Fungal peritonitis in patients undergoing peritoneal dialysis (PD) in Brazil: molecular identification, biofilm production and antifungal susceptibility of the agents.

This paper presents data on fungal peritonitis (FP) in patients undergoing peritoneal dialysis (PD) at the University Hospital of Botucatu Medical School, São Paulo, Brazil. In a total of 422 patients, 30 developed FP, from which the medical records and the fungal isolates of 23 patient cases were studied. All patients presented abdominal pain, cloudy peritoneal effluent, needed hospitalization, had the catheter removed and were treated with fluconazole or fluconazole plus 5-flucitosine; six of them died due to FP. Concerning the agents, it was observed that Candida parapsilosis was the leading species (9/23), followed by Candida albicans (5/23), Candida orthopsilosis (4/23), Candida tropicalis (3/23), Candida guilliermondii (1/23), and Kodamaea ohmeri (1/23). All the isolates were susceptible to amphotericin B, voriconazole and caspofungin whereas C. albicans isolates were susceptible to all antifungals tested. Resistance to fluconazole was observed in three isolates of C. orthopsilosis, and dose-dependent susceptibility to this antifungal was observed in two isolates of C. parapsilosis and in the K. ohmeri isolate. Biofilm production estimates were high or moderate in most isolates, especially in C. albicans species, and low in C. parapsilosis species, with a marked variation among the isolates. This Brazilian study reinforces that FP in PD is caused by a diverse group of yeasts, most prevalently C. parapsilosis sensu stricto species. In addition, they present significant variation in susceptibility to antifungals and biofilm production, thus contributing to the complexity and severity of the clinical features.

Phenotypic and Molecular Characterization of Nonfermenting Gram-Negative Bacilli Causing Peritonitis in Peritoneal Dialysis Patients.

(1) Background: Peritonitis due to nonfermenting Gram-negative bacilli (NF-GNB) is a dramatic complication of peritoneal dialysis (PD) with bad outcomes. Previous studies of PD-related peritonitis due to Pseudomonas species have shown a low-resolution rate, without a high resistance rate to antipseudomonal antibiotics. This suggests that bacterial virulence factors can act and influence peritonitis evolution. This study aimed to describe the microbiological characteristics of NF-GNB causing PD-related peritonitis and analyze their influence on the outcome. (2) Methods: We analyze the 48 isolates from NF-GNB peritonitis, which were stored in our culture collection regarding bacterial resistance, biofilm, and other virulence factors' production, and clonal profile. Additionally, we collected data on treatment and outcomes from patients' clinical registers. (3) Results: The etiologies were species of Pseudomonas (50%), Acinetobacter (36%), and other NF-GNB (14%). There was a high (75%) proportion of biofilm producer lineages. The in vitro susceptibility rate of Pseudomonas spp. to amikacin, ciprofloxacin, and ceftazidime was significantly greater than that of Acinetobacter spp. and other species; however, there was a similar low-resolution rate (<45%) among the episodes attributable to them. Pseudomonas species have a polyclonal profile, while we found a clone of five multiresistant Acinetobacter baumannii over an 8-year interval (2000-2008), which suggest an origin from the healthcare environment. (4) Conclusions: We are not able to identify any predictor of outcome, but it is possible that biofilm and others virulence factors can act in concert and contribute to the bad outcome.

Incidence and characteristics of methicillin-resistant coagulase-negative Staphylococcus aureus in peritoneal dialysis-associated peritonitis in a single center using molecular methods.

PURPOSE: Peritonitis is a serious complication of peritoneal dialysis and coagulase-negative Staphylococcus (CNS) is the most frequent cause of peritoneal dialysis (PD)-infections in many centers. This study aimed to investigate the molecular epidemiology of CNS isolated from PD-peritonitis in a Brazilian single center, focusing on the genetic determinants conferring methicillin resistance. METHODS: Bacterial strains were isolated from peritoneal fluid of patients presenting PD-peritonitis, identified by phenotypic and molecular methods, and those identified as CNS were submitted to mecA detection, SCCmec, pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). RESULTS: Over the 18-year period of this study (1995-2011), a total of 878 peritonitis episodes were diagnosed in this unit, 115 were caused by coagulase-negative staphylococci of which 72 by Staphylococcus epidermidis. mecA gene was detected in 55 CNS (47.8%), more frequently on the more recent years. SCCmec type III was the most frequent cassette, followed by SCCmec type IV and SCCmec type II. A diverstity of pulsotypes was observed among the S. epidermidis isolates, but five clusters (based on the 80% cutoff) were identified. Diversified sequence types (ST02, ST05, ST06, ST09, ST23, ST59 and ST371) were detected. CONCLUSIONS: Detection of SCCmec type III among coagulase-negative Staphylococcus underscores the role of hospital environments as potential source of methicillin-resistant Staphylococcus causing peritonitis in PD patients.

Clinical and microbiological factors predicting outcomes of nonfermenting gram-negative bacilli peritonitis in peritoneal dialysis.

Peritonitis due to gram-negative bacilli (GNB), particularly nonfermenting GNB (NF-GNB), is a serious complication of peritoneal dialysis with a low resolution rate. Beyond the patient's condition, microbiological properties such as antimicrobial resistance, biofilm production and other virulence factors can explain the poor outcomes. This study aimed to evaluate the influence of patient condition, microbiological characteristics, including biofilm production, and treatment on peritonitis outcome. We reviewed the records of 62 index episodes caused by NF-GNB that occurred between 1997 and 2015 in our center. The etiologies were species of Pseudomonas (51.6%), Acinetobacter (32.2%), and other NF-GNB (16.1%). There was a high (72.9%) proportion of biofilm producer lineages. The in vitro susceptibility rate of Pseudomonas spp. to amikacin, ciprofloxacin, and ceftazidime was significantly greater than that of Acinetobacter spp. and other species; however, there was a similar low resolution rate (< 45%) among the episodes attributable to them. Preexisting exit-site infection was independently associated with nonresolution. No other factor, including biofilm production, was associated with the outcome. The higher in vitro susceptibility of Pseudomonas compared to other NF-GNB that presented a similar resolution rate suggests that bacterial virulence factors such as biofilms can act in concert, thereby worsening the outcome.

Genomic and Clinical Characterization of IMP-1-Producing Multidrug-Resistant Acinetobacter bereziniae Isolates from Bloodstream Infections in a Brazilian Tertiary Hospital.

Acinetobacter baumannii is the main species of the Acinetobacter genus; however, non-baumannii Acinetobacter (NBA) species causing infections have been described for the past years, as well as antimicrobial resistance. In this study, we describe the occurrence of two multidrug-resistant (MDR) IMP-1-producing Acinetobacter bereziniae isolates recovered from bloodstream infections in different patients but in the same intensive care unit among 134 carbapenem-resistant Acinetobacter screened. Antimicrobial susceptibility testing revealed resistance to carbapenems, extended spectrum, and antipseudomonad cephalosporins, amikacin, and trimethoprim-sulfamethoxazole. Both A. bereziniae isolates shared the same ApaI-pulsed-field gel electrophoresis (PFGE) pattern. Whole-genome sequencing of both isolates revealed that blaIMP-1 was embedded into an In86 Class I integron carrying also sul1, aac(6')-31, and aadA genes. A new sequence type (ST1309 Pasteur) was deposited. The virulence genes lpxC and ompA, seen in A. baumannii, were detected in the A. bereziniae strains. Recognition of A. bereziniae causing invasive MDR infection underscores the role of NBA species as human pathogens especially in at-risk patients.

Emergence and Persistence of High-Risk Clones Among MDR and XDR A. baumannii at a Brazilian Teaching Hospital.

Dissemination of carbapenem-resistant Acinetobacter baumannii is currently one of the priority themes discussed around the world, including in Brazil, where this pathogen is considered endemic. A total of 107 carbapenem-resistant A. baumannii (CRAB) isolates were collected from patients with bacteraemia attended at a teaching hospital in Brazil from 2008 to 2014. From these samples, 104 (97.2%) carried bla OXA-23-like, all of them associated with ISAba1 The bla OXA-231 (1.9%) and bla OXA-72 (0.9%) genes were also detected in low frequencies. All isolates were susceptible to minocycline, and 38.3% of isolates presented intermediate susceptibility to tigecycline (MIC = 4 µg/ml). Molecular typing assessed by multi-locus sequence typing demonstrated that the strains were mainly associated with clonal complexes CC79 (47.4%), followed by CC1 (16.9%), and CC317 (18.6%), belonging to different pulsotypes and in different prevalences over the years. Changes in the clones' prevalence reinforce the need of identifying and controlling CRAB in hospital settings to preserve the already scarce therapeutic options available.

Peritoneal dialysis-related peritonitis due to coagulase-negative Staphylococcus: a review of 115 cases in a Brazilian center.

BACKGROUND AND OBJECTIVES: Coagulase-negative Staphylococcus (CNS) is the most frequent cause of peritoneal dialysis (PD)-related peritonitis in many centers. This study aimed to describe clinical and microbiologic characteristics of 115 CNS episodes and to determine factors influencing the outcome. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: This study reviewed the records of 115 CNS peritonitis episodes that occurred in 74 patients between 1994 and 2011 at a single university center. Peritonitis incidences were calculated for three consecutive 6-year periods (P1, 1994-1999; P2, 2000-2005; P3, 2006-2011) and annually. The production of biofilms, enzymes, and toxins was evaluated. Oxacillin resistance was evaluated based on its minimum inhibitory concentration and the presence of the mecA gene. RESULTS: The overall incidence of CNS peritonitis was 0.15 episodes per patient per year and did not vary over time (0.12, 0.14, and 0.16 for P1, P2, and P3, respectively; P=0.21). The oxacillin resistance rate was 69.6%. Toxin and enzyme production was infrequent and 36.5% of CNS strains presented the gene encoding biofilm production. The presence of icaAD genes associated with biofilm production was predictive of relapses or repeat episodes (odds ratio [OR], 2.82; 95% confidence interval [95% CI], 1.11 to 7.19; P=0.03). Overall, 70 episodes (60.9%) resolved; oxacillin susceptibility (OR, 4.41; 95% CI, 1.48 to 13.17; P=0.01) and vancomycin use as the first treatment (OR, 22.27; 95% CI, 6.16 to 80.53; P<0.001) were the only independent predictors of resolution. CONCLUSIONS: Oxacillin resistance and vancomycin use as the first treatment strongly influence the resolution rate in CNS peritonitis, which reinforces the validity of the International Society for Peritoneal Dialysis guidelines on monitoring bacterial resistance to define protocols for initial treatment. These results also suggest that the presence of biofilm is a potential cause of repeat peritonitis episodes.

Overlapped sequence types (STs) and serogroups of avian pathogenic (APEC) and human extra-intestinal pathogenic (ExPEC) Escherichia coli isolated in Brazil.

Avian pathogenic Escherichia coli (APEC) strains belong to a category that is associated with colibacillosis, a serious illness in the poultry industry worldwide. Additionally, some APEC groups have recently been described as potential zoonotic agents. In this work, we compared APEC strains with extraintestinal pathogenic E. coli (ExPEC) strains isolated from clinical cases of humans with extra-intestinal diseases such as urinary tract infections (UTI) and bacteremia. PCR results showed that genes usually found in the ColV plasmid (tsh, iucA, iss, and hlyF) were associated with APEC strains while fyuA, irp-2, fepC sitDchrom, fimH, crl, csgA, afa, iha, sat, hlyA, hra, cnf1, kpsMTII, clpVSakai and malX were associated with human ExPEC. Both categories shared nine serogroups (O2, O6, O7, O8, O11, O19, O25, O73 and O153) and seven sequence types (ST10, ST88, ST93, ST117, ST131, ST155, ST359, ST648 and ST1011). Interestingly, ST95, which is associated with the zoonotic potential of APEC and is spread in avian E. coli of North America and Europe, was not detected among 76 APEC strains. When the strains were clustered based on the presence of virulence genes, most ExPEC strains (71.7%) were contained in one cluster while most APEC strains (63.2%) segregated to another. In general, the strains showed distinct genetic and fingerprint patterns, but avian and human strains of ST359, or ST23 clonal complex (CC), presented more than 70% of similarity by PFGE. The results demonstrate that some "zoonotic-related" STs (ST117, ST131, ST10CC, ST23CC) are present in Brazil. Also, the presence of moderate fingerprint similarities between ST359 E. coli of avian and human origin indicates that strains of this ST are candidates for having zoonotic potential.

Outbreak of fungemia caused by Candida parapsilosis in a neonatal intensive care unit: molecular investigation through microsatellite analysis.

BACKGROUND: Opportunistic infections are an increasingly common problem in hospitals, and the yeast Candida parapsilosis has emerged as an important nosocomial pathogen, especially in neonatal intensive care units (NICUs) where it has been responsible for outbreak cases. Risk factors for C. parapsilosis infection in neonates include prematurity, very low birth weight, prolonged hospitalization, indwelling central venous catheters, hyperalimentation, intravenous fatty emulsions and broad spectrum antibiotic therapy. Molecular methods are widely used to elucidate these hospital outbreaks, establishing genetic variations among strains of yeast. AIMS: The aim of this study was to detect an outbreak of C. parapsilosis in an NICU at the "Hospital das Clinicas", Faculty of Medicine of Botucatu, a tertiary hospital located in São Paulo, Brazil, using the molecular genotyping by the microsatellite markers analysis. METHODS: A total of 11 cases of fungemia caused by C. parapsilosis were identified during a period of 43 days in the NICU. To confirm the outbreak all strains were molecularly typed using the technique of microsatellites. RESULTS: Out of the 11 yeast samples studied, nine showed the same genotypic profile using the technique of microsatellites. CONCLUSIONS: Our study shows that the technique of microsatellites can be useful for these purposes. In conclusion, we detected the presence of an outbreak of C. parapsilosis in the NICU of the hospital analyzed, emphasizing the importance of using molecular tools, for the early detection of hospital outbreaks, and for the introduction of effective preventive measures, especially in NICUs.

Detection of SPM and IMP metallo-ß-lactamases in clinical specimens of Pseudomonas aeruginosa from a Brazilian public tertiary hospital.

Phenotypic and genotypic SPM and IMP metallo-ß-lactamases (MBL) detection and also the determination of minimal inhibitory concentrations (MIC) to imipenem, meropenem and ceftazidime were evaluated in 47 multidrug-resistant Pseudomonas aeruginosa isolates from clinical specimens. Polymerase chain reaction detected 14 positive samples to either blaSPM or blaIMP genes, while the best phenotypic assay (ceftazidime substrate and mercaptopropionic acid inhibitor) detected 13 of these samples. Imipenem, meropenem and ceftazidime MICs were higher for MBL positive compared to MBL negative isolates. We describe here the SPM and IMP MBL findings in clinical specimens of P. aeruginosa from the University Hospital of Botucatu Medical School, São Paulo, Brazil, that reinforce local studies showing the high spreading of blaSPM and blaIMP genes among brazilian clinical isolates.

Species distribution and susceptibility profile of Candida species in a Brazilian public tertiary hospital.

BACKGROUND: Species identification and antifungal susceptibility tests were carried out on 212 Candida isolates obtained from bloodstream infections, urinary tract infections and dialysis-associated peritonitis, from cases attended at a Brazilian public tertiary hospital from January 1998 to January 2005. FINDINGS: Candida albicans represented 33% of the isolates, Candida parapsilosis 31.1%, Candida tropicalis 17.9%,Candida glabrata 11.8%, and others species 6.2%. In blood culture, C. parapsilosis was the most frequently encountered species (48%). The resistance levels to the antifungal azoles were relatively low for the several species, except for C. tropicalis and C. glabrata. Amphotericin B resistance was observed in 1 isolate of C. parapsilosis. CONCLUSIONS: The species distribution and antifungal susceptibility herein observed presented several epidemiological features common to other tertiary hospitals in Latin American countries. It also exhibited some peculiarity, such as a very high frequency of C. parapsilosis both in bloodstream infections and dialysis-associated peritonitis. C. albicans also occurred in an important number of case infections, in all evaluated clinical sources. C. glabrata presented a high proportion of resistant isolates. The data emphasize the necessity to carry out the correct species identification accompanied by the susceptibility tests in all tertiary hospitals.

Detection of SPM and IMP metallo-β-lactamases in clinical specimens of Pseudomonas aeruginosa from a Brazilian public tertiary hospital

Phenotypic and genotypic SPM and IMP metallo-β-lactamases (MBL) detection and also the determination of minimal inhibitory concentrations (MIC) to imipenem, meropenem and ceftazidime were evaluated in 47 multidrug-resistant Pseudomonas aeruginosa isolates from clinical specimens. Polymerase chain reaction detected 14 positive samples to either blaSPM or blaIMP genes, while the best phenotypic assay (ceftazidime substrate and mercaptopropionic acid inhibitor) detected 13 of these samples. Imipenem, meropenem and ceftazidime MICs were higher for MBL positive compared to MBL negative isolates. We describe here the SPM and IMP MBL findings in clinical specimens of P. aeruginosa from the University Hospital of Botucatu Medical School, São Paulo, Brazil, that reinforce local studies showing the high spreading of blaSPM and blaIMP genes among brazilian clinical isolates.

Propolis: anti-Staphylococcus aureus activity and synergism with antimicrobial drugs.

Propolis is a natural resinous substance collected by bees from tree exudates and secretions. Its antimicrobial activity has been investigated and inhibitory action on Staphylococcus aureus growth was evaluated. The in vitro synergism between ethanolic extract of propolis (EEP) and antimicrobial drugs by two susceptibility tests (Kirby and Bauer and E-Test) on 25 S. aureus strains was evaluated. Petri dishes with sub-inhibitory concentrations of EEP were incubated with 13 drugs using Kirby and Bauer method and synergism between EEP and five drugs [choramphenicol (CLO), gentamicin (GEN), netilmicin (NET), tetracycline (TET), and vancomycin (VAN)] was observed. Nine drugs were assayed by the E-test method and five of them exhibited a synergism [CLO, GEN, NET, TET, and clindamycin (CLI)]. The results demonstrated the synergism between EEP and antimicrobial drugs, especially those agents that interfere on bacterial protein synthesis.

Propolis: anti-Staphylococcus aureus activity and synergism with antimicrobial drugs

Propolis is a natural resinous substance collected by bees from tree exudates and secretions. Its antimicrobial activity has been investigated and inhibitory action on Staphylococcus aureus growth was evaluated. The in vitro synergism between ethanolic extract of propolis (EEP) and antimicrobial drugs by two susceptibility tests (Kirby and Bauer and E-Test) on 25 S. aureus strains was evaluated. Petri dishes with sub-inhibitory concentrations of EEP were incubated with 13 drugs using Kirby and Bauer method and synergism between EEP and five drugs [choramphenicol (CLO), gentamicin (GEN), netilmicin (NET), tetracycline (TET), and vancomycin (VAN)] was observed. Nine drugs were assayed by the E-test method and five of them exhibited a synergism [CLO, GEN, NET, TET, and clindamycin (CLI)]. The results demonstrated the synergism between EEP and antimicrobial drugs, especially those agents that interfere on bacterial protein synthesis.

Consideraçöes sobre os 10 anos de atividades do Sistema COBA / Considerations about ten years of activities of the COBA system

O sistema COBA (Controle bacteriológico) foi instituído com o propósito fundamental de estabelecer banco de dados na área de Microbiologia Clínica, a nível nacional, por meio de informaçöes sobre a ocorrência de germes patológicos isolados de material clínico na atividade de rotina dos laboratório de análise e a sensibilidade aos antimicrobianos apresentada por estes microrganismos. O presente artigo discorre sobre as atividades do Sistema no período de 10 anos, destacando algumas impropriedades no uso e na execuçäo do antibiograma e/ou identificaçäo bacteriana que foram detectados em trabalho anterior

Sistema COBA 1988 - aspectos relativos aos dados dos laboratórios de referência / COBA 1988 system - aspects relatives of date of reference laboratory

Em 1988 foram processados dados relativos acerca de 31.000 antibiogramas realizados pelos laboratórios que participam do Sistema COBA. Destes, aproximadamente 19.000 tivera origem nos Laboratórios de Referência do Sistema, correspondendo a 61//do total de antibiogramas considerados. Foram analisados os germes mais resistentes às drogas de maior atividade

Atividade comparada da cefepima, cefpiroma e amicacina em amostras bacterianas hospitalares / Comparative study of cefepime, cefpirome and amikacin activities against nosocomial bacteria isolates

O objetivo deste estudo foi avaliar a atividade in vitro da cefepima, da cefpiroma e da amicacina em bactérias hospitalares prevalentes. Inicialmente, procurou-se caracterizar a sensibilidade às três drogas em 1.022 amostras patogênicas isoladas consecutivamente de pacientes internados no Hospital da Clínicas da Faculdade de Medicina de Botucatu, SP, de março a dezembro de 1996, utilizando-se o método da difusäo proposto por Bauer-Kirby. Os resultados expressaram, em geral, elevada atividade das 3 drogas frente a maioria das bactérias, destacando-se que a atuaçäo da cefepima foi significativamente maior que a da cefpiroma e da amicacina (X2, p 0,05) para o total de germes (79,5 por cento x 74,3 por cento x 76,8 porcento) e amostras de Pseudomonas aeruginosa (72 porcento x 56 porcento x 64 porcento) e de Enterobacter cloacae (98 porcento x 88 porcento x 86 porcento, respectivamente). A cefpiroma apresentou maior atividade que a cefepima apenas frente ao Enterococcus faecalis. Nos doze outros grupos bacterianos estudados houve sensibilidade semelhante (X2, p> 0,05) às três drogas. A seguir, determinou-se a concentraçäo inibitória mínima (CIM) pelo E-test para 127 amostras bacterianas, de mesma origem daquelas descritas antes e isoladas em 1997: E.cloacae (12), Citrobacter sp (15), P.aeruginosa (50), acinetobacter baumanni (12), bastonetes Gram-negativos näo-fermentadores (BGNFs) outros (22) e E. faecalis (16). Os resultados expressos pela faixa de variaçäo das CIMs, CIM50 porcento, CIM90 porcento e pela proporçäo de amostras sensíveis, permitiram concluir que a atividade da cefepima contra as bactérias Gram-negativas foi duas vezes maior, ou mais, que a da cefpiroma e da amicacina, especialmente quando a CIM90 porcento foi considerada. Estes dados confirmam os resultados do antibiograma e acrescentam importante informaçäo de natureza quantitativa. Espera-se que estes resultados possam contribuir para o uso racional destas drogas em nosso meio, sobretudo nos pacientes com infecçäo hospitalar. (Au);

Estudo sobre a resistência aos antimicrobianos em bactérias isoladas de pacientes hospitalizados (Botucatu, 1988-1992) / Survey of resistance to antimicrobial drugs in isolated bacterias from hospitalized patients (Botucatu, 1988-1992)

A resistência de bactérias isoladas de pacientes hospitalizados varia segundo o local e a época. Objetivamos neste estudo estabelecer os padrões de sensibilidade a droga antimicrobianas de 1.200 amostras isoladas de material clínico de pacientes hospitalizados sendo 300 de cada espécie prevalente nas infecçöes hospitalares do HC da Faculdade de Medicina de Botucatu, de 1988 a 1992: E. coli, Klebsiella pneumoniae, Pseudomonas aeruginosa e S. aureus. Pesquisamos a CIM das bactérias a 13 drogas antimicrobianas: aztreonam (Az), amicacina (Ap), cafalotina (Cf), cefoxitina (Cx), ceftriaxone (Ct), cefatzidima (Cz), gentamicina (G), pefloxacina (Pf), ciprofloxacina (Ci), imipenem + cilastatina (IM), oxacilina (Ox) e vancomicina (V) - pelo método da diluiçäo da droga (de 0,05 a 256 mcg/ml) em meio de cultura sólido (Mueller-Hinton). Estabelecemos os índices: Cl a cinquenta por cento, Cl a setenta e cinco por cento, Cl a noventa por cento, faixa de variaçäo das CIM e porcentagem de amostras resistentes (critério do NCCLS) para cada espécie e antimicrobiano. Concluímos que foram drogas mais ativas (em termos de Cl noventa por cento): E. coli - Az 0,1), Pf (0,1), Ct (0,05) e Cz (0,25); K. pneumoniae - Az (0,25), Ct (0,25), Cz (0,5) e Pf (2,0): P. aeruginosa - Im (4,0); Az (16); Cz (16); Ci (16); S. aureus - V (1,0, Ci (8,0), Am (128) e Cf (128 mcg/ml). A melhor atividade antibacteriana observada "in vitro" foi relacionada as seguintes drogas: aztreonam (77-100 por cento de amostras sensíveis), pefloxacina (73-99, 7 por cento), ceftazidima (50-99, 7 por cento), ciprofloxacina (80 por cento), imipenem (93 por cento) e vancomicina (100 por cento)