• Stenotrophomonas maltophilia
• Antimicrobial resistance
• Antimicrobial susceptibility
• Pneumonia
• Risk factors

• Mortality
• Risk factors
• Stenotrophomonas maltophilia

• Humans
• Bacteremia/mortality
• Bacteremia/microbiology
• Risk Factors
• Stenotrophomonas maltophilia/isolation & purification
• Stenotrophomonas maltophilia/immunology
• Male
• Female
• Aged
• Middle Aged
• Gram-Negative Bacterial Infections/mortality
• Gram-Negative Bacterial Infections/microbiology
• Aged, 80 and over
• Adult
• Pneumonia, Bacterial/mortality
• Pneumonia, Bacterial/microbiology
• Retrospective Studies
• Young Adult

• Stenotrophomonas maltophilia
• Colonisation
• Health workers
• Multidrug-resistant organisms
• Primary care

• Humans
• Female
• Middle Aged
• Male
• Adult
• Cross-Sectional Studies
• Drug Resistance, Multiple, Bacterial
• Risk Factors
• Primary Health Care
• Health Personnel/statistics & numerical data
• Brazil/epidemiology
• Anti-Bacterial Agents/pharmacology
• Anti-Bacterial Agents/therapeutic use
• Carrier State/microbiology
• Carrier State/epidemiology
• Prevalence
• Stenotrophomonas maltophilia/drug effects
• Stenotrophomonas maltophilia/isolation & purification
• Methicillin-Resistant Staphylococcus aureus/drug effects
• Methicillin-Resistant Staphylococcus aureus/isolation & purification

• 226693/Z/22/Z Wellcome Trust

• Aquatic environments
• Colistin-resistant
• Stenotrophomonas maltophilia
• Virulence

• Stenotrophomonas maltophilia/genetics
• Stenotrophomonas maltophilia/drug effects
• Colistin/pharmacology
• Anti-Bacterial Agents/pharmacology
• Virulence/genetics
• Microbial Sensitivity Tests
• Phylogeny
• Biofilms/drug effects
• Lakes/microbiology
• Animals
• Drug Resistance, Multiple, Bacterial/genetics
• Drug Resistance, Bacterial/genetics

• ICU
• Stenotrophomonas maltophilia
• antimicrobial
• antimicrobial stewardship
• critically ill
• multidrug-resistant bacteria
• sepsis

• Pseudomonas aeruginosa
• Stenotrophomonas maltophilia
• Abdominal surgery
• Gram-negative bacteria
• Mortality
• Surgical intensive care unit

• Humans
• Stenotrophomonas maltophilia
• Gram-Negative Bacterial Infections/mortality
• Male
• Retrospective Studies
• Female
• Middle Aged
• Intensive Care Units
• Aged
• Abdomen/surgery
• Hospital Mortality
• Pseudomonas aeruginosa
• Adult
• Cross Infection/mortality
• Cross Infection/microbiology
• Anti-Bacterial Agents/therapeutic use

• CFRPG8M0011 Chang Gung Memorial Hospital

• Stenotrophomonas maltophilia
• drug-resistance
• intensive care unit
• newborn
• trimethoprim-sulfamethoxazole

• Infant, Newborn
• Humans
• Trimethoprim, Sulfamethoxazole Drug Combination/therapeutic use
• Intensive Care Units, Neonatal
• Stenotrophomonas maltophilia
• Retrospective Studies
• Turkey/epidemiology
• Anti-Bacterial Agents/therapeutic use
• Microbial Sensitivity Tests

• Stenotrophomonas maltophilia
• antibiotic
• biofilm
• chronic infection
• opportunistic
• virulence

• Humans
• Virulence
• Stenotrophomonas maltophilia/genetics
• Gram-Negative Bacterial Infections/microbiology
• Anti-Bacterial Agents/pharmacology
• Anti-Bacterial Agents/therapeutic use
• Virulence Factors

• Indiana University-Purdue University Indianapolis

• Stenotrophomonas maltophilia
• anti-bacterial agents
• intensive care units
• pneumonia
• risk factors

• Xanthomonas
• co-trimoxazole
• levofloxacin
• mortality

• Kasem Pungsriwong Foundation

• Antibiotic therapy
• Bacteremia
• Bloodstream infection
• Intensive care
• Levofloxacin
• Stenotrophomonas maltophilia
• Trimethoprim–sulfamethoxazole

• microbiology
• infection

• Stenotrophomonas maltophilia
• meta-analysis
• respiratory tract infection
• review
• risk factors

We collected data on ventilator‐associated pneumonia (VAP) and hospital‐acquired pneumonia (HAP) induced by Stenotrophomonas maltophilia (SM) and Klebsiella pneumoniae (KP) and compared differences between two bacteria in mortality, duration of ventilator use, length of hospital stay, and risk factors for infection.

This study aimed to evaluate the prognosis and to find risk factors of SM‐HAP/VAP versus KP‐HAP/VAP in the intensive care unit (ICU).

This retrospective cohort study included patients admitted to the ICU between June 2019 and June 2021 and diagnosed with SM‐HAP/VAP or KP‐HAP/VAP. The primary outcome was 28‐day mortality.

Ninety‐two HAP/VAP patients (48 with SM‐HAP/VAP and 44 with KP‐HAP/VAP) were included. The 28‐day mortality was 16.7% (8/48 patients) in SM‐HAP/VAP and 15.9% (7/44 patients) in KP‐HAP/VAP (P = 0.922). After adjustment for potential confounders, the hazard ratios for 28‐day mortality in SM‐HAP/VAP were 1.3 (95% CI:0.5–3.7), 1.0 (95% CI:0.4–3.0), 1.4 (95% CI:0.5–4.0), and 1.1 (95% CI:0.4–3.4), respectively.

SM‐HAP/VAP and KP‐HAP/VAP patients in ICU might have a similar prognosis in mortality, the total duration of the artificial airway and ventilator use, the total length of ICU stay, and hospital stay. The risk factors of SM‐HAP/VAP versus KP‐HAP/VAP might be the artificial airway, ventilator use, gastric tube placement, acid suppressant and antibiotics (especially carbapenem).

Stenotrophomonas maltophilia is a widely distributed, Gram-negative bacillus that is increasingly identified as a multidrug-resistant opportunistic pathogen of concern. Here, we report the draft genome sequences of nine strains that were isolated from a freshwater catchment area in Hong Kong, corresponding to four different monophyletic lineages within the species.

• Antibiotic resistance
• Stenotrophomonas maltophilia
• antimicrobial
• biofilm
• virulence factors
• β-lactams

Background and Aims:Stenotrophomonas maltophilia is increasingly found in critically ill patients, but it is considered a pathogen of limited pathogenicity and therefore it is not often targeted. We systematically evaluated risk factors for S. maltophilia pneumonia in ICU patients for better clinical management.

Methods: Prospective and retrospective studies of S. maltophilia infection in the ICU from database establishment to August 8, 2021, were searched through PubMed, web of science, Cochrane Library Embase and CNKI. The literature was independently screened and extracted by two authors according to inclusion and exclusion criteria, evaluated for quality by the NOS scale, and meta-analyzed by stata 14.0 software.

Results: A total of eight studies with a sample size of 2,320 cases were included. Meta-analysis showed that APACHE-II score > 20 (OR = 10.98, 95% CI: 5.67 ~ 21.26), COPD (OR = 3.97, 95% CI: 2.39 ~ 6.61), malignant tumor (OR = 2.15, 95% CI: 1.03 ~ 4.50), mechanical ventilation (OR = 8.75, 95% CI: 2.59 ~ 29.58), tracheotomy (OR = 6.12, 95% CI: 2.06 ~ 18.18), endotracheal intubation (OR = 4.25, 95% CI: 2.30 ~ 7.84), β- Lactamase inhibitors (OR = 9.98, 95% CI: 1.51 ~ 65.96), aminoglycosides (OR = 4.01, 95% CI: 2.06 ~ 7.80), carbapenems (OR = 2.82, 95% CI: 1.49 ~ 5.31), and quinolones (OR = 2.17, 95% CI: 1.21 ~ 3.89) were risk factors for ICU-acquired S. maltophilia pneumonia.

Conclusion: Many risk factors are associated with S. maltophilia pneumonia in ICU patients. Clinical workers should pay more attention to assessing the risk of infection in ICU patients and enhance the prevention and management of high-risk groups, which will help reduce their risk of S. maltophilia infection.

• ICU-acquired pneumonia
• Stenotrophomonas maltophilia
• infection
• meta-analysis
• risk factor

Stenotrophomonas maltophilia is a multidrug resistant pathogen associated with high mortality and morbidity in patients having compromised immunity. The efflux systems of S. maltophilia include SmeABC and SmeDEF proteins, which assist in acquisition of multiple-drug-resistance. In this study, proteome based mapping was utilized to find out the potential drug targets for S. maltophilia strain k279a. Various tools of computational biology were applied to remove the human-specific homologous and pathogen-specific paralogous sequences from the bacterial proteome. The CD-HIT analysis selected 4315 proteins from total proteome count of 4365 proteins. Geptop identified 407 essential proteins, while the BlastP revealed approximately 85 non-homologous proteins in the human genome. Moreover, metabolic pathway and subcellular location analysis were performed for essential bacterial genes, to describe their role in various cellular processes. Only two essential proteins (Acyl-[acyl-carrier-protein]—UDP-N acetyl glucosamine O-acyltransferase and D-alanine-D-alanine ligase) as candidate for potent targets were found in proteome of the pathogen, in order to design new drugs. An online tool, Swiss model was employed to model the 3D structures of both target proteins. A library of 5000 phytochemicals was docked against those proteins through the molecular operating environment (MOE). That resulted in to eight inhibitors for both proteins i.e. enterodiol, aloin, ononin and rhinacanthinF for the Acyl-[acyl-carrier-protein]—UDP-N acetyl glucosamine O-acyltransferase, and rhazin, alkannin beta, aloesin and ancistrocladine for the D-alanine-D-alanine ligase. Finally the ADMET was done through ADMETsar. This study supported the development of natural as well as cost-effective drugs against S. maltophilia. These inhibitors displayed the effective binding interactions and safe drug profiles. However, further in vivo and in vitro validation experiment might be performed to check their drug effectiveness, biocompatibility and their role as effective inhibitors.

• Anti-Bacterial Agents/pharmacology
• Bacterial Proteins/analysis
• Bacterial Proteins/antagonists & inhibitors
• Bacterial Proteins/chemistry
• Drug Delivery Systems
• Models, Molecular
• Molecular Docking Simulation
• Protein Conformation
• Proteome
• Stenotrophomonas maltophilia/drug effects
• Subtractive Hybridization Techniques

• Antibiotic therapy
• Outcome
• Stenotrophomonas maltophilia
• Ventilator-associated pneumonia

Background: The dreaded bacterial infection by extended-spectrum β-lactamases (ESBL)-producers has always troubled the medical field whether on the public, scientific, or clinical levels. One of the lesser known β-lactamases, which is capable of hydrolyzing broad and extended-spectrum cephalosporins—i.e., cephamycins plus oxyimino-β-lactams—are the AmpC β-lactamases. This group, which has also been termed occasionally—and incorrectly—as ESBL Class C, confers resistance to β-lactamase inhibitors. The prevalence of plasmidic AmpC (pAmpC) strains is possibly still a matter of debate considering the unevenly matched data between phenotypically-detected and molecularly-detected pAmpC.

Aim: In the absence of any study in Lebanon addressing the AmpC, our intention was to determine the numbers and percentages of AmpC Enterobacteriaceae isolates, notably plasmid-mediated ones, across different wards at the Centre Hospitalier du Nord (CHN), Lebanon, and highlight the importance of infection control protocols.

Materials and Methods: Carriage and infection with pAmpC Enterobacteriaceae were retrospectively investigated between 2011 and 2015 and prospectively between 2016 and 2019 at the Centre Hospitalier du Nord Hospital, North Lebanon. The rise or decline in the numbers of such strains, in concordance with the allegedly intensive isolation of the patients, were analyzed.

Results: Intensive care unit (ICU) data shows an initial rise in infection isolates from 2012 to 2014 and in the carriage isolates from 2012 to 2013 with later notable overall decrease in the both isolates' numbers with the application of the isolation protocols at CHN from 2014 onwards. Floors 2, 3, and 4 seemed to house the bulk of the isolates as well.

Conclusion: Preventive measures, such as on-going surveillance of the hospital wards by specialized healthcare personnel and strict implementation of infection control practices, should be a top priority in any medical center in order to isolate such strains and try to put a limit for the development and the dissemination of any possible multidrug resistant strains.

• AmpC
• ESBL
• Enterobacteriaceae
• Lebanon
• extended-spectrum β-lactamase
• infectious disease
• isolation protocol
• plasmid

Stenotrophomonas maltophilia is an emerging Gram-negative MDR bacteria. In patients with chronic obstructive pulmonary disease (COPD), it is mostly found in those with severe exacerbation of COPD requiring mechanical ventilation. The significance of S. maltophilia when detected in the sputum of ambulatory patients with COPD is uncertain.

To access the prevalence and the risk factors of the presence of S. maltophilia in the sputum of ambulatory patients with COPD and to determine whether it was associated with prognosis.

All consecutive unselected ambulatory patients with GOLD 2–4 COPD were recruited between January 2017 and September 2019 from the COPD clinic of a tertiary care hospital. Presence of S. maltophilia was defined by a positive sputum culture for S. maltophilia. Demographics, COPD characteristics, comorbidities and known predisposing risk factors associated with S. maltophilia were collected from medical records.

S. maltophilia was detected in the sputum of 41/393 (10%) of study participants. Comorbidities, exacerbation, use of oral steroids and carbapenems in the previous year were risk factors for the presence of S. maltophilia. After adjusting on confounding factors associated with mortality including age, Charlson comorbidity index and FEV₁, S. maltophilia was significantly associated with mortality (adjusted hazard ratio 2.3; 95% CI 1.1–4.9).

In the current study, we found that 10% of ambulatory patients with GOLD 2–4 COPD had S. maltophilia detected in their sputum. In addition, S. maltophilia may represent a marker of overall morbidity in patients with COPD.

• Stenotrophomonas maltophilia
• chronic obstructive
• prognosis
• pulmonary disease
• risk factors

• bacteremia
• colonization
• meropenem
• pneumonia
• risk factors

Stenotrophomonas maltophilia (S. maltophilia) is a rare cause of neonatal sepsis with significant morbidity and mortality and has extensive resistance to several antibiotics leaving few options for antimicrobial therapy. Only a few cases have been reported in neonates from developing countries. We report three cases of critically ill, extramural babies with neonatal S. maltophilia sepsis. All three babies recovered and were discharged.

All three cases were term extramural babies, who were critically ill at the time of presentation at our neonatal intensive care unit. They had features of multiorgan dysfunction at admission. Blood culture was positive for S. maltophilia in two babies and one had a positive tracheal aspirate culture. The babies were treated according to the antibiogram available. They recovered and were subsequently discharged.

Although various authors have reported S. maltophilia in pediatric and adult populations, only a few cases have been reported in the newborn period and this infection is even rarer in developing countries. Although S. maltophilia infection has a grave outcome, our three babies were successfully treated and subsequently discharged.

• Ceftriaxone
• Multidrug resistant
• Neonatal sepsis
• Stenotrophomonas maltophilia
• Cotrimoxazole
• Tigecycline

• acute kidney injury
• covid-19
• stenotrophomonas maltophilia
• trimethoprim-sulfamethoxazole combination
• kidney transplantation

• Acute Kidney Injury/chemically induced
• Anti-Bacterial Agents/administration & dosage
• Anti-Bacterial Agents/adverse effects
• Betacoronavirus
• COVID-19
• Clinical Deterioration
• Coinfection
• Coronavirus Infections/complications
• Coronavirus Infections/drug therapy
• Fatal Outcome
• Gram-Negative Bacterial Infections/complications
• Humans
• Immunocompromised Host
• Kidney Transplantation
• Male
• Middle Aged
• Pandemics
• Pneumonia, Bacterial/drug therapy
• Pneumonia, Bacterial/microbiology
• Pneumonia, Viral/complications
• Pneumonia, Viral/drug therapy
• SARS-CoV-2
• Stenotrophomonas maltophilia
• Transplant Recipients
• Trimethoprim, Sulfamethoxazole Drug Combination/administration & dosage
• Trimethoprim, Sulfamethoxazole Drug Combination/adverse effects

• Stenotrophomonas maltophilia
• antibiotic-induced persistence
• cross-persistence
• daptomycin
• tolerance

• Antimicrobial
• pseudomonal infection
• susceptibility test
• ß-lactamases (ESBLs)

Objectives: To determine the impact of chronic obstructive pulmonary disease (COPD) on incidence, microbiology, and outcomes of ventilator-associated lower respiratory tract infections (VA-LRTI). Methods: Planned ancillary analysis of TAVeM study, including 2960 consecutive adult patients who received invasive mechanical ventilation (MV) > 48 h. COPD patients (n = 494) were compared to non-COPD patients (n = 2466). The diagnosis of ventilator-associated tracheobronchitis (VAT) and ventilator-associated pneumonia (VAP) was based on clinical, radiological and quantitative microbiological criteria. Results: No significant difference was found in VAP (12% versus 13%, p = 0.931), or VAT incidence (13% versus 10%, p = 0.093) between COPD and non-COPD patients. Among patients with VA-LRTI, Escherichia coli and Stenotrophomonas maltophilia were significantly more frequent in COPD patients as compared with non-COPD patients. However, COPD had no significant impact on multidrug-resistant bacteria incidence. Appropriate antibiotic treatment was not significantly associated with progression from VAT to VAP among COPD patients who developed VAT, unlike non-COPD patients. Among COPD patients, patients who developed VAT or VAP had significantly longer MV duration (17 days (9–30) or 15 (8–27) versus 7 (4–12), p < 0.001) and intensive care unit (ICU) length of stay (24 (17–39) or 21 (14–40) versus 12 (8–19), p < 0.001) than patients without VA-LRTI. ICU mortality was also higher in COPD patients who developed VAP (44%), but not VAT(38%), as compared to no VA-LRTI (26%, p = 0.006). These worse outcomes associated with VA-LRTI were similar among non-COPD patients. Conclusions: COPD had no significant impact on incidence or outcomes of patients who developed VAP or VAT.

• chronic obstructive pulmonary disease
• intensive care
• lower respiratory tract infections
• mechanical ventilation
• pneumonia
• tracheobronchitis
• ventilator-associated

There is little descriptive data on Stenotrophomonas maltophilia hospital-acquired pneumonia (HAP) in critically ill patients. The optimal modalities of antimicrobial therapy remain to be determined. Our objective was to describe the epidemiology and prognostic factors associated with S. maltophilia pneumonia, focusing on antimicrobial therapy.

This nationwide retrospective study included all patients admitted to 25 French mixed intensive care units between 2012 and 2017 with hospital-acquired S. maltophilia HAP during intensive care unit stay. Primary endpoint was time to in-hospital death. Secondary endpoints included microbiologic effectiveness and antimicrobial therapeutic modalities such as delay to appropriate antimicrobial treatment, mono versus combination therapy, and duration of antimicrobial therapy.

Of the 282 patients included, 84% were intubated at S. maltophilia HAP diagnosis for duration of 11 [5–18] days. The Simplified Acute Physiology Score II was 47 [36–63], and the in-hospital mortality was 49.7%. Underlying chronic pulmonary comorbidities were present in 14.1% of cases. Empirical antimicrobial therapy was considered effective on S. maltophilia according to susceptibility patterns in only 30% of cases. Delay to appropriate antimicrobial treatment had, however, no significant impact on the primary endpoint. Survival analysis did not show any benefit from combination antimicrobial therapy (HR = 1.27, 95%CI [0.88; 1.83], p = 0.20) or prolonged antimicrobial therapy for more than 7 days (HR = 1.06, 95%CI [0.6; 1.86], p = 0.84). No differences were noted in in-hospital death irrespective of an appropriate and timely empiric antimicrobial therapy between mono- versus polymicrobial S. maltophilia HAP (p = 0.273). The duration of ventilation prior to S. maltophilia HAP diagnosis and ICU length of stay were shorter in patients with monomicrobial S. maltophilia HAP (p = 0.031 and p = 0.034 respectively).

S. maltophilia HAP occurred in severe, long-stay intensive care patients who mainly required prolonged invasive ventilation. Empirical antimicrobial therapy was barely effective while antimicrobial treatment modalities had no significant impact on hospital survival.

clinicaltrials.gov, NCT03506191

• Antimicrobial therapy
• Combination therapy
• Hospital-acquired pneumonia
• Intensive care
• Stenotrophomonas maltophilia

• GNB
• ICU
• Mortality
• Risk factors
• SM
• VAP

Stenotrophomonas maltophilia is an emerging gram-negative pathogen that was previously labeled as a colonizer. Nowadays, with multiple antibiotic usage along with certain host factors, infections caused by this organism are getting attention. We hereby report two cases of ventilator-associated pneumonia in postoperative infants by Stenotrophomonas maltophilia in a cardiac intensive care unit (ICU).

How to cite this article: Baidya A, Kodan P, Fazal F, Tsering S, Menon RP, Jorwal P, et al. Stenotrophomonas maltophilia: More than Just a Colonizer! Indian J Crit Care Med 2019;23(9):434–436.

• Nosocomial
• Stenotrophomonas maltophilia
• Ventilator-associated pneumonia

• Fluoroquinolone
• Meta-analysis
• Stenotrophomonas maltophilia
• Systematic review
• Trimethoprim-sulfamethoxazole

• Bacteremia
• Pathogens
• Pneumonia
• Respiratory infection
• Respiratory tract

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) offers potential cure to acute myeloid leukemia (AML) patients. However, infections with commensal bacteria are an important cause for non-relapse mortality (NRM). We have previously described the impact of multidrug-resistant organism (MDRO) colonization on the survival of allo-HSCT patients. In the aforementioned publication, according to consensus, we there did not consider the opportunistic gram-negative bacterium Stenotrophomonas maltophilia (S. maltophilia) to be an MDRO. Since rate of S. maltophilia colonization is increasing, and it is not known whether this poses a risk for allo-HSCT patients, we here analyzed here its effect on the previously described and now extended patient cohort. We report on 291 AML patients undergoing allo-HSCT. Twenty of 291 patients (6.9%) were colonized with S. maltophilia. Colonized patients did not differ from non-colonized patients with respect to their age, remission status before allo-HSCT, donor type and HSCT-comorbidity index. S. maltophilia colonized patients had a worse overall survival (OS) from 6 months up to 60 months (85% vs. 88.1% and 24.7% vs. 59.7%; p = 0.007) due to a higher NRM after allo-HSCT (6 months: 15% vs. 4.8% and 60 months: 40.1% vs. 16.2% p = 0.003). The main cause of mortality in colonized patients was infection (46.2% of all deaths) and in non-colonized patients relapse (58.8% of all deaths). 5/20 colonized patients developed an invasive infection with S. maltophilia. The worse OS after allo-HSCT due to higher infection related mortality might implicate the screening of allo-HSCT patients for S. maltophilia and a closer observation of colonized patients as outpatients.

• Bacteremia
• Infection control: risk factor
• Stenotrophomonas maltophilia

• acinetobacter baumannii
• intensive care unit
• multidrug-resistance
• pseudomonas aeruginosa

• Acinetobacter baumannii/drug effects
• Acinetobacter baumannii/enzymology
• Acinetobacter baumannii/isolation & purification
• Anti-Bacterial Agents/therapeutic use
• Bacterial Proteins/genetics
• Bacterial Proteins/isolation & purification
• Drug Resistance, Bacterial/genetics
• Drug Resistance, Multiple/genetics
• Enterobacteriaceae Infections/genetics
• Enterobacteriaceae Infections/microbiology
• Enterobacteriaceae Infections/pathology
• Humans
• Intensive Care Units
• Microbial Sensitivity Tests
• Pseudomonas aeruginosa/drug effects
• Pseudomonas aeruginosa/enzymology
• Pseudomonas aeruginosa/isolation & purification
• beta-Lactamases/genetics
• beta-Lactamases/isolation & purification

The aim of this study was to compare the in vitro susceptibility of Klebsiella pneumoniae, Pseudomonas aeruginosa and Stenotrophomonas maltophilia to three fluoroquinolones. The minimum inhibitory concentrations (MICs) to ciprofloxacin, levofloxacin and moxifloxacin were examined by E-test^® for a total of 40 K. pneumoniae strains, 40 S. maltophilia strains and 40 P. aeruginosa strains. Then, the bactericidal activity of these fluoroquinolones was investigated on five strains of each bacterial species by means of time-kill curves. For K. pneumoniae and P. aeruginosa, the distance of the measured MIC from the clinical break-point is a good indicator of the bactericidal activity for ciprofloxacin and levofloxacin as obtained in our experiments. The lower the MIC, the better the bactericidal activity in term of CFU Log decreases. If MIC of ciprofloxacin and levofloxacin against the considered bacteria are far from clinical breakpoint, these two antibiotics are equivalent. According to our MIC₅₀ and modal MIC, the breakpoints of both ciprofloxacin and levofloxacin seem to be somewhat high and data suggest reducing them. On S. maltophilia, none of the tested antibiotics showed a satisfactory activity.

• Anti-Bacterial Agents/pharmacology
• Ciprofloxacin/pharmacology
• Fluoroquinolones/pharmacology
• Inhibitory Concentration 50
• Klebsiella pneumoniae/drug effects
• Levofloxacin/pharmacology
• Microbial Sensitivity Tests
• Moxifloxacin
• Pseudomonas aeruginosa/drug effects
• Stenotrophomonas maltophilia/drug effects

• ICU
• multidrug resistance
• pseudomonas