Guidelines for the prevention of antimicrobial resistance in hospitals. Infect Control Hosp Epidemiol 1997 18 275-291. 

In those patients for whom prior eradication therapy has been unsuccessful or in individuals who exhibit antimicrobial resistance, quadruple therapy may be contemplated. Diagnosis of clarithromycin resistance can be done by sequencing the specific region of the 23S RNA where a point mutation results in prevention of drug binding. 

Tannins Astringent condensed polyphenolic compounds present in some cereals such as bird-resistant sorghums that are antinutritional because they bind digestive enzymes and dietary proteins lowering feed efficiency. Tannins are also antimicrobial and prevent grain from sprouting in the field. Today, tannins are viewed as potent antioxidants and nutraceuticals. The tannins associated with hops bind proteins, decreasing beer haze and, upon oxidation, form colored compounds necessary in beer. 

Newer antimicrobials have not demonstrated superiority in the prevention of SSI and should be reserved for treatment only. Carbapenems, antipseudomonal penicillins, and third-or fourth-generation cephalosporins are not appropriate antibiotics for surgical prophylaxis. Overuse of these antibiotics may contribute to collateral damage and the development of bacterial resistance. 

Cefazolin or cefuroxime are appropriate for prophylaxis in cardiothoracic and vascular surgeries. In the case of 3-lactam allergy, vancomycin or clindamycin are advised. Debate exists on the duration of antimicrobial prophylaxis. The National Surgical Infection Prevention Project cites data that extending prophylaxis beyond 24 hours does not decrease SSI rates and may increase bacterial resistance.1 American Society of Health-System Pharmacists guidelines from 1999 allow for the continuation of prophylaxis for up to 72 hours.22 Duration of therapy should be based on patient factors and risk of development of an SSI. SSIs are rare after cardiothoracic operations, but the potentially devastating consequences lead some clinicians to support longer periods of prophylaxis. 

Montecalvo MA Ramoplanin A novel antimicrobial agent with the potential to prevent vancomycin-resistant enterococcal infection in high-risk patients. J Antimicrob Chemother 2003 51(suppl 3) 31—35. 

Integration of both pharmacokinetic and pharmacodynamic properties of an agent is important when choosing antimicrobial therapy to ensure efficacy and prevent resistance. Antibiotics may demonstrate concentration-dependent (aminoglycosides and fluoroquinolones) or time-depen-dent (/l-1 acta ms) bactericidal effects. 

Microbial resistance to established organic antibiotics is a potentially serious problem and provides an impetus for the development of novel antimicrobial metal compounds. The potency of Ag(I) ions is well known—but how does Ag(I) kill a bacterium Much current attention is focused on Bi(III) on account of its ability to kill Helicobacter pylori, an organism which prevents ulcers from healing. Bis-muth(III) chemistry has many unusual features a variable coordination number, strong bonds to alkoxide ligands, the stereochemical role of its 6s2 lone pair, facile formation of polymers, and dual hard and soft character. 

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