Management Of Anaerobic Infections Research Articles

Recent Trends in Antimicrobial Resistance among Anaerobic Clinical Isolates.

Anaerobic bacteria are normal inhabitants of the human commensal microbiota and play an important role in various human infections. Tedious and time-consuming, antibiotic susceptibility testing is not routinely performed in all clinical microbiology laboratories, despite the increase in antibiotic resistance among clinically relevant anaerobes since the 1990s. β-lactam and metronidazole are the key molecules in the management of anaerobic infections, to the detriment of clindamycin. β-lactam resistance is usually mediated by the production of β-lactamases. Metronidazole resistance remains uncommon, complex, and not fully elucidated, while metronidazole inactivation appears to be a key mechanism. The use of clindamycin, a broad-spectrum anti-anaerobic agent, is becoming problematic due to the increase in resistance rate in all anaerobic bacteria, mainly mediated by Erm-type rRNA methylases. Second-line anti-anaerobes are fluoroquinolones, tetracyclines, chloramphenicol, and linezolid. This review aims to describe the up-to-date evolution of antibiotic resistance, give an overview, and understand the main mechanisms of resistance in a wide range of anaerobes.

Nurse Practitioners' Attitudes, Perceptions, and Knowledge About Antimicrobial Stewardship

BackgroundAntimicrobial resistance is an urgent public health problem. There is very limited information regarding nurse practitioners' attitudes, perceptions, and knowledge about antibiotic use and resistance. MethodsWeb-based anonymous survey in a university-affiliated hospital. ResultsMost respondents agreed that antimicrobial resistance is a problem locally and nationally, were concerned about resistance in the community when prescribing antibiotics, and agreed that more appropriate use of antibiotics would decrease resistance. There is a paucity of knowledge in the management of anaerobic infections and resistant gram-negative bacteremia. ConclusionIncorporating nurse practitioners into antimicrobial stewardship programs could improve evidence-based practices and antimicrobial use.

Antimicrobial resistance and the management of anaerobic infections

Management of anaerobic infections encompasses surgical procedures, antibacterial therapy and adjuncts. At present, metronidazole, penems, β-lactam/β-lactamase inhibitor combinations and chloramphenicol have the highest activity against obligate anaerobes. Tigecycline is a promising new agent. Other antibacterials (e.g., nitazoxanide, moxifloxacin, garenoxacin and ramoplanin) and nonantibiotic agents show potential but need further investigation. The patient’s characteristics, mixed anaerobic/aerobic infections, infection sites, bacterial resistance patterns, bactericidal activity of agents and their pharmacokinetics, toxicity and influence on the normal flora should be considered. Susceptibility patterns of anaerobes have become less predictable owing to increasing antibacterial resistance. Emergence of highly virulent or multidrug-resistant strains is challenging the current therapy. To counteract these trends, regular resistance surveillance in anaerobes, rational antibiotic use and evaluation of new treatment alternatives are important.

The role of anaerobic bacteria in upper respiratory tract and other head and neck infections

Anaerobes are common pathogens in chronic upper respiratory tract and head and neck infections. They can be recovered in chronic otitis media and sinusitis, play a role in tonsillitis, and predominate in complications of these infections, causing deep oral and neck infections and abscesses. In addition to their direct pathogenicity, they play an indirect role through the production of the enzyme beta-lactamase, "shielding" non-beta-lactamase-producing bacteria from penicillins. Failure to provide adequate therapy against anaerobes may lead to clinical failures. Management of anaerobic infection is complicated by the slow growth of these organisms, by their polymicrobial nature, and by their growing resistance to antimicrobials. Antimicrobials are often the only form of therapy needed, but surgical approach is needed in some cases. Because anaerobes often are mixed with aerobic organisms, the antimicrobials given should provide adequate coverage against all pathogens.

The Management of Anaerobic Infection in Extensive Burns

A survey of 300 patients with burns covering more than 30 per cent of the body surface area indicated that 33 patients had proven wound infection with anaerobic bacteria and 11 patients showed positive blood cultures. Although metronidazole was the anti-bacterial agent of choice for treating these 33 patients, treatment was not always successful since 7 patients died. The most common sites of infection were the perineum and upper parts of the legs.

The management of anaerobic infection in extensive burns

A survey of 300 patients with burns covering more than 30 per cent of the body surface area indicated that 33 patients had proven wound infection with anaerobic bacteria and 11 patients showed positive blood cultures. Although metronidazole was the anti-bacterial agent of choice for treating these 33 patients, treatment was not always successful since 7 patients died. The most common sites of infection were the perineum and upper parts of the legs.

Antimicrobial drugs used in the management of anaerobic infections in children.

Optimum antimicrobial therapy effective against anaerobes is required to rapidly resolve infections due to these organisms and to prevent serious complications. Selection of antimicrobial therapy should be based on clinical experience and presumptive evidence until culture and sensitivity tests are available. If an abscess should develop, surgical drainage (when possible) is of paramount importance. Antimicrobial therapy for anaerobic infections should usually be given for prolonged periods because of the tendency for relapse, and should include coverage for aerobic bacteria whenever they are present. Penicillin G remains the drug of choice for most anaerobic infections except those caused by beta-lactamase-producing Bacteroides spp. such as B. fragilis and B. melaninogenicus, and some strains of Fusobacterium varium, which can be resistant. Other antimicrobials which are available for treatment of anaerobic infections in paediatric patients, and are generally active against B. fragilis, are carbenicillin, ticarcillin, chloramphenicol, clindamycin and cefoxitin. Experience in the use of metronidazole suggests that it could be a very valuable antimicrobial agent in the treatment of anaerobic infections. Experience with synergistic antimicrobial combinations in the treatment of anaerobic infections is limited; only experimental data are available suggesting synergism between penicillin and aminoglycosides against some Bacteroides spp. beta-Lactamase-producing anaerobic bacteria may protect other penicillin-susceptible bacteria in mixed infections. This phenomenon may explain penicillin failure in eradicating mixed infections.

Recent developments in the management of anaerobic infections.

Anaerobic bacteria are recognized with increasing frequency as etiologic agents in a variety of infectious diseases. The pathogenic significance of these microbes is supported by experimental studies with animals, chemotherapeutic trials, and definition of specific virulence factors by microbial analysis. In vitro sensitivity tests show that many clinically significant anaerobic species are resistant to penicillin; susceptibility to an expanding array of alternative antimicrobial agents is quite variable. Nevertheless, clinical trials suggest that several antibiotic regimens are equally effective. These studies provide guidelines for empiric selection of agents, although in vitro studies or the unique properties of some drugs must be considered in occasional cases. Several commonly accepted tenets held in the past may now be challenged: some abscesses do not require surgical drainage; plasmids conferring resistance to clindamycin in Bacteroides fragilis appear prevalent in some institutions; clindamycin may be the preferred agent for treatment of serious anaerobic pulmonary infections; and metronidazole is the only new agent advocated for anaerobic infections that offers potential advantages over prior agents.

Problem Pathogens in Serious Infections

On perusing these articles for this special issue on infection, one is made aware that (1) serious infections are still a worldwide problem, (2) the understanding and management of these infections depends on the careful consideration of microbiologic, pathophysiologic, and pharmacologic conditions, (3) investigators studying the problems have a somewhat different outlook, depending on whether they are surgeons, clinical microbiologists, or infectious disease specialists, and (4) there are diverse approaches to these problems in different parts of the world. By blending viewpoints and concepts, it is hoped that physicians will enhance their ability to treat patients with serious infections. Sydney M. Finegold, MD, from Los Angeles, has carefully considered the pathogenic anaerobes in a scholarly review that emphasizes virulence factors and the ways that they interact with host defenses. He also gives us a clear overview of the approach to the diagnosis and management of anaerobic infections. Donald Kaye, MD,

The laboratory and the management of anaerobic infection.

The clinical laboratory has an important role in the management of anaerobic infection. By the macroscopic examination of specimens, with special attention paid to odour and fluorescence in ultra-violet light, by examination of Gram-stained films, and, when they are available, by the application of gas-liquid chromatography and specific immunofluorescence, they can provide a firm presumptive diagnosis. The isolation of anaerobes, possible by simple means, will confirm the diagnosis, and simple disk tests will guide definitive antibiotic treatment. More detailed patterns of antibiotic sensitivity of specific anaerobes will be provided by laboratories with special skills.

Medical consultation on surgical services: an annotated bibliography.

This bibliography provides a literature base for residents on medical consultation services and for internists performing consultations in a field that is difficult to research through Index Medicus.

Diagnosis and management of anaerobic infections.

Diagnosis and management of anaerobic infections.

Letter: Relative frequencies of anaerobes.

Excerpt To the editor: In the UCLA Conference on the management of anaerobic infections (Ann Intern Med83:375-389, 1975) by Finegold and coworkers it is erroneously stated (p. 384) thatBacteroides ...

Binding of rubiflavin to deoxyribonucleic acid in relation to antibacterial action.

In order to determine the therapeutic value of penicillins in the management of anaerobic infections caused by Bacteroides fragilis, the antibacterial activity of penicillin G, ampicillin, and carbenicillin against 10 strains of B. fragilis subsp. fragilis, isolated from clinical material, was studied. This was undertaken by using a triple-layer technique, enzymatic inactivation of the antibiotics, and an automatic colony counter, which allowed a quantitative and a qualitative approach to the problem. Results indicated in vitro bactericidal activity with 40 mug of penicillin G, ampicillin, and carbenicillin per ml against all strains tested. However, carbenicillin had the most rapid activity.