Emergence and clonal spread of KPC-2-producing clinical Klebsiella aerogenes isolates in a hospital from northwest Argentina.

Introduction. Klebsiella aerogenes is a nosocomial pathogen associated with drug resistance and healthcare-associated infections.Gap Statement. K. aerogenes is associated with hospital-acquired infections with the ability to acquire mechanisms of resistance to reserve antimicrobials; its clinical behaviour has been poorly documented.Objective. We proposed to investigate an outbreak of carbapenem-resistant K. aerogenes in a hospital that persisted for 4 months.Methods. The primary aim was to evaluate the molecular characteristics and the clonal relationships among the isolates. We characterized isolates by polymerase chain reaction (PCR) and pulsed-field gel electrophoresis (PFGE). The information was integrated with clinical and epidemiological data.Results. Fourteen strains were disseminated in an intensive care unit and different wards at the hospital. The overall mortality was 42.8 %, and mortality attributed to infection was 21.4 %; strains showed high rates of resistance to most of the antimicrobials tested and carried bla KPC-2, bla SHV-2 and bla CTXM-15 genes. PFGE analysis indicated 2 PFGE groups; 12/14 isolates were associated with subgroup A and were likely to be primarily responsible for the first isolation and subsequent dissemination. The outbreak characteristics data showed prolonged hospitalization and previous use of antibiotics as potential risk factors.Conclusion. We consider that it is essential to perform phenotypic and genotypic identification of early genetic resistance mechanisms in K. aerogenes isolates, not only from infection sites but also from colonization, to prevent the spread of these multidrug-resistant (MDR) isolates.

Aceites esenciales con actividad antibacteriana: posible aplicación y administración en odontología / Essential oils with antibacterial activity: possible uses and administration in the dental practice

Resumen Introducción la caries dental es una de las enfermedades de mayor prevalencia a escala mundial, cuyas consecuencias clínicas se encuentran relacionadas directamente con la calidad de vida de los individuos. Asimismo, la atención odontológica exige un elevado costo y muchas veces lejos del alcance de ciertas comunidades. Si bien esta enfermedad se produce por la confluencia de distintos factores, uno de ellos es el económico, por lo que se busca una opción medicinal de bajo costo, y el abordaje a su vez de otro factor, tal vez el más importante, que implica el desarrollo y multiplicación del microorganismo iniciador de esta enfermedad, que es Streptococcus mutans. Actualmente se conoce el consumo de medicinas de origen natural para el tratamiento de algunas enfermedades, entre ellas, la caries. El uso y mecanismo de acción de aceites esenciales que impidan el desarrollo de S. mutans en el biofilm dental está siendo investigado. El objetivo de este trabajo es actualizar los conocimientos sobre la acción biocida de aceites esenciales y sus posibles aplicaciones en odontología. Resultados. Los aceites esenciales provenientes de los cítricos como limón, mandarina, naranja, como así también de eucalipto y orégano, presentan actividad bacteriostática, y en algunos casos, bactericida frente a bacterias Gram + y Gram -. Conclusión de acuerdo con la información recopilada, el uso de estos aceites mediante la biotecnología sería beneficioso y contribuiría al manejo de la salud bucal sin alterar la microflora oral normal del ser humano.

Abstract Dental caries is one of the most prevalent diseases worldwide, whose clinical consequences are directly related to the quality of life of individuals. Likewise, dental care requires a high cost and is often beyond the reach of certain communities. Although this disease is produced by the confluence of different factors, one of them is the economic factor, which is why a low-cost medicinal alternative is sought, and the approach in turn of another factor, perhaps the most important, which implies the development and multiplication of the initiating microorganism of this disease that is Streptococcus mutans. Currently, the consumption of medicines of natural origin is known for the treatment of some diseases, including tooth decay. The use of essential oils that prevent the development of St. mutans in dental biofilm is being investigated and the objective of this work is to update the knowledge about its biocidal action and its applications in dentistry. The objective of this work is to update the knowledge on the biocidal action of essential oils and their possible applications in dentistry. Results The essential oils from citrus fruits such as lemon, mandarin, orange, as well as eucalyptus and oregano, show bacteriostatic activity, and in some cases, bactericidal against Gram + and Gram - bacteria. Conclusion according to the information collected, the use of these oils through biotechnology would be beneficial and would contribute to the management of oral health without altering the normal oral microflora of the human being.

Novel patterns in the molecular epidemiology of KPC-producing Klebsiella pneumoniae in Tucumán, Argentina.

BACKGROUND: In Argentina, there has been an abrupt increase in KPC-2-producing Klebsiella pneumoniae (K. pneumoniae). Tucumán is a multi-border area, so the rapid dissemination of carbapenem-resistant K. pneumoniae is a clinically relevant problem for the region. OBJECTIVES: This study aimed to investigate the epidemiological and molecular patterns of KPC-producing K. pneumoniae clinical isolates collected from different hospitals in Tucumán. METHODS: Carbapenem-resistant K. pneumoniae strains were sequentially and uniquely collected during two time periods. Antibiotic susceptibility was determined by the automated Vitex 2® system and using the standard agar dilution test. Multilocus sequence typing and pulsed-field electrophoresis were used for epidemiological analysis. The genetic structures around blaKPC and the encoding genes of extended-spectrum ß-lactamases were detected by polymerase chain reaction and sequencing. Plasmids were analysed by conjugation and using the plasmid relaxase gene-typing method. RESULTS: All 37 isolates were multidrug resistant, and theblaKPC-2 gene was confirmed in all of them. In 17 isolates (45.9%), the blaCTX-M-2 gene was also amplified, as well as blaSHV-2 in five isolates (13.5%) and blaCTX-M-2/blaSHV-2 in four isolates (10.8%). The molecular epidemiology of the blaKPC-2 gene has resulted in it being associated with an IncL/M transferable plasmid disseminating in various sequence types (STs) (ST17, ST556, ST342, ST147, ST461, ST65, ST15 and ST70), and in a new genetic environment with a 764-bp deletion in the ISKpn7-blaKPC region. CONCLUSIONS: These findings contribute to the understanding of the great diversity of the blaKPC-2-carrying genetic platforms.

Aceites esenciales con actividad antibacteriana: posible aplicación y administración en odontología

Introducción la caries dental es una de las enfermedades de mayor prevalencia a escala mundial, cuyas consecuencias clínicas se encuentran relacionadas directamente con la calidad de vida de los individuos. Asimismo, la atención odontológica exige un elevado costo y muchas veces lejos del alcance de ciertas comunidades. Si bien esta enfermedad se produce por la confluencia de distintos factores, uno de ellos es el económico, por lo que se busca una opción medicinal de bajo costo, y el abordaje a su vez de otro factor, tal vez el más importante, que implica el desarrollo y multiplicación del microorganismo iniciador de esta enfermedad, que es Streptococcus mutans. Actualmente se conoce el consumo de medicinas de origen natural para el tratamiento de algunas enfermedades, entre ellas, la caries. El uso y mecanismo de acción de aceites esenciales que impidan el desarrollo de S. mutans en el biofilm dental está siendo investigado. El objetivo de este trabajo es actualizar los conocimientos sobre la acción biocida de aceites esenciales y sus posibles aplicaciones en odontología. Resultados. Los aceites esenciales provenientes de los cítricos como limón, mandarina, naranja, como así también de eucalipto y orégano, presentan actividad bacteriostática, y en algunos casos, bactericida frente a bacterias Gram + y Gram -. Conclusión de acuerdo con la información recopilada, el uso de estos aceites mediante la biotecnología sería beneficioso y contribuiría al manejo de la salud bucal sin alterar la microflora oral normal del ser humano.

Dental caries is one of the most prevalent diseases worldwide, whose clinical consequences are directly related to the quality of life of individuals. Likewise, dental care requires a high cost and is often beyond the reach of certain communities. Although this disease is produced by the confluence of different factors, one of them is the economic factor, which is why a low-cost medicinal alternative is sought, and the approach in turn of another factor, perhaps the most important, which implies the development and multiplication of the initiating microorganism of this disease that is Streptococcus mutans. Currently, the consumption of medicines of natural origin is known for the treatment of some diseases, including tooth decay. The use of essential oils that prevent the development of St. mutans in dental biofilm is being investigated and the objective of this work is to update the knowledge about its biocidal action and its applications in dentistry. The objective of this work is to update the knowledge on the biocidal action of essential oils and their possible applications in dentistry. Results The essential oils from citrus fruits such as lemon, mandarin, orange, as well as eucalyptus and oregano, show bacteriostatic activity, and in some cases, bactericidal against Gram + and Gram - bacteria. Conclusion according to the information collected, the use of these oils through biotechnology would be beneficial and would contribute to the management of oral health without altering the normal oral microflora of the human being.

[First case of meningitis by Streptococcus suis in the norwest area of Argentina]. / Primer caso de meningitis por Streptococcus suis en el noroeste de Argentina.

Streptococcus suis causes meningitis, bacteremia, endocarditis, endophthalmitis, artrithis and toxic shock in both pigs and human beings. The incidence of this pathogen is increasing worldwide. A case of 54 years old men from a rural zone of Tucumán, Argentina with two days of headache, vomit and photophobia was admitted septic, with purulent meningitis. Streptococcus suis was growth from the blood and cerebrospinal fluid culture. The patient was treated with ceftriaxona and had a good evolution without sequels. This is the first case of S. suis described in the northwest of Argentina and the third of Latin America, and it is emphasized that the occupational contact with pigs is an important background for the initial suspect of this pathogen.

Primer caso de meningitis por Streptococcus suis en el noroeste de Argentina / First case of meningitis by Streptococcus suis in the norwest area of Argentina

Streptococcus suis causes meningitis, bacteremia, endocarditis, endophthalmitis, artrithis and toxic shock in both pigs and human beings. The incidence of this pathogen is increasing worldwide. A case of 54 years old men from a rural zone of Tucumán, Argentina with two days of headache, vomit and photophobia was admitted septic, with purulent meningitis. Streptococcus suis was growth from the blood and cerebrospinal fluid culture. The patient was treated with ceftriaxona and had a good evolution without sequels. This is the first case of S. suis described in the northwest of Argentina and the third of Latin America, and it is emphasized that the occupational contact with pigs is an important background for the initial suspect of this pathogen.

La infección por Streptococcus suis puede causar meningitis, bacteriemia, endocarditis, endoftalmitis, artritis y shock tóxico, tanto en el ser humano como en cerdos. La incidencia de esta zoonosis está aumentando en el mundo. Se presenta el caso de un varón de 54 años de edad, trabajador rural proveniente de la provincia de Tucumán, Argentina, que consultó por cefalea, vómitos y fotofobia de dos días de evolución, constatándose una sepsis de foco meníngeo. Tanto en el cultivo de líquido cefalorraquídeo como en el hemocultivo se aisló S. suis. Se trató con ceftriaxona con buena evolución y sin secuelas. Es el primer caso de S. suis en el noroeste argentino y el tercero en Latinoamérica. Se resalta la importancia del antecedente de exposición laboral a cerdos para la sospecha inicial de este microorganismo.