Colonización rectal por bacilos gram negativos multirresistentes: importancia de la detección precoz durante la hospitalización / Rectal colonisation by multiresistant gram-negative bacilli: relevance of early detection in the course of hospitalization / Colonização retal por bacilos gram negativos multirresistentes: importância da identificação precoce durante a hospitalização

Las infecciones asociadas con el cuidado de la salud son consideradas un problema epidémico, controlable pero difícilmente erradicable. La detección precoz de pacientes colonizados por microorganismos multirresistentes, a través de cultivos de vigilancia epidemiológica y la implementación de medidas preventivas pueden reducir su incidencia. El objetivo del trabajo fue establecer los momentos adecuados durante la hospitalización para realizar estudios de colonización y decidir los microorganismos a estudiar según el lugar de procedencia del paciente. Se analizaron hisopados rectales de pacientes internados en la Unidad de Terapia Intensiva, obtenidos al ingreso, a las 72 h y al sexto día de internación. Se investigó Acinetobacter spp multirresistente (AMR), enterobacterias productoras de BLEE (EB-BLEE) y de KPC (EB-KPC). Los resultados mostraron 15,2% de pacientes de la comunidad y 16,7% de geriátricos colonizados con EB-BLEE al ingreso. Dicho porcentaje fue mayor (28,6%) en pacientes previamente institucionalizados y, además, 2,6% colonizados con EB-KPC y 3,4% con AMR. Los controles posteriores mostraron porcentajes crecientes de portación con el transcurso de la internación. Por lo tanto, es importante la detección de estos microorganismos al ingreso hospitalario y continuar con vigilancia activa, para poder implementar medidas precoces tendientes a evitar las consecuencias de la rápida transmisión horizontal.

Healthcare associated infections are considered an epidemic problem; manageable but difficult to eradicate. The early detection of patients infected with antimicrobial multiresistant microorganisms by means of epidemiological surveillance cultures and the execution of prophylactic measures, are key to reduce their incidence. The aim of this work was to assess a suitable schedule in the course of hospitalisation to perform colonisation studies and to decide which microorganisms to analyse according to the provenance of the patient. Rectal swabs from patients admitted at the Intensive Care Unit obtained at the time of admission, 72 h and six days later were analysed. Multiresistant Acinetobacter spp.(MRA), ESBL- and KPC- producing Enterobacteriaceae (ESBL-EB and KPC-EB, respectively) were investigated. Results showed that 15.2% of patients without previous hospitalisation and 16.7% of patients coming from geriatric institutions were colonised by ESBL-EB at the moment of admission. This percentage was greater (28.6%) in previously hospitalised patients, of whom 2.6% were found to be colonized by KPC-EB and 3.4% by MRA. Subsequent monitoring showed increasing colonisation percentages with the course of hospitalisation. Therefore, detection of these microorganisms at the time of admission and constant active surveillance are crucial to implement early measures aiming to avoid the consequences of rapid horizontal dissemination.

As infecções relacionadas ao cuidado da saúde são consideradas um problema epidêmico controlável, mas dificilmente erradicável. A identificação precoce em pacientes colonizados por microorganismos multirresistentes, através de culturas de vigilância epidemiológica e a implementação de medidas preventivas, podem diminuir sua incidência. O objetivo do trabalho foi estabelecer os momentos adequados durante a hospitalização para realizar testes de colonização e decidir quais os microorganismos que serão estudados de acordo com o lugar de procedência do paciente. Foram testados Swabs retais de pacientes internados na Unidade de Terapia Intensiva (UTI), coletados ao serem admitidos, nas 72h e no sexto dia de internação. Foram analisados Acinetobacter spp. multirresistente (AMR), enterobactérias produtoras de BLEE (EB-BLEE) e de KPC (EB-KPC). Os resultados mostraram 15.2% de pacientes da comunidade e 16.7% de geriátricos colonizados com EB-BLEE ao serem admitidos. Ese percentual foi maior (28.6%) em pacientes previamente institucionalizados e, além disso, 2.6% colonizados com EB-KPC e 3.4% com AMR. Os controles posteriores mostraram percentuais crescentes de portação com o decorrer da internação. Portanto, é importante a identificação destes microorganismos no momento da admissão hospitalar e continuar com a vigilância ativa, para poder implementar medidas precoces tendentes a evitar as consequências da rápida transmissão horizontal.

Ex vivo model of rabbit intestinal epithelium applied to the study of colonization by enteroaggregative escherichia coli / Modelo ex vivo de epitélio intestinal de coelho aplicado ao estudo de colonização por Escherichia coli enteroagregativa

ABSTRACT BACKGROUND The diarrheal syndrome is considered a serious public health problem all over the world and is considered a major cause of morbidity and mortality in developing countries. The high incidence of enteroaggregative Escherichia coli in diarrheal syndromes classified as an emerging pathogen of gastrointestinal infections. After decades of study, your pathogenesis remains uncertain and has been investigated mainly using in vitro models of adhesion in cellular lines. OBJECTIVE The present study investigated the interaction of enteroaggregative Escherichia coli strains isolated from childhood diarrhea with rabbit ileal and colonic mucosa ex vivo, using the in vitro organ culture model. METHODS The in vitro adhesion assays using cultured tissue were performed with the strains co-incubated with intestinal fragments of ileum and colon over a period of 6 hours. Each strain was tested with three intestinal fragments for each region. The fragments were analysed by scanning electron microscopy. RESULTS Through scanning electron microscopy we observed that all strains adhered to rabbit ileal and colonic mucosa, with the typical aggregative adherence pattern of “stacked bricks” on the epithelium. However, the highest degree of adherence was observed on colonic mucosa. Threadlike structures were found in greater numbers in the ileum compared to the colon. CONCLUSION These data showed that enteroaggregative Escherichia coli may have a high tropism for the human colon, which was ratified by the higher degree of adherence on the rabbit colonic mucosa. Finally, data indicated that in vitro organ culture of intestinal mucosa from rabbit may be used to elucidate the enteroaggregative Escherichia coli pathogenesis.

RESUMO CONTEXTO A síndrome diarréica é considerada um grave problema de saúde pública em todo o mundo e é considerada uma das principais causas de morbidade e mortalidade nos países em desenvolvimento. A elevada incidência de Escherichia coli enteroagregativa nas síndromes diarreicas a classificou como um patógeno emergente de infecções gastrintestinais. Depois de décadas de estudo, sua patogênese ainda é incerta e tem sido investigada usando principalmente modelos in vitro de adesão em linhagens celulares. OBJETIVO O presente estudo investigou a interação de cepas de Escherichia coli enteroagregativa isoladas de diarreia infantil com mucosa ileal e colônica de coelho ex vivo, utilizando o modelo de cultura de órgão in vitro. MÉTODOS Os ensaios de adesão in vitro utilizando tecido cultivado foram realizados com as cepas co-incubadas com fragmentos intestinais de íleo e de cólon durante um período de 6 horas. Cada cepa foi testada em três fragmentos intestinais para cada região. Os fragmentos foram analisados por microscopia eletrônica de varredura. RESULTADOS Através da microscopia eletrônica de varredura observamos que todas as cepas aderiram a mucosa ileal e colônica de coelho, com o padrão de aderência agregativo típico de “tijolos empilhados” no epitélio. Entretanto, o maior grau de adesão foi observado na mucosa do cólon. Estruturas filiformes foram encontradas em maior número no íleo em comparação com o cólon. CONCLUSÃO Esses dados mostraram que Escherichia coli enteroagregativa pode ter um maior tropismo para o cólon humano, o que foi ratificado pelo maior grau de aderência na mucosa do cólon de coelho. Finalmente, os dados indicaram que a cultura de órgão in vitro da mucosa intestinal de coelho pode ser utilizado para elucidar a patogênese de Escherichia coli enteroagregativa.

Paracoccidioidomicosis colónica en un hospital de Lima - Perú: reporte de 4 casos / Colon Paracoccidioidomycosis in a hospital from Lima - Peru: report of 4 cases

La paracoccidioidomicosis es la micosis más prevalente de Sudamérica. En nuestro medio la afectación mucocutánea y linfática suele ser la de mayor prevalencia, siendo el compromiso intestinal pocas veces reportado. Se reportan 4 casos de afectación colónica con manifestación de dolor abdominal, diarrea crónica y disminución de peso en los cuales el diagnóstico se realizó a través de la anatomía patológica con la tinción de Gomori. La edad promedio fue de 29 años. La colonoscopía reveló presencia de múltiples úlceras en colon y en íleon distal. Como comorbilidad se encontró VIH en un paciente

Paracoccidioidomycosis is the most prevalent mycosis in South America. Mucocutaneous and lymph node involvement is the most frequent affectation of this disease in our country, with the intestinal commitment rarely reported. We report 4 cases of colonic manifestation with abdominal pain, chronic diarrhea, and weight loss. The diagnosis was made with biopsy and Gomori stain. The average age was 29 years old. The colonoscopy showed many ulcers in the ileum distal and colon. We found VIH as comorbidity in one patient

Changes in clinical signs after treatment in calves with experimental colisepticemia with Escherichia coli

Background: Colisepticemia is an acute fatal disease in farm animal neonates. Clinical finding of septicemia is non-specific and cannot be differentiated from signs of non-infectious disease or disease with local infection such as diarrhea

Objectives: Evaluation of clinical signs variations in calves with experimental septicemia with Escherichia coli 01 11 :H8

Methods: Colisepticemia was experimentally induced in ten Holstein bull calves after an adaptation period. Vital signs and 7 clinical criteria were recorded from 24 h before septicemia until 48 h after that. Blood culture was performed and treatment was done based on antibiogram from 24 h after challenge

Results: Changes of suckling reflex and shock were not significant. Changes of appetite, dehydration, behavior, standing ability, total score from 24 h before the challenge to 24 h after treatment were significant [p=0.00l]. Fecal consistency altered with treatment [p<0.04]. Heart rate [p=0.04 and p=0.033, respectively], respiratory rate [p=0.009 and p=0.001, respectively] and body temperature [p0.00l and p=0.004, respectively] have significant changes till 24 h after challenge and till 24 h after starting treatment. Blood cultures were positive except for 0 h and 48 h after challenge

Conclusions: The present study indicated clinical signs changed unfavorably following septicemia that were dissolved approximately during 24 h, depending on treatment in appropriate time and drug choice. Thus, a targeted scoring system will be useful in clinical evaluation of septicemia, quantifying the changes procedure and treatment efficacy

Fusobacterium Isolates Recovered From Colonic Biopsies of Inflammatory Bowel Disease Patients in Korea

No abstract available.

Invasive Primary Colonic Aspergillosis in the Immunocompetent Host without Classical Risk Factors

Invasive aspergillosis (IA), generally considered an opportunistic infection in immunocompromised hosts, is associated with high morbidity and mortality. IA commonly occurs in the respiratory tract with isolated reports of aspergillosis infection in the nasal sinuses, central nervous system, skin, liver, and urinary tract. Extra-pulmonary aspergillosis is usually observed in disseminated disease. To date, there are a few studies regarding primary and disseminated gastrointestinal (GI) aspergillosis in immunocompromised hosts. Only a few cases of primary GI aspergillosis in non-immunocompromised hosts have been reported; of these, almost all of them involved the upper GI tract. We describe a very rare case of IA involving the lower GI tract in the patient without classical risk factors that presented as multiple colon perforations and was successfully treated by surgery and antifungal treatment. We also review related literature and discuss the characteristics and risk factors of IA in the immunocompetent hosts without classical risk factors. This case that shows IA should be considered in critically ill patients, and that primary lower GI aspergillosis may also occur in the immunocompetent hosts without classical risk factors.

Relationship between the Severity of Diversion Colitis and the Composition of Colonic Bacteria: A Prospective Study

BACKGROUND/AIMS: Diversion colitis is the inflammation of the excluded segment of the colon in patients undergoing ostomy. It has been suggested that a change in colonic flora may lead to colitis; however, direct evidence for this disease progression is lacking. The aim of this study was to evaluate the relationship between the severity of diversion colitis and the composition of colonic bacteria. METHODS: We used culture methods and polymerase chain reaction to analyze the colonic microflora of patients who underwent rectal cancer resection with or without diversion ileostomy. In the diversion group, we also evaluated the severity of colonoscopic and pathologic colitis before reversal. RESULTS: This study enrolled 48 patients: 26 in the diversion group and 22 in the control group. Significant differences were observed between the two groups in the levels of Staphylococcus (p=0.038), Enterococcus (p<0.001), Klebsiella (p<0.001), Pseudomonas (p=0.015), Lactobacillus (p=0.038), presence of anaerobes (p=0.019), and Bifidobacterium (p<0.001). A significant correlation between the severity of colitis and bacterial composition was only observed for Bifidobacterium (p=0.005, correlation coefficient=-0.531). CONCLUSIONS: The colonic microflora differed significantly between the diversion and control groups. Bifidobacterium was negatively correlated with the severity of diversion colitis.

Adherent Escherichia coli in colorectal mucosal biopsies: A histological and ultrastructural evaluation.

Background: Colorectal mucosal biopsies occasionally demonstrate the presence of bacteria adherent to the epithelium. This study evaluated the histological and ultrastructural correlates of such bacterial adherence. Materials and Methods: Rectal mucosal biopsies from eight patients in whom histopathological examination of biopsies had earlier demonstrated adherent bacteria were examined by electron microscopy and by bacterial culture. Colorectal biopsies of 69 patients with adherent bacteria detected histologically were retrospectively evaluated for histological changes at sites proximal and distant to adherent bacteria. Results: Escherichia coli of different serogroups were isolated from 7 of 8 rectal biopsies demonstrating bacterial adherence. All isolates showed diffuse or focal adherence to HEp-2 cell monolayers. Ultrastructural changes noted included microvillus damage, pedestal formation, actin web condensation, and protrusions of the apical cytoplasm of epithelial cells into the lumen towards the bacteria. Histological changes noted at light microscopy included reduction in epithelial cell height, focal epithelial cell degeneration, cryptitis and neutrophil infiltration at sites of bacterial adherence whereas these were usually absent at sites distant to adherent bacteria. Bacterial adherence was noted more often in biopsies from Crohn's disease patients than in patients without this diagnosis (P < 0.001). Conclusion: Adherent Escherichia coli in colorectal biopsies were associated with focal epithelial damage and showed an association with Crohn's disease.

Adherence of enteroaggregative Escherichia coli to the ileal and colonic mucosa: an in vitro study utilizing the scanning electron microscopy / Aderência da Escherichia coli enteroagregativa a mucosas ileal e colônica: estudo in vitro utilizando microscopia eletrônica de varredura

CONTEXT: Enteroaggregative Escherichia coli strains have been associated with persistent diarrhea in several developing countries. In vivo procedures with animal models, in vitro assays with cellular lines and in vitro organ culture with intestinal fragments have been utilized to study these bacteria and their pathogenicity. OBJECTIVE: The present experimental research assessed the pathogenic interactions of three enteroaggregative Escherichia coli strains, using the in vitro organ culture, in order to show the adherence to different regions of both, the ileal and the colonic mucosa and demonstrate possible mechanisms that could have the participation in the prolongation of diarrheiogenic process. METHODS: This study used intestinal fragments from terminal ileum and colon that were excised from pediatric patients undergoing intestinal surgeries and from adult patients that underwent to colonoscopic procedures. Each strain was tested with three intestinal fragments for each region. Tissue was fixed for scanning electron microscopic analysis. RESULTS: These bacteria colonized ileal and colonic mucosa in the typical stacked-brick configuration in the ileum and colon. In both regions, the strains were seen over a great amount of mucus and sometimes over the intact epithelium. In some regions, there is a probable evidence of effacement of the microvilli. It was possible to see adhered to the intestinal surface, bacteria fimbrial structures that could be responsible for the adherence process. CONCLUSION: In order to cause diarrhea, enteroaggregative Escherichia coli strains adhere to the intestinal mucosa, create a mucoid biofilm on the small bowel surface that could justify the digestive-absorptive abnormalities and consequently, prolonging the diarrhea.

CONTEXTO: Cepas de Escherichia coli enteroagregativa têm sido associadas à diarreia persistente em vários países em desenvolvimento. Procedimentos in vivo com modelos animais, cultura de órgão in vitro com fragmentos intestinais e ensaios in vitro com linhas celulares têm sido utilizados para estudar essas bactérias e a sua patogenicidade. OBJETIVO: A presente investigação experimental avaliou as interações patogênicas de três cepas de Escherichia coli enteroagregativa, usando cultura de órgão in vitro, para mostrar a aderência a diferentes regiões do intestino: íleo e cólons e demonstrar possíveis mecanismos que poderiam ter participação na perpetuação do processo diarréico. MÉTODOS: Este estudo usou fragmentos de íleo terminal e cólon que foram retirados de pacientes pediátricos submetidos a cirurgias intestinais e de pacientes adultos que foram submetidos a colonoscopias. Cada cepa foi testada com três fragmentos intestinais para cada região. O tecido foi fixado para análise sob microscopia eletrônica de varredura. RESULTADOS: Estas bactérias colonizaram mucosa ileal e colônica na configuração típica de pilhas de tijolos. Em ambas as regiões, as bactérias foram vistas sobre grande quantidade de muco e, às vezes, sobre o epitélio intacto. Em algumas áreas, há evidência de provável achatamento de vilosidades. Foi possível ver sobre a superfície intestinal, estruturas fimbriais bacterianas que poderiam estar relacionadas ao processo de adesão. CONCLUSÕES: Para causar diarreia, cepas de Escherichia coli enteroagregativa aderem à mucosa intestinal e criam um biofilme de muco sobre a superfície do intestino delgado, o que poderia justificar as anormalidades digestivo-absortivas e, por conseguinte, prolongar a diarreia.

Effect of Lactobacillus acidophilus & epidermal growth factor on experimentally induced Clostridium difficile infection.

Background & objectives: Clostridium difficile-associated disease (CDAD) remains an important nosocomial ailment. Antimicrobial therapy used for CDAD gives inconsistent results. This experimental study was planned to investigate the beneficial effects of Lactobacillus acidophilus and epidermal growth factor (EGF) for CDAD management. Methods: Among 10 groups of BALB/c mice (6 in each), group 1 served as controls receiving no inoculum. Animals in groups 2-10 received C. difficile, those in groups 3, 6 and 9 received L. acidophilus and those in groups 4, 7 and 10 received EGF after C. difficile inoculation. Animals in groups 5-7 were pre-treated with ampicillin and those in groups 8-10 with lansoprazole prior to C. difficile. The animals were killed and investigated for colonisation by C. difficile and toxin production, myeloperoxidase (MPO) activity and histopathology. Results: Colonisation by C. difficile was found to be significantly different (P<0.001) in the various groups. C. difficile toxin titres and MPO activity were significantly lower in animals given L. acidophilus and EGF after ampicillin (groups 6 and 7) and lansoprazole (groups 9 and 10). The severity of acute inflammation was also significantly less (P<0.05) in caecal and colonic segments of animals in groups 6 and 7 compared to those in group 5. Although the severity of acute inflammation was less in the caecal and colonic segment of animals in groups 9 and 10, the reduction was not significant compared to group 8. Interpretation & conclusions: Our findings showed that the administration of L. acidophilus and EGF reduced the severity of C. difficile infection in the experimental animals.

Pathophysiology of enteroaggregative Escherichia coli infection: an experimental model utilizing transmission electron microscopy / Fisiopatologia da infecção pela Escherichia coli enteroagregativa: um modelo experimental utilizando microscopia eletrônica de transmissão

CONTEXT: Enteroaggregative Escherichia coli strains have been associated with persistent diarrhea in several developing countries. In vivo procedures with animal models as rat, rabbit and gnotobiotic piglets intestinal loops, in vitro assays with cellular lines like T84, Caco 2, HT29, HeLa e HEp-2 and in vitro organ culture with intestinal fragments have been applied to study these bacteria and their pathogenicity. OBJECTIVES: The present experimental research assessed the pathogenic interactions of three enteroaggregative Escherichia coli strains, using the in vitro organ culture, in order to observe and compare alterations in different regions of both, the ileal and the colonic mucosa. METHODS: This study applied intestinal fragments from terminal ileum and colon that were excised from pediatric and adult patients that underwent colonoscopic procedures. Tissue was fixed for transmission electron microscopic study. Each bacterium was tested with three intestinal fragments for each region. RESULTS: Enteroaggregative Escherichia coli strains colonized and provoked citotoxic effects in the ileal and colonic mucosa. Total or partial villi destruction, vacuolization of basal cytoplasm of the enterocytes, epithelium detachment, derangement of the structure and epithelial cell extrusion in ileal mucosa could explain the perpetuation of the diarrhea. Bacterial aggregates were seen in intestinal lumen associated with mucus and cellular debris and in the intercellular spaces of the destroyed epithelium, suggesting bacterial invasion that seemed to be secondary to the destruction of the tissue. CONCLUSIONS: Pathogenesis of persistent diarrhea should include alterations in the small bowel structures where the digestive-absorptive functions take place. In the colonic mucosa the inflammatory lesions could explain the occurrence of colitis.

CONTEXTO: A Escherichia coli enteroagregativa está associada à diarréia persistente em vários países em desenvolvimento. Procedimentos in vivo empregando modelos animais como ratos, coelhos e alças intestinais de suínos gnotobióticos, e modelos in vitro com linhas celulares, tais como: T84, Caco 2, HT29, HeLa e HEp-2 e cultura de órgão in vitro são empregados no estudo desta bactéria e de sua patogenicidade. OBJETIVOS: Neste trabalho foram avaliadas as interações de três cepas de Escherichia coli enteroagregativa usando cultura de órgão in vitro, com o objetivo de observar e comparar as alterações em diferentes regiões do intestino: mucosa ileal e mucosa colônica. MÉTODOS: Este estudo empregou fragmentos de íleo terminal e cólon extraídos de pacientes submetidos a colonoscopia. Os fragmentos intestinais infectados in vitro foram fixados para avaliação em microscopia eletrônica de transmissão. Cada cepa bacteriana foi testada com três fragmentos intestinais de cada região. RESULTADOS: As cepas estudadas colonizaram e provocaram efeitos citotóxicos no íleo e no cólon. Alterações na mucosa ileal, tais como: destruição parcial ou total das vilosidades, vacuolização do citoplasma basal dos enterócitos, destacamento do epitélio e desarranjo da estrutura com extrusão de células epiteliais poderiam explicar a perpetuação do processo diarréico. Agregados bacterianos foram vistos no lúmen intestinal associados a muco e restos celulares e nos espaços intercelulares do epitélio destruído sugerindo invasão bacteriana que pareceu ser secundária à destruição do tecido. CONCLUSÃO: A patogênese da diarréia persistente deve incluir alterações no intestino delgado aonde ocorrem as funções digestivo-absortivas. Na mucosa colônica as lesões inflamatórias observadas justificariam a ocorrência de colite.

Motilidad intestinal y microflora / Intestinal motility and microflora

La microflora es el conjunto de colonias microbacterianas que cubren la superficie del tubo digestivo. Cada sujeto humano alberga unos 100 billones de colonias de unas 400 especies distintas, biodiversidad que facilita la vida y el desarrollo del conjunto. La concentración de bacterias va aumentando a lo largo del tubo digestivo, alcanzando concentraciones de 1012 UFC/ml. en el colon. La motilidad del intestino delgado es propulsiva con una fase de barrido que no permite el crecimiento de bacterias. Por el contrario, la motilidad del colon es muy lenta y no propulsiva durante el ayuno y el sueño. Sólo en vigilia y en período postprandial existen ondas de contracción de alta amplitud y rápidamente progresivas en dirección oral-anal. La interacción entre las bacterias presentes en el lumen y las ondas de contracción motora es muy difícil de evaluar. Este efecto se ha estudiado en base a los fármacos que alteran la motilidad y que al aumentar ésta, barren con la flora bacteriana presente. En ese sentido se sabe que el uso de cisaprida acelera el tránsito, reduciendo la densidad de bacterias metanogénicas con un aumento de la excreción de hidrógeno. En cambio, loperamida disminuye el tránsito, aumentando la flora metanogénica (hecho que representa lo que sucede a pacientes constipadas, que tienen flora mayoritariamente productora de metano). Conclusión: La interacción entre motilidad y flora bacteriana es compleja y está poco estudiada fundamentalmente debido a dificultades técnicas.

Microflora is the set of microbacterium colonies covering the digestive tract surface. Each human subject hosts ca. 100 billions of colonies of 400 different species, b23wiodiversity that facilitates life and development of the whole. Bacteria concentration increases throughout the digestive tract, reaching concentrations of 1012 CFU/ml in the colon. Motility of the small intestine is propulsive with a sweeping phase, allowing for the growth of bacteria. On the contrary, motility of the colon is very slow and non-propulsive during fasting and sleeping. Only during wakefulness and postprandial period there are wide-ranging and quickly progressive contraction waves in oral-anal direction. Interaction between bacteria present in lumen and the contraction waves is very hard to assess. This effect has been studied based on drugs that alter motility, and when it increases, they sweep the existing gut flora. In this sense, it is known that the use of cisapride accelerates the transit, reducing the density of methanogenic bacteria with an increase in the hydrogen excretion. On the other hand, loperamide slows down transit, causing an increase of the methanogenic flora (which represents what happens to constipated patients with flora that produces mainly methane). Conclusion: Interaction between motility and gut flora is complex and has not been enough studied mainly due to technical difficulties.

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.

Effect of Bacillus subtilis PB6, a natural probiotic on colon mucosal inflammation and plasma cytokines levels in inflammatory bowel disease.

The pathophysiology of inflammatory bowel disease (IBD) involves the production of diverse lipid mediators, namely eicosanoid, lysophospholipids, and platelet-activating factor, in which phospholipase A2 (PLA2) is the key enzyme. Thus, it has been postulated that control of lipid mediators production by inhibition of PLA2 would be useful for the treatment of IBD. This hypothesis has been tested in the present study by examining the therapeutic effect of a novel natural probitic Bacillus subtilis PB6 (ATCC- PTA 6737). B. subtilis PB6 is found to secrete surfactins (cyclic lipopeptides) which have anti-bacterial potential. These surfactins inhibit PLA2, a rate-limiting enzyme involved in the arachidonic acid associated inflammatory pathway and could downregulate the inflammatory response by regulating the eicosanoid and cytokine pathways. With this concept, an experimental animal trial has been conducted in a rat model of 2, 4, 6-trinitrobenzene sulfonic acid (TNBS)-induced colitis. The oral administration of PB6 suppresses the colitis as measured by mortality rate, changes in the weight gain, colon morphology and the levels of plasma cytokines. The animals treated orally with PB6 at 1.5 x 10(8) CFU/kg thrice daily from day 4 to 10 significantly improve gross pathology of the colon and regain the colon weight to normal (p < 0.05), compared to TNBS-induced positive control. The plasma levels of pro-inflammatory cytokines (TNF-alpha, 1L-1beta, IL-6 and IFN-gamma) are also significantly lowered (p < 0.05) and anti-inflammatory cytokine (IL-I0 and TGF-beta) significantly (p < 0.05) increased after the oral administration of PB6 on day 11. The present study supports the concept that PB6 inhibits PLA2 by the secreting surfactins. In a clinical investigation, it is found to be well tolerated by all the healthy volunteers.

Bacterial translocation in rats nonfunctioning diverted distal colon

PURPOSE: To investigate whether the alterations of the diverted colon segment mucosa, evidenced in fecal colitis, would be able to alter Bacterial Translocation (BT). METHODS: Sixty-two Wistar male rats ranging from 220 to 320 grams of weight, were divided in two groups: A (Colostomy) and B (Control), with 31 animals each one. In group A, all animals underwent end colostomy, one stoma, in ascending colon; and in the 70th POD was injected in five rats, by rectal route diverted segment - 2ml of a 0.9 percent saline solution in animals (A1 subgroup); in eight it was inoculated, by rectal route, 2ml of a solution containing Escherichia coli ATCC 25922 (American Type Culture Collection), in a concentration of 10(8) Colony Forming Unit for milliliters (CFU/ml) - A2 Subgroup; in ten animals the same solution of E. coli was inoculated, in a concentration of 10(11) CFU/ml (A3 Subgroup); and in eight it was collected part of the mucus found in the diverted distal colonic segment for neutral sugars and total proteins dosage (A4 subgroup). The animals from the group B underwent the same procedures of group A, but with differences in the colostomy confection. In rats from subgroups A1, A2, A3, B1, B2, and B3 2ml of blood were aspirated from the heart, and fragments from mesenteric lymphatic nodule, liver, spleen, lung and kidney taken for microbiological analysis, after their death. This analysis consisted of evidencing the presence of E. coli ATCC 25922 CFU. Mann-Whitney and ANOVA Tests were applied as analytic techniques for association of variables. RESULTS: The occurrence of BT was evidenced only in those animals in which inoculated concentration of E. coli ATCC 25922, reached levels of 10(11)CFU/ml, i.e. in Subgroups A3 and B3, although, being significantly greater (80 percent) in those animals without colostomy (subgroup B3) when compared to the ones with colostomy (20 percent) from the subgroup A3 (P <0.05). Lung, liver and mesenteric lymphatic...

OBJETIVO: Investigar se as alterações do cólon desfuncionalizado, evidenciadas na colite de derivação fecal, seriam capazes de permitir Translocação Bacteriana (TB), ou se a mucosa intestinal atrofiada permitiria a passagem de bactérias para órgãos à distância. MÉTODOS: Foram utilizados 62 ratos Wistar, machos, pesando entre 220 e 320 gramas, divididos em dois grupos: A (Colostomia) e B (Controle), contendo cada um 31 animais. No grupo A, os animais foram submetidos à colostomia, terminal boca única, em cólon ascendente. A partir do 70° dia de observação os seguintes procedimentos foram adotados: em cinco ratos foi injetado por via retal no segmento desfuncionalizado - 2ml de uma solução salina 0,9 por cento nos animais (subgrupo A1); em oito inoculou-se, por via retal, uma solução de 2ml contendo Escherichia coli ATCC 25922 (American Type Culture Collection), na concentração de 10(8) Unidades Formadoras de Colônias por mililitros (UFC/ml) - Subgrupo A2; em dez animais inoculava-se a mesma solução de E. coli, na concentração de 10(11)UFC/ml (Subgrupo A3); e em oito colhia-se o muco do segmento colônico distal desfuncionalizado, para dosagens de açúcares neutros e proteínas totais (subgrupo A4). Os animais do grupo B foram submetidos aos mesmos procedimentos do grupo A, e não foram submetidos à colostomia. Nos animais dos subgrupos A1, A2, A3, B1, B2, e B3, após serem mortos, realizou-se punção cardíaca para coleta de 2ml de sangue e retiraram-se fragmentos de tecidos de linfonodo do mesocólon, fígado, baço, pulmão e rim, para análise microbiológica. Essa análise consistia em evidenciar a presença de UFC de Escherichia coli ATCC 25922. Os testes de Mann-Whitney e Anova foram aplicados como técnicas investigativas para associação das variáveis. RESULTADOS: A ocorrência de TB, só foi evidenciada nos animais em que a concentração inoculada de Escherichia coli ATCC 25922, atingia níveis de 10(11)UFC/ml, ou seja, nos Subgrupos A3 e B3, no entanto,...

Digestive tract microbiota in healthy volunteers

PURPOSE: The aim of this study was to standardize the methods of sample collection of mucus from the digestive tract and to determine the microbiota in healthy volunteers from Brazil, collecting samples from the mouth, esophagus, stomach, duodenum, jejunum, ileum, colon, and rectum. METHODS: Microbiota of selected healthy volunteers from the oral cavity (n=10), the esophagus (n=10), the upper digestive tract (n=20), and the lower digestive tract (n=24) were evaluated through distinct collection methods. Collection methods took into account the different sites, using basic scraping and swabbing techniques, stimulated saliva from the oral cavity, irrigation-aspiration with sterile catheters especially designed for the esophagus, a probe especially designed for upper digestive tract, and a special catheter for the lower digestive tract. RESULTS: (i) Mixed microbiota were identified in the oral cavity, predominantly Gram-positive aerobic and anaerobic cocci; (ii) transitional flora mainly in the esophagus; (iii) Veillonella sp, Lactobacillus sp, and Clostridium sp in the stomach and duodenum; (iv) in the jejunum and upper ileum, we observed Bacteroides sp, Proteus sp, and Staphylococcus sp, in addition to Veillonella sp; (v) in the colon, the presence of "nonpathogenic" anaerobic bacteria Veillonella sp (average 10(5) UFC) indicates the existence of a low oxidation-reduction potential environment, which suggests the possibility of adoption of these bacteria as biological markers of total digestive tract health. CONCLUSIONS: The collection methods were efficient in obtaining adequate samples from each segment of the total digestive tract to reveal the normal microbiota. These procedures are safe and easily reproducible for microbiological studies.

OBJETIVO: Padronizar os métodos de coleta do muco do trato digestivo e determinar a microbiota, em voluntários saudáveis no Brasil, coletando amostras da boca, esôfago, estômago, duodeno, jejunos e íleo, cólons e reto. MÉTODOS: A microbiota de voluntários saudáveis foi avaliada através de diferentes métodos de coleta: cavidade oral (n=10 voluntários), do esôfago (n=10), do trato digestivo alto (n=20) e do trato digestivo baixo (n=24). Métodos de coleta foram adotados em cada sítio restrito, usando derramar saliva, técnica de esfregar a mucosa e saliva estimulada da cavidade oral, irrigação-aspiração, cateteres específicos designados para o esôfago, sonda especial para o trato digestivo alto e cateteres especiais para o trato digestivo baixo. RESULTADOS: Identificados: (i) na cavidade oral, microbiota mista, predominando cocos aeróbios e anaeróbios Gram positivos; (ii) no esôfago, flora transitória; (iii) no estômago e duodeno, Veillonella sp, Lactobacillus sp and Clostridium sp; (iv) no jejuno e íleo proximal, Bacteróides sp, Proteus sp and Staphilococcus sp, além da Veillonella sp ; (v) no colon, foi revelada a presença "não patogênica" da bactéria anaeróbica Veillonella sp numa concentração média de 10(5) unidades formadoras de colônia, indicando um meio de baixo potencial de oxido-redução e a possibilidade de se conceituar esta bactéria como um marcador biológico do trato digestivo total em sadios. CONCLUSÃO: Estes métodos de coleta foram considerados eficientes para obtenção adequada de amostra em cada segmento do trato digestivo total para caracterizar a microbiota normal. Estes procedimentos são seguros e facilmente reprodutível para estudo microbiológico.

Cell adherence--a determinant of virulence in Yersinia enterocolitica.

The adherence of pathogenic bacteria to eukaryotic cells plays a central role in their ability to colonize the mucosal epithelial surfaces. The adherence by Y. enterocolitica to the mucosal surface of the gut is the initiating event leading to penetration of mucosa. Adhesion of 10 probable pathogenic and one non-pathogenic isolate was studied using ileum and colon epithelial cells of mouse for 90 minutes. Adhesion study revealed that isolates of Y. enterocolitica had a good adhesive property while non pathogenic showed negligible adherence. All isolates showed better adherence to colon epithelial cells. The organism continued to be excreted in faeces up to 8-10 days after oral feeding. Adhesion positive isolates were found to be virulent when tested in mice for diarrhoea and death. Adhesion was found to be thermoregulated.

Efecto citotóxico en colon humano de Escherichia coli enterohemorrágico aislado de terneros con diarrea sanguinolenta / Cytotoxic effect in human colon of enterohemorrhagic Escherichia coli isolated from calves with bloody diarrhea

Escherichia coli productor de toxina Shiga (STEC) es el patógeno emergente en alimentos de mayor impacto, siendo su principal reservorio el ganado bovino. STEC puede causar diarrea, colitis hemorrágica y síndrome urémico hemolítico. El presente trabajo estudió la acción citotóxica de dos cepas de STEC aisladas de heces de terneros diarreicos en colon humano in vitro. Los fragmentos se montaron como un diafragma en una cámara de Ussing y se incubaron con las cepas patógenas. El flujo neto absortivo de agua (Jw) disminuyó y la corriente de cortocircuito (Isc) aumentó significativamente (P < 0,01) con respecto al control negativo. Los tejidos presentaron erosión de la mucosa, exfoliación del epitelio, y presencia de pseudomembranas en el lumen. A nivel de la lámina propia se observaron lesiones circulatorias leves. Una moderada infiltración de neutrófilos se observó en el lumen y en las células epiteliales. Las criptas colónicas no se vieron afectadas. El grado de lesión fue similar en ambas cepas experimentales. Este es el primer estudio que demuestra que cultivos de cepas de STEC aisladas de ganado bovino producen efectos citotóxicos en colon humano in vitro.

Shiga toxin-producing E. coli (STEC) is one of the most important emergent pathogen in foods, being its main reservoir bovine cattle. STEC can cause diarrhea, hemorrhagic colitis and hemolytic-uremic syndrome. The present work have studied the cytotoxic action in human colon of cultures of two STEC strains isolated from faeces of calves with bloody diarrhea. Colonic mucosa was mounted as a diaphragm in a Ussing chamber and incubated with the cultures of pathogenic strains. Net water flow (Jw) decreased and the short-circuit current (Isc) increased significantly (p < 0,01) compared to negative control. Tissues showed an erosion of the mucose, epithelial exfoliation, and presence of pseudo-membranes in the lumen. Mild circulatory lesions were observed in the lamina propia. A moderate neutrophils infiltration was observed in the lumen and into the epithelial cells. Colonic crypts were not disrupted. Both experimental strains caused a similar lesion on colon tissues. This is the first study that shows that cultures of STEC strains isolated from bovine cattle produce cytotoxic effects in vitro in human colon.

Efeitos da esplenectomia na peritonite causada por lesão traumática do cólon: estudo em ratos / Effects of splenectomy on peritonitis produced by a colonic injury: study in rats

OBJETIVO: Estudar o efeito da esplenectomia na infecção intra-abdominal com bactérias da flora enteral, liberadas para a cavidade abdominal através de uma lesão induzida no cólon de ratos Wistar. MÉTODOS: Foram utilizados 64 animais, sendo 20 do Grupo A1 (normais sem sutura da lesão), 22 do Grupo A2 (normais com sutura da lesão) e 22 do Grupo B (esplenectomizados e com sutura da lesão). Os animais foram submetidos à laparotomia mediana e a indução da peritonite intra-operatória foi obtida através de lesão do cólon previamente distendido pela introdução de uma sonda naso-gástrica via retal e injeção de 2 ml de soro fisiológico. Foram realizados exames bacteriológicos de lavado abdominal obtido por swab esterelizado e exame microscópico de segmento suturado do cólon de amostras obtidas dos grupos A2 e B com 48hs, 96hs e 12 dias de pós-operatório. Todos os animais foram submetidos a necropsia por ocasião do óbito ou no 12º. dia de pós-operatório quando os sobreviventes foram sacrificados. RESULTADOS: Agentes bacterianos semelhantes foram encontrados nos três grupos: E.coli (100 por cento); Enterococcus faecalis (97 por cento); P. mirabilis (90 por cento); Klebsiela pneumoniae (70 por cento); Citobacter freundi (70 por cento) e Enterobacter aglomerans (63 por cento). O exame microscópico revelou menor reação inflamatória no grupo esplenectomizado. A causa da morte na maioria foi peritonite nas primeiras 96hs. Houve alto índice de significância de mortalidade entre os animais do Grupo B (80 por cento) em relação ao Grupo A2 (sem mortalidade) e em relação ao Grupo A1 (35 por cento). CONCLUSAO: Houve alto índice de significância de mortalidade em vigência de peritonite nos animais esplenectomizados em relação aos animais que não foram esplenectomizados.

Symptomatic environmental enteropathy in infancy: bacterial proliferation, funcional and morphological alterations of the small bowel

Asymptomatic Environmental enteropathy may occur in the low social economic stratum of the population temporarily, thus contributing to marginal malnutrition. Bacterial proliferation in the upper portions of the small bowel may be responsible for alterations in the digestive-absorptive function leading to nutritional dwarfism. Forty infants of the Cidade Leonor slum who were under one year of age and presented with asymptomatic environmental enteropathy were investigated for digestive-absorptive function, bacterial proliferation in the small bowel lumen, and jejunal morphology. The mean value of the D-xylose absorption test was 21.0 ñ 10.0 mg per cent, significantly lower than controls (48.0 ñ 13.8 mg per cent) (p < 0.001). Bacterial proliferation in the small bowel of the colonic type was identified in 25 (62,5 per cent) of the infants and jejunal mucosa abnormalities were found in 29(72.5 per cent) of the specimens. Grade II villous atrophy was the most frequent alteration found. The inflammatory infiltration in the lamina propria increased in the total group, varying from light to severe. Alterations in the microecology of the small intestine can occur even in the absence of diarrhea. Therefore, the nonexistence of symptoms does not necessarily imply a condition of weillbeing. If true measures are proposed to improve the quality of life in these poor communities the whole infant population must be taken into account and not only the group with overt symptoms