Frecuencia y susceptibilidad a penicilina y meticilina de aislamientos ambientales de Staphylococcus aureus en un hospital de Cuenca / Frequency and susceptibility to penicillin and methicillin of Staphylococcus aureus environmental isolations at a Cuenca´s hospital

Staphylococcus aureus es un patógeno asociado con infecciones intrahospitalarias comúnmente hallado en las fosas nasales y las manos del personal de salud; así como, en superficies ambientales, las cuales se convierten en potenciales reservorios y vehículos de transmisión de infecciones. En este estudio se analizó la frecuencia y la susceptibilidad a penicilina y meticilina de aislamientos ambientales de S. aureus en un hospital de Cuenca. Se recolectaron 50 muestras (30 de dos quirófanos y 20 de la sala de cuidados intensivos). S. aureus se identificó por pruebas fenotípicas y detección molecular del gen nuc. La susceptibilidad a meticilina y penicilina se determinó por el método de difusión del disco en agar y los genes blaZ y mecA por reacción en cadena de la polimerasa. La frecuencia de S. aureus fue de 6% (3/50 cepas). La resistencia a penicilina y meticilina fue de 66,6% (2/3 cepas). Los genes blaZ y mecA se detectaron en las dos cepas resistentes a penicilina y meticilina. La baja frecuencia de S. aureus puede estar relacionada con los ambientes analizados; ya que, las superficies muestreadas son áreas donde se hace énfasis en la aplicación de protocolos de higiene y desinfección para asegurar una adecuada descontaminación

Staphylococcus aureus is a pathogen associated with intrahospital infections commonly found in the nasal cavities and the hands of health personnel, as well as, on environmental surfaces; which become potential reservoirs and transmission vehicles of infections. In this study the frequency and susceptibility to penicillin and methicillin of environmental isolates of S. aureus in a hospital to Cuenca were analyzed. 50 samples (30 of two operating room and 20 of the intensive care room) were collected. S. aureus was identified by phenotypic tests and molecular detection of the nuc gene. The susceptibility to methicillin and penicillin was determined by agar disc diffusion method and the blaZ and mecA genes by polymerase chain reaction. The frequency of S. aureus was 6% (3/50 strains). Resistance to penicillin and methicillin was 66.6% (2/3 strains). The blaZ and mecA genes were detected in the two strains resistant to penicillin and methicillin. The low frequency of S. aureus may be related to the environments analyzed; because the surfaces sampled are areas where emphasis is placed on the application of hygiene and disinfection protocols for ensure adequate decontamination

Alta prevalência de crianças portadoras de Streptococcus pneumoniae resistentes à penicilina em creches públicas / High prevalence of children colonized with penicillin-resistant Streptococcus pneumoniae in public day-care centers

OBJETIVOS: Investigar a prevalência de Streptococcus pneumoniae (pneumococos) na nasofaringe de crianças sadias atendidas em creches municipais da cidade de Umuarama (PR). Avaliar a susceptibilidade aos antimicrobianos dos pneumococos isolados. MÉTODOS: Secreção da nasofaringe de 212 crianças foi coletada no período de abril a outubro de 2008. Após semeadura dos espécimes em ágar sangue e incubação a 37 °C por 24-48 horas, as colônias suspeitas de pertencerem a S. pneumoniae foram identificadas pela α-hemólise, sensibilidade à optoquina e bile solubilidade. A susceptibilidade à penicilina foi investigada pelos testes de disco-difusão e de diluição. A susceptibilidade aos demais antimicrobianos indicados no tratamento das infecções pneumocócicas foi realizada por disco-difusão RESULTADOS: A prevalência de pneumococos na nasofaringe foi de 43,4 por cento (92/212), sendo maior em crianças com idade entre 2 e 5 anos (p = 0,0005). Não houve diferença significativa entre os sexos. Resistência intermediária e resistência plena à penicilina foram encontradas respectivamente em 34,8 (32/92) e 22,8 por cento (21/92) dos isolados. Sessenta e sete amostras (72,8 por cento) foram resistentes ao sulfametoxazol-trimetoprim, oito (8,7 por cento) à eritromicina e seis (6,5 por cento) à tetraciclina. Uma amostra apresentou resistência à clindamicina (1,1 por cento), e outra ao cloranfenicol (1,1 por cento). Todas as amostras foram sensíveis a levofloxacina, ofloxacina, rifampicina, telitromicina, linezolide e vancomicina. Nove amostras foram consideradas multirresistentes, por apresentarem resistência a três ou mais classes de antimicrobianos. CONCLUSÕES: O presente estudo registrou uma alta prevalência de crianças portadoras sadias de amostras de S. pneumoniae resistentes à penicilina que podem constituir importantes reservatórios desse patógeno na comunidade.

OBJECTIVES: To investigate the prevalence of Streptococcus pneumoniae (pneumococci) in the nasopharynx of healthy children enrolled in public day-care centers of the municipality of Umuarama, state of Paraná, Brazil. The susceptibility of the pneumococcal strains to antimicrobial agents was also studied. METHODS: Nasopharyngeal specimens from 212 children were collected from April to October 2008. After the specimens were seeded in blood agar and incubated at 37 °C for 24-48 hours, the colonies suspected of belonging to S. pneumoniae were identified using α-hemolysis, optochin sensitivity, and bile solubility test. Penicillin susceptibility was investigated using the disk diffusion and dilution tests. Susceptibility to the other antimicrobial agents indicated for the treatment of pneumococcal infections was investigated using the disk diffusion test. RESULTS: The prevalence of nasopharyngeal pneumococci was 43.4 percent (92/212), with higher rates in children between 2 and 5 years old (p = 0.0005). There was no significant difference between sexes. Intermediate and full resistance to penicillin were found in 34.8 (32/92) and 22.8 percent (21/92) isolates, respectively. Sixty-seven strains (72.8 percent) were resistant to sulfamethoxazole-trimethoprim, eight (8.7 percent) were resistant to erythromycin, and six (6.5 percent) to tetracycline. One strain was resistant to clindamycin (1.1 percent) and another was resistant to chloramphenicol (1.1 percent). All strains were sensitive to levofloxacin, ofloxacin, rifampicin, telithromycin, linezolid, and vancomycin. Nine strains were considered multiresistant because they were resistant to three or more classes of antimicrobial agents. CONCLUSIONS: The present study detected a high prevalence of healthy children colonized with penicillin-resistant S. pneumoniae strains who may be important reservoirs of this pathogen in the community.

Distribución de serotipos y patrón de sensibilidad in vitro a diferentes antibióticos de cepas de Streptococcus pneumoniae obtenidas de niños menores de 15 años en aislamientos invasores en el departamento de Risaralda, 1999 a 2004 / Serotype Distribution and in Vitro Antibiotic Sensitivity of Streptococcuspneumoniae Strains from Invasive Disease Isolates among Children Under 15Years Old, in Risaralda, Colombia, 1999 to 2004

Objetivo. Identificar las cepas prevalecientes de Streptococcus pneumoniae causantes de enfermedad invasiva y su patrón de sensibilidad a la penicilina en niños menores de 15 años que habitan el departamento de Risaralda. Método. Análisis descriptivo a partir de muestras de fluidos estériles analizados por el Instituto Nacional de Salud dentro de su programa de vigilancia epidemiológica del neumococo, y provenientes de niños menores de 15 años del departamento de Risaralda durante los años 1999 a 2004. Resultados. Las cepas prevalentes de S. pneumoniae en Risaralda no son diferentes a las halladas en otras regiones del país. La tasa de resistencia del neumococo aislado en fluidos estériles por ciento - 26,2 por ciento). Para menores de 5 años fue de 35 por ciento. No hay datos de sensibilidad a las cefalosporinas de tercera generación. Conclusión. La implementación de un programa de vacunación contra neumococo en el departamento del Risaralda prevendría en un alto porcentaje la posibilidad de adquirir enfermedad invasiva. Dado el alto índice de resistencia a la penicilina, los esquemas antibióticos empíricos para enfermedad invasiva por neumococo en menores de 5 años deben incluir la vancomicina y las cefalosporinas de tercera generación hasta que se obtengan cultivos definitivos

AbstarctObjective: To identify the most prevalent sero-types and in vitro antimicrobial susceptibility topenicillin and other antibiotics in children under 15years old who have Streptococcus pneumoniaeinvasive disease and live in the department ofRisaralda (Colombia). Method: We reviewed thedata analyzed by the Instituto Nacional de Saludfrom S. pneumoniae sterile fluid's isolated during5 years (1999 to 2004). Results: Most prevalentserotypes of S. pneumoniae in Risaralda are notdifferent from others departments of Colombia. Itsresistance to penicillin was 22% for all childrenand 35% for children under 5 years old. 7.5% ofthe isolates had intermediated sensitivity toceftriaxone. Conclusions: An immunization pro-gram in children under 5 years old in Risaraldawould prevent a lot of cases of invasive disease byS. pneumoniae. The empiric treatment of S. pneu-moniae Invasive Disease in children under 5 yearsold in Risaralda would include vancomycin plus athird generation cephalosporins until antibiogramis developed

Perfil de sensibilidade em infecções pneumocócicas e análise da conduta terapêutica em hospital de referência em doenças infecciosas / Management of pneumococal infectious according to the sensibility profile in a state reference hospital for infectious disease

Com o advento da resistência do Streptococcus pneumoniae (pneumococo) à penicilina, o tratamento empírico inicial tornou-se complexo, sendo fundamental a determinação do perfil de sensibilidade em cada instituição, visando à adequada abordagem terapêutica deste agente. Objetivo: Analisar, em hospital de referência em doenças infecciosas, a conduta terapêutica instituída diante das infecções por Streptococcus pneumoniae, avaliando a influência do conhecimento do perfil de sensibilidade deste agente e das condições clínicas dos pacientes. Método: Estudo observacional de crianças hospitalizadas no Centro Geral de Pediatria (FHEMIG-BH), no período de 2000 a 2001. Resultado: Isolou-se o pneumococo em 33 crianças (57,6% com pneumonia e 42,4% com meningite). A infecção por pneumococo resistente à penicilina (MIC≥2,0 mg/ml) ocorreu em 9,1%, nos quais o tratamento foi modificado diante da piora clínica e do padrão de sensibilidade. Em 27,3% dos casos, isolou-se cepa com sensibilidade intermediária (MIC:0,1 a 1,0 mg/ml). Entre estes, 55,6% mantiveram o tratamento com penicilina na dose habitual, com boa evolução clínica. Nos demais com sensibilidade intermediária, houve alteração da antibioticoterapia. Cepas de pneumococos foram sensíveis (MIC≥ 0,06 mg/ml) em 63,6% das infecções e o uso da penicilina obteve bons resultados. Conclusões: A prevalência de cepas resistentes foi relativamente baixa (9,1%). Dos pacientes infectados por pneumococos com sensibilidade intermediária à penicilina, 55,6% apresentaram resposta clínica satisfatória com dose habitual deste antibiótico.

Management of pneumococcal infections according to the sensibility profile in State reference hospital for infectious disease. In troduction: The prevalence of infections due to Streptococcus pneumoniae with reduced susceptibiliry to penicillin is increasing what makes the empiric treatment a complex issue. Each institution should determine the sensibililty profile of this bacteria to estabilish the best management of these infections. Objectives: To know, in a State reference hospital for infectious disease, the sensibility profile of S. pneumoniae and to estabilish its correlation with clinical aspects. Methods: retrospective study of inpatients in Centro Geral de Pediatria (CGP - FHEMIG- Brazil) during the period of 2000 to 2001. Results: Pneumococcus was isolated in 33 children; 57.6% with pneumonia and 42.4% with meningitis. Penicillin resistant pneumococci (MIC > 2 µg/mIL were found in 9.1%. The therapy was changed according to the sensibility profile and clinical course of the illness. In 27.3% of the children, S. pneumoniae with reduced susceptibility to penicillin (MIC 0.1- 1,0 µg/mL) was isolated: 55.6% of the patients improved with penicillin in usual doses and the others had the antibiotic changed. In 63.6% of the patients. S. pneumoniae was sensitive to penicillin (MIC< 0.1µg/mL.]). Most of them used penicillin and the outcome was uneventful. Conclusions: The prevalence of penicillin resistant pneumococcus was relatively low (9.1%). Most patients with infections with pneumococcus with reduced susceptibility to penicillin (55.6%) got well using the standard therapy with this antibiotic.

Estafilococos y enterococos: ¿amenazas a la salud pública?: epidemiología y mecanismos de resistencia a los antibióticos / Staphylococci and enterococci: threats to public health?: epidemiology and mechanisms of resistance to antibiotics

La resistencia a los antimicrobianos se está convirtiendo en un problema de salud emergente. Las especies de estafilococos y enterococos son microorganismos causantes de múltiples y frecuentes infecciones en el ser humano, principalmente a nivel nosocomial. El Staphylococcus aureus ha adquirido mecanismos de resistencia a la penicilina, a las penicilinas resistentes a las penicilinasas -meticilina- (SAMR), y recientemente, a la vancomicina (VISA). El enterococo es intrínsecamente resistente a gran variedad de agentes antimicrobianos y ha adquirido resistencia a betalactámicos, aminoglicósidos y glicopéptidos. Múltiples mecanismos explican la adquisición, desarrollo y diseminación de la resistencia. Existen en el momento pocas alternativas para tratar infecciones producidas por microorganismos resistentes y las medidas en el momento se deben dirigir al control del uso de antibióticos y prevención de la diseminación. Se realiza una revisión de la epidemiología, mecanismos de resistencia, opciones de tratamiento y medidas de control de estos microorganismos.

Antimicrobial resistance is becoming an emerging health problem. Gram-positive cocci are bacterias which cause multiple and frequent infections in the human being, specially nosocomialleveL Staphylococcus aureus has acquired resistance mechanisms to penicillins,methicillin (MRSA) and recently to vancomycin (VISA). Enteroccocus spp is intrincically resistant to a great variety of antimicrobial agents and it has acquired resistance to betalactamics, aminoglycosides and glycopeptides. Multiple mechanisms explain theacdquisition, development and spread of resistance. At the moment there are a few alternatives to treat infections produced by resistant bacterias and the measurements should be directed to the control in the antibiotics use and infection control practice. This reviewattempts to point out the edpidemiology, resistance mechanisms treatment options and prevention means of these microorganisms.

Estafilococos multirresistentes: uso del disco de oxacillín como marcador de resistencia a antibióticos

Se estudió la susceptibilidad in vitro de cepas pertenecientes al género Staphylococcus frente a diferentes antibióticos y se hizo énfasis en la vancomicina y la penicilina a partir del grado de resistencia presentado frente al oxacillín. Se utilizaron 200 cepas de estafilococos, 100 de ellas pertenecientes a la especie Staphylococcus aureus y otras 100 a estafilococos coagulasa negativos. El origen de las cepas fue tanto intrahospitalario como comunitario. Se observó resistencia notable al oxacillín, altísima frente a la penicilina e incipiente a la vancomicina por parte de las cepas estudiadas, sobre todo en estafilococos coagulasa negativos. Las cepas oxacillín-resistentes mostraron los valores más altos y un amplio espectro de resistencia a los antibióticos.

The susceptibility in vitro of strains belonging to the genus Staphylococcus was studied by using different antibiotics. Emphasis was made on vancomycin and penicillin based on the degree of resistance to oxacillin. 200 strains of staphylococci were used. l00 of them belonging to the Staphylococcus aureus species and the other 100 to coagulase-negative staphylococci. The strains had an intrahospital and community origin. The rates of resistance observed among the studied strains, mainly the coagulase-negative staphylococci, were as follows: significant to oxacillin, very high to penicillin and incipient to vancomycin. The oxacillin-resistant strains showed the highest values and a wide spectrum of resistance to antibiotics.

Neumococo resitente ¡alarma mundial

: Se realizó un análisis cronológico del Streptococo pneumoniae resistente a la penicilina y se incluyen su expansión mundial, su mecanismo de resistencia, posibles causas de aparición y conducta ante las sepsis por dichas cepas, así como medidas para contrarrestar su ascenso.

: A chronological analysis of the Streptococcus pneumoniae resistant to penicillin was made. Its world spread, resistance mechanism, possible causes of appearance, behaviour before the sepses caused by such strains, and the measures to counteract its rise were also included.