Trends in Isolation and Antimicrobial Susceptibility of Enteropathogenic Bacteria in 2001-2010 at a Korean Tertiary Care Hospital / 대한임상미생물학회지

BACKGROUND: Trends in the isolation of enteropathogenic bacteria may differ depending on environmental sanitation. The aims of this study were to determine trends in the isolation and antimicrobial resistance patterns of enteropathogenic bacteria over the last 10 years. METHODS: We analyzed stool cultures of Salmonella spp., Shigella spp., Plesiomonas shigelloides, Yersinia spp., Vibrio spp., and Campylobacter spp. collected at Severance Hospital between 2001 and 2010. Antimicrobial susceptibility testing was performed using the disk diffusion method for nontyphoidal Salmonella (NTS) and Campylobacter. RESULTS: The number of specimens for stool culture significantly increased from 13,412 during 1969-1978 to 60,714 over the past 10 years, whereas the ratio of positive specimens significantly decreased from 12.9% (1,732) to 1.1% (648). The proportion of Salmonella Typhi decreased from 97.2% in 1969-1978 to 0.8% in 2001-2010, whereas the proportion of NTS increased from 2.8% to 99.2%. The proportion of Shigella among all enteric pathogens was over 50% from 1969 to 1983, while only seven strains were isolated from 2001 to 2010, with the exception of one outbreak. Campylobacter is the second most prevalent organism. The rates of susceptibility to ampicillin and cotrimoxazole were 61% and 92%, respectively, for NTS isolated from 2006 to 2010. The ciprofloxacin susceptibility rate was 79.5% for Campylobacter between 2006 and 2010. CONCLUSION: The number of isolates of Salmonella Typhi and Shigella significantly decreased, while the proportion of NTS and Campylobacter increased. Continuous monitoring of ciprofloxacin-resistant Campylobacter isolates is necessary.

Actividad bacteriostática y bactericida de la tintura de propóleos sobre bacterias enteropatógenas / Bacteriostatic and bactericidal activity of propolis tincture on enteropathogenic bacteria

El propóleos es una sustancia resinosa que las abejas Apis mellífera adultas producen para garantizar la total asepsia de la colmena. Otras especies de abejas también producen propóleos. Con el objeto de evaluar la actividad bacteriostática y bactericida in vitro de la tintura etanólica de propóleos comercial al 70 % v/v proveniente de un apiario del Estado Cojedes, Venezuela sobre bacterias enteropatógenas ATCC. Se utilizaron Salmonella entérica subsp entérica serotipo paratyphi A, Salmonella entérica subsp entérica serotipo paratyphi B Salmonella entérica subsp entérica serotipo typhi, Shigella sonnei, Shigella flexneri, Yersinia enterocolitica y Escherichia coli enterohemorrágica (O157:H7). Las cepas mencionadas se expusieron a distintas concentraciones de tintura de propóleos durante 24 horas para determinar la Concentración Mínima Inhibitoria (CMI) y la Concentración Mínima Bactericida (CMB) utilizando el método de macrodilución en tubos. Resultados: Salmonella paratyphi A fue la única bacteria con efecto inhibitorio total en agar BHI. En las demás bacterias se evidenció efecto bacteriostático parcial. Yersinia enterocolítica fue la más sensible con una CMI 4% y CMB 8 %, seguida por Shigella sonnei, Salmonella paratyphi B, Salmonella typhi y Escherichia coli (O157:H7), con CMI 8% Y CMB 11% y finalmente Shigella flexneri y Salmonella paratyphi A fueron las más resistente con CMI 11% y CMB 15%. Se demostró que la tintura de propóleos tiene efecto bacteriostático y bactericida in vitro en las cepas estudiadas y que el etanol presente como solvente no es el responsable de tal efecto.

Propolis is a resinous substance produced by adult bees Apis mellífera to ensure complete asepsis of the hive. Other species of bees also produce propolis. The aim of this study was to assess the bacteriostatic and bactericidal activity in vitro of commercial ethanolic tincture of propolis 70% v/v from an apiary in Cojedes State, Venezuela on enteropathogenic bacteria ATCC. Used Salmonella enterica subsp enterica suptype paratyphi A, Salmonella enterica subsp enterica suptype paratyphi B, Salmonella enterica subsp enterica subtype typhi, Shigella sonnei, Shigella flexneri, Yersínia enterocolitica, and Escherichia coli (O157:H7). The strains mentioned were exposed to different concentrations of propolis for 24 hours to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) using the macrodilution method in tubes. Results: S. paratyphi A was the only bacterium with a total inhibitory effect on agar BHI. In other bacteria, a partial bacteriostatic effect was observed. Y. enterocolítica was the most sensitive with a CMI 4% and CMB 8 %, followed by E. coli (O157:H7). S. typhi, S. paratyphi B and S. sonnei with CMI 8% and CMB 11% and finally S. flexneri and S. paratyphi A were the most resistant with CMI 11% and CMB 15%. Results indicate that propolis tincture has a bacteriostatic and bactericidal effect in vitro in the strains studied, and that such effect is not due to the ethanol present as solvent.

Enteropathogenic Bacteria Contamination of Unchlorinated Drinking Water in Korea, 2010

OBJECTIVES: The purpose of this study was to assess the microbiological quality of unchlorinated drinking water in Korea, 2010. One hundred and eighty unchlorinated drinking water samples were collected from various sites in Seoul and Gyeonggi province. METHODS: To investigate bacterial presence, the pour plate method was used with cultures grown on selective media for total bacteria, total coliforms, and Staphylococcus spp., respectively. RESULTS: In the 180 total bacteria investigation, 72 samples from Seoul and 33 samples from Gyeonggi province were of an unacceptable quality (>10(2) CFU/mL). Of all the samples tested, total coliforms were detected in 28 samples (15.6%) and Staphylococcus spp. in 12 samples (6.7%). Most of the coliform isolates exhibited high-level resistance to cefazolin (88.2%), cefonicid (64.7%) and ceftazidime (20.6%). In addition, Staphylococcus spp. isolates exhibited high-level resistance to mupirocin (42%). Species of Pseudomonas, Acinetobacter, Cupriavidus, Hafnia, Rahnella, Serratia, and Yersinia were isolated from the water samples. CONCLUSIONS: The results of this study suggest that consumption of unchlorinated drinking water could represent a notable risk to the health of consumers. As such, there is need for continuous monitoring of these water sources and to establish standards.

Calidad microbiológica y bacterias enteropatógenas en vegetales tipo hoja / Microbiological quality and enteropathogenic bacteria in leaf vegetables

Para analizar la calidad microbiológica en vegetales tipo hoja y la incidencia de bacterias enteropatógenas se analizaron 150 muestras (50 lechugas, 50 cilantros y 50 perejiles) recolectadas en dos supermercados de Maracaibo. Se determinó Coliformes Totales (CT) y Escherichia coli (EC) según la norma COVENIN Nº3276:1997; para la determinación de bacterias enteropatógenas (Salmonella, Aeromonas y Vibrio) se utilizaron medios de enriquecimiento y selectivos. La identificación de especies se realizó empleando pruebas bioquímicas. En 81,33% (122/150) de las muestras se obtuvieron contajes de CT entre 10³-10 5 UFC/g. La recuperación de EC fue de 10,00%. La frecuencia de enteropatógenos fue de 28%, siendo Aeromonas el género más aislado con un 95,91%. La mayor recuperación de enteropatógenos se obtuvo en las muestras de cilantro (40,00%), seguida de perejil (34,00%) y lechuga (20,00%); A. caviae fue la especie más recuperada (59,18%) seguida de A. hydrophila (30,62%). Salmonella spp se recuperó en 2 (4,08%) muestras. La presencia de indicadores entéricos (CT y EC) y de bacterias enteropatógenas sugiere que los vegetales tipo hoja presentan una inadecuada calidad sanitaria y pueden ser fuente de gastroenteritis

To analyze the microbiological quality of leaf vegetables and the incidence of enteropathogenic bacteria, 150 samples (50 lettuce, 50 coriander and 50 parsley) collected in two supermarkets in Maracaibo, were studied. Total coliforms (TC) and Escherichia coli (EC) according to COVENIN guideline N° 3276: 1997, were determined; for the identification of enteropathogenic bacteria (Salmonella, Aeromonas, Vibrio), enrichment and selective media were used. Species identification was made using biochemical tests. In 81.33% (122/150) of the samples obtained, TC counts were between 10³-10 5 CFU/g. EC recovery was 10.00%. The frequency of enteropathogens was 28%, with Aeromonas the most isolated genus (95.91%). Greater recovery of enteropathogens was obtained from coriander (40.00%), followed by the parsley (34.00%) and lettuce samples (20.00%); A. caviae was the most recovered specie (59.18%) followed by A. hydrophila (30,62%). Salmonella spp were recovered in 2 samples (4.08%). The presence of enteric indicators (TC and EC) and enteropathogenic bacteria suggests that the sanitary condition of the leafy vegetables is inadequate and can be a source of gastroenteritis

Calidad microbiológica en frutas de conchas comestibles expendidas en mercados populares de los municipios Valencia y San Diego, estado Carabobo, Venezuela / Microbiological quality of fruits that have edible peels sold at popular markets of the Valencia and San Diego Municipalities, Carabobo State, Venezuela

Las frutas constituyen un grupo de nutrientes indispensables para la salud y bienestar del individuo. Se evaluó la calidad microbiológica en frutas de concha comestible (fresas, guayabas y duraznos) expendidas en mercados populares de Valencia y San Diego, estado Carabobo, Venezuela. Se determinó el número de UFC/g de mesófilos aerobios (MA), coliformes totales y fecales (CT, CF) y Salmonella spp. según Normas COVENIN. La mayoría de los recuentos obtenidos de MA fueron elevados en la mayoría de las frutas. Los niveles de contaminación por estos microorganismos se encontraron entre 1,4x10(5) y 6,6x10(10) UFC/g. Los recuentos encontrados para CT generalmente resultaron inferiores a los obtenidos para los MA, y se encontraron en un rango de 2,6x10³ a 7,2 x 10(10) UFC/g. No se detectó la presencia de CF y de Salmonella spp., en las muestras evaluadas. De las frutas analizadas las fresas fueron las que presentaron el mayor grado de contaminación microbiológica tanto por MA como CT. La ausencia de CF y Salmonella spp. sugiere que las condiciones a las cuales fueron sometidas las frutas durante el período de pre y postcosecha, estuvieron aparentemente dentro los límites permisibles de calidad sanitaria.

Fruits constitute a group of indispensable nutrients for the health and wellbeing of individuals. We evaluated the microbiological quality of fruits with edible peels (strawberries, guavas and peaches) sold at popular markets in Valencia and San Diego, Carabobo State, Venezuela. We determined the number of CFU/g of mesophilic aerobics (MA), total and fecal coliforms (TC, FC) and Salmonella spp. according to COVENIN guidelines. Most of the MA counts obtained were high in most fruits. The contamination levels by these microorganisms were found to be between 1.4x10(5) and 6.6x10(10) CFU/g. The counts found for TC were generally lower than those for MA, and occurred in amounts of between 2.6x10³ and 7.2x10(10) CFU/g. The presence of FC and Salmonella spp. was not detected in the samples evaluated. Of the fruits studied, strawberries were the ones which showed the highest microbiological contamination degree both by MA and TC. The absence of TC and Salmonella spp. suggests that the conditions to which the fruits were submitted during the pre and post harvest period apparently were within the permissible limits of sanitary quality.

Effects of enteropathogenic bacteria & lactobacilli on chemokine secretion & Toll like receptor gene expression in two human colonic epithelial cell lines.

Background & objectives: The intestinal epithelium is part of the innate immune system responding to contact with pathogenic or commensal bacteria. The objective of this study was to compare innate responses of intestinal epithelial cell lines to pathogenic bacteria and to lactobacilli. Methods: Two human intestinal epithelial cell lines, HT29 (enterocyte-like) and T84 (crypt-like), were exposed to pathogenic bacteria representative of non invasive (Vibrio cholerae O1 and O139), adherent (enterohaemorrhagic Escherichia coli, EHEC) or invasive (Salmonella Typhimurium and Shigella flexneri) phenotypes and to non pathogenic Lactobacillus rhamnosus GG or Lactobacillus plantarum. Interleukin-8 (IL-8) was measured in culture supernatant by ELISA, while mRNA from cells was subjected to quantitative reverse transcriptase PCR for several other chemokines (CXCL1, CCL5 and CXCL5) and for Toll-like receptors (TLR) 2, 4, 5 and 9. Results: V. cholerae, S. Typhimurium, S. flexneri and EHEC induced IL-8 secretion from epithelial cells into the medium. Salmonella, Shigella and EHEC, but not V. cholerae, significantly increased mRNA expression of CXCL1. None of the pathogens induced CCL5 or CXCL5. Salmonella and Vibrio significantly increased TLR4 expression, while Vibrio and EHEC decreased TLR5 expression. EHEC also decreased TLR9 expression. Lactobacilli attenuated the IL-8 response of the cell lines to V. cholerae, Salmonella, and EHEC but did not significantly change the IL-8 response to Shigella. Interpretation & conclusions: Distinct patterns of epithelial cell chemokine responses were induced by the bacterial pathogens studied and these were modulated by commensal lactobacilli. Alterations in TLR expression by these pathogens are likely to be important in pathogenesis.

Isolation Trend of Enteropathogenic Bacteria in 1969-1998 / 대한임상미생물학회지

BACKGROUND: Diarrheal disease has been one of the most common health problem in Korea with Salmonella and Shigella being the major bacterial pathogens. Prevalence of enteric bacterial pathogens may differ significantly depending on the socioeconomic status of a country. Therefore, rapid improvement of living conditions in Korea should have profound effect on the incidence of enteric infection. In some Salmonella infections, proper antimicrobial treatment is important to reduce morbidity and mortality, but rapid change of the susceptibility makes the susceptibility unpredictable. So, there is a need to describe the change of antimicrobial susceptibility of Salmonella. METHODS: In this study, stool culture results at Severance Hospital during the years 1969-1998 were analyzed to determine the trends of enteric bacterial isolation and the susceptibility of the isolates. RESULTS: The proportion of S. typhi was reduced to 1.4% in 1994-1998. The proportion of Shigella was over 50% of all enteric pathogens until 1983, while only 14 strains were isolated during the last 5 years. Campylobacter spp. became the second most prevalent organism with the decrease of Shigella isolation. Ampicillin- and cotrimoxazole-susceptible nontyphoidal Salmonella gradually decreased to 76% and 90%, respectively in 1994-1998 and even several extended-spectrum beta- lactamase-producing strains were detected. Strains of ampicillin-resistant S. typhi were first detected in 1995. CONCLUSIONS: Typhoid fever and shigellosis are rare disease now in urban clinical setting while nontyphoidal Salmonella infection is a prevalent one. Campylobacter is the second most common enteric bacterial pathogen. With the increase of antimicrobial resistance of nontyphoidal Salmonella and appearance of resistant S. typhi, difficulties in the treatment of these infections may be expected in the future.

Isolamento de bactérias enteropatogênicas de coproculturas realizadas durante o período 1977-1983 na Seção de Bacteriologia do Instituto Adolfo Lutz, São Paulo / Isolation of enteropathogenic bacteria from stool cultures performed during the period 1977-1983 at the Bacteriology Section of Instituto Adolfo Lutz, São Paulo

Durante o período compreendido entre 1977 e 1983 foram realizadas 19.284 coproculturas na Seção de Bacteriologia do Instituto Adolfo Lutz. A positividade foi de 31,850/0, onde 15,890/0 pertencia à Salmonella, 12,130/0 à Escherichia coli enteropatogênica, enteroinvasiva e enterotoxigênica, e 3,830/0 à Shigella. Em 11,070/0 dos exames positivos foi isolada mais de uma enterobactéria patogênica em uma mesma amostra. S. typhimurium e S. agona foram os sorotipos mais freqüentes, correspondendo a 89,950/0 do total das salmonelas isoladas. Os sorogrupos de E. coli enteropatogênica de maior incidência foram 0111 e 0119. Entre as E. coli enteroinvasivas, os sorogrupos mais frequentes foram 028ac, 0124 e 0136. Mais de 500/0 das cepas de E. coli enterotoxigênica pertencia ao sorogrupo 0128, e as cepas enterotoxigênicas portadoras dos fatores de colonização CFAjI ou CFAjII correspondiam a aproximadamente 350/0 do total. Assemelhando-se à incidência em outros países, mais de 95% das cepas de Shigella pertencia à Shigella flexneri e à Shigella sonnei. Salmonella, Shigella e E. coli representam, ainda, os principais agentes etiológicos em nosso meio. Durante o período de um ano não foi isolada nenhuma cepa de Yersinia enterocolitica. ° isolamento de Campylobacte.· jejuni, nos dois últimos anos de pesquisa realizada na Seção de Bacteriologia (AU).