Francisco Silva

Natural and synthetic xanthones as monoamine oxidase inhibitors: Biological assay and 3D-QSAR

Fifty-nine xanthones (= 9H-xanthen-9-ones) of natural or synthetic origin were investigated for their inhibitory activity toward monoamine-oxidase A (MAO-A) and MAO-B. The compounds demonstrated reversible. time-independent activities, with selectivity toward MAO-A. The most active inhibitor had an IC50 of 40 nM. Electron absorption spectroscopy revealed the formation of a 1:1 charge-transfer complex between lumiflavine and xanthones. 3D-QSAR Studies according to the CoMFA/GOLPE procedure provided information on the relationship between steric and electrostatic fields and MAO-A inhibition. The ALMOND procedure yielded additional topographical information on structural factors favoring activity

First isolation of kpc in Chile: from Italy to a public hospital in Santiago

Carbapenem resistance in Enterobacteriaceae is an emerging problem worldwide. Among the mechanisms involved are the production of ESBLs or AmpC associated with porins loss or the presence of carbapenemases. Among these, the KPC betalactamase has become especially relevant given its rapid spread.In this article we present the first case of isolation of a strain of KPC producer Klebsiella pneumoniae at a hospital in Santiago, in a patient coming from Italy, with a history of multiple hospitalizations for treatment of non-Hodgkin lymphoma and subjected to several cycles of chemotherapy and hemodialysis. The strain was isolated from a urine culture on the seventh day of the patients arrival to Chile. The isolate was resistant to quinolones, aminoglycosides, cephalosporins and carbapenems, retaining only susceptibility to tigecycline and colistin. In phenotypic test it was found to have positive Hodge test and positive synergy with carbapenems/boronic acid. Polymerase chain reaction demonstrated the presence of beta-lactamases TEM, SHV and KPC-2. None other Class A serine-carbapenemase or metallo-bectalactamases were present.

Outbreak of Paecilomyces variotii Peritonitis in Peritoneal Dialysis Patients after the 2010 Chilean Earthquake

Fungal peritonitis (FP) accounts for 3 - 6% of all peritonitis episodes in chronic peritoneal dialysis (PD), being associated with high morbidity and mortality. Mortality rates are in the range of 15 - 50%, and loss of the peritoneal membrane function can be over 40% (1). The most common cause of the disease is Candida species (C. albicans, C. parapsilosis, C. glabrata). Other yeasts and filamentous fungi such as Aspergillus, Paecilomyces, Penicillium, and Zygomycetes are found less frequently. The strongest risk factors for FP in PD patients are prolonged use of antibiotics and previous bacterial peritonitis (2). Other suggested risk factors are immunosuppression, malnutrition, bowel perforation, diverticulitis, and, possibly, certain comorbidities such as diabetes or neoplastic diseases (1). Paecilomyces spp is a filamentous fungus like the genus Penicillium and Aspergillus. It is found in soil and water and is one of the main dwellers of house dust. It is rarely associated with human infections. When a disease does occur, it is more often related to foreign bodies or immunosuppressed patients (3,4). After the earthquake of February 27, 2010, in Chile, there was an increase in the rate of FP from 1% to 6%, due to the appearance of 6 cases caused by Paecilomyces variotti (5). Here we describe the clinical characteristics and outcomes of 3 of these patients. Although there was no proof of the precise route of infection in our patients, in all 3 cases there was a major alteration in the storage of the PD fluid bags, resulting especially in exposure to excessive dust and destruction of the architecture of the storage holds. It is quite possible that in the context of a natural disaster like a big earthquake, the risk of infections associated with this fungus could increase because of the excessive dust in the environment.

Susceptibilidad antimicrobiana en Chile 2012

La resistencia bacteriana es un problema de salud publica que lejos de estar controlado, aumenta en cantidad y complejidad. El Grupo Colaborativo de Resistencia, es un conjunto de profesionales que representan a 39 establecimientos de salud del pais y que se ha ocupado desde 2008 de recolectar informacion sobre la susceptibilidad antimicrobiana de bacterias en Chile. En este documento se presenta la susceptibilidad in vitro acumulada del ano 2012, de 28 establecimientos de salud del pais que representan, al menos, 36% de los egresos hospitalarios de Chile. Consideramos de la mayor relevancia reportar periodicamente la susceptibilidad bacteriana de modo de mantener a la comunidad medica actualizada para orientar las terapias empiricas y las medidas de control y prevencion de la diseminacion de cepas multi-resistentes.

Grupo Colaborativo de Resistencia Bacteriana, Chile: recomendaciones 2014 para el control de la resistencia bacteriana

Five issues were reviewed in depth at the 2014 annual meeting of Colaborative Group Against Bacterial Resistance and the antecedents and conclusions are detailed in this document. I.- News in CLSI 2014: the difficulties and implications on its implementation at the local level were reviewed and recommendations were set. II.- Criteria for determining the incidence of multi-resistant microorganism in critical care units where indicators and monitoring methodology for better quantification of microorganisms were defined. III.- Quality requirements were established to be considered by the professionals involved in the selection of antimicrobials in the hospital. IV.- Transfer policies, screening and contact precautions for the control of transmission of multiresistant bacteria. V.- Recommendations for health facilities when a carbapenemase producing enterobacteriacea is detected, in a checklist format for rapid deployment in hospitals without endemia of these agents. These are suggestions that arise from the joint work of specialists from many hospitals that do not represent consensus or recommendation, but may help to control the resistance level of each health facility in the country.

Detección de serinocarbapenemasas de clase A y otros mecanismos de resistencia enzimática a β-lactámicos en cepas de enterobacterias con susceptibilidad disminuida a carbapenémicos, aisladas de pacientes de un hospital universitario de Santiago, Chile

Introduccion: La emergencia de resistencia a β-lactamicos por carbapenemasas en enterobacterias tiene gran importancia clinica. El objetivo de este estudio fue caracterizar genotipica y fenotipicamente la resistencia enzimatica a β-lactamicos en enterobacterias con susceptibilidad disminuida a carbapenemicos, en cepas aisladas de pacientes de un hospital universitario de Santiago. Metodologia: Durante abril-septiembre 2010, en el Hospital Clinico de la Universidad de Chile se recolectaron 23 aislados. Se detectaron serinocarbapenemasas clase A (SME, IMI, NMC, GES y KPC) mediante RPC. Se empleo el test de Hodge modificado y acido fenil-boronico (APB) para la deteccion fenotipica de serinocarbapenemasas. Se detecto la presencia de β-lactamasas de espectro extendido segun CLSI y AmpC y MBL mediante tabletas comerciales. Resultados: 18 cepas (78,26%) correspondieron a Klebsiella pneumoniae y 5 cepas (21,74%) a Enterobacter cloacae. Todas las RPC para serinocarbapenemasas fueron negativas, en tanto, el test de Hodge fue positivo para 3/23 cepas, todas E. cloacae. Una cepa de K. pneumoniae fue positiva para APB. Se detecto BLEE en 14/23 cepas, AmpC en 5/23 cepas y no se detecto MBL. Conclusiones: En las cepas estudiadas no se detectaron serinocarbapenemasas clase A. Probablemente los mecanismos que explican la susceptibilidad disminuida a carbapenemicos, involucran resistencia enzimatica, combinados con cambios en la permeabilidad de la membrana bacteriana.

Incidencia de bacterias multi-resistentes en unidades de cuidados intensivos de hospitales chilenos

INTRODUCTION Incidence of multi-resistant bacteria is an indicator that permits better estimation of the magnitude of bacterial resistance in hospitals. AIM To evaluate the incidence of relevant multi-drug resistant bacteria in intensive care units (ICUs) of Chile. METHODS Participating hospitals submitted information about the number of isolates from infected or colonized patients with 7 epidemiologically relevant multi-resistant bacteria in adult and pediatric ICUs between January 1, 2014 and October 31, 2015 and the number of bed days occupied in these units in the same period was requested. With these data incidence was calculated per 1,000 patient days for each unit. RESULTS Information from 20 adults and 9 pediatric ICUs was reviewed. In adult ICUs the bacteria with the highest incidence were K. pneumoniae ESBL [4.72 × 1,000 patient day (1.21-13.89)] and oxacillin -resistant S. aureus [3.85 (0.71-12.66)]. In the pediatric units the incidence was lower, highlighting K. pneumoniae ESBL [2.71 (0-7.11)] and carbapenem -resistant P. aeruginosa [1.61 (0.31-9.25)]. CONCLUSION Important differences between hospitals in the incidence of these bacteria were observed. Incidence of multi-resistant bacteria in adult ICU was significantly higher than in pediatric ICU for most of the studied bacterias.INTRODUCTION Incidence of multi-resistant bacteria is an indicator that permits better estimation of the magnitude of bacterial resistance in hospitals. AIM To evaluate the incidence of relevant multi-drug resistant bacteria in intensive care units (ICUs) of Chile. METHODS Participating hospitals submitted information about the number of isolates from infected or colonized patients with 7 epidemiologically relevant multi-resistant bacteria in adult and pediatric ICUs between January 1, 2014 and October 31, 2015 and the number of bed days occupied in these units in the same period was requested. With these data incidence was calculated per 1,000 patient days for each unit. RESULTS Information from 20 adults and 9 pediatric ICUs was reviewed. In adult ICUs the bacteria with the highest incidence were K. pneumoniae ESBL [4.72 × 1,000 patient day (1.21-13.89)] and oxacillin -resistant S. aureus [3.85 (0.71-12.66)]. In the pediatric units the incidence was lower, highlighting K. pneumoniae ESBL [2.71 (0-7.11)] and carbapenem -resistant P. aeruginosa [1.61 (0.31-9.25)]. CONCLUSION Important differences between hospitals in the incidence of these bacteria were observed. Incidence of multi-resistant bacteria in adult ICU was significantly higher than in pediatric ICU for most of the studied bacterias.

Brucelosis en Chile: Descripción de una serie de 13 casos

INTRODUCTION Brucellosis is a zoonosis caused by Brucella spp. It may be acquired by consuming unpasteurized dairy products. Brucellosis has a low incidence in Chile, thus, we have a scarce data. AIM To report and to characterize the first series of clinical cases of adult patients diagnosed with brucellosis in Chile. METHODS We describe a series of 13 clinical cases in patients diagnosed between 2000 and 2016 in three different centers in the Metropolitan Region, Chile. A retrospective analysis was performed on clinical presentation, laboratory, antibiotic treatment, morbidity and mortality. RESULTS The mean age was 50 years old. Eight cases had a record of consumption of unpasteurized dairy products. The most frequently reported complaints were fever. The most frequent focal point involved was the spine. Only one patient had a positive blood culture, while the diagnosis was made using serological techniques in the other part of the group. The most indicated antibiotic regimens were doxycycline-rifampicin and doxycycline-gentamicin. The hospital stay was 20 days approximately as an average. Clinical cure was achieved in all cases. CONCLUSIONS Brucellosis is an infrequent zoonosis in Chile, and it produces a nonspecific clinical picture, so it is necessary to have high suspicion to make the diagnosis based in the antecedent of consumption of unpasteurized dairy or raw meat.

Ventilator-associated pneumonia after elective cardiac surgery caused by Pneumocystis jirovecii

Ventilator-associated pneumonia is a severe complication among patients undergoing cardiac surgery. Although hospital-acquired bacterial pathogens, often multidrug resistant, are the most frequent cause, non-bacterial atypical and opportunistic agents traditionally associated with immunocompromise are increasingly recognized. We describe ventilator-associated pneumonia due to Pneumocystis jirovecii in the absence of traditional risk factors for Pneumocystis pneumonia in a patient after cardiac surgery.