Antibiotic prophylaxis to prevent nosocomial infections in patients in intensive care units: evidence that struggle to convince practising clinicians

BACKGROUND: Pneumonia is an important cause of mortality in intensive care units. The incidence of pneumonia in such patients ranges between 7 and 40%, and the crude mortality from ventilator associated pneumonia may exceed 50%. Although not all deaths in patients with this form of pneumonia are directly attributable to pneumonia, it has been shown to contribute to mortality in intensive care units independently of other factors that are also strongly associated with such deaths. OBJECTIVES: The objective of this review was to assess the effects of antibiotics for preventing respiratory tract infections and overall mortality in adults receiving intensive care. Search strategy. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (issue 3, 2003), which contains the Acute Respiratory Infections (ARI) Group specialised trials register; MEDLINE (January 1966 to September 2003); EMBASE (January 1990 to September 2003); proceedings of scientific meetings and reference lists of articles from January 1984 to December 2002. We also contacted investigators in the field. Selection criteria. Randomised trials of antibiotic prophylaxis for respiratory tract infections and deaths among adult intensive care unit patients. Data collection and analysis. At least two reviewers independently extracted data and assessed trial quality. RESULTS: Overall 36 trials involving 6922 people were included. There was variation in the antibiotics used, patient characteristics and risk of respiratory tract infections and mortality in the control groups. In 17 trials (involving 4295 patients) that tested a combination of topical and systemic antibiotic, the average rates of respiratory tract infections and deaths in the control group were 36% and 29% respectively. There was a significant reduction of both respiratory tract infections (odds ratio 0.35, 95% confidence interval [CI] 0.29-0.41) and total mortality (odds ratio 0.78, 95% CI 0.68-0.89) in the treated group. On average 5 patients needed to be treated to prevent one infection and 21 patients to prevent one death. In 17 trials (involving 2664 patients) that tested topical antimicrobials alone (or comparing topical plus systemic versus systemic alone) the rates of respiratory tract infections and deaths in the control groups were 30 and 26% respectively. There was a significant reduction of respiratory tract infections (odds ratio 0.52, 95% CI 0.43-0.63), but not in total mortality (odds ratio 0.97, 95% CI 0.81-1.16) in the treated group. CONCLUSIONS: A combination of topical and systemic prophylactic antibiotics reduces respiratory tract infections and overall mortality in adult patients receiving intensive care. A treatment based on the use of topical prophylaxis alone reduces respiratory infections, but not mortality. The risk of occurrence of resistance as a negative consequence of antibiotic use was appropriately explored only in the most recent trial by de Jonge, which did not show any such effect.     

Major change in the use of antibiotics following a national programme: Swedish Strategic Programme for the Rational Use of Antimicrobial Agents and Surveillance of Resistance (STRAMA).

In order to reduce inappropriate use of antibiotics and to counteract the increase in antimicrobial resistance in community-acquired and nosocomial infections, a national project was initiated in Sweden in 1994: the Swedish Strategic Programme for the Rational Use of Antimicrobial Agents and Surveillance of Resistance. In the first years the project focused on inappropriate prescribing of antibiotics to children with respiratory tract infections and on the surveillance of resistance in pneumococci. Statistics on antibiotic sales on a national and county level and for different age-groups were studied. Between 1993 and 1997 antibiotic prescribing was reduced by 22%, from 16.3 to 13.0 defined daily doses (DDD) per 1000 inhabitants/d. The reduction was most pronounced for children, 0-6-y-old, from 15.7 to 9.7 DDD/1000 children/d. Macrolides and amoxicillin/co-amoxyclav decreased most. There were large variations in antibiotic sales in different counties, and a decrease was also noted in counties starting from a low level. In the county with the highest sales in 1993, antibiotic prescribing to children was reduced by 40%. The national frequency of penicillin-non-susceptible pneumococci (MIC > or =0.1 mg/l) has not increased during the 1990s and the increasing incidence in southern Sweden seems to have been curtailed. During the period that the project has been running, a major change in the use of antibiotics, especially for pre-school children, has been achieved.     

beta-lactam-antibiotics in the treatment of community-acquired respiratory tract infections with penicillin-resistant pneumococci

Streptococcus pneumoniae is still the most important pathogen of community-acquired respiratory tract infections. During the last decades in many countries an increase in the spread of antibiotic resistant strains (e. g. against beta-lactams, macrolides, tetracyclin) was observed. Resistance against penicillin is often associated with resistance against macrolides and other antibiotic classes. In Germany surveillance studies including isolates from patients with community-acquired respiratory tract infections have shown that about 14 % of strains show a reduced susceptibility against penicillin (MIC-values 0.12 - 1 mg/L) and up to 4 % are highly resistant against penicillin (MIC >/= 2 mg/L). Resistance against tetracycline or macrolides was detected in up to 12 and 15 % of strains, respectively. According to the treatment guidelines of the Paul-Ehrlich-Gesellschaft für Chemotherapie and the Deutschen Atemwegsliga penicillins and cephalosporins are recommended as first line antibiotics for the treatment of community-acquired respiratory tract infections. As pneumococcal strains with reduced susceptibility against penicillin show often also a reduced susceptibility against cephalosporins the questions arises which beta-lactam antibiotics should still be used in empirical treatment of such strains. beta-Lactam-antibiotics highly differ in their in-vitro-activity against S. pneumoniae and their pharmacokinetic properties. In different models is has been demonstrated for beta-lactams that an adequate clinical and bacteriological efficacy is achievable when the serum levels of the free, i. e. not protein bound fraction of drug exceeds the MIC of the pathogen for at least 40 to 50 % of the dosing interval (T > MIC). In a clinical situation where pneumococci with reduced susceptibility against penicillin cannot be ruled out, only beta-lactam antibiotics with favourable pharmacological properties (good in-vitro activity, high and long lasting serum levels) should be used for treatment.     

Towards individually tailored empiric antibiotic therapy in febrile granulocytopenic patients

The objective of this retrospective analysis was to study the possibility of a treatment strategy for febrile, granulocytopenic patients based on relative infective risks. Data from 441 adult febrile, granulocytopenic patients treated initially with antibacterial monotherapy were reassessed in terms of infection risk and outcome. Two different risk-groups were identified, namely those without and those with a clinical focus of infection (e.g. the respiratory tract and skin and soft tissue). Patients with a focus took longer to respond (4-8 days to defervesce) than those with unexplained fever, urinary tract infection or bacteraemia (2-3 days to defervesce). Patients with respiratory tract and skin and soft tissue infections received additional antibiotics more frequently (greater than 15% versus less than 10%) and were treated for a longer period (50% greater than or equal to 9 versus less than or equal to 8 days). More often the bone marrow had recovered at the time of response (48% versus 65%). These data suggest that a differentiated approach in the selection of initial antibiotics may be feasible, based upon continuous assessment of the patient's clinical condition. Antibiotic therapy may be postponed in patients without a focus of infection who show slowly increasing temperature. Patients with upper respiratory tract and skin and soft tissue infections may benefit from initial addition of penicillin and a glycopeptide, respectively. In cases of lower respiratory infections, antifungal therapy should be considered at an early stage.     

Infections and antibiotic prescribing in Swedish nursing homes: a cross-sectional study

The aim of this study was to present and assess the treatment of infections in Swedish nursing homes. It included 58 nursing homes with 3002 residents. During 3 months, nurses in the nursing homes recorded all infections requiring a physician's opinion. Of the 889 infectious episodes, 84% were treated with antibiotics. Many of the antibiotics were issued after indirect contact with the physician (38%). Indications for antibiotics were in 55% of the cases urinary tract infections (UTI), in 17% skin and soft-tissue infections and in 15% respiratory tract infections (RTI). The most common antibiotics were penicillins (38%), followed by quinolones (23%) and trimethoprim (18%). For the major indication, lower UTI in women, half of the cases were not treated according to the recommendations. The main concerns were length of treatment and overprescribing of quinolones. For the second major diagnosis, pneumonia, the high use of doxycycline could be questioned. Continuing education on infections and their treatment in nursing homes is needed. Training should preferably include both physicians and nurses as a high proportion of antibiotics is issued without direct contact with the physician.     

Appropriate antibiotic use according to diagnoses and bacteriological findings: report of 12 point-prevalence studies on antibiotic use in a university hospital

The objective of this study was to evaluate antibiotic use in relation to diagnoses and bacteriological findings in a 600-bed Norwegian university hospital. Twelve point-prevalence studies of antibiotic use were conducted between 1996 and 1999. In the point-prevalence studies, 1,096 of 6,588 adult patients (16.6%) used on average 1.25 antibiotics each. Of the patients who received antibiotics, 35% were treated for hospital-acquired infections. Lower respiratory tract and urinary tract infections accounted for more than half of all antibiotic use. Pencillins represented 54% of antibiotic use, cephalosporins 9%, quinolones 6% and antifungal agents 0.7%. The prescribed daily doses for the penicillins were 2-3 times higher than the defined daily doses. Bacteriological samples were obtained from 929 (85%) patients. Compliance with the guidelines was > 90% and was highest when the results of bacteriological samples were positive. Good compliance led to low prevalence of antibiotic use and the use of narrow-spectrum antibiotics.     

Desire for antibiotics and antibiotic prescribing for adults with upper respiratory tract infections

OBJECTIVE: Prior studies have shown that 60% to 75% of adults with upper respiratory tract infections want antibiotics. More recent research indicates declines in antibiotic prescribing for upper respiratory tract infections. To investigate whether there has been a comparable decrease in patients' desire for antibiotics, we measured the proportion of adults with upper respiratory tract infections who wanted antibiotics in the winter of 2001-2002. We also sought to identify factors independently associated with wanting antibiotics and antibiotic prescribing. DESIGN: Prospective survey of adults with upper respiratory tract infections prior to visiting an acute care clinic from November 2001 to February 2002. MEASUREMENTS AND MAIN RESULTS: Thirty-nine percent of 310 patients wanted antibiotics. Many patients wanted relief from symptoms (43%) or pain (24%) and many patients expected to receive a diagnosis (49%) or reassurance during the visit (13%). In multivariable modeling, independent predictors of wanting antibiotics were prior antibiotic use (odds ratio [OR], 2.4; 95% confidence interval [CI], 1.3 to 4.7) and current smoking (OR, 3.1; 95% CI, 1.3 to 7.3). Physicians prescribed antibiotics to 46% of patients who wanted antibiotics and 29% of patients who did not want antibiotics (P=.01). In multivariable modeling, wanting antibiotics was an independent predictor of antibiotic prescribing (OR, 2.1; 95% CI, 1.1 to 4.4). CONCLUSIONS: Only 39% of adults seeking care for upper respiratory tract infections wanted antibiotics, less than in previous studies. In continuing efforts to break the cycle of inappropriate antibiotic use, physicians should not assume that most patients with upper respiratory tract infections want antibiotics.     

Upper respiratory tract infections in general practice: diagnosis,antibiotic prescribing,duration of symptoms and use of diagnostic tests

A diagnosis/antibiotic prescribing study was performed in 5 counties in Sweden for 1 week in November 2000. As part of this study, the characteristics and clinical management of patients with upper respiratory tract infections (n = 2899) in primary care were analyzed. Almost half of the patients were aged < 15 y and one-fifth of the patients consulted out of hours. Of all patients seeking primary care for upper respiratory tract infections, 56.0% were prescribed an antibiotic. Almost all patients who were given the diagnoses streptococcal tonsillitis, acute otitis media or acute sinusitis were prescribed antibiotics, compared to 10% of patients with common cold or acute pharyngitis. The most frequently prescribed antibiotic was penicillin V (79.2%) and this was even more pronounced out of hours, when the diagnoses otitis media and streptococcal tonsillitis were more frequently used. In patients with common cold and acute pharyngitis, the percentage who received antibiotics increased with increasing length of symptoms and increasing CRP levels. In patients with acute pharyngitis or streptococcal tonsillitis, antibiotics were prescribed less frequently provided streptococcal tests were performed. The management of patients with upper respiratory tract infections in general practice seems to be in good agreement with current Swedish guidelines. However, the study indicates some areas for improvement. The diagnosis of acute sinusitis seems to have been overestimated and used only to justify antibiotic treatment.     

In vitro activity of the new ketolide telithromycin and other antibiotics against Streptococcus pneumoniae in Belgium

In Belgium more than 17% of the invasive pneumococci are not susceptible to penicillin, and more than 38% not to macrolides. The most prevalent mechanism of macrolide resistance in Europe is modification of the drug target site leading to cross-resistance to lincosamides and group B streptogramines (MLSB resistance). Telithromycin is the first antibiotic of the family of ketolides, which differ from erythromycin by having a 3-keto group instead of the neutral sugar L-cladinose. We tested the susceptibility of 637 pneumococci, recently isolated from patients in Belgium, to telithromycin and five other antibiotics. Data generated by this study show that telithromycin inhibits 98.4% of pneumococci at a breakpoint concentration of 1 mg/L in spite of a high percentage (> 30%) of strains with the MLSB constitutive type of resistance. Susceptibilities to the five comparator drugs were: penicillin (81.8%), tetracycline (67.0%), levofloxacin (98.9%), erythromycin (61.5%) and clindamycin (66.6%). Consequently telithromycin looks to have considerable potential for the empiric treatment of community-acquired respiratory tract infections.     

老年下呼吸道感染患者肺炎克雷伯菌和大肠埃希菌耐药性分析

目的：监测老年下呼吸道感染患者肺炎克雷伯菌和大肠埃希菌的耐药性。为临床合理应用抗生素提供依据。方法：对我院下呼吸道感染患者中分离出的肺炎克雷伯菌和大肠埃希菌240株，以Kirby-Bauer(K-B)琼脂扩散法作药敏试验；以美国临床实验室标准委员会（NCCLS）1999年推荐的表型确认试验检测超广谱β－内酰胺酶（ESBLs）。结果：老年组和非老年组肺炎克雷伯菌和大肠埃希菌对14例抗生素的耐药率分别为阿莫西林93．2％和87．3％，哌拉西林57．1％和42．9％、头孢呋新51．4％和33．3％、头孢噻肟40．1％和17．5％、头孢他啶13．6％和3．2％、头孢曲松39．0％和17．5％、头孢哌酮37．3％和15．9％，头孢吡肟10．2％和3．2％、阿米卡星47．5％和34．9％，环丙沙星54．2％和38．1％、亚胺培南15．9％、头孢吡肟10．2％和3．2％、阿米卡星47．5％和34．9％、环丙沙星54．2％和38．1％，亚胺培南0和0、头孢哌酮／舒巴坦0和0、哌拉西林／三唑巴坦1．1％和0、头孢美唑9．6％和4．8％。78株肺炎克雷伯菌和大肠埃希菌被证实为产ESBLs菌，ESBLs检测出率为32．5％（78／240），其中老年组ESBLs检出率为38．4％（68／177），非老年组ESBLs检出率为15．9％（10／63）。亚胺培南，头孢哌酮／舒巴坦，哌拉西林／三唑巴坦和头孢美唑对产ESBLs菌的耐药率最低，分别为0、0、2．6％和12．8％。结论：老年下呼吸道感染患者肺炎克雷伯菌和大肠埃希菌的耐药率和ESBLs检出率均显著高于非老年患者；亚胺培南，头孢哌酮／舒巴坦、哌拉西林／三唑巴坦和头孢美唑是治疗由产ESBLs菌引起感染的有效抗生素。     

Antibiotic sensitivity pattern of the bacteria isolated from nosocomial infections in ICU

The incidence of nosocomial infections in ICU is 4-5 times greater than in general ward. Critically ill patients are always at higher risk of developing nosocomial infections with resistant strains. This study is an attempt to know the antibiotic sensitivity pattern of the common isolates in ICU. Samples comprising urine, blood, endotracheal secretions and throat swabs were collected from 102 ICU patients of them, 56 patients showed evidence of nosocomial infection (54.9%), from whom 120 different organisms were isolated. Antibiotic sensitivity test was done according to Kirby Bauer method. Klebsiella pneumoniae were the most prevalent isolates from respiratory tract infections followed by Proteus spp, Escherichia coli, Staphylococci spp. and Acinetobacter spp. The gram negative enteric bacilli were uniformly resistant to betalactam antibiotics as well as betalactam-betalactamase inhibitors. Resistance to Ciprofloxacin and Ceftriaxone ranged from 50-100% and 25-83.3% respectively. Staphylococci were 100% resistant to penicillin and tetracycline, 80% to cotrimoxazole, 60% to erythromycin and gentamicin and 40% to amikacin. Acinetobacter spp. were highly resistant to most of the antibacterial agents except gentamicin while Pseudomonas spp. showed 75% resistance to it. The increased prevalence of resistant organisms in ICU probably reflects lack of proper antibiotic policy resulting in prolonged and indiscriminate use of antimicrobial agent.     

Incidence and characteristics of antibiotic use in aged nursing home patients

OBJECTIVE. To measure the prevalence, incidence, types, and certain characteristics of antibiotics prescribed in nursing homes. DESIGN AND SETTING. Periodic survey over 1 year of patient charts in 53 stratified, randomly selected nursing homes in the state of Maryland. PATIENTS. All patients 65 years of age or more residing in these nursing homes on the first day of study. RESULTS. Of 4,165 patients in 53 nursing homes, records over the year were satisfactory in 3,899 patients in 52 nursing homes. The prevalence of antibiotic use on the first day of the study was 8%. Over the next 12 months, observations of more than one million patient-days revealed an incidence of 0.46 antibiotic courses/100 patient-days; 54% of the 3,899 patients received at least one antibiotic course. For presumed active infections, beta lactam antibiotics were the most commonly used, 54% of antibiotic orders. For all antibiotics, urinary tract infection was the most common indication, eliciting 36% of orders including 9% for asymptomatic bacteriuria. Skin, lower respiratory, and upper respiratory infections comprised 14%-17% each. Physicians prescribed 94% of courses but documented examinations of only 44% of patients at the outset of these courses. Consensus criteria for minimal diagnostic evaluation of four selected infections were met in only 11% of episodes of infection. Although the most serious infections tended to be better evaluated than others, 31% of the former were not noted to have been examined by a physician. Three percent of orders were for prophylaxis and two-thirds of these antibiotics were administered for more than 2 days. CONCLUSIONS. Antibiotics are frequently prescribed for aged nursing home patients, often in the absence of a physician's examination and other features commonly performed in evaluation of specific infectious diseases. More than one-fifth of antibiotics prescribed by presumed active infections were for two infections usually thought not to require antibiotic therapy, "viral" upper respiratory infection (13%) and asymptomatic bacteriuria (9%). To optimize antibiotic use in nursing homes, greater attention should be directed to appropriate durations of prophylaxis for urologic, dental, and minor surgical procedures; to standards for diagnostic evaluations of common infections; and to the roles of antibiotics in upper respiratory infections and in asymptomatic bacteriuria.     

Biologic therapies and infections in the daily practice of three Italian rheumatologic units: a prospective,observational study

Since the introduction of biologics, many concerns about the increased risk of infections have been reported and, to date, the real impact of infections on the daily practice in the rheumatologic centers is still largely unknown. In this work, we evaluated the infection rates associated with the use of biologics in a large cohort of patients. A prospective study, between January 2010 and December 2013, enrolling 731 rheumatic patients, was performed. Demographic and disease characteristics, therapies, comorbidities, and infectious events were recorded and statistically analyzed by multivariate analysis. Two-hundred thirty-five infectious episodes were observed in 28.4 % of patients. About total infections, bacteria were identified in 70.6 % of total cases and viruses in 18.3 %. The most common site of not-serious infection was the urinary tract. Duration of disease, longer follow-up, concomitant steroid therapy, and comorbidities were significantly associated with not-serious infection. In our cohort, 17 episodes fulfilled the criteria of serious infection and occurred in 17 different patients (2.3 %), the majority involving the lower respiratory tract. Serious infections were associated with the beginning of biologics in older age. Our prospective, observational study showed that, in daily practice, a lesser rate of serious as well as not-serious infections may be observed in rheumatic patients treated with biologics than those reported in previous papers. The most common sites of not-serious infections are both the urinary and the respiratory tracts, and for serious infections, the respiratory tract. When pathogens were isolated, we did not find any multidrug-resistant organism.     

Does the adoption of EUCAST susceptibility breakpoints affect the selection of antimicrobials to treat acute community-acquired respiratory tract infections?

ABSTRACT: BACKGROUND: In several European Countries, by the end of 2012, CLSI guidelines will be replaced by EUCAST. We compared antimicrobial susceptibility results of a large number of respiratory pathogens using both EUCAST and previously adopted CLSI criteria to evaluate the impact on susceptibility patterns and the possible consequences that could occur in clinical practice due to this replacement. For S. pyogenes and S. aureus, the interpretation of susceptibility data using the EUCAST criteria did not produce relevant changes in comparison to CLSI. Against S. pneumoniae, more restrictive EUCAST breakpoints could lead to increased benzylpenicillin and/or amoxicillin-clavulanate resistance rates, which in turn could translate in increased dosages of these antibiotics or usage of alternative agents for respiratory tract infections. Against S. pneumoniae, M. catarrhalis and H. influenzae, cefuroxime-axetil and cefaclor produced the most divergent results depending on the breakpoints adopted and these striking differences could lead to the revision of those guidelines suggesting these two cephalosporins as alternatives in the management of upper respiratory tract infections. DISCUSSION: Many differences exist between CLSI and EUCAST breakpoints. However, only in a few cases do these differences translate in major interpretive category discrepancies. In countries adopting more restrictive EUCAST breakpoints, clinicians should be aware of these discrepancies and that they could be faced with antibiotic-resistant respiratory pathogens more frequently than before. SUMMARY: The interpretive discrepancies between EUCAST and CLSI suggest that the discussion on the management of community-acquired respiratory tract infections is still open and further studies are desirable to better define the role of some antibiotics.     

呼吸道表皮葡萄球菌的分离、药敏及其意义

目的了解下呼吸道感染中表皮葡萄球菌药物敏感性及其临床意义。方法（１）对１９９０年～１９９６年间普通病房下呼吸道感染住院患者的合格痰标本进行培养、分离鉴定，研究表皮葡萄球菌分离率；（２）以纸片（ＫＢ）法或琼脂稀释法测定分离表皮葡萄球菌对常用抗生素的药物敏感性。结果（１）６２２８份痰标本中分离到细菌２６６０株，其中表皮葡萄球菌２５７株占９．７％，表皮葡萄球菌分离率为４．１％，在各病原菌中占第４位；（２）对２１种抗生素的药敏测定发现，除万古霉素外，表皮葡萄球菌对其它各抗生素均有耐药，耐药率在１５．２％～９８．１％，并存在多重耐药，其中亚胺培南、头孢噻吩、头孢哌酮为较敏感抗生素，耐药率分别为１７．１％、１８．７％和３０．０％，其它各抗生素的耐药率均在４８．３％以上，部分在８０％以上。结论表皮葡萄球菌在下呼吸道感染时分离率高，耐药性强，存在多重耐药，应引起重视。     

Infectious disease consultations and antibiotic usage in a Turkish university hospital.

OBJECTIVES: The aim of this study was to investigate the various features of infectious disease (ID) consultations and the usage of antibiotics in a Turkish university hospital. METHODS: A total of 395 consultation requests were recorded during a three-year period. RESULTS: The departments most frequently requesting the consultation services of the ID department were Orthopedics (29.6%), Neurology (18.5%), Cardiology (11.8%) and Internal Medicine (10.4%). The main reasons were for diagnosis of unexplained fever (42.3%) and for antibiotic modification according to culture results (18%). Diagnoses made by the ID consultant were pneumonia (16.7%), urinary tract infections (9.3%), bone and joint prosthesis infections (9.1%) and in 15.7% of the investigated patients, no infectious focus was determined. It was recognized that the use of antibiotics had already been initiated in the great majority of patients (67.1%) before the consultation request. While the current therapy was changed in 57.4% of these patients, antibiotics were not necessary for 9.8%. CONCLUSIONS: Since the most common diagnoses were respiratory and urinary tract or bone and joint prosthesis infections, the ID specialists should have detailed knowledge of these problems. Usage of antibiotics without ID consultation was prevalent, therefore a continuous educational program is a necessity for healthcare workers in the hospital.     

老年人下呼吸道嗜麦芽窄食单胞菌感染的临床分析

目的 探讨老年人下呼吸道嗜麦芽窄食单胞菌感染的危险因素及该菌对常用抗生素的敏感性。方法 分析40例老年下呼吸道嗜麦芽窄食单胞菌感染患者的临床资料，用K-B法测定该菌的体外药物敏感性。结果 全部患者均有基础疾病，其中慢性阻塞性肺疾病(COPD)20例(50．0％)，混合感染17例(42．5％)。均有抗生素应用史，70．0％的患者机体免疫功能低下，30．0％的患者曾有侵袭性治疗，平均住院时间达41．7d。临床症状及X线表现符合下呼吸道感染。药敏试验提示该菌呈现多重耐药，复方磺胺甲噁唑、环丙沙星、左氧氟沙星、阿米卡星、庆大霉素及氧氟沙星为较敏感抗生素。结论 老年下呼吸道嗜麦芽窄食单胞菌感染多发生于患有各种基础疾病、免疫功能低下及长期应用抗菌药物者，细菌耐药现象严重，诊断及治疗应根据病原学检查及药物敏感试验。