Superbacterias en acción: intentos de reacción? / Superbacteria in action: a logical evolution?

Desde 1928, los antibióticos eran las primeras armas contra los microoganismos. En 1998 apareció una bacteria resistente que permitió el incremento de las enfermedades infecciosas. Cuanto más expuesta esté una población bacteriana a un antibiótico, las bacterias que sobrevivan se harán más resistentes, aún para defenderse de futuros antibióticos. Pero su empleo está justificado como método de profilaxis en pacientes médicamente comprometidos. En principio, debe indicarse medicación local para reducir la carga microbiana. El proifesional debe saber cuándo recetar un antibiótico y no olvidar que éste es un coadyuvante del tratamiento, ya que es el propio sistema inmune del paciente el que realiza la curación.

Adaptation and validation of the Inventory of Family Protective Factors for the Portuguese culture / Adaptação e Validação do Instrumento Inventory of Family Protective Factors para a cultura portuguesa / Adaptación y Validación del Instrumento Inventory of Family Protective Factors para la cultura portuguesa

OBJECTIVES: to adapt and validate the Inventory of Family Protective Factors (IFPF) for the Portuguese culture. This instrument assesses protective factors that contribute to family resilience. Studies addressing resilience are embedded within the salutogenic paradigm, i.e. it addresses protective factors of individuals or groups without underestimating risk factors or vulnerability. METHOD: in order to assess the IFPF's linguistic and conceptual equivalence, the instrument was translated, retro-translated and the think-aloud protocol was used. We then verified the instrument's sensitiveness, reliability and validity of results to assess its psychometric characteristics. A factor analysis was performed of the principal components with varimax rotation of the scale's items and Cronbach's alpha coefficient was calculated for each dimension. A total of 85 families with disabled children, selected through simple random sampling, self-administered the instrument. RESULTS: the IFPF presents psychometric characteristics that are appropriate for the Portuguese population (Cronbach's alpha = .90). CONCLUSION: the IFPF was adapted and validated for the Portuguese culture and is an instrument to be used in studies intended to assess protective factors of family resilience. .

OBJETIVOS: adaptar e validar o Inventory of Family Protective Factors para a cultura portuguesa. Esse instrumento avalia os fatores protetores que contribuem para a resiliência familiar. Os estudos sobre resiliência inserem-se no paradigma salutogênico, abordando os fatores protetores dos indivíduos, ou grupos, sem subestimar os fatores de risco ou vulnerabilidade. MÉTODO: para avaliar a equivalência linguística e conceitual do Inventory of Family Protective Factors realizou-se a tradução, retroversão e reflexão falada; para aferir as características psicométricas do instrumento, verificou-se a sensibilidade, confiabilidade e a validade dos resultados. Foi realizada uma análise fatorial de componentes principais com rotação Varimax dos itens da escala e calculou-se o coeficiente alfa de Cronbach para cada dimensão. Através de uma amostragem aleatória simples, aplicou-se esse instrumento a 85 famílias de crianças com necessidades especiais que o autopreencheram. RESULTADOS: o Inventory of Family Protective Factors apresenta características psicométricas adequadas para a população portuguesa (alfa de Cronbach de .90). CONCLUSÃO: o Inventory of Family Protective Factors foi adaptado e validado para a cultura portuguesa. Considera-se que se trata de um instrumento útil para estudos nos quais há a proposta de avaliar os fatores protetores da resiliência familiar. .

OBJETIVOS: adaptar y validar el Inventory of Family Protective Factors (IFPF) para la cultura portuguesa. Este instrumento evalúa los factores protectores que contribuyen para la resiliencia familiar. Los estudios sobre resiliencia se insieren en el paradigma salutogénico, abordando los factores protectores de los individuos o grupos, sin subestimar los factores de riesgo o vulnerabilidad. MÉTODO: para evaluar la equivalencia lingüística y conceptual del IFPF realizamos la traducción, retrotraducción y reflexión hablada; para evaluar las características psicométricas del instrumento verificamos la sensibilidad, confiabilidad y la validez de los resultados. Realizamos un análisis factorial de los componentes principales con rotación varimax de los ítems de la escala y calculamos el coeficiente Alpha de Cronbach para cada dimensión. A través de un muestreo aleatorio simple, aplicamos este instrumento a 85 familias de niños con necesidades especiales que lo autollenaron. RESULTADOS: el IFPF presenta características psicométricas adecuadas para la población portuguesa (alfa de Cronbach de 0,90). CONCLUSIÓN: el IFPF fue adaptado y validado para la cultura portuguesa. Consideramos que se trata de un instrumento útil para estudios que se propongan evaluar los factores protectores de la resiliencia familiar. .

ELISA protocol for rapid screening of potential antitubercular drugs based on antigenic reactivity of mycobacterial ES-31 serine protease - a drug target supported by axenic culture of Mycobacterium tuberculosis H37 Ra strain in the presence of inhibitor.

Background: Mycobacterial ES-31 serine protease has been reported to be a drug target using protease and lipase inhibitors in axenic and macrophage cultures. Simple screening techniques are needed for rapid testing of anti-tubercular drugs. Aim: To demonstrate the usefulness of ELISA protocol based on antigenic reactivity of mycobacterial serine protease by indirect ELISA for detecting anti-tubercular activity. Material and Methods: Indirect ELISA for assessment of antigenic reactivity of mycobacterial ES-31 serine protease was standardized using ES-31Ag and anti-DSS-goat-serum and assessed the inhibition of the antigenic reactivity by isoniazid, an anti-tubercular drug and serine protease inhibitor and orlistat, a lipase inhibitor. Results: Optimal antigenic reactivity of mycobacterial ES-31 serine protease was observed at 5μg/well of ES-31 antigen and at 1:25 dilution of anti-DSS-goat-serum. Isoniazid showed 42% inhibition of ES-31 serine protease at 0.4μg/well, while orlistat showed inhibition of 60% at 0.5μg/well. Inhibition of Mtb H37Ra bacilli is further confirmed in axenic culture. 35% and 29% inhibition by isoniazid at 0.4μg/well and orlistat at 0.5μg/well were observed respectively on bacterial growth. Conclusion: Simple ELISA protocol based on assay of antigenic reactivity of mycobacterial ES-31 serine protease, a drug target, has been standardized for rapid screening of potential anti-tubercular drugs.

Capacidad de los laboratorios nacionales de referencia en Latinoamérica para detectar mecanismos de resistencia emergentes / Capability of national reference laboratories in Latin America to detect emerging resistance mechanisms

Objetivo. Evaluar la capacidad de 17 laboratorios nacionales de referencia que participan en el Programa Latinoamericano de Control de Calidad en Bacteriología y Resistencia a los Antimicrobianos (LA-EQAS) para detectar mecanismos de resistencia emergentes, a saber: resistencia de enterobacterias a carbapenemes por presencia de Klebsiella pneumoniae carbapenemasa (KPC); resistencia de enterobacterias a carbapenemes por presencia de metalobetalactamasas (MBL) tipo IMP, y resistencia intermedia a vancomicina de aislamientos de Staphylococcus aureus (VISA). Métodos. Se enviaron los siguientes tres aislamientos a los 17 laboratorios participantes del LA-EQAS: Klebsiella pneumoniae OPS-161 productor de KPC, Enterobacter cloacae OPS-166 productor de IMP y S. aureus OPS-165 con resistencia intermedia a vancomicina. Se evaluó la interpretación de las pruebas de sensibilidad y detección del mecanismo de resistencia y el tamaño de los halos de inhibición (método de difusión por discos) o valor de la concentración inhibitoria mínima (CIM). Resultados. La concordancia en la detección de los mecanismos de resistencia fue de 76,4%, 73,3% y 66,7% con respecto a la cepas K. pneumoniae OPS-161, E. cloacae OPS-166 y S. aureus OPS-165, respectivamente. La concordancia entre las zonas de inhibición obtenidas por los laboratorios participantes y los rangos establecidos por el laboratorio coordinador fue aceptable en los tres aislamientos, ya que alcanzó 90,8%, 92,8% y 88,9%, respectivamente, para cada cepa. Conclusiones. La concordancia global en la detección de los mecanismos de resistencia KPC, MBL y VISA fue de 72,1%. Consideramos que los laboratorios nacionales de referencia de América Latina son capaces de reconocer estos mecanismos de resistencia emergentes y se espera que en el futuro la concordancia alcance su nivel máximo.

Objective. To evaluate the capability of 17 national reference laboratories participating in the Latin American Quality Control Program in Bacteriology and Antibiotic Resistance (LA-EQAS) to detect emerging resistance mechanisms— namely: resistance of enterobacteria to carbapenems due to the presence of Klebsiella pneumoniae carbapenemase (KPC) and metallo-beta-lactamase (MBL) type IMP, and intermediate resistance of Staphylococcus aureus isolates to vancomycin (vancomycinintermediate resistant S. aureus—VISA). Methods. The following three isolates were sent to the 17 participating LA-EQAS laboratories: KPC-producing Klebsiella pneumoniae PAHO-161, IMP-producing Enterobacter cloacae PAHO-166, and S. aureus PAHO-165 with intermediate resistance to vancomycin. Performance of each of the following operations was evaluated: interpretation of sensitivity tests, detection of the resistance mechanism, and assessment of either inhibition halo size (disk diffusion method) or minimum inhibitory concentration (MIC). Results. Concordance in the detection of resistance mechanisms was 76.4%, 73.3%, and 66.7% for the K. pneumoniae PAHO-161, E. cloacae PAHO-166, and S. aureus PAHO- 165 strains, respectively. Concordance between the inhibition areas observed by the participating laboratories and the ranges established by the coordinating laboratory was acceptable for all three isolates, at 90.8%, 92.8%, and 88.9%, respectively. Conclusions. Overall concordance in on the detection of KPC, MBL, and VISA resistance mechanisms was 72.1%. We consider the national reference laboratories in Latin America capable of recognizing these emerging resistance mechanisms and expect that maximum levels of concordance will be reached in the future.

Criterios de ensayo, interpretación e informe de las pruebas de sensibilidad a los antibióticos en los bacilos gram negativos no fermentadores de importancia clínica: recomendaciones de la Subcomisión de Antimicrobianos de la Sociedad Argentina de Bacteriología, Micología y Parasitología Clínicas, Asociación Argentina de Microbiología / Antimicrobial susceptibility testing in clinically relevant non-fermenting gram-negative bacilli: recommendations from the Antimicrobial Agents Subcommittee of the Sociedad Argentina de Bacteriología, Micología y Parasitología Clínicas, Asociación Argentina de Microbiología

En este documento se dan a conocer una serie de recomendaciones para el ensayo, la lectura, la interpretación y el informe de las pruebas de sensibilidad a los antimicrobianos para los bacilos gram negativos no fermentadores (BGNNF) que se aíslan en humanos. Se adoptaron como base las recomendaciones internacionales, las de la Subcomisión de Antimicrobianos de la Sociedad Argentina de Bacteriología, Micología y Parasitología Clínicas y las de un grupo de expertos invitados. Se incluye, además, la nomenclatura actualizada de los BGNNF y la descripción de algunas de sus características individuales, de sus resistencias naturales o habituales a los antimicrobianos de uso clínico y de los mecanismos responsables de tales resistencias. También se indican los agentes antimicrobianos que se deberían ensayar frente a las distintas especies, con la especificación de cuáles deberían ser informados, y su ubicación estratégica en las placas de cultivo para poder detectar los mecanismos de resistencia más frecuentes y relevantes. Por último, se detallan los métodos de detección y de confirmación fenotípica de la presencia de b-lactamasas emergentes en Argentina, como las carbapenemasas clases A y B.

This document contains the recommendations for antimicrobial susceptibility testing of the clinically relevant non-fermenting gram-negative bacilli (NFGNB), adopted after conforming those from international committees to the experience of the Antimicrobial Agents Subcommittee members and invited experts. This document includes an update on NFGNB classification and description, as well as some specific descriptions regarding natural or frequent antimicrobial resistance and a brief account of associated resistance mechanisms. These recommendations not only suggest the antimicrobial drugs to be evaluated in each case, but also provide an optimization of the disk diffusion layout and a selection of results to be reported. Finally, this document also includes a summary of the different methodological approaches that may be used for detection and confirmation of emerging b-lactamases, such as class A and B carbapenemases.

Monocationic surfactant induced ultra structural changes in antibiotic resistant Escherichia coli.

Background & objectives: Cetrimide is a monocationic surfactant, commonly used for disinfection of hospital floors, equipments, for cleansing of burns and wounds, hand wash, etc. We evaluated whether antibiotic resistant (AR) Escherichia coli isolates from hospital settings (nosocomial pathogens) show any evidence of significant reduction in their susceptibility to cetrimide. Also the response of AR E. coli (nosocomial pathogens) to the action of cetrimide was assessed by studying the ultra structural changes induced using transmission electron microscopy (TEM). Methods: A total of 165 clinical samples were screened for isolation of E. coli. Eighty two (49.6%) samples were positive for E. coli. Antibiotic susceptibility testing of E. coli isolates was carried out by Kirby Bauer method to isolate AR E. coli. The randomly selected AR E. coli isolate was treated with different concentrations of cetrimide and minimum inhibitory concentration (MIC) of cetrimide was determined by broth micro dilution method. This same isolate was used for performing time kill assay and TEM study. Results: The test E. coli isolate showed resistance to 12 different antibiotics. The MIC of cetrimide against AR E. coli was 312.5 μg/ml. The ultra cellular structural changes in cetrimide treated AR E. coli revealed vacuole formation, disaxilization of nuclear material, loss of cytoplasmic granularity, bleb formation and cell lysis. Conclusion: Ultra structural changes induced by the action of cetrimide revealed cell damaging changes in the AR E. coli to be dose and time dependent. The results showed that antibiotic resistance does not alter any change in susceptibility of E. coli to cetrimide, which was found to be still an effective disinfectant against a nosocomial pathogen E. coli.

Neumonía asociada a la ventilación mecánica (NAVM): factores de riesgo relacionados con la presencia de gérmenes multirresistentes(AU) / Ventilator-associated pneumonia: risk factors associated with the presence of multiresistant organism

La Neumonía Asociada a la Ventilación Mecánica (NAVM) afecta entre 10 por ciento y 65 por ciento de los pacientes, con una mortalidad atribuible que fluctúa entre 24 por ciento y 76 por ciento. Numerosas directrices recomiendan dividir la NAVM en precoz si ocurre dentro de las primeras 96 horas de ingreso a UCI o tardía si es posterior, ya que las tardías suelen ser ocasionadas por patógenos multirresistentes (PMR). Objetivo: Determinar si hay asociación entre la presencia de PMR con la NAVM tardía, uso previo de antibióticos, comorbilidady gravedad al ingreso a la UCI. Métodos: Estudio prospectivo de 12 meses. El diagnóstico de NAVM fue clínico asociado a cultivo cuantitativo en contaje significativo (106 UFC/ml para cultivo cuantitativo de aspirado endotraqueal, 104 UFC/ml para lavado broncoalveolar (LBA) vía broncoscópica). Resultados: Se enrolaron 48 pacientes con NAVM consecutivos, 19 mujeres, la edad promedio fue de 59+/-18,5 años. Los principales gérmenes involucrados fueron St Aureus meticilino resistente (54 por ciento), Acinetobacter sp (33 por ciento) y Pseudomonas aeruginosa (19 por ciento). El aislamiento de PMR no se asoció significativamente a la NAVM tardía (p >0,05), por el contrario el uso previo de antibióticos se relacionó más estrechamente con la presencia de PMR (p <0,0001). Al analizar variables clínicas sólo la escala de Glasgow más baja al ingreso a la UCI se asoció significativamente con la presencia de PMR (10,7+/-3,3 vs14,5+/-0,5, p <0,05). Conclusión: El uso previo de antibióticos se asocia significativamente a la neumonía por PMR independiente del momento en que se diagnostica la NAVM.

Ventilator-associated pneumonia (VAP) is a mechanical ventilation complication that affects about 10 percent to 65 percent of mechanical ventilated patients. The attributable mortality ranged between 24 percent to 76 percent. Most of the guidelines have recommended to classify VAP in early onset if diagnosis is made in the first 96 hours from ICU admission or late onset if the diagnosis is later. Early onset VAP is reported to be due to antibiotic-sensitive pathogens, while late-onset VAP is frequently attributed to antibiotic-resistant pathogens (ARP). The Aim of the study was to correlate the isolate of ARP with late-onset VAP, prior antimicrobial treatment, comorbidity and severity of illnesses. Methods: 12 months prospective study. VAP was define according a presumptive clinical diagnosis plus an isolation of a pathogen in a significant concentration (>106 CFU/ml for quantitative cultures of endotracheal aspirates, >104 CFU/ml for bronchoalveolar lavage from fiberoptic bronchoscopic). Results:We included 48 patients with VAP, 19 women, the average age was 59 +/- 18,5 years. 75 percent (36/48) were late-onset VAP. The organism most frequently isolated was methicillin resistant S. aureus (54 percent), Acinetobacter sp (33 percent), and Pseudomona aeruginosa (19 percent). ARP was not associated with late-onset VAP (p >0,05), by contrast prior antimicrobial treatment was closely associated to isolation of ARP (p<0,001). When analyzed clinical variables only lower Glasgow coma scale at ICU admission was associated with ARP-VAP (10,7+/-3,3 vs 14,5+/-0,5 p <0,05). Conclusion: Prior antimicrobial treatment was closely associated with ARP-VAP regardless of the timing of VAP Diagnosis.

Susceptibilidade"in vitro" a antimicrobianos de estirpes de Vibrio spp isoladas de camarões (Litopenaeus vannamei) e de água de criação destes animais provenientes de uma fazenda de camarões no Ceará - Nota prévia / In vitro antimicrobial susceptibility of Vibrio spp isolated from shrimp (Litopenaeus vannamei) and water from ponds of a shrimp farm in Ceará

Foram feitos ensaios de susceptibilidade a antibióticos em 48 cepas de Vibrio isoladas do cultivo do Litopenaeus vannamei no Ceará. Para os testes de difusão foram utilizados 11 antibióticos. A espécie que apresentou maior percentagem de resistência aos antimicrobianos foi V. cholerae, onde 33,33% das 12 cepas testadas mostraram-se resistentes a sulfazotrim, 25% a ampicilina e 33,33% a ceftriaxona.

Suscetibility assays were performed for 48 Vibrio strains isolated from pond-reared Litopenaeus vannamei in Ceará, Brazil. The diffusion assays tested 11 antibiotics. The most resistant species was V. cholerae: of 12 strains tested, one third was resistant to sulfamethoxazole-trimethoprim, one fourth to ampicillin and one third to ceftriaxone.

Infecciones por Acinetobacter baumannii pan-resistente: consideraciones epidemiológicas y de manejo antimicrobiano actualizado / Acinetobacter baumannii pandrug-resistant: update in epidemiological and antimicrobial managing issues

En las últimas dos décadas Acinetobacter baumannii ha emergido como un patógeno nosocomial de la mayor relevancia mundial. A baumannii puede ser agente causal de infecciones como neumonía, bacteriemia, meningitis, infecciones del tracto urinario y de partes blandas, asociándose a alta mortalidad. Diversas comunicaciones nacionales y extranjeras revelan el aislamiento de cepas resistentes a casi todos los agentes antimicrobianos comercialmente disponibles, por lo que las opciones terapéuticas se han limitado drásticamente. Esto plantea la necesidad de desarrollar nuevos agentes antibacterianos y resucitar ciertos compuestos abandonados, como las polimixinas, para optimizar la terapéutica de este microorganismo con múltiple resistencia. Con el objeto de revisar y evaluar los datos sobre el manejo de infecciones multirresistentes por A baumannii, se realizó una revisión sistemática de la literatura médica que incluyó Medline y Lilacs, identificando y categorizando la relevancia clínica de las fuentes recolectadas a la fecha de esta investigación. Se repasan aspectos epidemiológicos clínicamente relevantes, datos microbiológicos y estudios clínicos realizados con infecciones por A baumannii pan resistente (AB-PDR) o multirresistente (AB-MDR). La respuesta apropiada al manejo de infecciones por AB-PDR es compleja, su erradicación requiere de adherencia a prácticas adecuadas de control de infecciones y del uso prudente de antimicrobianos, además del empleo de antibioterapia eficaz. Potenciales opciones de terapia serían la colistina, asociaciones de betalactámicos con sulbactam y tetraciclinas pero no existen estudios controlados y aleatorios al respecto.

Inactivation of chloramphenicol by Staphylococcus aureus biotype C from humans & animals.

During an investigation, 55 biotype C (bovine and caprine biotype) Staphylococcus aureus isolated from 43 cows suffering from mastitis, and 20 biotype C Staph. aureus strains from the nares and the side of nail-tips of the right thumbs of 20 farm workers (milkers and animal attendants) on six small dairy farms in Assam and Meghalaya were isolated. Three strains from the former and six strains from the latter from among the isolates on two of the farms were found resistant to chloramphenicol, when tested with a routine susceptibility test. Test of the organisms by the agar dilution method indicated that the resistant strains had a minimal inhibitory concentration for chloramphenicol of 32 micrograms/ml or more, while, the chloramphenicol sensitive strains and two reference strains, Staph. aureus ATCC 25923 and Micrococcus luteus ATCC 9341, had < or = 8 micrograms/ml. Two bovine and five human chloramphenicol resistant strains showed positive results when tested by the Gots test. When these strains were tested by a standard method in broth, containing 30 micrograms chloramphenicol per ml, all showed evidence of inactivating chloramphenicol up to a non-detectable level within 36 h. Inactivation of chloramphenicol by Staph. aureus has clinical significance.

Characterization and mapping of an informational suppressor in Aspergillus nidulans

The present work was undertaken to characterize a suppressor gene present in a mutant strain of A. nidulans obtained with NTG (N-Methyl-N'-Nitro-N-Nitrosoguanidine). Analyses of this mutant have shown that this suppressor, designated suO1, induces phenotypic co-reversion of several auxotrophic mutations and makes the strain sensitive to aminoglycoside antibiotics and lower temperatures. suO1 has shown to be on linkage group VIII. The vegetative growth of the mutant strain is very unstable because the suppressor gene induces the production of prototrophic mitotic sectors. The strains bearing the suO1 gene produce cleistothecia containing a reduced number of viable ascospores during the sexual cycle. The segregation of the genetic markers has also been observed in the mutant strain self crossed. From the above results it may be concluded that suO1 is an informational suppressor.

Mechanisms of resistance to fluoroquinolones.

Fluoroquinolones have some of the properties of an 'ideal' anti-microbial agent. Because of their potent broad spectrum activity and absence of transferable mechanism of resistance or inactivating enzymes, it was hoped that clinical resistance to this useful group of drugs would not occur. However, over the years, due to intense selective pressure and relative lack of potency of the available quinolones against some strains, bacteria have evolved at least two mechanisms of resistance: (i) alteration of molecular targets, and (ii) reduction of drug accumulation. DNA gyrase and topoisomerase IV are the two molecular targets of fluoroquinolones. Mutations in specified regions (quinolone resistance-determining region) in genes coding for the gyrase and/or topoisomerase leads to clinical resistance. An efflux pump effective in pumping out hydrophilic quinolones has been described. Newer fluoroquinolones which recognize both molecular targets and have improved pharmacokinetic properties offer hope of higher potency, thereby reducing the probability of development of resistance.

Incidência de S aureus Meticilino-resistente (MRSA) em estetoscópios de uso hospitalar / Methicillin-resistant (MRSA) S aureus

Foram colhidas prospectivamente 150 amostras para cultura de microrganismos de estetoscópios utilizados rotineiramente no hospital por acadêmicos de Medicina, médicos e enfermeiros. Realizou-se in print direto do diagragma e swab das reentrâncias dos estetoscópios em meio de cultura ágar-sangue. Os germes foram identificados através das provas padrões. A resistência à oxacilina/meticilina foi identificada por antibiograma através do método de Kirby-Bauer e semeadura em spot. Neste estudo os estetoscópios demonstraram ser reservatórios de agentes infecciosos, demonstrando bactérias em 91,3 por cento deles. A incidência em médicos, acadêmicos e enfermeiros foi, respectivamente, 87,9 por cento, 89,3 por cento e 97,7 por cento, nos diafragmas, e 96,5 por cento, 91,3 por cento e 75 por cento, respectivamente, nas reentrâncias. Entre os estafilococos presentes, 7,3 por cento eram meticilino-sensíveis e 2 por cento eram meticilino-resistentes no diafragma, e 5,3 por cento meticilino-sensíveis e 1,3 por cento meticilino-resistentes nas reentrâncias. Os autores sugerem a desinfecção do diafragma com álcool a 70 por cento antes do atendimento de cada paciente para evitar a possível disseminação destes germes

Quinolonas y terapia antimicrobiana / Quinolones and anti-microbian therapy

Se revisan las características químicas y el mecanismo de acción de las quinolonas y se hace hincapié en las fluoroquinolonas. Se comentan los aspectos más importantes en relación con su actividad in vitro, así como sus características farmacológicas más importantes. Se señalan las indicaciones más frecuentes y se especifican en algunos casos las dosis y las vías de administración. Se reseñan los efectos adversos más comunes y se hace una breve revisión de algunas de las nuevas quinolonas en fase de experimentación

Principios generales de la terapéutica antimicrobiana / General principles of antimicrobial therapauetics

Se revisan las generalidades de la terapéutica antimicrobiana. Se señalan los diferentes mecanismos de acción y las clasificaciones que más se utilizan de estos fármacos. Además, se revisan los mecanismos de resistencia de los antibióticos y se resumen las manifestaciones de toxicidad más frecuentes de los antibióticos de mayor uso

Antimicrobial resistance patterns of Bacteroides fragilis group organisms in Korea

Antimicrobial resistance patterns of 913 clinical isolates of Bacteroides fragilis group organisms were monitored during an 8-year period in Korea. In general the resistance rates of the non-fragilis B. fragilis group species were higher than those of B. fragilis for all the drugs tested. The rate of resistance to clindamycin remarkably increased and those to some beta-lactam drugs such as piperacillin and cefotaxime also increased. No isolates were found to be resistant to imipenem, metronidazole, or chloramphenicol. beta-lactam and beta-lactamase inhibitor combinations and cefoxitin were more active than the other beta-lactams. Therefore, these agents may be considered when empirical selection of antimicrobial agents is required to treat severe anaerobic infections.

Nocardia osteomyelitis in a pachymeningitis patient: an example of a difficult case to treat with antimicrobial agents

Antimicrobial agents played a miraculous role in the treatment of bacterial infections until resistant bacteria became widespread. Besides antimicrobial-resistant bacteria, many factors can influence the cure of infection. Nocardia infection may be a good example which is difficult to cure with antimicrobial agents alone. A 66-year-old man developed soft tissue infection of the right buttock and thigh. He was given prednisolone and azathioprine for pachymeningitis 3 months prior to admission. Despite surgical and antimicrobial treatment (sulfamethoxazole-trimethoprim), the infection spread to the femur and osteomyelitis developed. The case showed that treatment of bacterial infection is not always as successful as was once thought because recent isolates of bacteria are more often resistant to various antimicrobial agents, intracellular parasites are difficult to eliminate even with the active drug in vitro, and infections in some sites such as bone are refractory to treatment especially when the patient is in a compromised state. In conclusion, for the treatment of infections, clinicians need to rely on laboratory tests more than before and have to consider the influence of various host factors.

Surveillance of resistant pathogens and rational use of antibiotics: general remarks

Surveillance of resistant pathogens should lead to improved treatment of patients and to a rational use of antibiotics. The process for decision making between microbiology, general practice and health policy is still to be documented with careful studies.