Antibiotic resistance

Widespread resistance problems exist today in a global sense because of the incorporation of antibiotics with a high resistance potential into animal feeds and because of the uncontrolled use of antibiotics with a high resistance potential in the clinical setting. The only proven method of controlling nonoutbreak resistance problems in hospitals is to limit the hospital formulary to antibiotics with little or no resistance potential. The control of multiresistant organisms in outbreaks occurring in hospitals is best contained using appropriate infection control containment measures. Physicians treating infections in the community, with all other factors being equal, should preferentially select antibiotics with a low resistance potential. The titles and headings of much of the resistance literature are misleading. Articles should not contain fluoroquinolone resistant in the title when ciprofloxacin-resistant organisms are described. Many articles concerning penicillin-resistant pneumococci are entitled fluoroquinolone-resistant S. pneumoniae. These articles describe ciprofloxacin-resistant S. pneumoniae and not resistance to other fluoroquinolones. The same error is perpetuated in describing third-generation cephalosporins and carbapenems. Virtually all of the resistance problems associated with third-generation cephalosporins and carbapenems are due to ceftazidime or imipenem. More precise titling in the literature would remind physicians that antibiotic resistance is related to a specific agent and not class phenomena.     

Antibiotic resistance in cancer patients

Bacterial infection is one of the most frequent complications in cancer patients and hematopoietic stem cell transplant recipients. In recent years, the emergence of antimicrobial resistance has become a significant problem worldwide, and cancer patients are among those affected. Treatment of infections due to multidrug-resistant (MDR) bacteria represents a clinical challenge, especially in the case of Gram-negative bacilli, since the therapeutic options are often very limited. As the antibiotics active against MDR bacteria present several disadvantages (limited clinical experience, higher incidence of adverse effects, and less knowledge of the pharmacokinetics of the drug), a thorough acquaintance with the main characteristics of these drugs is mandatory in order to provide safe treatment to cancer patients with MDR bacterial infections. Nevertheless, the implementation of antibiotic stewardship programs and infection control measures is the cornerstone for controlling the development and spread of these MDR pathogens.     

Antibiotic resistance in veterinary medicine

ABSTRACT:

Antibiotics are essential medicines in the veterinary practice to help preserve the health and welfare of our animals. However, antibiotic resistance is an important topic of discussion for both the medical and veterinary professions. It is something we clearly all need to take seriously – and veterinary nurses need to be aware of the facts, to help them guide clients on responsible antibiotic use, once the vet has prescribed antibiotics for the treatment of a condition. You might need to explain why an antibiotic has not been prescribed, for example, or to impress upon a client the importance of finishing the prescribed course.     

Antibiotic resistance in the institutionalized elderly

Geriatric patients frequently are cared for in long term care facilities (LTCFs), which are now a major component of our health care delivery system. Nearly half of the 2.2 million people who turned 65 years old in 1990 will enter an LTCF at least once before they die. Infections are one of the principal causes of morbidity and mortality in LTCFs. Because LTCFs are a less costly alternative to hospitalization, clinicians are treating many serious infections in the nursing home. As a result of antibiotic use, LTCFs will increasingly be recognized as sources of organisms resistant to multiple antibiotics. b-Lactams are a valuable class of potent antimicrobials with broad-spectrum activity against Gram-negative and Gram-positive organisms. The safety and efficacy of this class of antibiotics make them easy choices for empiric treatment of infections in the elderly. Unfortunately, excessive use of these antibiotics has created serious threats to our therapeutic armamentarium: the emergence of methicillin-resistant Staphylococcus aureus and of Gram-negative pathogens resistant to third-generation cephalosporins such as cefotaxime, ceftazidime, and ceftriaxone. Of these third-generation cephalosporins, resistance to ceftazidime is most frequently recognized. The major mechanism responsible for ceftazidime resistance in Gram-negative bacteria is the production of b-lactamases. This article summarizes the diversity of b-lactamases, highlights the important enzymes that confer ceftazidime resistance in LTCFs, and details some methods used to identify and characterize these enzymes. A clear challenge is to apply these techniques to epidemiologic and molecular studies conducted in LTCFs.     

生物膜中白念珠菌的耐药性研究

白念珠菌（Canida albicans）是人类最常见的条件致病真菌,健康者带菌率以口腔最高,约80％。当机体免疫力下降或使用免疫抑制剂时,白念珠菌可导致严重的感染性疾病,在美国医院感染中列第4位,其病死率为30％～70％。研究发现,在难治性白念珠菌感染的病灶中大多存在生物膜。自然界中99％微生物以生物膜的形式存在,65％人类感染性疾病与生物膜相关。     

Antibiotic resistance in the intensive care unit

The increase in antibiotic resistance over the past 10 years can be traced to several factors. This includes exogenous transmission of bacteria, usually by hospital personnel. The use of potent antibiotics also can select for resistant bacteria initially present in low quantities. Strategies to reduce antibiotic resistance can be tailored to specific outbreaks in a given ICU. General strategies for reducing antibiotic resistance, on the other hand, include varying the agents used in the ICU over time. Reduction of the duration of therapy may prove to be another method of reducing antibiotic resistance.     

857株解脲脲原体耐药性分析

目的了解本院2004年泌尿生殖道解脲脲原体感染状况及对常用抗菌药物的耐药情况，以期对临床治疗有所帮助。方法对我院妇科、皮肤科送检的泌尿生殖道分泌物采用培养、药敏一体化的方法，监测9种抗菌药对解脲脲原体的抑制作用。结果857份送检标本中检出解脲脲原体369株，检出率为43．1％；总体耐药率4．6％～43．6％，其中喹诺酮类耐药率最高，多西环素、米诺环素耐药率最低。结论泌尿生殖道支原体感染以解脲脲原体为主，多西环素、米诺环素对之有良好作用，其次为克拉霉素、交沙霉素。     

Antibiotic resistance in Enterococcus faecium clinical isolates

The worldwide ratio of Enterococcus faecalis-Enterococcus faecium infections is currently changing in favor of E. faecium. Intrinsic and acquired antimicrobial resistance traits of this latter species can explain this evolution as well as the diffusion of hospital-adapted strains belonging to the clonal complex CC17. Like other enterococci, E. faecium is naturally resistant to cephalosporins and aminoglycosides (at low level). Because of its high genome plasticity, it can also acquire numerous other resistances. It is noteworthy that most modern isolates of E. faecium are highly resistant to ampicillin while a non-negligible proportion of them (depending on geographical locations) are resistant to glycopeptides (especially in the USA). Even if resistance to newer antimicrobial agents (linezolid, daptomycin, tigecycline) is still uncommon, some clinical isolates with reduced susceptibility or resistance have already been reported and better understanding of resistance mechanisms is needed for prediction and prevention of their dissemination.     

Antibiotic resistance amongst various types of Haemophilus species

Antibiotic resistance of haemophili was studied as part of an epidemiological survey on the distribution of biotypes of Haemophilus influenzae and H. parainfluenzae from various clinical isolates. Biotype II H. influenzae was the commonest biotype isolated but biotype III yielded the most frequent antibiotic resistance. Resistance to ampicillin (15.1%) was commonest, followed by sulphonamide, tetracycline, trimethoprim and chloramphenicol. Multi-resistant strains were found including one capsular type b (biotype III) strain. H. parainfluenzae biotype I was the commonest isolate but biotype II was most frequently resistant to antibiotics. The resistance pattern followed that of H. influenzae except for chloramphenicol to which resistance was commoner than for trimethoprim.     

Antibiotic resistance in the intensive care unit setting

Antibiotic resistance is an important factor influencing clinical outcome for patients in intensive care units. It is also associated with increased healthcare costs resulting from prolonged patient stays. The problem of antibiotic resistance is particularly acute in intensive care units because they house seriously ill patients who are predisposed to infection, as a result of which, antibiotic use is extremely common. Strategies for controlling resistance in intensive care units have focused on attempting to reduce unnecessary antibiotic use, while at the same time ensuring adequate antibiotic cover is provided. The formulation of policies for the effective use of antibiotics in individual intensive care units requires a multidisciplinary approach, entailing regular epidemiological surveillance, together with input from critical care specialists, infectious disease specialists and pharmacists.