Outbreak investigation of a campus bacterial dysentery by water source pollution in Lhasa City / 中国学校卫生

Objective@#To investigate risk factors and the nature of the outbreak of bacillary dysentery in Lhasa City, so as to customize targeted prevention and control measures.@*Methods@#Using on site epidemiological investigation, the suspected, probable and confirmed cases of bacillary dysentery in one school and one kindergarten in Lhasa City from June 26 to July 1, 2022 were collected, and additional cases were identified through interview from school staffs and family members, reviewing morning examination records and tracking records of school illness related absence. A case control study was conducted to investigate suspicious meals and drinking raw water, and polymerase chain reaction (PCR) was performed to detect Shigella line nucleic acid fragment in the patients feces, anal swabs, retained food, and terminal water.@*Results@#A total of 55 cases were found in two schools, with the prevalence rate of 15.41% in total and 16.71% in students ( n =53), 7.5% in staff ( n =2). The epidemic curve was suggestive of a point source exposure. The prevalence rate among students who walk to school and students who live in the school showed no difference (16.10%，17.09%)( χ 2=0.05, P >0.05), and the prevalence rate was higher among elementary school students than kindergarten students (19.83%，6.67%)( χ 2=7.13, P <0.05). Case control comparisons showed a direct association between drinking raw water and morbidity in the case and control groups during June 24-26 ( OR=4.01, 95%CI =1.75-9.19, P < 0.05). A total of 23 fecal Shigella nucleic acid positives were detected from the two schools, two from the end water in front of the cafeteria door, and two from sludge in the sewage pipe around the wellhead.@*Conclusions@#The outbreak of bacillary dysentery is caused by the contamination of the pipe network water. Health administrative departments should improve the supervision and management of drinking water health safety, and schools should strengthen the management of water supply facilities for effectively prevent of waterborne infectious disease outbreaks.

Hospitalizaciones por diarrea con sangre en un centro pediátrico de referencia en Uruguay

Introducción: La diarrea con sangre es un motivo frecuente de admisión hospitalaria en niños, con gastroenteritis aguda; en la mayoría de los casos se tratan de infecciones leves y autolimitadas, pero pueden producirse complicaciones graves. Objetivos: Describir la etiología y características clínico- evolutivas de los niños menores de 15 años hospitalizados por diarrea con sangre en el Hospital Pediátrico, Centro Hospitalario Pereira Rossell entre los años 2012- 2023. Materiales y métodos: Estudio retrospectivo mediante revisión de historias y registros de laboratorio. Variables: demográficas, estado nutricional, hidratación, motivos de hospitalización, ingreso unidades de cuidados intensivos (UCI), enteropatógenos, tratamientos, evolución. Resultados: Se incluyeron 229 niños, mediana de edad de 8 meses; sexo masculino 61%; eutróficos 88%, bien hidratados 55%, con comorbilidades 11%, prematurez 6,5%. El motivo de hospitalización fue diarrea con sangre/disentería sin otro síntoma 45%. Se solicitó coprovirológico/coprocultivo en 98% y detección por técnicas de ácidos nucleicos en materia fecal 5,2%. Se identificó al menos un agente patógeno en 34,3%: Shigella sp. 38%; Salmonella sp. 19,5%; coinfecciones en 12%. Se indicaron antibióticos a 86%; ceftriaxona 62%, azitromicina 35%. Ingresaron a UCI 6,5% (15), presentaron complicaciones 10/14, fallo renal agudo 5 y alteraciones del medio interno 3. La mayoría presentó buena evolución. Conclusiones: La diarrea con sangre/disentería continúa siendo una causa importante de hospitalización afectando en su mayoría a niños sanos menores de 5 años. Los patógenos detectados con mayor frecuencia fueron bacterias principalmente Shigella sp., Salmonella sp. y E coli diarreogénicas. Se reportó alta prescripción de antibióticos, cumpliendo en la mayoría de los casos con las recomendaciones.

Introduction: Bloody diarrhea is a common reason for hospital admission in children with acute gastroenteritis; In most cases these are mild and self-limiting infections, but serious complications can occur. Goals: To describe the etiology and clinical-evolutionary characteristics of children under 15 years of age hospitalized for bloody diarrhea at the Pediatric Hospital, Centro Hospitalario Pereira Rossell between the years 2012-2023. Materials and methods: Retrospective study through review of histories and laboratory records. Variables: demographics, nutritional status, hydration, reason for hospitalization, intensive care unit (ICU) admission, enteropathogens, treatments, evolution. Results: 229 children were included, median age 8 months; male sex 61%; eutrophic 88%, well hydrated 55%, with comorbidities 11%, prematurity 6.5%. The reason for hospitalization was bloody diarrhea/dysentery without other symptoms 45%. Coprovirological/coproculture was requested in 98% and detection by nucleic acid techniques in fecal matter was requested in 5,2%. At least one pathogenic agent was identified in 34,3%: Shigella sp. 38%; Salmonella sp 19,5%; coinfections in 12%. Antibiotics were indicated for 86%; ceftriaxone 62%, azithromycin 35%. Were admitted to the ICU 6,5% (15), 10/14 had complications, 5 had acute kidney failure and 3 had alterations in the internal environment. The majority had a good evolution. Conclusions: Bloody diarrhea/dysentery continues to be an important cause of hospitalization, affecting mostly healthy children under 5 years of age. The most frequently detected pathogens were bacteria, mainly Shigella sp., Salmonella sp. and diarrheagenic E coli. High prescription of antibiotics was reported, complying in most cases with the recommendations.

Introdução: A diarreia com sangue é um motivo comum de internação hospitalar em crianças com gastroenterite aguda; Na maioria dos casos, estas são infecções leves e autolimitadas, mas podem ocorrer complicações graves. Metas: Descrever a etiologia e as características clínico-evolutivas de crianças menores de 15 anos internadas por diarreia sanguinolenta no Hospital Pediátrico Centro Hospitalario Pereira Rossell entre os anos de 2012-2023. Materiais e métodos: Estudo retrospectivo por meio de revisão de histórias e registros laboratoriais. Variáveis: dados demográficos, estado nutricional, hidratação, motivo da internação, internação em unidade de terapia intensiva (UTI), enteropatógenos, tratamentos, evolução. Resultados: foram incluídas 229 crianças, mediana de idade 8 meses; sexo masculino 61%; eutrófico 88%, bem hidratado 55%, com comorbidades 11%, prematuridade 6,5%. O motivo da internação foi diarreia sanguinolenta/disenteria sem outros sintomas 45%. O estudo coprovirologico/coprocultivo foi solicitado em 98% e a detecção por técnicas de ácidos nucleicos em matéria fecal foi solicitada em 5,2%. Pelo menos um agente patogênico foi identificado em 34,3%: Shigella sp. 38%; Salmonella sp. 19,5%; coinfecções em 12%. Os antibióticos foram indicados para 86%; ceftriaxona 62%, azitromicina 35%. Foram internados em UTI 6,5% (15), 10/14 apresentaram complicações, 5 tiveram insuficiência renal aguda e 3 apresentaram alterações no meio interno, a maioria teve boa evolução. Conclusões: A diarreia/disenteria com sangue continua a ser uma causa importante de hospitalização, afetando sobretudo crianças saudáveis ​​com menos de 5 anos de idade. Os patógenos mais frequentemente detectados foram bactérias, principalmente Shigella sp., Salmonella sp. e E. coli diarreiogênica. Foi relatada elevada prescrição de antibióticos, cumprindo na maioria dos casos as recomendações.

MICROBIAL PROFILE AND ANTIBIOTIC SUSCEPTIBILITY OF BACTERIAL PATHOGENS ISOLATED FROM PAPER CURRENCIES CIRCULATING IN SOME RESTAURANTS AND BUTCHERIES IN HAWASSA, SIDAMA, ETHIOPIA, 2020-21

Currency notes could play a signicant role in transmitting pathogenic microorganisms amongst individuals in the society. This study was aimed to determine the microbial prole and Antibiotic susceptibility of bacterial pathogens isolated from Ethiopian paper notes in circulation. 64 currency paper notes of different denomination were tested for bacterial contamination using standard microbiological methods. Antibiotic susceptibility proles of the isolates were determined with approved methods. Results were analyzed using descriptive statistics. Overall mean AMBC was 4.08 log units, with the highest 6.58 log units recorded from denomination 5 followed by 4.50, 3.03, 2.20 log units from denominations 10, 50 and 100 respectively. Total Coliforms (TC) displayed the same pattern with the highest mean counts of 6.52 log units, from denomination 5 and lowest counts of 2.19 log units from denomination 100. Out of 64 currency notes, 35 (54.7%) were contaminated with bacteria. The predominant bacteria isolates were E. coli (60.5%), Salmonella spp. (23.6%) and Shigella spp. (13.2%). Each isolate was resistant to four or more antibiotics tested. All isolates were resistant against Cefepime and Tetracycline and sensitive to Ceftriaxone. This study revealed that currency notes are contaminated with pathogenic bacteria and in most cases these bacterial isolates were resistant to commonly prescribed antibiotics. Therefore, contaminated notes are identied as potential public health threat, because pathogens can be spread by circulating the notes and become source of infection. Awareness creation is important among public in this regard.

Susceptibility of Escherichia coli, Salmonella typhi and Shigella spp to Ethanoic Extract of Lawsonia inermis

Background: The acceptance of traditional medicine as an alternative form of healthcare and the development of microbial resistance to the available antibiotics has led researchers to investigate the antimicrobial activity of plant extracts. Aim: This was to evaluate antibacterial activity and potential effect of Lawsonia inermis leaves against three tests organisms namely: Escherichia coli, Salmonella typhi, and Shigella. Methodology: Ethanoic extracts of Lawsonia inermis was obtained. The extracts were boiled, macerated, soaked and the implementation of the extracts to determine the antimicrobial activities on culture was performed by diffusion method. Three antibiotics (Gentamicin, Ciprofloxacin and Cefataxime) were used as control for the test organisms respectively. Results: The inhibition of each test organism was achieved in one or two extracts. Escherichia coli had the highest (7.25mm) zone of inhibition from soaked extract with lowest (5.00mm) zone of inhibition from boiled extract, Salmonella typhi had the highest (11.63mm) zone of inhibition from boiled extract with lowest (8.25mm) zone of inhibition from macerated extract, and Shigella had the highest zone of inhibition 19.50mm from soaked extract, and had the lowest zone of inhibition 12.63mm from boiled extract. Furthermore, the soaked ethanoic extract had a zone of inhibition ranging from 7.25mm- 19.50mm. Also, the ethanoic extract boiled had zones of inhibition ranging from 5.00mm – 12.63mm, and the ethanoic extract macerated had a zone of inhibition range of 6.63mm- 17.75mm. The zones of inhibition produced by the controls are; gentamicin produced zones of inhibition ranging from 25.00mm – 26.00mm, ciprofloxacin produced zones of inhibition ranging from 20.00mm – 22.00mm, and cefataxime produced zones of inhibition ranging from 18.00mm – 21.00mm. The Statistical analysis was applied to the result using the one-way ANOVA test to compare the differences in the means. Conclusion: The results indicated that there was no significant difference in the effects of the ethanoic extracts of Lawsonia inermis on the tests organisms S. typhi, E. coli and Shigella and the controls. (p<0.05, F Cal = 0.103, F Tab = 4.257).

Usefulness of the outer membrane proteins of Shigella sonnei in developing an antibody-based immunoassay for the diagnosis of shigellosis

@#Conventional culture method and biochemical tests remain as the ‘gold standard’ method for the identification of S. sonnei which are time-consuming. We have discovered previously the potential of three OMPs of S. sonnei (33.3 kDa, 43.8 kDa and 100.3 kDa) as biomarkers in the diagnostic test for shigellosis. Here, we evaluated the performance of the outer membrane proteins of S. sonnei for the development of an antibody-based immunoassay for the detection of S. sonnei infections. All threetarget proteins were specifically recognized when probed with S. sonnei sera. In addition, another two potential proteins of molecular weight 29.0 kDa and 88.2 kDa in size were also exclusively recognized by the IgA when probed with S. sonnei sera. The optimized ELISA demonstrated higher sensitivity and specificity which exceeded 86.0%. In conclusion, the identified target proteins showed great potential as diagnostic biomarkers for the detection of S. sonnei infections in patients.

Protective effect and related mechanism of tea saponin on Shigella infection / 中华检验医学杂志

Objective:To explore the protective effects and related mechanism of tea saponin (TS) on intestinal inflammation due to Shigella infection. Methods:In vitro, the antibacterial activity of TS was detected by standard broth microdilution method. The absorbance at 600 nm of the bacterial liquid was detected by Microplate Reader under different concentrations of TS, and the growth curve was drawn. Bacterial count was obtained by plate colony counting. In vivo, 15 mice were divided into 3 groups ( n=5 each): control group, Sf301 group and TS group. Sterile water or TS was applied to mice in the Sf301 group and the TS group per gavage once a day for 8 days, and the mouse model of Shigella infection was established on day 3. The disease activity index (DAI) was used to evaluate the general condition of mice. The mice were sacrificed on day 8. Colon length was measured and colon tissues were stained with HE to analyze the pathological changes. The cecal contents and feces of mice were taken for plate counting and Shigella load was obtained. Real-time fluorescent quantitative PCR (RT-qPCR) was used to detect the mRNA expression levels of inflammatory factors. Results:(1) In vitro, the MIC of TS was 1 024 μg/ml. The plate counting and A600 of TS decreased in proportion to increasing concentrations (256, 512, 1 024 μg/ml) in comparison with the control group (all P<0.05). (2) In vivo, colon length was (7.70±0.24) cm in the control group and (7.35±0.41) cm in the TS group, which was significantly longer than that of the Sf301 group ([6.13±0.05] cm, P<0.05). Histopathological examination evidenced colonic epithelial cells shedding, decreased goblet cells, and inflammatory cell infiltration in the colon tissue of the Sf301 group. In the TS group, the colonic mucosa was intact without significant inflammatory cell infiltration. Bacterial load in cecal contents was significantly lower in the TS group than in the Sf301 group ( P<0.05). The level of tumor necrosis factor-α was significantly lower, and the level of interleukin-10 was significantly higher in the TS group than in the Sf301 group (all P<0.05). Conclusion:TS can effectively inhibit Shigella and alleviate Shigella infective enteritis by reducing Shigella load and inhibiting inflammation.

Antimicrobial resistance patterns and prevalence of integrons in Shigella species isolated from children with diarrhea in southwest Iran

Objective: To investigate the antimicrobial resistance patterns and prevalence of integrons in Shigella species isolated from children with diarrhea in southwest Iran. Methods: In this study, 1 530 stool samples were collected from children under 15 years with diarrhea referred to teaching hospitals in Ahvaz and Abadan, southwest Iran. Shigella spp. were identified by standard biochemical tests and PCR. The antibiotic resistance pattern of all Shigella isolates was determined by the disk diffusion method and minimum inhibitory concentration (MIC) by E-test. Results: Of 1 530 stool samples, 91 (5.9%, 91/1 530) were positive for Shigella spp. the most common Shigella isolates were Shigella flexneri 47 (51.6%, 47/1 530). Antibiotic susceptibility tests showed that the highest antibiotic resistance was related to trimethoprim-sulfamethoxazole (87.9%, 80/91) and ampicillin (86.8%, 79/91). Multiplex PCR results revealed that 56% and 86.9% of Shigella isolates carried integron class I and integron class II genes, respectively. None of the isolates included the integron class III gene. Conclusions: The high prevalence of multi-drug resistance in Shigella isolates in our area increases the concerns about dissemination of the antibiotic-resistant isolates in this bacterium.

Miocarditis por gram negativos / Gram-Negative Myocarditis

Resumen Objetivo: describir las características epidemiológicas, clínicas y microbiológicas de los pacientes que cursan con miocarditis por Enterobacterias. Métodos: se realizó una revisión sistemática de la literatura, en la que se incluyeron Pubmed, Ovid, Scopus, SciELO y LILACS sin exclusión por tipo de idioma. La población objetivo de estudio fueron los pacientes con diagnóstico de infección bacteriana por bacilo gram negativo mediante cultivo, técnicas moleculares o histopatología, y quienes presentaban biopsia de miocardio o, en su defecto, resonancia magnética cardiaca con hallazgos sugestivos de miocarditis. Resultados: se encontraron 742 artículos, de los cuales se incluyeron 24; en estos se reportaron 27 pacientes. La edad promedio fue de 31 años. El 81% de los pacientes eran de sexo masculino. El síntoma principal fue diarrea (80%), seguido de fiebre (53%) y dolor torácico (38%). El 37% de los pacientes fallecieron. El hallazgo más común en el electrocardiograma fue la elevación del segmento ST (36,7%). En quienes se realizó ecocardiograma se encontraron anormalidades en 50% de los casos, siendo más frecuente la disminución en la fracción de eyección. El microorganismo más común fue el Campylobacter jejuni, seguido por Salmonela sp. Conclusiones: la miocarditis causada por enterobacterias es más frecuente en pacientes adultos jóvenes de sexo masculino. Los síntomas gastrointestinales suelen estar presentes al momento de la presentación clínica. El diagnóstico requiere de alta sospecha clínica teniendo en cuenta que las anormalidades eléctricas y en ecocardiograma no se encuentran en todos los pacientes.

Abstract Objective: To describe the epidemiological, clinical, and microbiological characteristics of patients with myocarditis due to Enterobacteria. Methods: A systematic review was carried out on the literature, which included Pubmed, Ovid, Scopus, SciELO, and LILACS, with no exclusions due to language. The target population of the study were patients with a diagnosis of bacterial infection due to gram negative bacillus by means of a culture, or using molecular or histopathology technique. They also had to have had a myocardial biopsy or, if not, a cardiac magnetic resonance scan with findings suggestive of myocarditis. Results: Out of a total of 742 articles found, 24 of these, in which 27 patients were described, were included. The mean age was 31 years, and 81% were male. The main symptom was diarrhoea (80%), followed by fever (53%), and chest pain (38%). More than one-third (37%) of the patients died. The most common finding on the electrocardiogram (ECG) was elevation of the ST segment (36.7%). Abnormalities were found in 50% of the cases, on whom a cardiac ultrasound was performed, with a decrease in the ejection fraction being the most common. The most common microorganism was Campylobacter jejuni, followed by Salmonella spp. Conclusions: Myocarditis caused by enterobacteria is most common in young male patients. The gastrointestinal symptoms are usually present from the clinical onset. The diagnosis requires a high clinical suspicion, taking into account that the abnormalities in the ECG and cardiac ultrasound are not found in all patients.

Acute diarrhea with blood: diagnosis and drug treatment / Diarreia aguda com sangue: diagnóstico e tratamento medicamentoso

Abstract Objective To restate the epidemiological importance of Shigella in acute diarrhea with blood, providing an overview of the treatment and stressing the need for the correct indication of antibiotic therapy. Sources of Data A search was carried out in the Medline and Scopus databases, in addition to the World Health Organization scientific documents and guidelines, identifying review articles and original articles considered relevant to substantiate the narrative review. Synthesis of Data Different pathogens have been associated with acute diarrhea with blood; Shigella was the most frequently identified. The manifestations of shigellosis in healthy individuals are usually of moderate intensity and disappear within a few days. There may be progression to overt dysentery with blood and mucus, lower abdominal pain, and tenesmus. Conventional bacterial stool culture is the gold standard for the etiological diagnosis; however, new molecular tests have been developed to allow the physician to initiate targeted antibacterial treatment, addressing a major current concern caused by the increasing resistance of Shigella. Prevention strategies include breastfeeding, hygiene measures, health education, water treatment, and the potential use of vaccines. Conclusions Acute diarrhea is an important cause of mortality in children under 5 years and shigellosis is the leading cause of acute diarrhea with blood worldwide. The current concern is the increase in microbial resistance to the recommended antibiotics, which brings an additional difficulty to therapeutic management. Although no vaccine is yet available against Shigella, several candidates are undergoing clinical trials, and this may be the most cost-effective preventative measure in future.

Resumo Objetivo Reiterar a importância epidemiológica da Shigella na diarreia aguda com sangue, fornecer uma visão geral do tratamento e ressaltar a necessidade da correta indicação da antibioticoterapia. Fontes dos dados Realizada pesquisa nos bancos de dados Medline e Scopus, além de documentos científicos e diretrizes da Organização Mundial da Saúde, com a identificação de artigos de revisão e artigos originais considerados relevantes para fundamentar a revisão do tipo narrativa. Síntese dos dados Diferentes patógenos têm sido associados à diarreia aguda com sangue, a Shigella é o mais frequente. As manifestações da shigelose em indivíduos saudáveis são geralmente de intensidade moderada e desaparecem em poucos dias. Pode haver progressão para disenteria franca com sangue e muco, dor em abdome inferior e tenesmo. A coprocultura bacteriana convencional é o padrão-ouro para o diagnóstico etiológico, porém novos testes moleculares foram desenvolvidos, os quais permitem ao médico iniciar tratamento antibacteriano direcionado, sanar uma grande preocupação atual, devido à crescente resistência da Shigella. Estratégias de prevenção incluem aleitamento, medidas de higiene, educação em saúde, tratamento da água e o potencial uso de vacinas. Conclusões A diarreia aguda é uma importante causa de mortalidade em crianças com menos de cinco anos e a shigelose é a principal causa de diarreia aguda com sangue em todo o mundo. A preocupação atual é o aumento da resistência microbiana aos antibióticos preconizados, o que traz uma dificuldade adicional ao manejo terapêutico. Embora ainda não exista vacina disponível para Shigella, várias candidatas estão em fase de testes clínicos, podem futuramente ser a medida preventiva mais custo-efetiva.

Reverse vaccinology approach for the identification and characterization of outer membrane proteins of Shigella flexneri as potential cellular- and antibody-dependent vaccine candidates

A case study of symptomatic urinary tract infection by Shigella sonnei in adult female and a short review on drug-resistant Shigella species

Shigella species belong to family Enterobacteriaceae and are causative agents of bacillary dysentery. The whole spectrum of disease caused by Shigella species is called Shigellosis. Shigella has four major subgroups: Shigella dysenteriae, Shigella flexneri, Shigella boydii, and Shigella sonnei. S. sonnei causes the mildest form of bacillary dysentery, and in many cases, it causes only mild diarrhea. It is the most common Shigellosis in developed countries. There are few reported cases of asymptomatic bacteriuria due to S. sonnei both in adults and pediatric patients. Few cases of symptomatic urinary tract infection (UTI) are also reported. In pediatric patients, the common risk factor for UTI is found to be vesicoureteric reflux, especially in females. Recent studies done in various countries show an alarming increase in resistance of Shigella species to commonly used antibiotics such as chloramphenicol, ampicillin, co-trimoxazole, nalidixic acid, fluoroquinolones, macrolides, and cephalosporins. Many outbreaks of Shigellosis by multidrug-resistant (MDR) strains have also been reported. Shigella rarely causes extraintestinal manifestations such as hemolytic uremic syndrome, hyponatremia, reactive arthritis, altered neurologic state, bacteremia, UTI, and vulvovaginitis. UTI is a rare complication of Shigella infection. Here, we report a case of UTI due to S. sonnei in an adult female with diabetes mellitus (DM). We have also done a short review of increasing antibiotic resistance among Shigella species. The Institutional Ethics Committee approval was obtained to publish this case study. A 64-year female presented to an outpatient clinic with symptoms of UTI. Urine culture was done by the semi-quantitative method in blood agar plate and MacConkey agar. A Gram-negative bacilli were isolated with a significant colony count of >100,000 cfu/ml. Antibiotic sensitivity was done by both disc diffusion method and minimum inhibitory concentration. Stool culture was also done after 4 days. In this case study, S. sonnei was isolated from urine, but stool culture done after 4 days of treatment with antibiotic was negative. The patient was newly diagnosed with type 2 DM. Hence, DM could be a risk factor for S. sonnei UTI in the elderly. Taking into consideration the emergence of antibiotic resistance among S. sonnei isolates, knowledge of antibiotic sensitivity pattern is crucial in the treatment of such infections. In our study, the isolate was not MDR. It was sensitive to ampicillin, cefixime, cefotaxime, ciprofloxacin, nitrofurantoin, and norfloxacin and azithromycin and resistant to co-trimoxazole and nalidixic acid.

Preliminary Phytochemical Analysis and In vitro Antimicrobial Study of the Root and Stem Bark Extracts of Ficus sycomorus Linn

This study was conducted to carryout preliminary phytochemical analysis and in vitro antimicrobial activities of aqueous and ethanolic root and stem bark extracts of Ficus sycomorus. Qualitative phytochemical analysis for tannins, saponin, terpenoids, flavonoids, alkaloids, glycosides, steroids, phenols, and reducing sugar was done using standard methods. The antimicrobial activities of the extracts were tested against four micro- organisms; Escherichia coli, Staphylococcus aureus, Shigella dysentrae, and Salmonella typhi. Agar well diffusion method was used for the antimicrobial studies. Phytochemical screening of both root and stem bark aqueous extracts showed the presence of tannin, saponin, terpenoid, flavonoid, alkaloids, glycoside, steroid, reducing sugar, and phenol. Glycoside was not detected in both the aqueous and ethanolic extracts of the root bark. The result of the antimicrobial studies showed that the aqueous root extract have higher antimicrobial activity ranging from (2-12 mm) on the tested microorganisms than aqueous stem bark extract (3-9 mm), while for ethanol extract both stem and root bark extract has almost the same effect or antimicrobial activity on the tested pathogens ranging from (2-15 mm) which is having higher activity compared to the aqueous extracts. The Minimum inhibitory concentration (MIC) and Minimum bactericidal concentration (MBC) of both the extracts were found to be 50 mg/mL and 100 mg/mL respectively. From this study, it can, therefore, be concluded that the root and stem bark extract is a potential antimicrobial agent which support the claim of the traditional users of this plant in herbal medicine for the treatment of diseases that are of microbial origin.

Isolation, biochemical characterization, and phylogeny of a cellulose-degrading ruminal bacterium / Aislamiento, caracterización bioquímica y filogenia de una bacteria ruminal degradadora de celulosa / Isolamento, caracterização bioquímica e filogenia de uma bacteria ruminal degradante de celulose

Abstract Background: The isolation of cellulolytic bacteria, which hydrolyze cellulose to cellobiose and glucose, can provide useful information about rumen diversity. Objective: To identify and characterize a microorganism capable of hydrolyzing cellulose, isolated from a cow rumen. Methods: Anaerobic culture techniques were used for isolating cellulose-degrading rumen bacteria. Congo red staining was used to evaluate β-D-glucanase activity, and carbohydrate fermentation pattern was obtained with the kit API 50CHB/E. DNA extraction was performed and the 16S rDNA gene was amplified using 8F (5'-AGA GTT TGA TCC TGG CTC AG-3'), and 1492R (5' GGT TAC CTT GTT ACG ACT T 3') primers. The phylogenetic tree was reconstructed with the algorithm of maximum parsimony (bootstrap 5000), and 16S rDNA sequence was deposited in the NCBI database (accession number: KM094184). Results: The isolated bacterium showed cellulolytic activity detected with Congo red; besides, glycerol, ribose, xylose, sucrose, galactose and glucose were fermented by this bacterium. However, biochemical tests did not identify the bacteria because no match was found at database of API WEB Software. The phylogenetic inference indicated that this bacterium belongs to Shigella genus, with 98% maximal identity respect to the other taxonomic species. Conclusions: Phylogenetic analysis of 16S rRNA genes showed that the rumen isolated bacterium was a member of the genus Shigella, which, under mesophilic conditions, is an interesting candidate for obtaining oligosaccharides from lignocellulosic biomass.

Resumen Antecedentes: El aislamiento de las bacterias celulolíticas, que hidrolizan la celulosa a celobiosa y glucosa, proporciona valiosa información sobre la diversidad del rumen. Objetivo: Identificar y caracterizar un microorganismo capaz de hidrolizar celulosa, aislado de un rumen vacuno. Métodos: Se utilizaron técnicas de cultivo anaeróbico para aislar bacterias ruminales que degradan celulosa. La tinción con rojo Congo se usó para evaluar la actividad β-D-glucanasa y el patrón de fermentación de carbohidratos se obtuvo con el kit API 50CHB/E. Se realizó la extracción de DNA y se amplificó el gen de 16S rDNA utilizando los cebadores 8F (5'-AGA GTT TGA TCC TGG CTC AG-3'), y 1492R (5' GGT TAC CTT GTT ACG ACT T 3'). El árbol filogenético se reconstruyó con el algoritmo de máxima parsimonia (replicas 5000) y la secuencia 16S rDNA se depositó en la base de datos del NCBI (número de acceso: KM094184). Resultados: La bacteria aislada mostró actividad celulolítica detectada con la tinción de rojo Congo; además, esta bacteria fermenta glicerol, ribosa, xilosa, sacarosa, galactosa y glucosa. Sin embargo, las pruebas bioquímicas no permitieron identificar a la bacteria aislada, por no encontrar coincidencias en la base de datos del software API WEB. La inferencia filogenética indicó que esta bacteria pertenece al género Shigella, con 98% de identidad máxima respecto a las otras especies taxonómicas. Conclusiones: El análisis filogenético del gen 16S rRNA mostró que la bacteria aislada del rumen es un miembro del género Shigella que, en condiciones mesófilas, es un candidato interesante para obtener oligosacáridos a partir de biomasa lignocelulósica.

Resumo Antecedentes: As bactérias celulolíticas hidrolizam a celulosa em celobiose e glicose, e o isolamento desses microrganismos fornece informações sobre a diversidade do rúmen. Objetivo: Identificar e caracterizar um microorganismo isolada do rúmen de uma vaca, com capacidade para hidrolisar a celulose. Métodos: Técnicas de cultura anaeróbica foram utilizadas para isolar bactérias ruminais que degradam a celulose. A atividade β-D-glucanase foi mostrada utilizando mancha de vermelho Congo, e o padrão de fermentação de carbohidratos foi obtida com o kit API 50CHB/E. A extracção foi realizada de DNA e amplificou-se os genes 16S rDNA utilizando os iniciadores 8F (AGA GTT TGA 5'-TCC TGG CTC AG-3'), e 1492R (5' CTT GGT TAC GTT ACG TCA T 3'). A árvore filogenética foi reconstruída com o algoritmo de máxima parcimônia (réplicas 5000). A sequência de rDNA 16S foi depositada no banco de dados do NCBI (número de acesso: KM094184). Resultados: O isolado mostrou uma atividade celulolítica com coloração vermelho Congo; además esta bactéria fermentação de glicerol, ribose, xilose, sacarose, galactose e glicose. No entanto, com as provas bioquímicas não se identificou a bactérias isolada, já que não se encontrou na base de dados do software API WEB. A inferência filogenética indicou que esta bactéria pertence ao género Shigella, com 98% de identidade de máximo respeito para outras espécies taxonômicas. Conclusão: A análise filogenética do gene 16S rRNA mostrou as bactérias isoladas do ambiente ruminal como um membro do género Shigella, que condições mesofilicas é um candidato atraente para obter oligossacarídeos da biomassa lignocelulósica.

Clinico etiological spectrum and antibiotic sensitivity profile of bacillary dysentery in a tertiary care hospital in Kashmir, India

Background: Diarrheal disorders along with dysentery constitute the second killer infections in childhood. In fact, more than half of the dysentery cases are recorded in children under 9 years of age. Shigella infection comprises well over 60% of dysentery cases in age group of 6 month to 5 years. Shigella flexneri is the commonest etiology encountered in developing nations. E. coli and campylobacter comprises the second important bacterial isolates in childhood dysentery. The objective of this study was to ascertain the clinical spectrum, etiological profile and local antibiotic sensitivity of the enteropathogens isolated.Methods: 147 serial dysentery cases admitted in GB Panth hospital Srinagar, which is an associated hospital of government medical college Srinagar from October 2014 to September 2015 were taken up for the study. A thorough and detailed history and examination was taken and recorded as per the proforma. Freshly collected stool sample was subjected to gross and microscopic examination; and after due bacteriological instructions was cultured on enrichment and selective media as per the need. Antibiotic sensitivity was done using disc diffusion method.Results: Maximum cases occurred in 1-5 years age group. Malnutrition grades II and III recorded the highest admissions. Most of cases had moderate dehydration. Although not frequent severe anemia, paralytic ileus and renal failure were the commoner complications. Shigella was grown in 12.24% of cases. Among them Shigella flexeneri serotype was encountered in 65% patients. Drug resistance was seen for many of the antibacterials like amoxycillin, ampicillin, norfloxacin, cotrimoxazole and nalidixic acid. However, they were susceptible to ceftriaxone and amikacin in well over 80% cases. E. coli isolates had similar antibiotic sensitivity profiles, with most susceptibility to amikacin and ceftriaxone.Conclusions: Drug sensitivity and resistance pattern is a variable phenomenon and changes from place to place and time to time. Hence there is a need to document the local pattern of an area so as to guide a judicious antibiotic administration.

A novel ready-to-use dry-reagent polymerase chain reaction for detection of Escherichia coli & Shigella species

Background & objectives: Polymerase chain reaction (PCR) has wide acceptance for rapid identification of pathogens and also for diagnosis of infectious conditions. However, because of economic and expertise constraints, a majority of small or peripheral laboratories do not use PCR. The objective of the present study was to develop a dry-reagent PCR assay as an alternative to conventional PCR to assess its applicability in routine laboratory practice using malB gene for identification of Escherichia coli as a model. Methods: A total of 184 isolates were selected for the study comprising clinical isolates of E. coli and non-E. coli including Shigella sp. and a few other control strains. The DNA was isolated from all the isolates. The isolated DNA as well as the overnight grown bacterial cultures were subjected to both conventional wet PCR and dry-reagent PCR. Results: The genomic DNA isolated from E. coli showed amplification of malB gene in both conventional wet and dry-reagent PCR and the band was observed at 491 bp. In dry-reagent PCR, the overnight grown E. coli cells also showed positive result. The non-E. coli strains other than Shigella sp. showed negative in both conventional wet and dry-reagent PCR. Shigella sp. showed positive in both conventional wet and dry-reagent PCR. Interpretation & conclusions: Considering the elimination of genomic DNA isolation step, and similar results with the conventional wet PCR, dry-reagent PCR may be a good alternative for the conventional wet PCR.

Dysentery by CTX-M Type ESBL Producing Shigella flexneri / Disentería por Shigella flexneri productora de BLEE tipo CTX-M

According to the World Health Organization, diarrheal infections cause 525 000 deaths of children under five years of age every year, and shigellosis. Shigellosis is a relevant cause of dysentery, which increases the morbidity and mortality in pediatric patients. Therefore, emergingthe emergence of antimicrobial resistant strains of Shigella is a concerningworrisome problem worldwide. We report the case of a 7-year-old patient with acute dysentery caused by CTX-M Type ESBL Producing Shigella flexneri, being. This was the first case treated in the Specialties Hospital of Specialties of the Armed Forces N°1, in Quito, Ecuador. The antibiogram demonstrated sensibilityshowed sensitivity to ampicillin-sulbactam. As a result, after five days of microbiologically directed treatment, the patient improved his condition without relapse. Proper clinical diagnoses and accurate laboratory studies like stool culture and antibiogram are crucial to givingindicate an appropriate therapy in infections caused by Shigella and other enteric bacilli(AU)

Según la Organización Mundial de la Salud, las infecciones diarreicas provocan 525 000 muertes de niños menores de cinco años de edad cada año. La shigelosis es una causa importante de disentería que aumenta la morbilidad y mortalidad de los pacientes pediátricos. Es por eso que el surgimiento de cepas de Shigella resistentes a los antibióticos es un preocupante problema a nivel mundial. Presentamos el caso de un paciente de 7 años de edad con disentería aguda provocada por Shigella flexneri productora de BLEE tipo CTX-M. Se trata del primer caso tratado en el Hospital de Especialidades de las Fuerzas Armadas Nº 1, en Quito, Ecuador. El antibiograma mostró sensibilidad a la combinación ampicilina/sulbactam. Al cabo de cinco días de tratamiento microbiológico, el paciente mejoró su estado y no se produjeron recaídas. Un diagnóstico clínico correcto, así como estudios precisos de laboratorio como los cultivos de heces y los antibiogramas, son vitales para indicar una terapia apropiada en las infecciones causadas por Shigella y otros bacilos entéricos(AU)

Immunological detection assays for recombinant Shiga toxin & Shigella dysenteriae

Background & objectives: Shiga toxin (Stx) is produced by Shigella dysenteriae, a Gram-negative, facultative anaerobic bacillus that causes shigellosis, haemolytic uraemic syndrome (HUS) and Reiter's syndrome. The detection methods for shiga toxin needs to be rapid, accurate, reliable and must be extensively evaluated under field conditions. The aim of this study was to develop rapid, sensitive and specific detection method for Stx. Methods: Mice and rabbits were immunized with purified recombinant Shiga toxin B (rStxB). Using these antibodies dot ELISA, sandwich ELISA and flow through assay were developed. Results: The high-titre antibodies specifically reacted with purified rStxB. Dot-ELISA, sandwich ELISA and flow-through assay were developed and standardized that could detect StxB with limit of detection (LOD) of 9.75, 9.7 ng/ml and 0.46 ?g/cassette, respectively. Interpretation & conclusions: The rStxB was used to produce antibodies to avoid handling of pathogen. The Flow through assay 'developed was specific, rapid and field amenable.

Antimicrobial resistance, virulence & plasmid profiles among clinical isolates of Shigella serogroups

Background & objectives: Bacillary dysentery caused by Shigella spp. remains an important cause of the crisis in low-income countries. It has been observed that Shigella species have become increasingly resistant to most widely used antimicrobials. In this study, the antimicrobial resistance, virulence and plasmid profile of clinical isolates of Shigella species were determined. Methods: Sixty clinical Shigella isolates were subjected to whole-genome sequencing using Ion Torrent platform and the genome sequences were analyzed for the presence of acquired resistance genes, virulence genes and plasmids using web-based software tools. Results: Genome analysis revealed more resistance genes in Shigella flexneri than in other serogroups. Among ?-lactamases, blaOXA-1was predominantly seen followed by the blaTEM-1B and blaEC genes. For quinolone resistance, the qnr S gene was widely seen. Novel mutations in gyr B, par C and par E genes were observed. Cephalosporins resistance gene, blaCTX-M-15 was identified and plasmid-mediated AmpC ?-lactamases genes were found among the isolates. Further, a co-trimoxazole resistance gene was identified in most of the isolates studied. Virulence genes such as ipaD, ipaH, virF, senB, iha, capU, lpfA, sigA, pic, sepA, celb and gad were identified. Plasmid analysis revealed that the IncFII was the most commonly seen plasmid type in the isolates. Interpretation & conclusions: The presence of quinolone and cephalosporin resistance genes in Shigella serogroups has serious implications for the further spread of this resistance to other enteric pathogens or commensal organisms. This suggests the need for continuous surveillance to understand the epidemiology of the resistance.

In Vitro Susceptibility Of Isolated Shigella Flexneri And Shigella Dysenteriae To The Ethanolic Extracts Of Trachyspermum Ammi And Peganum Harmala

Objective: This study represents the first attempt to investigate the antimicrobial activity of Peganum harmala, and Trachyspermum ammi seeds extract against the isolated bacillary dysentery-causing microorganisms. Methods: T. ammi and P. harmala were extracted by 96% ethanol using Soxhlet apparatus. The extracts were screened for their phytochemical constituents. Their antimicrobial activity against the isolated dysentery-causing microorganisms was evaluated using the agar diffusion method. Results: The antimicrobial activity result showed that, the two isolated bacteria, Shigella flexneri, and Shigella dysenteriae were found to be sensitive to the extract of T. ammi seed with inhibition zones up to 25 mm, compared to the inhibition zone of 20 mm produced by Gentamycin standard drug, this is mainly due to the presence of the different phytochemical in the extract such as tannin, flavonoids, terpenoids which are well known for their antimicrobial effects. The two isolated bacteria were found to be insensitive (zero mm) to P. harmala extract, Amoxicillin, and Amoclan (Amoxicillin+clavulanic acid) standard drugs, this is due to the fact that, the phytochemicals constituents of P. harmala possess the antagonistic effect to each other’s. Addition to; these bacteria became resistant to both Amoxicillin and Amoclan. Conclusion: From the results it concludes, T. ammi seeds extract had a considerable level of antimicrobial activity against bacillary dysentery-causing microorganisms resistant to Amoxicillin and Amoxicillin+clavulanic acid drugs.

Relationship of clustered regularly interspaced short palindromic repeats with virulence genes and resistance genes in Shigella / 西安交通大学学报(医学版)

Objective: To investigate the relationship of the clustered regularly interspaced short palindromic repeats (CRISPR) with resistance genes and virulence genes. Methods: The Shigella genome sequences, resistance genes and virulence genes sequences were obtained from GenBank Database. Then we obtained the distribution of CRISPR1, CRISPR2 and CRISPR-Q1 and the information of repeat and spacers in Shigella by multiple sequences alignment. Meanwhile, the distribution of resistance genes and virulence genes in Shigella were obtained by BLAST and the relationship of the CRISPR with resistance genes and virulence genes was computed by SPSS 17.0. Results: The spacers of CRISPR1 and CRISPR2 showed obvious differences in different Shigella strains, and the CRISPR-Q1 was more widely distributed (over 99%). The virulence genes were widely distributed in Shigella (more than 56%); the distribution of resistance genes (blaOXA-1, camr, Sul2, and tetB) was also wide (over 50%). There were significant differences between the CRISPR1/CRISPR2 and 9 kinds of virulence genes and 4 kinds of resistance genes (P<0.05). There were significant differences between the CRISPR-Q1 and 3 kinds of virulence genes and 4 kinds of resistance genes (P<0.05). There were significant differences between the CRISPR1/CRISPR2, CRISPR-Q1 and the number of virulence genes and resistance genes (P<0.05). There were significant differences between the CRISPR1/CRISPR2 and the number of spacers of CRISPR-Q1 (χ2=61.6, P<0.001). Conclusion: The distribution of CRISPR was quite different in Shigella, and the number of spacers was also different. There were negative correlation of CRISPR of Shigella with some resistance genes and virulence genes. The CRISPR1/CRISPR2 had a positive relationship with the number of the spacers.