[Bacteremia and endarteritis cases secondary to Campylobacter spp. in a metropolitan hospital: our experience along a quarter of a century]. / Bacteriemias e infección endovascular por Campylobacter spp: nuestra experiencia en un cuarto de siglo de historia.

Six cases of bacteremia and one of endarteritis were identified between 1986 and 2010 in a general hospital in Chile. Five of these cases occurred during the second half of this timeframe, Campylobacter fetus predominated (5 out of 7) and the majority of the infections presented during warmer months. The mean age was 32.4 years (range 19 to 63) all had comorbidities, and main clinical manifestations included fever with diarrhea. Four patients developed hypotension and two septic shock. The latter, associated to C. fetus bacteremia, died before microbiological diagnosis. Six out of 7 patients received antimicrobial therapy. During 2004 and 2010, the rates of Campylobacter spp. positive stool cultures in the same hospital increased 4 times, suggesting an emerging profile. Bacteremia and endarteritis by Campylobacter spp. can develop in vulnerable patients and manifest as fever with or without diarrhea. Finding curved or spiral shaped gram negative rods in blood cultures leads to suspect this pathogen. Species identification is of utmost importance due to antimicrobial resistance especially in C. jejuni. Prognosis is unfavorable due to host characteristics, and case-fatality rate is high.

Espondilodiscitis causada por Kingella kingae en pediatría: reporte de un caso / Espondilodiskitis caused by Kingella kingae in children: a case report

During the last years, spondilodiskitis due to Kingella kingae has been a new target of interest, since it is the second agent that causes non tuberculous espondilodiskitis in children, after Staphylococcus aureus. Its clinical presentation is very inespecific, sometimes with fever, abdominal or lumbar disconfort, nocturnal pain, altered walking and sedestation. Images, culture methods and PCR (polymerase chain reaction) can be helpful for diagnosis, although in an important percent of the cases, etiology cannot be determined. Although there are no established guidelines for treatment, before the suspicion, empiric antibiotic treatment should be started for good prognosis. We describe a case of a 3 year old boy, who had this disease and then a review about spondilodiskitis in childhood and microbiological aspects of Kingella kingae.

La espondilodiscitis por Kingella kingae ha sido blanco de mayor interés en los últimos años, dado que constituye el segundo agente etiológico, luego de Staphylococcus aureus en espondilodiscitis no tuberculosa en niños. Clínicamente presenta sintomatología inespecífica, a veces acompañada de fiebre y de molestias abdominales o lumbares, con dolor de predominio nocturno y con alteraciones en la marcha y en la sedestación. El diagnóstico se puede ayudar con imágenes y métodos de cultivo o RPC (reacción polimerasa en cadena), aunque en un gran porcentaje de los casos no se logra determinar la etiología. Sin embargo, pese a que no exista un protocolo establecido para el tratamiento, ante la sospecha se debe iniciar tratamiento empírico, con buen pronóstico. Describimos un caso de un paciente de tres años que cursó con esta patología y posteriormente se expone una revisión sobre espondilodiscitis en la infancia y los aspectos microbiológicos de K. kingae.

[Respiratory infections caused by metapneumovirus in elderly patients]. / Infección respiratoria por metapneumovirus humano en pacientes adultos mayores.

Human metapneumovirus infections are increasingly recognized among adult patients and the aim of this report is to present a series of 4 cases admitted during the winter of 2010. All were detected by direct fluorescence anti-bodies assay of respiratory samples and all were female patients with an age range of 79 to 95 years, including two bedridden cases, one with dementia and three with chronic obstructive pulmonary disease. One patient presented with parainfluenza 3 virus coinfection. Patients presented with pneumonía in 3 cases (interstitial pattern in 2 and lobar consolidation in the other) or acute exacerbation of chronic bronchitis in the remaining case. Symptoms were present for 3 to 7 days before admission and 3 have wheezing. All had hypoxemic or global respiratory failure and lymphopenia (< 1.000/mm³). Hospitalization lasted for 5 to 20 days, marked in the 3 cases that survived by prolonged bronchial obstructive manifestations. Two cases required non invasive mechanical ventilation. Human metapneumovirus infections can decompensate elderly patients with chronic respiratory diseases generating hospital admission and a prolonged morbidity marked by obstructive manifestations and sometimes can become into death.

Bacteriemias e infección endovascular por Campylobacter spp: nuestra experiencia en un cuarto de siglo de historia / Bacteremia and endarteritis cases secondary to Campylobacter spp. in a metropolitan hospital: Our experience along a quarter of a century

Six cases of bacteremia and one of endarteritis were identified between 1986 and 2010 in a general hospital in Chile. Five of these cases occurred during the second half of this timeframe, Campylobacterfetus predominated (5 out of 7) and the majority of the infections presented during warmer months. The mean age was 32.4 years (range 19 to 63) all had comorbidities, and main clinical manifestations included fever with diarrhea. Four patients developed hypotension and two septic shock. The latter, associated to C. fetus bacteremia, died before microbiological diagnosis. Six out of 7 patients received antimicrobial therapy. During 2004 and 2010, the rates of Campylobacter spp. positive stool cultures in the same hospital increased 4 times, suggesting an emerging profile. Bacteremia and endarteritis by Campylobacter spp. can develop in vulnerable patients and manifest as fever with or without diarrhea. Finding curved or spiral shaped gram negative rods in blood cultures leads to suspect this pathogen. Species identification is of utmost importance due to antimicrobial resistance especially in C. jejuni. Prognosis is unfavorable due to host characteristics, and case-fatality rate is high.

Se presentan seis casos de bacteriemia y uno de infección vascular por Campylobacter spp, observados en 25 años, con el fin de describir sus características clínicas. Cinco de ellos se registraron en la segunda mitad del período, en concomitancia con el incremento de este agente en el porcentaje de coprocultivos, lo que sugiere un perfil emergente. Las infecciones fueron más frecuentes en los meses cálidos, asociadas principalmente a C. fetus (5 de 7) y a co-morbilidad. La edad promedio de los pacientes fue de 32,4 años (rango 19 a 63 años) y todos tenían comorbilidades. Las manifestaciones clínicas más frecuentes fueron diarrea y fiebre (5 de 7 casos) y dos pacientes cursaron con shock séptico (28,6 por ciento). La evolución fue favorable en cinco pacientes pero los dos que presentaron shock asociado a C. fetus fallecieron (28,6 por ciento). Las bacteriemias o infecciones vasculares por Campylobacter spp., aunque infrecuentes, pueden presentarse en pacientes vulnerables y debutar como cuadros febriles, en presencia o ausencia de diarrea. La identificación de la especie involucrada es de suma importancia debido a la escasa actividad terapéutica de cefalosporinas de tercera generación y quinolonas. El pronóstico de estas bacteriemias es grave debido a las características del hospedero y a su elevada letalidad.

Infección respiratoria por metapneumovirus humano en pacientes adultos mayores / Respiratory infections caused by metapneumovirus in elderly patients

Human metapneumovirus infections are increasingly recognized among adult patients and the aim of this report is to present a series of 4 cases admitted during the winter of 2010. All were detected by direct fluorescence anti-bodies assay of respiratory samples and all were female patients with an age range of 79 to 95 years, including two bedridden cases, one with dementia and three with chronic obstructive pulmonary disease. One patient presented with parainfluenza 3 virus coinfection. Patients presented with pneumonía in 3 cases (interstitial pattern in 2 and lobar consolidation in the other) or acute exacerbation of chronic bronchitis in the remaining case. Symptoms were present for 3 to 7 days before admission and 3 have wheezing. All had hypoxemic or global respiratory failure and lymphopenia (< 1.000/mm³). Hospitalization lasted for 5 to 20 days, marked in the 3 cases that survived by prolonged bronchial obstructive manifestations. Two cases required non invasive mechanical ventilation. Human metapneumovirus infections can decompensate elderly patients with chronic respiratory diseases generating hospital admission and a prolonged morbidity marked by obstructive manifestations and sometimes can become into death.

Las infecciones por metapneumovirus (MPVH) son poco conocidas en pacientes adultos y el objetivo de esta publicación es presentar una serie de 4 casos observados en pacientes hospitalizados durante el invierno de 2010. Los casos se identificaron por inmunofluorescencia directa en muestras respiratorias. Todos los pacientes fueron de sexo femenino con un rango de edad 79 a 95 años, dos de ellos postrados, uno con demencia y 3 con enfermedad pulmonar obstructiva crónica. La manifestación clínica correspondió a neumonía en 3 casos (2 de tipo intersticial y una con consolidación lobar) y bronquitis crónica reagudizada en el caso restante, con una duración sintomática de 3 a 7 días antes de la hospitalización. Un caso presentó co-infección con virus parainfiuenza 3. Las sibilancias estuvieron presentes en 3 casos y todos presentaron falla respiratoria hipoxémica o global con linfopenia (< 1.000/mm³). La hospitalización tuvo una duración de 5 a 20 días, marcada en los 3 casos que sobrevivieron por una signología obstructiva prolongada. Dos pacientes requirieron ventilación mecánica no invasora. Las infecciones por MPVH representan una causa de hospitalización por descompensación de patologías respiratorias crónicas en pacientes adultos ancianos, tienen una morbilidad prolongada con signología obstructiva marcada y pueden ocasionar la muerte.

[Vibrio parahaemolyticus bacteremia: case report and literature review]. / Bacteriemia por Vibrio parahaemolyticus: Reporte de caso y revisión de la literatura.

Vibrio parahaemolyticus is a facultative anaerobic gram negative rod responsible of sea food-associated diarrhoea. Although less common, it also causes wound infections and bacteraemia. We present a case of bacteraemia by this agent and a review of the literature.

[Risk factors associated to vancomycin-resistant enterococccus colonization in the Army Hospital in Santiago]. / Estudio de factores de riesgo para colonización por enterococo resistente a vancomicina en el Hospital Militar de Santiago.

Since the appearance of Vancomicin-resistant enterococci (VRE) in our country, the Chilean Ministry of Health recommended the surveillance of intestinal colonization in patients in critical wards. We report the results of surveillance in ICU and onco-hematological wards from 2002 to 2008, with analysis of possible risk factors: demographical data, use and type of antibiotic, days of hospitalization prior to sampling, and year of hospitalization. Colonization rate increased from 0.03 cases per 1000 bed-days in 2003 to 0.18 cases during 2008. Univariate analysis identified 7 risk factors associated with ERV colonization: hospitalization in ICU, use of antibiotics, use of 3 or more compounds, use of imipenem or colistin, >10 days of hospitalization prior to the study and year of hospitalization (before 2007 or after). Multivariate analysis by logistic binary regression showed that only the last two: >10 days of hospitalization prior to the study and year of hospitalization (before 2007 or after), were significantly associated to colonization by ERV.

Bacteriemia por Vibrio parahaemolyticus: reporte de caso y revisión de la literatura / Vibrio parahaemolyticus bacteremia: case report and literature review

Vibrio parahaemolyticus is a facultative anaerobio gram negative rod responsible of sea food-associated diarr-hoea. Although less common, it also causes wound infections and bacteraemia. We present a case of bacteraemia by this agent and a review of the literature.

Vibrio parahaemolyticus es un bacilo gram negativo, anaerobio facultativo, responsable de brotes de síndrome diarreico agudo por ingestión de mariscos crudos o mal cocidos contaminados. Ocasionalmente. se ha reportado asociado a infección de heridas y sepsis. Se reporta un caso clínico de bacteriemia por este microorganismo y se realiza una revisión de la literatura.

Estudio de factores de riesgo para colonización por enterococo resistente a vancomicina en el Hospital Militar de Santiago / Risk factors associated to vancomycin-resistant enterococccus colonization in the Army Hospital in Santiago

Since the appearance of Vancomicin-resistant enterococci (VRE) in our country, the Chilean Ministry of Health recommended the surveillance of intestinal colonization in patients in critical wards. We report the results of surveillance in ICU and onco-hematological wards from 2002 to 2008, with analysis of possible risk factors: demographical data, use and type of antibiotic, days of hospitalization prior to sampling, and year of hospitaliza-tion. Colonization rate increased from 0.03 cases per lOOObed-days in2003 to 0.18 cases during2008. Univariate analysis identified 7 risk factors associated with ERV colonization: hospitalization in ICU, use of antibiotics, use of 3 or more compounds, use of imipenem or colistin, > 10 days of hospitalization prior to the study and year of hospitalization ( before 2007 or after). Multivariate analysis by logistic binary regression showed that only the last two: >10 days of hospitalization prior to the study and year of hospitalization (before 2007 or after), were significantly associated to colonization by ERV.

Desde la emergencia de Enterococcus resistente a vancomicina (ERV) en Chile, el Ministerio de Salud recomendó la vigilancia de colonización intestinal por ERV en pacientes hospitalizados en unidades de pacientes críticos. Describimos los resultados de vigilancia en UCI y Unidad de Aislamiento de Pacientes Hemato-oncológicos desde 2002 a 2008, analizando probables factores de riesgo: datos demográficos, uso y tipo de antimicrobiano, días de hospitalización previo a la toma de muestra y año de hospitalización. La tasa de colonización aumentó de 0,03 casos por 1000 días cama en 2003 a 0,18 durante 2008. El análisis univariado permitió identificar siete factores asociados al riesgo de colonización por ERV: hospitalización en UCI, uso previo o actual de antimicrobianos, haber recibido tres o más antibióticos, terapia con imipenem o colistin, más de 10 días de hospitalización y el año de hospitalización. El análisis multivariado mediante regresión logística binaria, señaló la duración de la hospitalización hasta el momento del estudio (> 10 días) y el año de hospitalización (2007 o después) como factores significativamente asociados al riesgo de colonización por ERV.

[Multicenter study on the monitoring of in vitro susceptibility to tigeeyeline in Santiago, Chile]. / Estudio multicéntrico de la vigilancia de la susceptibilidad in vitro a tigeciclina en Santiago de Chile.

The objective of this multicenter study was to determine tigecycline susceptibility rates, measured by agar diffusion, in nine hospitals in Santiago and to compare these rates with other antimicrobials. Each center studied 20 strains per month. All intermediate and fully resistant strains as well as 10% of susceptibile strains were also studied by the broth microdilution method. Overall, 2301 strains were studied displaying the following susceptibility rates for tigecycline: 100% for Streptococcus sp, Enterococcus sp, and E. coli respectively, 99.8% for Staphylococcus sp, 93% for Klebsiella and 80% for Acinetobacter baumarmii. For Proteus, Providencia and Morganella the susceptibility rates were 4%. For cefotaxime-resistant Klebsiella and imipenem-resistant A. baumarmii susceptibility rates were 95% and 80% respectively. The agar diffusion and broth dilution method were 100% concordant for tigecycline susceptible strains but only 27% for resistant or intermediate strains represented mostly by Acinetobacter baumannii. The majority of these strains (57/59) proved to be susceptible after retesting. The great majority (96,6%) of strains tested from nine Chilean hospitals proved to be susceptible to tigecycline with exception for Proteus, Providencia and Morganella (66% resistance). Using the agar diffusion method for measuring tigecycline susceptibility to A. baumannii may be misleading.

Estudio multicéntrico de la vigilancia de la susceptibilidad in vitro a tigeciclina en Santiago de Chile / Multicenter study on the monitoring of in vitro susceptibility to tigeeyeline in Santiago, Chile

The objective of this multicenter study was to determine tigeeyeline susceptibility rates, measured by agar diffusion, in nine hospitals in Santiago and to compare these rates with other antimicrobials. Each center studied 20 strains per month. All intermedíate and fully resistant strains as well as 10 percent of susceptibile strains were also studied by the broth microdilution method. Overall, 2301 strains were studied displaying the foliowing susceptibility rates for tigeeyeline: 100 percent for Streptococcus sp, Enterococcus sp, and E. coli respectively, 99.8 percent for Staphylococcus sp, 93 percent for Klebsiella and 80 percent for Acinetobacter baumarmii. For Proteus, Providencia and Morganella the susceptibility rates were 4 percent. For cefotaxime-resistant Klebsiella and imipenem-resistant A. baumarmii susceptibility rates were 95 percent and 80 percent respectively. The agar diffusion and broth dilution method were 100 percent concordant for tigeeyeline susceptible strains but only 27 percent for resistant or intermedíate strains represented mostly by Acinetobacter baumannii. The majority of these strains (57/59) proved to be susceptible after retesting. The great majority (96,6 percent) of strains tested from nine Chilean hospitals proved to be susceptible to tigeeyeline with exception for Proteus, Providencia and Morganella (66 percent resistance). Using the agar diffusion method for measuring tigeeyeline susceptibility to A. baumannii may be misleading.

Para conocer la susceptibilidad a tigeciclina por difusión en agar en nueve hospitales de Santiago y comparar la susceptibilidad con otros antimicrobianos, se diseñó este estudio multicéntrico. Cada centro estudió 20 cepas mensualmente. Las intermedias, resistentes y 10 por cientoo de las susceptibles se re-testearon y estudiaron por microdilución en caldo. Se incluyeron 2.304 cepas. Fueron susceptibles a tigeciclina Strep-tococcus sp (100 por cientoo), Enterococcus sp (100 por ciento), E. coli (100 por cientoo), Staphylococcus sp (99,8 por ciento), Klebsiella pneumoniae (93 por ciento) y Acinetobacter baumannii (80 por ciento). En Proteus, Providencia y Morganella la susceptibilidad fue 4 por cientoo. Klebsiella resistente a cefotaxima y Acinetobacter resistente a imipenem, 95 por cientoo y 80 por cientoo fueron susceptibles a tigeciclina, respectivamente. La concordancia en cepas susceptibles y en las enviadas como resistentes o intermedias (A. baumannii) fue 100 por cientoo y 27 por cientoo respectivamente. El re-testeo confirmó que la mayoría eran susceptibles. Los patrones de susceptibilidad bacteriana muestran muy buena actividad in vitro a tigeciclina. La resistencia in vitro de A. baumannii por difusión en agar debe interpretarse con precaución.

Estudio de susceptibilidad a tigeciclina: Influencia del agar Mueller-Hinton en el método de difusión en agar y validación del método E-test® para Acinetobacter baumannii / In vitro evaluation of tygecicline: Influence of Mueller-Hinton agar in agar diffussion methods and validation of E-test® for Acinetobacter baumannii

Tigecycline is a glicylcicline with broad antimicrobial spectrum. Susceptibility testing to this drug for Acinetobacter is difficult in hospitals due to the utilization of the disk diffusion method. FDA break points have shown an unacceptable rate of errors (23 percent) for disk diffusion versus broth microdilution in American studies and overcall of resistance depending on the brand of Mueller Hinton agar used. Modifications to these FDA break points have been proposed, but there is not enough evidence yet. Data from a multicenter study from Chile allowed the evaluation of the characteristics of the agar used for susceptibility testing and the utility of E-test as an alternative MIC method for Acinetobacter. The Mueller Hinton agar brand is an important factor that affects disk diffusion method results. There is very good correlation between broth microdilution and E-test for the susceptibility category as well as for MIC determination. The intermedíate and resistant results obtained with disk diffusion method should be checked by using E-test.

Tigeciclina es una glicilciclina de amplio espectro antimicrobiano. La determinación de la susceptibilidad a este fármaco presenta dificultades en el laboratorio asistencial al utilizar la técnica de difusión por disco para Acinetobacter spp. Los puntos de corte -según la (FDA- han mostrado una tasa inaceptable de errores (23 por ciento) en comparación con el método de micro-dilución en caldo en estudios americanos, diversas evaluaciones demuestran que existe una sobreestimación de resistencia in vitro dependiendo de las características del agar Mueller Hinton utilizado. Se han propuesto modificaciones a los puntos de corte pero no se han oficializado por insuficientes evidencias. Los datos de un estudio multicéntrico realizado en Chile permitieron evaluar la influencia de las distintas marcas de medios de cultivo en el tamaño de los halos y la utilidad de la epsilometría (E-test®) como método CIM para Acinetobacter sp. La marca de agar Mueller Hinton y otros factores propios del medio dificultan la determinación de la susceptibilidad a tigeciclina utilizando difusión por disco. Existe muy buena correlación entre la micro-dilución en caldo y el E- test®, tanto para la categoría de susceptibilidad como para la CIM. Por esto, se sugiere que los resultados intermedios o resistentes obtenidos por difusión en agar para A. baumannii sean comprobados mediante el uso de E-test®.

[Presence of metallo beta-lactamases in imipenem-resistant Pseudomonas aeruginosa]. / Presencia de metalo-beta-lactamasas en Pseudomonas aeruginosa resistente a imipenem.

BACKGROUND: Metallo-beta-lactamases (MBL) confer high resistance to carbapenems in Pseudomonas aeruginosa (Psae). They are encoded in mobile elements of different genes (VIM, IMP, SMP, GIM), along with other resistance genes. AIM: To detect the presence of MBL in imipenem resistant Psae strains. MATERIAL AND METHODS: Fifty-nine imipenem resistant Psae strains isolated from January 2004 to August 2005 in a University Clinical Hospital, were included. The presence of MBL was studied by Etest (phenotypic) and genotypic polymerase chain reaction (PCR) methods. To rule out a nosocomial outbreak, MBL positive strains were studied by pulse field gel electrophoresis. RESULTS: The presence of MBL was detected in eleven strains. AH were type VIM and were not clonally related. There was no concordance between phenotypic and genotypic MBL detecting methods. All the strains were also multiresistant. CONCLUSIONS: The presence of MBL was detected in 19% of imipenem resistant Psae strains.

Presencia de metalo-ß-lactamasas en Pseudomonas aeruginosa resistente a imipenem / Presence of metal lo ß-lactamases in imipenem-resistant Pseudomonas aeruginosa

Background: Metallo-ß-lactamases (MBL) confer high resistance to carbapenems in Pseudomonas aeruginosa (Psae). They are encoded in mobile elements of different genes (VIM, IMP, SMP, GIM), along with other resistance genes. Aim: To detect the presence of MBL in imipenem resistant Psae strains. Material and methods: Fifty-nine imipenem resistant Psae strains isolated from January 2004 to August 2005 in a University Clinical Hospital, were included. The presence of MBL was studied by Etest (phenotypic) and genotypic polymerase chain reaction (PCR) methods. To rule out a nosocomial outbreak, MBL positive strains, were studied by pulse field gel electrophoresis. Results: The presente of MBL was detected in eleven strains. AH were type VIM and were not clonally related. There was no concordance between phenotypic and genotypic MBL detecting methods. AH the strains were also multiresistant. Conclusions: The presence of MBL was detected in 19 percent of imipenem resistant Psae strains.