Microbiological activity and clinical efficacy of a colistin and rifampin combination in multidrug-resistant Pseudomonas aeruginosa infections

The aim of the study was to assess the microbiological activity and clinical efficacy of colistin and rifampin combination against multidrug-resistant (MDR) Pseudomonas aeruginosa infections. The antimicrobial activity of the colistin/rifampin combination was evaluated using the checkerboard and time-kill curve methods against different MDR P. aeruginosa strains. The combination of rifampin and colistin resulted fully (1 strain) or partially (5 strains) synergistic for 6/7 strains and minimum inhibitory concentrations (MICs) in combination were reduced to easily obtainable therapeutic levels. The time-kill curves showed that the combination was bactericidal against the strains tested. The clinical efficacy of the combination was tested in four patients with difficult-to treat infections (sepsis or pneumonia) caused by MDR P. aeruginosa. All infections were successfully treated. Our microbiological and clinical observations suggest that the addition of rifampin to colistin may result in a synergistic bactericidal combination that may be useful in patients with infections caused by MDR P. aeruginosa which are difficult to cure.     

In vitro activity of oral cephalosporins against pediatric isolates of Streptococcus pneumoniae non-susceptible to penicillin, amoxicillin or erythromycin

The aim of this study was to evaluate the effects of penicillin, amoxicillin or erythromycin resistance on the in vitro activity of oral cephalosporins against Streptococcus pneumoniae pediatric isolates. A total of 282 pediatric isolates received during 2005 in the Spanish Reference Pneumococcal Laboratory were tested by agar dilution: 104 strains were penicillin-susceptible, 72 intermediate, and 106 resistant. Serotypes 9 and 14 were the most troublesome with <10% susceptibility to oral cephalosporins. Cefditoren exhibited the highest intrinsic activity against penicillin/amoxicillin-resistant pneumococci, with MIC(90s )of 0.5 microg/ml, followed by cefotaxime (2 microg/ml), cefpodoxime (4 microg/ml), cefuroxime (16 microg/ml), and cefaclor/cefixime (>or= 32 microg/ml), with 0% susceptibility to cefaclor, cefuroxime and cefpodoxime. Cefditoren 0.5 microg/ml inhibited 95.3%, 95.5%, and 98.6% of penicillin-, amoxicillin-, and erythromycin-resistant isolates, respectively. Susceptibility to oral cephalosporins shifted from >90% in penicillin-susceptible isolates to approximately 38% for cefuroxime/cefpodoxime and approximately 7% for cefaclor in penicillin-intermediate, and to 0% in resistant isolates. Despite the different in vitro activity of oral cephalosporins, full resistance to penicillin or amoxicillin implied lack of susceptibility to all oral cephalosporins with defined CLSI breakpoints, rendering them inadequate as empirical treatment in countries with a high prevalence of penicillin resistance.     

In-vitro activities of imipenem–colistin,imipenem–tigecycline,and tigecycline–colistin combinations against carbapenem-resistant Enterobacteriaceae*

The aim of the study is to determine in-vitro effects of imipenem–tigecycline, imipenem–colistin and tigecycline–colistin against carbapenem-resistant Enterobacteriaceae (CRE) isolates. A total of 25 CRE isolates were included to the study. The minimum inhibition concentrations of imipenem, colistin-sulphate and tigecycline were determined with broth dilution method. Synergistic effects of imipenem–tigecycline, imipenem–colistin and tigecycline–colistin were investigated by microdilution checkerboard technique. All of the isolates were resistant to imipenem, whereas 25% of the isolates were resistant to colistin and tigecycline. Imipenem–colistin, imipenem–tigecycline and tigecycline–colistin combinations were synergistic against 40% (10/25), 24% (6/25), and 36% (9/25) of the isolates, respectively. Antagonism was observed in 8% (2/25) of the isolates in tigecycline–colistin combination. Tigecycline–colistin was the most effective (70% synergy) combination in Klebsiella spp. strains; whereas imipenem–colistin was the most effective (75% synergy) combination in Escherichia coli strains. Synergistic effect was variable and strain-depended against CRE isolates that have been tested.     

Comparative antimicrobial spectrum and activity of BMS284756 (T-3811; a desfluoroquinolone) tested against an international collection of staphylococci and enterococci, including in vitro test development and intermethod comparisons

The study was initiated to determine the in vitro activity and MIC/disk test comparisons of BMS284756, a new des-fluoro(6)-quinolone, against isolates of staphylococci and enterococci from the SENTRY Antimicrobial Surveillance Program, 2000. Isolates were tested by reference broth microdilution and standardized disk diffusion methods. Against 3,789 strains of gram-positive cocci from the SENTRY Program (2000), the BMS284756 MIC90 and percentage susceptible at < or = 2 and < or = 4 microg/ml were: Staphylococcus aureus (4 microg/ml; 89.3 and 97.1%), coagulase-negative staphylococci (CoNS; 4 microg/ml; 86.1 and 96.0%) and enterococci (> 4 microg/ml; 62.0 and 76.2%). Also tested were selected staphylococci (300 strains) and enterococci (102 strains) by two standardized methods. The activity of BMS284756 was highly correlated with oxacillin resistance among staphylococci. Oxacillin-susceptible staphylococci were all inhibited by BMS284756 at < or = 0.5 microg/ml, whereas oxacillin-resistant strains required inhibitory concentrations of > or = 1 microg/ml. Excellent correlation was observed between the MIC and 5-microg disk zone diameter for staphylococci and enterococci (r=0.91 to 0.93). Among vancomycin-susceptible enterococci, 67% of Enterococcus faecalis, 25% of E. faecium, and 76% of other Enterococcus spp. isolates were inhibited by BMS284756 at < or = 2 microg/ml. All vancomycin-resistant enterococci (VRE; 11 E. faecalis and 15 E. faecium) were inhibited by > or = 2 microg/ml of BMS284756. Among the non-VRE, non-faecium enterococcal isolates (n=64), 62% were inhibited by < or = 0.5 microg/ml. BMS284756 showed excellent activity against oxacillin-susceptible staphylococci and moderate activity against enterococci other than VRE and E. faecium. Acceptable correlations were observed between MIC and disk test results for both tested genus groups.     

In vitro susceptibility of Cryptococcus neoformans serotypes to GM 237354 derivative of the sordarin class

In vitro susceptibility to the sordarin derivative GM 237354 and amphotericin B were tested in a total of 190 Cryptococcus neoformans clinical isolates from different geographical areas of Spain and South American countries. Minimal inhibitory concentrations (MICs) were obtained using the NCCLS reference microbroth dilution method and analysed according the serotypes of Cr. neoformans. The MICs for amphotericin B were lower than 1.0 microg ml(-1) (MIC90% 0.5 microg ml(-1) , MIC50% 0.125 microg ml(-1)) but five isolates showed MICs of 2.0 microg ml(-1) to GM 237354 (MIC90% 1.0 microg ml(-1), MIC50% 0.5 microg ml(-1)). Cryptococcus neoformans var. gattii serotype B, was significantly less susceptible than A and AD serotypes (P = 0.047 and P = 0.022, respectively).     

In vitro activity of panomycocin, a novel exo-beta-1,3-glucanase isolated from Pichia anomala NCYC 434, against dermatophytes

Killer proteins that are produced and secreted into the environment by certain yeast strains are considered as promising antifungal agents. In this study, in vitro activity of Pichia anomala NCYC 434 (K5) killer protein, panomycocin, which is a 49 kDa glycoprotein with an exo-beta-1,3-glucanase activity was tested against 41 isolates of dermatophytes. Minimum inhibitory concentrations (MICs) were determined by a broth microdilution method based on the reference document M38-A of Clinical and Laboratory Standards Institute (CLSI; formerly NCCLS). For panomycocin MIC determinations two end point criteria MIC-2 (prominent growth inhibition) and MIC-0 (complete growth inhibition) were recorded. All the tested isolates (Microsporum spp. and Trichophyton spp.) were found susceptible to panomycocin. The MIC-2 values ranged from 0.25 to 2 microg ml(-1) and MIC-0 values ranged from 1 to 8 microg ml(-1). These results showed that panomycocin is active in vitro against fungal strains that cause superficial infections and highlighted its probable use as a topical antifungal agent.     

Posaconazole susceptibility testing against Candida species: comparison of broth microdilution and E-test methods

Posaconazole (POS) is a newer triazole with activity against yeasts and moulds. POS and fluconazole were tested in vitro against 32 Candida albicans, 30 C. glabrata, 21 C. tropicalis, 29 C. krusei, 28 C. parapsilosis, 50 C. inconspicua, 13 C. kefyr and 5 C. famata isolates using CLSI broth microdilution method (BMD). We compared E-test and a modified BMD using polyethylene-glycol (PEG) as solvent to the CLSI method. BMDs and E-test were performed according to CLSI and the manufacturer's instructions respectively. Geometric means of POS MICs using BMD were 0.71, 0.22 and 0.21 microg ml(-1) against C. glabrata, C. krusei and C. inconspicua, respectively, and remained below 0.1 microg ml(-1) against all other species tested. One of two C. albicans and two of three C. glabrata isolates resistant to fluconazole showed MICs above 8 microg ml(-1) to POS. The impact of using PEG instead of DMSO had only a minor effect (agreements above 95% with the exception of C. parapsilosis). E-tests read after 24 h showed good agreement with the BMD. POS exhibited excellent in vitro activity against Hungarian Candida strains. E-test showed good correlation with the CLSI method, but to facilitate the comparability of results we believe that DMSO should be used as solvent in the BMD.     

Emergence of tigecycline and colistin resistance in Acinetobacter species isolated from patients in Kuwait hospitals

The development of resistance is a compelling reason for reviewing administration of antibiotics. Recently, most Acinetobacter infections are caused by multidrug-resistant (MDR) strains which have necessitated the use of tigecycline or colistin. This study was undertaken to determine the susceptibility of Acinetobacter spp. to these and other drugs. A total of 250 Acinetobacter isolates were collected from the 8 government hospitals over a period of 6 months. Susceptibility to 18 antibiotics, including tigecycline and colistin, was investigated by determining their minimum inhibitory concentrations using E test. Of the 250 isolates, 13.6% and 12% were resistant to tigecycline and colistin. A total of 25.2% and 37.2% were resistant to imipenem and meropenem, respectively. Of the 250 isolates 88.4% were MDR. This relatively high prevalence of tigecycline and colistin-resistant isolates indicates an emerging therapeutic problem which may severely compromise the treatment of MDR Acinetobacter spp. infections in Kuwait.     

Bacterial isolates from severe infections and their antibiotic susceptibility patterns in Italy: a nationwide study in the hospital setting

The most frequent agents of severe bacterial infections and their antibiotic susceptibility patterns were determined in patients admitted to 45 Italian hospitals over the years 2002-2003. The most common diagnoses were: sepsis (33.8%), pneumonia (9.4%), intravascular catheter-associated infections (9.3%) and ventilator-associated pneumonia (8.1%). Overall, 5115 bacterial isolates were identified from 4228 patients. Three bacterial species, Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli, accounted for more than 50% of the isolates. Other prevalent bacterial isolates were Staphylococcus epidermidis and Enterococcus faecalis, while Acinetobacter baumanii ranked third among all Intensive Care Unit (ICU) isolates. 7% of S. aureus had intermediate resistance to vancomycin. Although E. faecalis displayed no vancomycin resistance, 34% of vancomycin-resistant isolates were found among Enterococcus faecium, one of the highest rates found to date, emphasizing the difference between these two enterococcal species. All the Gram-positive pathogens were susceptible to linezolid, with the exception of approximately 2% of the enterococcal isolates that were intermediate with a minimum inhibitory concentration (MIC)=4 microg/ml. Almost 10% of Escherichia coli, 14% of Klebsiella pneumoniae, 22% of Serratia marcescens and 50% of Enterobacter cloacae were non-susceptible to cefotaxime. Amikacin was the most active antibiotic against P. aeruginosa that showed lack of susceptibility to ceftazidime, gentamicin, piperacillin and ciprofloxacin ranging from 20 to 35%. Finally, Acinetobacter baumanii showed a high level of resistance to all the antibiotics tested including imipenem (58%). The results obtained in this study, the first of its kind in Italy, offer indications for guiding empirical therapy and implementing specific interventions to fight antibiotic-resistant bacterial infections and their transmission in the hospital setting in Italy.     

Comparative in-vitro activities of ertapenem against aerobic bacterial pathogens isolated from patients with complicated intra-abdominal infections

The in vitro activities of ertapenem, ceftriaxone, amoxicillin-clavulanate, ampicillin-sulbactam, and piperacillin-tazobactam were compared against 1018 aerobic bacterial pathogens isolated from 531 patients with complicated intra-abdominal infection. Enterobacteriaceae accounted for 66.3% of the aerobic bacteria; Escherichia coli was the most common isolate. The ertapenem minimal inhibitory concentration was < or = 2 microg/mL for 74.6% of isolates and > or = 8 microg/mL for 21.9% (including isolates of enterococci, methicillin-resistant Staphylococcus aureus, Acinetobacter baumannii, and Pseudomonas aeruginosa). Against Enterobacteriaceae, ertapenem was the most potent and the most active drug evaluated (100% susceptible), followed by ceftriaxone (98% susceptible), piperacillin-tazobactam (96% susceptible), amoxicillin-clavulanate (80% susceptible), and ampicillin-sulbactam (64% susceptible). Piperacillin-tazobactam was the only drug evaluated with clinically useful activity against P. aeruginosa. In summary, ertapenem was highly active in vitro against many clinically important aerobic intra-abdominal bacterial pathogens, especially Enterobacteriaceae.     

Susceptibility testing of Malassezia pachydermatis using the urea broth microdilution method

The in vitro susceptibility of 24 isolates of Malassezia pachydermatis to four antifungal drugs in combination with lysozyme was determined using a urea broth microdilution method. The antifungal activities of each drug alone against 24 isolates of M. pachydermatis were determined as the mean minimal inhibitory concentrations (MICs). MICs of bifonazole, itraconazole, amorolfine and terbinafine were 3.2 microg ml(-1), 1.6 microg ml(-1), 25 microg ml(-1) and 3.2 microg ml(-1), respectively. Lysozyme alone inhibited the growth of M. pachydermatis in a dose-dependent manner, although the lysozyme was unable to kill the cells of M. pachydermatis at the highest concentration of 20 microg ml(-1). Furthermore, the mean MICs of bifonazole, itraconazole, amorolfine and terbinafine in combination with lysozyme were the same as the results for each drug alone. Although the activity of antifungal drugs in combination with lysozyme is enhanced for other fungi. These results suggested that M. pachydermatis might not be affected by the host's natural defences.     

Pseudomonas aeruginosa epidemic strain carrying bla(SPM) metallo-beta-lactamase detected in Rio de Janeiro, Brazil

The present study was designed to characterize beta-lactamase genes and evaluate polymerase chain reaction (PCR) typing for multidrug-resistant Pseudomonas aeruginosa pulsed-field gel electrophoresis (PFGE) genotype A isolates from Rio de Janeiro, Brazil, collected between April 1999 and March 2000 and one additional isolate collected in June 2002. As reported previously, all of the genotype A isolates produced non-characterized metallo-beta-lactamase. These isolates (22) were screened for the bla(SPM) gene by PCR and dot-blotting. Isolates were typed by PCR fingerprinting with primers RAPD-1, 272, 208, 1290, ERIC-1 and ERIC-2. The bla(SPM) gene was detected in 18 (82%) of the 22 isolates. PCR fingerprinting gave results that correlated with PFGE, except with primer 1290. In Rio de Janeiro and other Brazilian states, nearly all SPM-producing P. aeruginosa isolates belong to a single PFGE type accounting for a large proportion of drug-resistant P. aeruginosa hospital infections. RAPD PCR fingerprinting may be a useful technique to screen for an epidemic multidrug-resistant strain in Brazil.     

In vitro susceptibilities of Malaysian clinical isolates of Cryptococcus neoformans var. grubii and Cryptococcus gattii to five antifungal drugs

The in vitro susceptibilities of Malaysian clinical isolates of Cryptococcus neoformans var. grubii and C . gattii to five antifungal drugs (amphotericin B, flucytosine, fluconazole, itraconazole and ketoconazole) were determined using the Etest method. None of the Malaysian isolates was resistant to amphotericin B and ketoconazole. Isolates resistant to flucytosine, fluconazole and itraconazole were observed in this study. Minimum inhibition concentrations (MICs) of > or = 32 microg ml(-1) against flucytosine, > or = 64 microg ml(-1) against fluconazole and > or = 1 microg ml(-1) against itraconazole were noted in four (8.3%), two (4.2%) and one (2.1%) isolates respectively. There was no significant difference in the MICs for both Cryptococcus species (P > 0.05), indicating that C. gattii was as susceptible as var. grubii to all the antifungal drugs tested. No significant difference in the MICs for both Cryptococcus species collected from 1980 to 1990 and 2002 to 2004 were observed (P > 0.05).     

Effects of several antifungal drug combinations against clinical and environmental isolates of Cryptococcus neoformans from China

The in vitro interactions of caspofungin (CSP) with terbinafine (TRB) and ravuconazole (RVC) with 5-fluorocytosine (5-FC) were tested against 82 clinical and environmental isolates of Cryptococcus neoformans from China. The interaction of CSP with TRB proved synergistic against those isolates with a CSP MIC < or =2 microg ml-1 (5% of the isolates), additive against 42% of the isolates and indifferent against 53%. The effects of RVC with 5-FC were synergistic, additive or indifferent against 8%, 26% and 67% of the isolates, respectively. No antagonistic effects were found among any of the drugs. The combinations of CSP with TRB and RVC with 5-FC may display beneficial effects in a strain-dependent manner, while in no case showed antagonistic effects. These data might be of use to design safer and more efficient treatments for patients with cryptococcosis and warrant further evaluation.     

In vitro activity (MIC and MFC) of voriconazole, amphotericin B, and itraconazole against 192 filamentous fungi: the GISIA-2 study

We evaluated the in vitro activity of voriconazole, amphotericin B, and itraconazole against 192 clinical mould isolates recovered in twenty Italian microbiology laboratories. The vast majority of isolates belonged to the genus Aspergillus (94.2%) with A. fumigatus (58.3%) being the most frequently isolated species. Antifungal susceptibility testing was performed using the broth microdilution method defined by the CLSI M38-A standard, and results were compared to those obtained with Sensititre panels. Aspergillus flavus ATCC 204304 was employed as reference strain and results were within all expected ranges. Voriconazole's activity against the 192 mould isolates was comparable to that of amphotericin B and itraconazole: voriconazole MIC90 (CLSI 1 microg/ml, Sensititre 1 microg/ml), itraconazole MIC90 (CLSI 0.5 microg/ml, Sensititre 0.5 microg/ml), amphotericin B MIC90 (CLSI 1 microg/ml, Sensititre 1 microg/ml). In conclusion, these in vitro data highlight voriconazole's broad spectrum activity against filamentous fungi and support its use as a first line agent for the treatment of fungal diseases.     

In vitro evaluation of griseofulvin against clinical isolates of dermatophytes from Isfahan

Fifty dermatophyte isolates, recently obtained from clinical materials, belonging to Trichophyton mentagrophytes, T. verrucosum, Microsporum canis and Epidermophyton floccosum were examined for their susceptibility to griseofulvin. The minimum inhibitory concentration (MIC) values were obtained using the modified microdilution method. All 100% tested isolates had MIC geometric mean at a concentration between 0.43 and 0.95 microg ml(-1) The MIC(90)s and MIC(50)s were 8 microg ml(-1) and <0.25-1 microg ml(-1) respectively. From all isolates, 12% including three T. verrucosum, one M. canis and two T. mentagrophytes isolates had MIC values out of the standardized range, therefore, they were considered as relatively griseofulvin-resistant. At least some of the isolates tested might be difficult to eradicate in clinical terms with griseofulvin treatment in Isfahan.     

Microbiological and epidemiological characterization of imipenem-resistant Pseudomonas aeruginosa strains from a Brazilian tertiary hospital: report from the SENTRY Antimicrobial Surveillance Program

OBJECTIVES: To evaluate the antimicrobial susceptibility profile, the genetic similarity, and the mechanisms of carbapenem resistance among imipenem-resistant Pseudomonas aeruginosa isolates collected from a Brazilian tertiary teaching hospital. METHODS: Seventy-eight consecutive samples of P. aeruginosa were evaluated during 2000 and 2001. The antimicrobial susceptibility was evaluated by reference broth microdilution methods and the imipenem-resistant isolates were screened for metallo-beta-lactamase (MbetaL) production throughout disc approximation test and MbetaL Etest strips and isolates with positive screen test result were submitted to PCR assays using primers blaIMP-1, bla VIM-1, blaVIM-2 e blaSPM-1. The genetic similarity of MbetaL-producing strains was evaluated by automated ribotyping for epidemiological typing purpose. RESULTS: Resistance rates were high to the majority of antimicrobial agents tested except polymyxin B, which inhibited all samples at the Clinical and Laboratory Standards Institute breakpoint (< or = 2 microg/ml). Twenty-nine (37.2%) isolates were resistant to imipenem and these isolates showed great genomic variability. MbetaL production was demonstrated in two imipenem-resistant isolates, which were detected using blaSPM-1 and blaIMP-2-specific primers. Sequence analysis revealed the presence of blaSPM-1 and a novel blaIMP-type gene, blaIMP-16. CONCLUSION: The results of this study showed high resistance rates to the majority of antimicrobial agents among P. aeruginosa samples. High imipenem resistance rates were probably due to continuous selection of resistant mutants. The production of MbetaL did not represent a frequent mechanism of carbapenem resistance in this medical center; but a novel MbetaL was identified. Continued antimicrobial surveillance and infection control measures should be emphasized to minimize the emergence and dissemination of antimicrobial resistance.     

三氧化二砷通过线粒体依赖性通路诱导喉癌细胞株及其耐药株细胞凋亡

背景与目的:三氧化二砷(arsenictrioxide,As2O3)已作为治疗实体瘤的新药应用于临床,但其作用机理仍不清楚。本研究拟探讨As2O3通过线粒体依赖性凋亡通路介导喉癌细胞及其耐药株细胞凋亡的作用。方法:采用MTT法测定As2O3对喉癌细胞KB及其耐药细胞KBv200的细胞毒作用;用AnnexinVFITC染色法检测凋亡早期细胞;细胞线粒体跨膜电位(ΔΨm)用DiOC6标记,流式细胞仪检测。结果:As2O3对KB及KBv200细胞的生长有明显的抑制作用,IC50分别为(0.22±0.02)μg/ml和(0.20±0.01)μg/ml。用AnnexinVFITC染色检测到As2O3呈时间依赖性介导细胞凋亡,2.5μg/mlAs2O3处理24h、48h,KB细胞凋亡率分别为(20.2±3.1)%和(52.2±11.0)%;KBv200细胞凋亡率分别为(15.8±1.3)%和(36.4±5.9)%。2.5μg/mlAs2O3作用于KB与KBv200细胞,ΔΨm降低呈时间依赖性。结论:ΔΨm降低在As2O3诱导喉癌细胞凋亡过程中起着重要的作用。     

Effect of aerosolized colistin on multidrug-resistant Pseudomonas aeruginosa in bronchial secretions of patients without cystic fibrosis

We performed a limited microbiological study to examine the effect of aerosolized colistin (1 million international units every 8 hours) on the colonization of the respiratory tract with Pseudomonas aeruginosa of five intubated, mechanically ventilated patients in the Intensive Care Unit (ICU). No adverse or side effects of the administered aerosolized colistin were reported. The microbial counts of Pseudomonas aeruginosa prior to the use of aerosolized colistin, as well as during the second, fourth, sixth, and eighth day after the use of the drug were measured. The results of this preliminary study suggest that aerosolized colistin was effective in reducing quickly the microbial counts and eliminating microbial growth of Pseudomonas aeruginosa by the sixth day of use in all studied patients.     

Susceptibility to antifungal agents of Candida species isolated from paediatric and adult patients with haematological diseases

Summary The susceptibility to six antifungals: amphotericin B (AMF), 5-fluorocytosine (5-F), miconazole (MIK), ketoconazole (KET), fluconazole (FLU) and itraconazole (ITR) was tested among 206 Candida spp. isolated from paediatric and adult patients with haematological malignancies. To determinate the susceptibility the commercial microdilution method Fungitest (Bio-Rad, France) was used. The strains were classified as susceptible, intermediate susceptible, or resistant on the base of the growth in following breakpoint concentrations of particular drugs: 2 and 8 microg ml(-1) for AMF, 2 and 32 microg ml(-1) for 5-F, 0.5 and 8 microg ml(-1) for MIK, 0.5 and 4 microg ml(-1) for KET and ITR, and 8 and 64 microg ml(-1) for FLU. The highest activity to overall species showed AMF (only one resistant strain) and 5-F (85% susceptible strains). Most of C. albicans isolates were susceptible to tested azoles. The percentages of C. albicans resistant to FLU, ITR, KET and MIK were 4, 11, 8, and 0.8%, respectively. The less susceptible to azoles were C. glabrata and C. krusei (14% and 44% isolates resistant to FLU). A non-albicans Candida isolated from adult patients receiving KET prophylaxis was more frequently resistant to FLU than isolates from patients without previous exposure to azoles (P < 0.05). We did not observe differences in the susceptibility of Candida strains isolated from children compared with those from adults.