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Journal Article; English Abstract; Given the relevance of proper clinical validation of Streptococcus bovis, we here consider revising its presence in urine samples in order to determine its relative frequency and the pattern of antibiotic susceptibility. The susceptibility to antibiotics of 91 isolates of S. bovis from urine samples was retrospectively reviewed over a period of 4 years (2012-2015). The mean age of patients was 55 years, 81% of whom were women and 37.4% were hospitalized patients suffering from urological diseases (61%). Susceptibility to penicillin, vancomycin and teicoplanin was 97.8%. Due to the fact that S. bovis can be infrequent in urine isolates and given its presence in patients suffering from urological diseases, further pathogenic studies, showing the true ability of this group of bacteria to produce disease, are required. Yes Dada la importancia de la correcta validación clínica de los aislamientos de Streptococcus bovis, nos planteamos la revisión de su presencia en muestras de orina con el objetivo de conocer su frecuencia relativa y su patrón de sensibilidad antibiótica. Se revisó retrospectivamente la sensibilidad a los antibióticos de 91 aislados de S. bovis recuperados de muestras de orina durante un período de 4 anos ˜ (2012-2015). La media de la edad de los pacientes fue de 55 anos ˜ y en su mayoría fueron mujeres (81%). El 37,4% eran pacientes hospitalizados con enfermedades urológicas (61%). La sensibilidad a penicilina, vancomicina y teicoplanina fue del 97,8%. Aunque S. bovis puede ser poco común en los aislamientos de orina, su presencia en sujetos con enfermedades de base justifica la realización de estudios de patogenicidad que demuestren la verdadera capacidad de producir enfermedad de este grupo de bacterias.

Objetivos: investigar los biotipos de S. mutans aislados de niños con y sin caries dental y determinar su susceptibilidad antimicrobiana. Métodos: este estudio observacional descriptivo incluyó 206 niños entre los 3 y 5 años de dos preescolares en Bogotá, D. C., Colombia. Después de su aislamiento en agar Mitis Salivarius Bacitracina, las cepas S. mutans se identificaron por pruebas bioquímicas y se biotipificaron por el sistema api-ZYM. En todos los aislamientos se determinó por el método de dilución en agar la concentración inhibitoria mínima (CIM) de Penicilina, Amoxicilina, Cefazolina, Eritromicina, Clindamicina, Imipenem, Vancomicina y Teicoplanina. Resultados: Se encontró S. mutans en 30 de los 79 niños sin caries dental (38%) y en 56 de los 127 niños con caries (44,1%). Los niños con caries presentaron un recuento superior de S. mutans en comparación con los niños sin caries (p < 0,05). En total se identificaron 121 cepas de S. mutans en los 86 niños: 43 cepas en los 30 niños sin caries dental y 78 en los 56 niños con caries dental. Las 121 cepas fueron agrupadas en 38 biotipos: 24 en el grupo de caries y 14 en el grupo sin caries. En el grupo de caries los biotipos más frecuentes fueron el XV, XI, XII y XVII, respectivamente, con 26, 12, 11 y 4 cepas y en el grupo sin caries los biotipos más frecuentes fueron el XXVI, XX y XXXVI, respectivamente, con 14, 8 y 7 cepas. Todos los biotipos fueron altamente sensibles a los antimicrobianos evaluados; el 50 y 90% de las cepas S. mutans fueron inhibidas, respectivamente, por concentraciones menores a 0,12 y 1 µg/ml para todos los antimicrobianos estudiados. Para la penicilina, eritromicina e imipenem se obtuvieron los valores promedios más bajos de CIMs. Conclusiones: en la población objeto de estudio se encontró una gran diversidad biotípica, los aislamientos fueron altamente susceptibles a los antimicrobianos evaluados y en cada grupo de pacientes se identificaron patrones únicos que podrían indicar una colonización específica. Objectives: The main objective was to investigate the biotypes of S. mutans isolated from children with and without dental caries and determine its antimicrobial susceptibility. Methods: this descriptive observational study included 206 children aged 3 to 5 years of two preschool institutions in Bogota-Colombia. After isolation on agar Mitis Salivarius Bacitracin, S. mutans strains were identified by biochemical tests and biotyped by the api-ZYM system. The minimal inhibitory concentrations (MICs) of the S. mutans isolates were evaluated against penicillin, amoxicillin, cefazolin, erythromycin, clindamycin, imipenem, vancomycin and teicoplanin by an agar dilution method. Results: S. mutans was found in 30 of the 79 children without dental caries (38%) and in 56 of the 127 children with caries (44.1%). Children with cavities had a higher count of S. mutans compared to children without caries (p < 0.05). A total of 121 strains of S. mutans were identified in 86 children: 43 strains in 30 children with dental caries and 78 in the 56 children with dental caries. The 121 strains were grouped into 38 biotypes: 24 in the group caries and 14 in the group without caries. In the group caries the most common biotypes were the XV, XI, XII and XVII, respectively, with 26, 12, 11 and 4 strains and the group caries the most common biotypes were the XXVI, XX and XXXVI, respectively, with 14, 8 and 7 strains. All biotypes were highly sensitive to all antimicrobials tested; 50 and 90% of S. mutans strains were inhibited by using concentrations lower than 0.12 and 1 µg/ml, respectively, for all antibiotics studied. The lowest MICs average values were obtained for penicillin, erythromycin and imipenem. Conclusions: In the study population a wide variety of biotypes was found, isolates were highly sensitive to antimicrobials evaluated and in each clinical group were identified unique patters that could indicate a specific colonization.

Glycopeptides (vancomycin and teicoplanin) are an alternative therapeutic in the treatment of severe infections by methicillin-resistant S. aureus strains. However, two resistance mechanisms of S. aureus have already been described: low-level resistance, characterized by an abnormal thickening of the cellular wall, present in the VISA strains, and high-level resistance, mediated by the vanA operon, which causes the replacement of D-ala - D-ala terminal residues by D-ala-D-lac, decreasing its affinity for the antibiotic. This review summarizes the history of the emergence of glycopeptide resistance in S. aureus and considers the mechanisms that determine the resistance in these organisms as a background for understanding the need and potential roles of new agents of this kind. Resumen: Los glicopéptidos (vancomicina y teicoplanina) constituyen una alternativa terapéutica en el tratamiento de infecciones severas por cepas de S. aureus resistentes a meticilina. Sin embargo, ya se han descrito dos mecanismos de resistencia en S. aureus: resistencia de bajo nivel, caracterizada por un engrosamiento anormal de la pared celular, presente en las cepas VISA y, resistencia de alto nivel mediada por el operón vanA, que provoca la sustitución de los residuos terminales D-ala-D-ala por D-ala-D-lac, disminuyendo su afinidad por el antibiótico. Esta revisión resume la historia de la aparición de la resistencia a glicopéptidos en S. aureus y considera los mecanismos que determinan la resistencia en estos organismos como base para comprender la necesidad y los potenciales roles de nuevos agentes de esta clase.

Emergency of vancomycin-resistant Enterococcus infections in a teaching hospital in Chile An active surveillance of vancomycin-resistant enterococci (VRE) intestinal colonization in selected group of patients has been developed in Chile since year 2000. Nevertheless, no reports of clinical cases have been published. Aim. To describe main clinical and microbiological features of patients infected by VRE in a tertiary-level teaching Hospital. Patients and methods. Intestinal and clinical samples positive to VRE were provided by laboratory, and a retrospective analysis of potential risk factors, clinical features, treatment and outcomes was performed. Study encompassed years 2001 to 2006. Main results. 23 cases of infections were identified, all cases occurring during 2005 and 2006. Incidence rate was 0.07 and 0.09 cases per 1000 occupied bed-days, respectively. The mean age was 62.0 ± 17 years. A significant proportion of patients had cancer (39.1%), recent surgical procedures (54.1%), were on dialysis (26.1%), or were using steroids (26.1%). Most patients had received 2 or more antimicrobial (87%), almost a third represented transfers from other hospitals and an additional 22% readmissions before 30 days of latest discharge. Patients were mainly hospitalized in the ICU (60.9%) but nearly 30% were associated exclusively to nephrological or onco-hematological wards. Clinical manifestations included bacteremia (30.4%), surgical site infections or abscesses (26.1%), urinary tract infections (26.1%) and others. . Three patients (13%) did not have symptoms. After identification was possible, all isolates were identified as E. faecium (82.6% of total), the rest as Enterococcus sp. Most strains showed intermediate susceptibility to vancomycin (66.7%). For 14 strains studied both with vancomycin and teicoplanin, , phenotype Van B was predominant (85.7%), followed by VanA (7.1%) and VanB/VanD type (7.1%). No molecular studies were performed. Fifteen patients (65.4%) received a surgical and/or medical treatment. A favorable response was observed in 80% of these cases. Eight patients were not treated (34.8%), in 2 cases because of a rapidly-fatal infection. The global risk-fatality ratio for VRE infections was 13% and increased to 42.9% in patients with bacteremia. Microbiological eradication was documented in 52.2%.

Objetivo: averiguar la práctica clínica real del tratamiento en las unidades de cuidados intensivos sobre las infecciones relacionadas con catéteres con teicoplanina o vancomicina desde la perspectiva de un hospital. Como los ensayos clínicos han demostrado que la eficacia de estos glucopéptidos es simular, también se realizó un análisis de minimización de costes. Métodos: Se utilizó una técnica Delphi para obtener las opiniones de nueve médicos en relación a la utilización de recursos asociados con la teicoplanina y vancomicina. Los costes del tratamiento se consideraron como costes de adquisición de medicamento, costes de material y enfermería requeridos para la preparación y la administración y costes de los análisis de laboratorio. Resultados: los médicos tienden a administrar mayores dosis de carga de teicoplanina de las recomendadas en la prospecto de información del medicamento. Aunque la evidencia de la efectividad de la vancomicina deriva principalmente de ensayos que utilizan pautas de múltiples administraciones diarias, cinco médicos lo administraban en pauta de una vez al día. Las medias de costes alcanzaron los 1.272€ con teicoplanina y 1.041€ con vancomicina. Los mayores costes de tratamiento con teicoplanina se derivan de los mayores costes de adquisición del medicamento (1,076€ versus 795€). El tratamiento con vancomicina se asoció a mayores costes de análisis de laboratorio como consecuencia de la mayor frecuencia de monitorización de concentraciones séricas (217€ versus 150€). Conclusión: Este análisis de práctica clínica y costes indicó que las ventajas de la utilización de recursos por los menores análisis de laboratorio redujo parcialmente el mayor coste de adquisición de la teicoplanina. Además de la eficacia y los costes, otros factores tales como vía de administración, perfil del paciente y efectos adversos hacen necesario que se informe de la elección entre teicoplanina y vancomicina. Objectives: To elicit actual clinical practice of treating intensive care unit patients with catheter-related infections with teicoplanin or vancomycin from a hospital perspective. As clinical trials have demonstrated similar efficacy of these glycopeptides, a cost-minimisation analysis was also carried out. Methods: The Delphi survey technique was used to gather the opinion of nine physicians regarding resource utilization associated with teicoplanin and vancomycin. Treatment costs considered were costs of drug acquisition, costs of material and nursing time required for drug preparation and administration, and costs of laboratory tests. Results: Physicians tend to administer higher loading doses of teicoplanin than recommended in the drug information leaflet. Even though evidence of the effectiveness of vancomycin is mainly derived from trials using multiple-daily administration schedules, five physicians administered it on a once-daily basis. Mean treatment costs amounted to 1,272€ with teicoplanin and 1,041€ with vancomycin. Higher treatment costs with teicoplanin arose from more elevated drug acquisition costs (1,076€ versus 795€). Treatment with vancomycin was associated with higher costs of laboratory tests as a result of more frequent monitoring of serum concentrations (217€ versus 150€). Conclusions: This analysis of clinical practice and costs indicated that the resource utilisation advantages from fewer laboratory tests with teicoplanin partially offset higher drug acquisition costs. In addition to efficacy and costs, other factors such as route of administration, patient profile and adverse effects need to inform the choice between teicoplanin and vancomycin.