Resistência aos antimicrobianos e diversidade genética de variantes fenotípicas de Pseudomonas aeruginosa não sensíveis aos carbapenêmicos recuperadas de pacientes com fibrose cística com infecção pulmonar crônica: uma análise temporal / Antimicrobial resistance and genetic diversity of phenotypic variants of carbapenem non susceptible Pseudomonas aeruginosa recovered from patients with cystic fibrosis with chronic lung infection: a temporal analysis

Pseudomonas aeruginosa, bactéria ubíqua e versátil, pode se comportar como um patógeno oportunista, com ampla capacidade adaptativa, por múltiplos fatores de virulência e resistência. Como agente patogênico nas infecções pulmonares em pacientes com fibrose cística (FC), é motivo de prognóstico ruim, aumento de hospitalizações e altas taxas de morbimortalidade, sendo quase impossível a sua erradicação, ao evoluírem para a cronicidade. Globalmente, é notável o aumento nos índices de amostras não sensíveis aos carbapenêmicos e a múltiplos antimicrobianos, essenciais à terapêutica. Assim, avaliamos temporalmente a susceptibilidade aos antimicrobianos e a presença de amostras hipermutáveis (HPM) em P. aeruginosa de diferentes morfotipos, não sensíveis aos carbapenêmicos (PANSC), obtidas de pacientes FC com infecção pulmonar crônica, acompanhados em dois centros de referência no Rio de Janeiro. De 2007 a 2016, a análise retrospectiva, através dos resultados obtidos no teste de disco-difusão (TDD), permitiu selecionar amostras de PANSC incluídas neste trabalho. Usando os resultados obtidos no TDD, foi definida a susceptibilidade a outros antimicrobianos, bem como os fenótipos de resistência, multi-(MDR), extensivo-(XDR) e pandroga resistentes (PDR). Adicionalmente, determinou-se a concentração inibitória mínima (CIM) para imipenem (IPM), meropenem (MEM), doripenem (DOR) e polimixina (POL). Através de teste fenotípico, foi calculada a frequência de mutação espontânea e as amostras hipermutáveis foram caracterizadas. O sequenciamento de genoma total (SGT) foi realizado em seis amostras de diferentes morfotipos, incluindo uma variante fenotípica rara, a small colony variant (SCV). Essas amostras foram recuperadas em dois episódios de exacerbação do paciente. Foram investigadas a clonalidade, resistência a antimicrobianos e virulência. Das 143 amostras, de 18 pacientes (9 pediátricos e 9 adultos), os resultados do TDD apontaram taxas de não susceptibilidade superiores a 44% para gentamicina, amicacina, tobramicina e ciprofloxacina, e maiores de 30 % para POL. Pela determinação da CIM, quase a totalidade (96%) das amostras foram não sensíveis a IMP, seguidos de 56% para MEM e 44% para DOR. Analisando-se a distribuição dos valores da CIM50 e CIM90 nos dois grupos de pacientes, os valores para IMP foram maiores entre as amostras dos pacientes pediátricos, equivalendo a 32 µg/mL e 64 µg/mL, respectivamente. Cerca de 25%, 37% e 6% eram MDR, XDR e PDR, respectivamente. Aproximadamente 12% eram HPM, e mais da metade destas foram XDR. Após o SGT, as seis amostras, recuperadas do caso clínico foram classificadas em um novo sequence type (ST2744), com a presença de genes de resistência adquiridos blaPAO, blaOXA-50, aph(3')-Iib, fosA, catB7 e crpP, apresentando mutações em genes codificadores de porinas e bombas de efluxo. Entretanto, não foram observados marcadores genéticos clássicos exclusivos para os fenótipos SCV e HPM. Este é o primeiro relato de P. aeruginosa SCV na FC, no Brasil. A vigilância epidemiológica de P. aeruginosa é crucial para a conduta terapêutica, bem como para o sucesso da resposta do paciente e erradicação da infecção pulmonar, justificando o uso de técnicas fenotípicas e moleculares na detecção dos mecanismos de resistência e virulência desse microrganismo na FC.

Pseudomonas aeruginosa, a ubiquitous and versatile bacterium, can behave as an opportunistic pathogen, with strong adaptive capacity, due to multiple virulence and resistance factors. As a pulmonary infection pathogen in patients with cystic fibrosis (CF), it is related with poor prognosis, increased hospitalizations and high rates of morbidity and mortality, and the eradication is almost impossible, especially after chronicity. The increase rates of isolates non-susceptible to carbapenem and multiple antimicrobials, essentials to therapy, have been observed worldwide. Therefore, we assessed the antimicrobial susceptibility and the presence of hypermutability (HPM) in non-susceptible to carbapenem P. aeruginosa (PANSC) isolates from different morphotypes, obtained from CF patients with chronic pulmonary infection, followed at two reference centers in Rio de Janeiro. Using the results obtained by disk-diffusion test (DDT) between 2007 to 2016, we select 143 PANSC and susceptibility to other antimicrobials was defined, as well as the resistance phenotypes, multi- (MDR), extensive- (XDR) and pandrug resistant (PDR). Additionally, the minimum inhibitory concentration (MIC) for imipenem (IPM), meropenem (MEM), doripenem (DOR) and polymyxin (POL) was determined. Hypermutable isolates were characterized by determination of mutation frequency. Whole genome sequencing (WGS) was performed in six morphotypes isolates, including the small colony variant (SCV), a rare variant phenotype. These isolates were recovered in two exacerbation episodes. Clonality, antimicrobial resistance and virulence were investigated. Of the total (143 isolates) isolated from 18 patients (9 pediatric and 9 adults), non-susceptibility rates above than 44% for gentamicin, amikacin, tobramycin and ciprofloxacin, and more than 30% for POL were observed. Almost all (96%) of the isolates were non-susceptible to IPM by MIC determination, followed by 56% for MEM and 44% for DOR. MIC50 (32 µg/mL) and MIC90 (64 µg/mL) rates for IPM were higher among pediatric patient isolates and 25%, 37% and 6% were MDR, XDR and PDR, respectively. 12% of all isolates were classified as HPM and more than half were categorized as XDR. Using WGS, the six isolates recovered from the clinical case, were identified as a new sequence type (ST2744). Acquired resistance genes blaPAO, blaOXA-50, aph (3')-Iib, fosA, catB7 and crpP and mutations in encoding genes for porins and efflux pumps, was annotated. None exclusive classic genetic markers related to SCV and HPM phenotypes were not observed. This is the first Brazilian report of P. aeruginosa SCV in CF. Our results highlight the importance of epidemiological surveillance in P. aeruginosa. The application of phenotypic and molecular techniques to investigate resistance and virulence mechanisms, can contribute to therapeutic success in CF.

Tratamiento antibiótico empírico de elección en pacientes con urosepsis secundaria a litiasis ureteral: reporte de sensibilidad local / Antimicrobial susceptibility of bacteria causing urosepsis

Background: Early inappropriate antibiotic therapy for the management of urosepsis is associated with higher mortality. Therefore, to establish an adequate empirical therapy is crucial. Aim: To determine an optimal antibiotic treatment, adjusted according local bacterial resistance in patients diagnosed with urosepsis secondary to ureteral lithiasis. Material and Methods: Urine cultures and blood cultures from a prospective cohort of patients with ureteral lithiasis admitted for urosepsis in our center between November 2013 and May 2016, were reviewed. Patients who presented two or more criteria of systemic inflammatory response syndrome (SIRS) and positive blood or urine cultures were admitted. Antimicrobial sensitivity patters derived from cultures were analyzed to describe bacterial susceptibility to commonly used antibiotics. Results: Data from 31 patients were analyzed. Seventeen blood cultures (55%) and 29 urine cultures (94%) were positive. The most commonly isolated pathogens were Escherichia coli in 65% of the cultures, followed by Klebsiella pneumoniae, Proteus mirabilis and Enterococcus faecalis. After performing an analysis of sensitivity and resistance for all bacteria in both blood and urine cultures, amikacin showed the highest sensitivity (100%), followed by 2nd and 3rd generation cephalosporins. Conclusions: Amikacin demonstrated higher antibiotic sensitivity in comparison to other antibiotics for empirical management of patients with urosepsis secondary to ureteral lithiasis.

In vitro synergistic effect of ciprofloxacin with aminoglycosides against multidrug resistant-Pseudomonas aeruginosa

Pseudomonas aeruginosa is an increasingly prevalent nosocomial human pathogen. Infections with multidrugresistant [MDR] P. aeruginosa are currently a treatment challenge and requires search for better treatment options. Purpose of study: To determine in vitro synergistic effect of ciprofloxacin in combination with amikacin and gentamicin against MDR P. aeruginosa clinical isolates. Antibiotic resistance pattern of 100 identified clinical isolates of P. aeruginosa was determined against eight antibiotics by disc diffusion method at Microbiology Laboratory, Holy Family Hospital, Rawalpindi. For 30 selected MDR isolates, minimum inhibitory concentrations [MICs] of amikacin and gentamicin were determined separately by agar diffusion method followed by combined activity of ciprofloxacin with amikacin and gentamicin by checkerboard agar dilution technique. Antibiotic resistance pattern of P. aeruginosa isolates was; gentamicin and carbenicillin [94%], amikacin and piperacillin [92%], ceftazidime [90%], colistin [87%], ciprofloxacin [79%] and imipenem [72%]. MICs against 30 selected MDR isolates ranged from 32 to >/= 128 micro g/ml for amikacin, and >/= 128 micro g/ml for gentamicin. Synergistic effect was observed in 12/30[40%] isolates for AK+CIP and in 05/30 [16.7%] for CN+CIP. Ciprofloxacin in combination with amikacin and gentamicin showed synergistic effect and no antagonistic effect against MDR P. aeruginosa

Increasing antibiotic resistance among uropathogens isolated during years 2006-2009: impact on the empirical management

Urinary tract infections (UTI) are one of the most common infections with an increasing resistance to antimicrobial agents. PURPOSE: Empirical initial antibiotic treatment of UTI must rely on susceptible data from local studies. MATERIALS AND METHODS: Retrospective analysis of isolated bacteria from children with UTIs was performed at the university hospital during years 2006-2009. The findings were compared with data collected in a similar study carried out in 2002- 2003. RESULTS: A total of 1439 uropathogens were isolated. Escherichia coli (E.coli) was the leading cause, followed by Enterobacter, and other gram negative bacilli. It was observed resistance of E.coli to ceftriaxone, cefexime, amikacin, gentamycin, and nalidixic acid; Enterobacter to cefexime; and the resistance of gram negative bacilli to gentamicin and cefexime increased significantly. The highest effective antibiotic was Imipenem, ciprofloxacin, and amikacin with 96.7%, 95% and 91% sensitivity rates , respectively, followed by ceftriaxone 77.2%, gentamicin 77%, nitrofurantoin 76.4%, nalidixic acid 74.3% and cefexime with 70%. CONCLUSION: The use of nitrofurantoin or nalidixic acid as initial empirical antibacterial therapy for cystitis seems appropriate. For cases of simple febrile UTI, the use of initial parenteral therapies with amikacin or ceftriaxone followed by an oral third generation cephalosporin also seemed appropriated, and in cases of severely ill patients or complicated UTI, imipenem as monotherapy or, a combination of Ceftriaxone with an aminoglycoside, are recommended.

In vitro evaluation of antimicrobial activity of Kutajghan vati - an Ayurvedic formulation

The present investigation focuses to determine the antimicrobial potential of an Ayurvedic formulation Kutajghan vati. In this study the activity of this formulation was compared with the standard antibiotics like Amikacin and Norfloxacin. Ethanol, methanol and acetone extract of Kutajghan vati demonstrated good antimicrobial activity and thus can form the basis for the development of a novel antibacterial formulation

Further Increases in Carbapenem-, Amikacin-, and Fluoroquinolone-Resistant Isolates of Acinetobacter spp. and P. aeruginosa in Korea: KONSAR Study 2009

PURPOSE: The increasing prevalence of antimicrobial resistant bacteria has become a serious worldwide problem. The aim of this study was to analyze antimicrobial resistance data generated in 2009 by hospitals and commercial laboratories participating in the Korean Nationwide Surveillance of Antimicrobial Resistance program. MATERIALS AND METHODS: Susceptibility data were collected from 24 hospitals and two commercial laboratories. In the analysis, resistance did not include intermediate susceptibility. Duplicate isolates were excluded from the analysis of hospital isolates, but not from the commercial laboratory isolates. RESULTS: Among the hospital isolates, methicillin-resistant Staphylococcus aureus, penicillin G-non-susceptible Streptococcus pneumoniae based on meningitis breakpoint, and ampicillin-resistant Enterococcus faecium remained highly prevalent. The proportion of vancomycin-resistant E. faecium gradually increased to 29%. Ceftazidime-resistant Escherichia coli and Klebsiella pneumoniae increased to 17% and 33%, respectively, and fluoroquinolone-resistant K. pneumoniae, Acinetobacter spp. and Pseudomonas aeruginosa increased to 33%, 67% and 39%, respectively. Amikacin-resistant Acinetobacter spp. increased to 48%. Imipenem-resistant Acinetobacter spp. and P. aeruginosa increased to 51% and 26%, respectively. Higher resistance rates were observed in intensive care unit (ICU) isolates than in non-ICU isolates among the isolates from hospitals. Resistance rates were higher in hospital isolates than in clinic isolates among the isolates from commercial laboratories. CONCLUSION: Among the hospital isolates, ceftazidime-resistant K. pneumoniae and fluoroquinolone-resistant K. pneumoniae, Acinetobacter spp., and P. aeruginosa further increased. The increase in imipenem resistance was slight in P. aeruginosa, but drastic in Acinetobacter spp. The problematic antimicrobial-organism combinations were much more prevalent among ICU isolates.

Aminoglycoside Susceptibility Profiles of Enterobacter cloacae Isolates Harboring the aac(6')-Ib Gene / 대한진단검사의학회지

The aminoglycoside 6'-N-acetyltransferases of type Ib (aac(6')-Ib) gene confers resistance to amikacin, tobramycin, kanamycin, and netilmicin but not gentamicin. However, some isolates harboring this gene show reduced susceptibility to amikacin. The European Committee on Antimicrobial Susceptibility Testing (EUCAST) recommends a revision of the phenotypic description for isolates harboring the aac(6')-Ib gene. In this study, we determined the aminoglycoside susceptibility profiles of 58 AAC(6')-Ib-producing Enterobacter cloacae isolates. On the basis of the CLSI and EUCAST breakpoints, a large proportion (84.5% and 55.2%, respectively) of these 58 isolates were found to be susceptible to amikacin. However, among the isolates that were shown to be anikacin-susceptible according to the CLSI and EUCAST breakpoints, only 30.6% and 18.8% isolates, respectively, could be considered to have intermediate resistance on the basis of the EUCAST expert rules. Further studies should be conducted to determine the aminoglycoside susceptibility profiles of aac(6')-Ib-harboring isolates from various geographic regions and to monitor the therapeutic efficacy of amikacin in infections caused by these isolates.

In vitro activity of gentamicin and amikacin against Salmonella enterica serovar Typhi: a search for a treatment regimen for typhoid fever

The emergence of Salmonella enterica serovar Typhi isolates resistant to ciprofloxacin and 3rd-generation cephalosporins is a concern for physicians in developing countries. This study assessed the in vitro activity of gentamicin and amikacin against 464 S. enterica serovar Typhi isolates obtained from blood of patients clinically suspected of enteric fever who attended the Calcutta School of Tropical Medicine from 1991 to 2003. The isolates were sensitive to gentamicin and amikacin, showing minimum inhibitory concentrations 0.01-4 microg/mL and 0.005-3.5 microg/mL respectively. Both agents showed bactericidal activity at concentrations of 2 microg/mL after incubation for 6 hours. Aminoglycoside antibiotics such as gentamicin and amikacin may thus be introduced as a treatment regimen for typhoid fever

Activity of amikacin, ertapenem, ciprofloxacin and levofloxacin alone and in combination against resistant nosocomial pathogens by time-kill / Actividad letalidad-tiempo de la amicacina, la ertapenema, la ciprofloxacina y la levofloxacina, solas o en combinación, frente a los patógenos nosocomiales

OBJECTIVE: The purpose of this study was to determine the synergistic activity of amikacin/ertapenem, fluoroquinolones (ciprofloxacin and levofloxacin)/ertapenem and amikacin/fluoroquinolones combinations against resistant nosocomial pathogens. METHODS: Time-kill studies were performed over 24 hours using an inoculum of 5 x 106 - 1 x 107 cfu/mL. Antibiotics were tested at the 1 x MIC and 4 x MIC concentrations. RESULTS: At MIC and/or 4 x MIC concentrations, the antibiotic combinations showed additive or synergistic activity against Acinetobacter strains and extended spectrum beta-lactamase producing Klebsiella pneumoniae. In Escherichia coli strains, synergy was seen when amikacin was combined with ertapenem, ciprofloxacin and levofloxacin; ertapenem in combination with fluoroquinolones demonstrated antagonism. In Pseudomonas aeruginosa strains, synergistic effect was exhibited by ertapenem plus amikacin and ertapenem plus fluoroquinolones. The antibiotic combinations showed antagonistic interaction in methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus faecalis. CONCLUSION: The antibiotic combinations showed additive or synergistic activity against many gram-negative pathogens.

OBJETIVO: El propósito del presente estudio fue determinar la actividad sinérgica de la amicacina/ ertapenema/fluoroquinolonas (ciprofloxacina y levofloxacina)/ertapenema y amicacina/y combinaciones de fluoroquinolonas frente a patógenos nosocomiales resistentes. MÉTODOS: Se realizaron estudios de letalidad-tiempo por 24 horas, usando un inóculo de 5 x 106 - 1 x 107 cfu/mL. Se probaron antibióticos en concentraciones de 1xCIM y 4xCIM. RESULTADOS: En concentraciones de CIM y/o 4 x CIM, las combinaciones de antibióticos mostraron actividad aditiva o sinergésica frente a las cepas Acinetobacter y Klebsiella pneumoniae productoras de la beta-lactamasa de espectro extendido. En las cepas de Escherichia coli, se observó sinergia cuando se combinó la amicacina con la ertapenema, la ciprofloxacina y la levofloxacina; la ertapenema en combinación con las fluoroquinolonas demostró antagonismo. En las cepas de Pseudomonas aeruginosa, se puso de manifiesto un efecto sinergésico al sumar la ertapenema con amicacina y la ertapenema con fluoroquinolonas. Las combinaciones antibióticas mostraron interacción antagonística en Staphylococcus aureus resistente a la meticilina y Enterococcus faecalis resistente a la vancomicina. CONCLUSIÓN: Las combinaciones antibióticas mostraron actividad aditiva o sinergésica frente a muchos patógenos gram-negativos.

Microorganisms present in discharging otitis media in a group of patients in Kathmandu.

Discharge from the ear is one of the commonest symptoms of infections of the ear. To study the major strains of bacteria encountered in ear discharges, this study was conducted from July 1999, to June 2001 in the microbiology laboratory of Om Hospital. A total of 115 patients, of 6-35 years of age clinically diagnosed as discharging otitis media were studied. In 60.9% single organism and in 26.08% two organisms were isolated. Results revealed that, Staphylococcus aureus (34.3%), Klebsiella pneumoniae (24.3%), Pseudomons aeruginosa (22.8%), Enterobacter sps (7.1%), Esch coli (4.3%), Citrobacter sps (1.4%), Proteus sps (1.4%), Acinetobacter sps (1.4%) and Pneumococci (1.4%) were the common organisms in the discharge. Candida albicans (2.8%) was the pathogen in two cases. In 27.8% of cases the causative agent was not demonstrated. About sixty percent (65.9%), 64.8% and 56.0% of the isolates were sensitive to amikacin, ciprofloxacin and gentamycin respectively.

Anomalía de Pelger-Huet: reporte de un caso / Pelger-huet anomaly: a case report

La anomalía de Pelger-Huet se observa una limitación de la segmentación nuclear de los granulocitos. La anomalía fue descrita por primera vez por Pelger en 1928, quien consideró que constituía una manifestación de tuberculosis. Huet consideró que la anomalía sería hereditaria y se transmitiría en forma autonómica dominante. Los individuos afectados rara vez presentan neutrófilos o eosinófilos con más de dos lóbulos. En los heterocigotos, el núcleo de los neutrófilos es no segmentado, con forma de pesa o bilobulado. En los homocigotos, la gran mayoría de los neutrófilos presentan núcleos redondos. Esta anomalía afecta aproximadamente a uno de cada 6000 individuos. La migración celular puede estar levemente alterada, pero la función de los granulocitos es normal y los individuos con esta anomalía hereditaria no padecen efectos adversos. Se trata de Rn masculino quien a las pocas horas de vida presenta ictericia neonatal y dificultad respiratoria y hepatoesplenomegalia. Hallazgos paraclínicos incompatibilidad de grupo sanguíneo, reacción leucemoide 98000 globulos blancos, PCR (-), e hiperbilirrubinemia a predominio de la indirecta. Se indica fototerapia, Oxigeno, y antibioticoterapia a base de PNC, Amikacina y vancomicina, Se realiza serología para TORCHS la cual reporta negativa y valoración por hematología la cual reporta anomalía de Pelger-Huet. Se presenta este caso para dar a conocer la existencia de esta anomalía como causa de errores frecuenctes al momento de valorar la hematología en procesos infecciosos y no infecciosos, que reportan reacciones leucemoides. Es importante que tanto el médico tratante como el paciente, esten en conocimiento de esta anomalía sanguínea, para valorar de forma adecuada el hemograma en posteriores oportunidades.

Cirugía electiva colo-rectal sin preparación mecánica: la ruptura de un paradigma en cirugía: Hospital General del Oeste "Dr. José Gregorio Hernández", Hospital Central de Las Fuerzas Armadas "Dr. Carlos Arvelo" Caracas-Venezuela / Elective colo-rectal surgery without mechanical bowell preparation: a paradigm surgery break up: Hospital General del Oeste Dr. José Gregorio Hernández and Hospital Central de Las Fuerzas Armadas Dr. Carlos Arvelo Caracas-Venezuela

Determinar si la cirugía electiva colo-rectal puede realizarse de forma segura sin preparación mecánica preoperatoria del colon. Evaluación en forma prospectiva de 43 pacientes sometidos a cirugía electiva colo-rectal en dos hospitales del área metropolitana de Caracas: Hospital General del Oeste Dr. José Gregorio Hernández y Hospital Central de las Fuerzas Armadas Dr. Carlos Arvelo. Los pacientes fueron divididos en 2 grupos. Grupo A: constituido por aquellos pacientes a los que se les realiza preparación intestinal mecánica anterógrada y retrograda, más antibioticoterapia profiláctica previa a la cirugía electiva, método utilizado de rutina en nuestros centros. Grupo B conformado por los pacientes a los que se les omitirá la preparación mecánica, recibiendo igualmente la antibioticoterapia profiláctica. Se les efectuó seguimiento postoperatorio hasta 30 días después del acto quirúrgico con el fin de establecer la tasa de complicaciones infeccisas en ambos grupos. Las características demográficas y el tipo de procedimiento quirúrgico no presentaron diferencias estadísticamente significativas. El riesgo de complicación en el grupo preparado fue de 2,33 veces mayor (IC-95 por ciento: 0.83-6,63) que en el grupo no preparado. Esta relación no fue estadísticamente significativa (p=0.179). El rol de la preparación mecánica de colon en la cirugía electiva es cuestionable y no se aprecia que brinde beneficios con respecto a los no preparados.

Aeromonas spp em diferentes pontos do fluxograma de beneficiamento do leite tipo A e susceptibilidade a antimicrobianos / Aeromonas spp in the line production of pasteurized type A milk and their antimicrobial susceptibility

Com o objetivo de verificar os possíveis pontos de contaminação e disseminação de bactérias do gênero Aeromonas em diferentes pontos do fluxograma de beneficiamento do leite tipo A, foram analisadas 120 amostras. Foi verificada a presença de Aeromonas spp. em 38 amostras, sendo identificadas as espécies A. sobria (40 por cento), A hydrophila (22 por cento), A. cavie (26 por cento), A. veronii (19 por cento) e A.schubertii (3 por cento). Das 37 amostras de espécies bacterianas avaliadas quanto à susceptibilidade aos antimicrobianos, foi observada múltipla resistência a drogas em 94 por cento das cepas testadas. As maiores sensibilidades foram observadas frente ao cloranfenicol, netilmicina, amicacina e gentamicina (80 por cento). A presença no leite das espécies deste gênero, comumente associadas com gastrenterites e as altas resistências observadas frente a múltiplos princípios ativos, devem ser levadas em consideração, pois podem representar um sério risco para a saúde dos consumidores, na eventual necessidade da instituição de um regime terapêutico em casos de infecção por Aeromonas spp.

Further Increase of Vancomycin-Resistant Enterococcus faecium, Amikacin- and Fluoroquinolone-Resistant Klebsiella pneumoniae, and Imipenem-Resistant Acinetobacter spp. in Korea: 2003 KONSAR Surveillance

Monitoring temporal trends of antimicrobial resistance can provide useful information for the empirical selection of antimicrobial agents to treat infected patients and for the control of nosocomial infections. In this study, we analyzed antimicrobial resistance of clinically relevant bacteria in 2003 at Korean hospitals and at a commercial laboratory. The following organism-antimicrobial agent resistance combinations were very prevalent: oxacillin-resistant Staphylococcus aureus (68%), expanded-spectrum cephalosporin-resistant Klebsiella pneumoniae (25%), and fluoroquinolone-resistant Escherichia coli (33%), Acinetobacter spp. (58%), and Pseudomonas aeruginosa (40%). Moreover, gradual increases in vancomycin-resistant Enterococcus faecium (20%), cefoxitin-resistant E. coli (10%) and K. pneumoniae (23%), and imipenem-resistant P. aeruginosa (20%) and Acinetobacter spp. (13%) were also observed. The resistance rates of Acinetobacter spp. to most antimicrobial agents at hospitals and at the commercial laboratory were similar. Among the Acinetobacter spp. isolated at a tertiary-care hospital, 46.2% were multidrug-resistant to 9-12 of 13 antimicrobial agents, and 18.3% were panresistant. The exclusion of duplicate isolates at a tertiary-care hospital significantly lowered the proportion of oxacillin-resistant S. aureus, vancomycin-resistant E. faecium, and fluoroquinolone-resistant E. coli.

Uso de antibióticos en pacientes sometidos a apendidectomía: Hospital Patrocinio Peñuela Ruíz: enero de 2001 diciembre de 2004 / Use of antibiotics in patients undergoing appendicectomy: Hospital Patrocinio Peñuela Ruíz: january 2001-december 2004

Los antibióticos (ATB) previenen las complicaciones infecciosas post-apendicectomías. Se realizo un estudio descriptivo, retrospectivo de 220 casos de apendicectomías en el Hospital "Dr. Patrocinio Peñuela Ruíz" desde enero 2001 a diciembre 2004, cuyo objetivo fue determinar el tipo de ATB momento de colocación, duración y coincidencia preoperatoria (ATB-pre) y postoperatoria (ATB-post). El ATB-pre fue administrado un 62,73 por ciento; 2 horas antes de cirugía 48,92 por ciento. El 99,55 por ciento recibió ATB-post durante 3,31 días en promedio. La cefazolina fue el ATB-pre (34,78 por ciento) y ATB-post (16,82 por ciento) mas frecuente. En el 36,96 por ciento coincidieron ATB-pre y ATB-post, el 34,05 por ciento aumento y un 28,26 por ciento cambio totalmente el ATB-post.

Resistencia a gentamicina, amikacina y ciprofloxacina en cepas hospitalarias de klebsiella pneumoniae subespecie pneumoniae productoras de beta-lactamasas de espectro extendido / Resistance to gentamicin, amikacin and ciprofloxacin among nosocomial isolates of klebsiella pneumoniae subspecie pneumoniae producing extended spectrum beta-lactamases

BACKGROUND: Klebsiella pneumoniae is a pathogenic bacterium frequently isolated from nosocomial samples, specially the subspecie pneunonlae, with extensive antibiolic resistance profiles, including third generation cepbhalosporiis, aminoglycosides and quinolones. This is specially true for those strains producing extended spectrum beta lactamases (ESBL). AIM: To investigate the susceptibility to gentamicin, amikacin and ciprofloxacin and the presence of some aminogloycoside modifying enzyme (AMEs) among nosocomial strains of K pneumoniae subspecie pneumoniae producing ESBL. MATERIAL AND METHODS: The antibiotic resistant patterns and the level of resistance (minimal inhibitory concentration, MIC) of 100 strains, isoklted from sel ,eal bospitals of dcifferent Chilean cities, were deterl,in,ed. Tbe presence of some aminoglycosides modifying enzyme (AMEs) was investigated by PCR. RESULTS: Sixty five percent of strains were resistant to gentamicin, 47% were resistant to amikacin, and 29% were resistant to ciprofloxacin. The most frequent AMEs genes detected were the aac(6')-Ib gene (6'N-Acetyltransferase type Ib enzyme) in 69% of strains, conferring resistance to amikacin, kanamycin, tobramycin, and nieoniycin, and the gene aac(3)-IIa (3-Acetyltransferase type 3-IIa enzyme), in 36% of strains, conferring resistance to gentamlicin. CONCLUSIONS: Among nosocomial strains of K pneumoniae subspecie pneumoniae isolaterd from Chilean hospitals, there is an association between the production of ESBL and the resistance to others antimicrobial agents, especially aminoglycosides. Nevertheless, 71% of isolates are susceptible to ciprofloxacin.

Susceptibilidad antimicrobiana de cepas de Pseudomonas aeruginosa aisladas en el laboratorio del Hospital Regional Dr. Leonardo Guzmán de Antofagasta, Chile / In vitro antimicrobial susceptibility of Pseudomonas aeruginosa strains isolated at Hospital Dr. Leonardo Guzmán, Antofagasta, Chile

Pseudomonas aeruginosa es un patógeno nosocomial frecuente que presenta elevada resistencia a los antimicrobianos y causa infecciones graves cuando hay alteración de los mecanismos defensivos del paciente. Así, conocer los patrones locales de sensibilidad es importante para la elección del tratamiento antimicrobiano adecuado en cada institución. En este trabajo determinamos la susceptibilidad antimicrobiana de cepas de P. aeruginosa aisladas desde pacientes atendidos en el Hospital Regional de Antofagasta. La mayoría de los pacientes tenía alguna condición predisponente a la infección y 48% tenía una infección grave. Las cepas mostraron mayor resistencia a los antimicrobianos que lo reportado en trabajos nacionales previos. Las cepas fueron altamente resistentes a amikacina (36,8%), ceftazidima (36,8%) y ciprofloxacina (68,4%), moderadamente resistentes a imipenem (26,3%), mientras que eran escasamente resistentes a piperacilina/tazobactam (5,3%) y cefoperazona/sulbactam (15,8%), Este es el primer trabajo, realizado en nuestra región, que estudia la susceptibilidad de P. aeruginosa frente a distintos grupos de antimicrobianos utilizados en clínica.

Pseudomonas aeruginosa is a nosocomial pathogen that often displays a high degree of antibiotic resistance. This pathogen causes also serious infections specially in patients with severe diseases or immunodeficiency. To offer the best treatment in every institution it is necessary to know the local pattern of antimicrobial susceptibility, then we studied the antibiotic susceptibility of P. aeruginosa strains isolated from patients attended in the Regional Hospital of Antofagasta. Most of them had an underlying disease that predisposed them to the infection and 48% had a severe infection. The strains showed higher drug resistance than that reported by other chilean researchers. P. aeruginosa displayed high resistance to amikacin (36,8%), ceftazidime (36,8%) and ciprofloxacin (68,4%) intermediate resistance to imipenem (26,3%), but low resistance to piperacillin/tazobactam (5,3%) and cefoperazone/sulbactam (15,8%). This is the first drug susceptibility study conducted in the Second Region of Chile, where P. aeruginosa was assayed against those antibiotics used in the clinical practice.

Increasing prevalence of antibiotic resistance and multi drug resistance among uropathogens.

A study was conducted to examine the prevalence of antibiotic resistance in the strains of bacteria isolated from patients with suspected urinary tract infection. A total of 348 bacterial isolates were grown from semi quantitative urine culture and were of significant bacteriuria. The antibiotic susceptibility testing was performed on Muller-Hinton agar by disc diffusion method according to the standard criteria of the National Committee for Clinical Laboratory Standards, Antibiotic susceptibility testing revealed a high prevalence of resistance to ampicillin (55.4%) followed by nitrofurantoin (45.4%), gentamicin (45.1%), amikacin (41.4%) and co-trimoxazole (30.5%). E. coli and Klebsiella pneumonia showed 78.8 % and 75.3 % resistance to three or more drugs respectively. Cefotaxime (87.1%) appeared to be the most active antibiotic against the majority of isolates, followed by Norfloxacin (83.3%).

Invitro comparative evaluation of aminoglycosides at a cancer centre.

A comparative study of in vitro activity of amikacin, gentamicin, netilmicin, tobramycin and isepamicin was done. A total of 200 clinical isolates of Gram negative organisms from various clinical sources were tested. E.Coli was the most frequently isolated organism followed by Pseudomonas spp., Klebsiella spp., Proteus spp., Acinetobacter spp. and Enterobacter spp. Of the 5 aminoglycosides tested, isepamicin showed the highest numbers of susceptible isolates followed by amikacin, netilmicin, gentamicin and tobramycin. MIC 90 value of isepamicin was lower as compared to amikacin.