Resistance In Enteric Pathogens Research Articles

Distribution of antimicrobial resistance and virulence markers in chicken originated Proteusmirabilis isolates.

Proteus mirabilis is a common enteric bacterium in livestock and humans. The increase and spread of the antimicrobial resistant P. mirabilis is considered alarming worldwide. Transmission mainly occurs through consumption of contaminated poultry products. We investigated antimicrobial resistance (AMR) and virulence markers in broiler chicken-originated P. mirabilis isolates from 380 fecal samples. Phenotypic AMR test was performed against seventeen different antimicrobials. Genotypic AMR test was performed to detect sixteen different AMR genes. The samples were also tested for the presence of eight different virulence genes and biofilm formation. P. mirabilis was isolated in 11% of the samples, with significantly high multidrug-resistant (MDR) prevalence (63%). All isolates were resistant to tetracycline (100%). The combined disc method indicated that all isolates were of extended-spectrum beta-lactamase (ESBL) producers, which was compatible with the high blaTEM prevalence (95%). This was associated with blaTEM being responsible for more than 80% of ampicillin resistance in enteric pathogens. The absence of phenotypically carbapenem-resistant isolates was compatible with the very low prevalences of blaOXA (2%) and blaNDM (0%). All isolates were positive for pmfA, atfA, hpmA, and zapA (100%) virulence genes, while biofilm formation rate (85%) indicated high adherence abilities of the isolates.

New Approaches to Tackling Intractable Issues in Infectious Disease.

Despite major progress in the last several decades in reducing the public and animal health burden of infectious disease a number of issues remain to be resolved and which have thus far been regarded as intractable. These include (i) the persistent carrier state in individuals convalescent from typhoid and typhoid-like infections, (ii) the increasing prevalence of multi-antibiotic resistance in enteric pathogens, much of which is mediated by self-transmissible plasmids, and (iii) parasite infections which are difficult to control by vaccination and where resistance to chemotherapeutics is also increasing. The author describes very recent work carried out by his group to look at resolving these problems in new and imaginative ways.

Fate of enteric bacteria and viruses in silt loam soil amended with biofertilizers made from human feces and urine for crop production

Human excreta can be used as biofertilizers due to their nutrient and organic matter content. Nevertheless, the behavior of microorganisms should be investigated, as enteric pathogens can accumulate in the soil. Therefore, we evaluated the survival and transport of two enteric bacteria (E. coli and Salmonella enterica) and two enteric virus surrogates (MS2 and ΦX-174 bacteriophages) when applied as contaminants of four biofertilizers on Lactuca sativa production. The study was carried out in lysimeters outdoors with repacked silt loam soil, using a randomized block design (RBD) with six treatments and three replicates. Biofertilizers were urea-treated feces, feces composted with organic waste, stored liquid urine, and struvite and were inoculated at 106–107 cfu/pfu g−1 of E. coli and bacteriophages strains and 107–109 of S. enterica. Soil amended with composted feces exhibited the lowest decimal reductions (T90) for the microorganisms evaluated, with 10.2 days for E. coli, 11.9 days for S. enterica, 22.2 days for MS2, and 3.7 days for ΦX-174. Urea-treated feces temporarily hindered the growth and survival of E. coli and S. enterica in the soil. However, both bacteria were present after one month, while MS2 showed a stable concentration with this biofertilizer. E. coli presented a stable behavior when applied with urine, whereas MS2 was stable with urea-treated feces, urine, and struvite. ΦX-174 and S. enterica were not considered good representatives of most resistant enteric pathogens’ behavior in the soil during food production since they were not detected in leachate and showed a rapid die-off in soil. E. coli leached faster and in higher concentrations than MS2, which presented higher concentrations in deeper soil layers, from 10 to 20 cm. Therefore, using urine, struvite, and urea-treated faces implied a higher chance of infection, as a decimal reduction time was not observed during the 36 days of the experiment. As a result, in short-term cultures, it is recommended that additional hygiene barriers are taken to avoid infection since E. coli and MS2 were still detected at the end of the experiment. An interval of 90 days between fertilizing and harvesting is recommended to prevent pathogen infection. These results are the basis for a quantitative risk assessment of human excreta-based biofertilizers for food production.

Pharmacotherapy of resistant enteric pathogens in combination with medicinal plants extracts and antibiotics

Development of resistance to the antimicrobial products has created an evolving problem that has led the clinicians to evaluate a suitable empirical therapy for bacterial diseases and also provoked the technicians and researchers at the laboratory level to rethink about the basic sample testing policies. High rate of resistant organisms develop due to their exposure to such bacteriostatic and bactericidal agents. Such strategies should be developed that have guidelines for sensible use of these antimicrobial products. On the other hand, CDC evaluated certain approvals for clinicians that could help them in the use of these products cleverly that may retard the progress, growth and spread of these resistant pathogens. These medicinal plants have biologically active compounds which have antibacterial activity against the selected multidrug resistant enteric agents which is verified and declared by different traditional healers throughout the world on the efficacies of these plants have. Acetone gave the best results with these plants as compared to alcohol and water. The active components of these plants as antibacterial formulations have shown justified results and possibly presented a best resulting product that could be of highly value in preventing such enteric ailments. These products should be labeled with respect to the names of the active components these plants have and probably present directions for their dosage. Further improvements could also be presented in the terms of formulations of these products like emulsions or suspensions that have the ability to reduce the daily dosage of these enteric ailments and volumes of the products.

Inadequacies in Hospital Waste and Sewerage Management in Chattogram, Bangladesh: Exploring Environmental and Occupational Health Hazards

Bangladesh has been grappling with the issues of improper hospital waste management. To reflect the inadequacies in existing management practices and the potential implications on the environment and health, this study evaluated the Knowledge, Attitude, and Practice (KAP) of doctors and nurses in a private and a public hospital in Chattogram city via a structured questionnaire survey. At the public hospital, 20.4% of the doctors and 6% of the nurses had occupational illnesses, compared to 36% of the doctors and 26.5% of the nurses at the private hospital. At the public hospital, 67.8% of the nurses wore PPE during waste collection, compared to 17.7% in the private hospital. Hospital wastes and occupational safety are not properly dealt with in both hospitals. An inadequacy was observed in the knowledge of hospital waste management among healthcare workers. The route of hospital wastes from the sources to the end destination was also traced via interviews and focus group discussions, which revealed that disposal practices of the hospital solid waste were environmentally unsustainable. In attempts to show opportunities for environmental and health risks from the hospital wastewater, this study also investigated the quality of the wastewater and tested it for the presence of resistant enteric pathogens. E. coli and S. aureus from both hospitals showed resistance against some common antibiotics used in Bangladesh. The physicochemical properties of the samples were nearly compliant with the Bangladesh Water Quality Standards for hospital wastewater. While more robust sampling and water quality analysis are required, this study provides basic water quality indicators and scope for future research to understand the apparent significant negative impact on the environment and health.

Anti-virulence activity of polyphenolic fraction isolated from Kombucha against Vibrio cholerae

The use of traditional foods and beverages or their bioactive compounds as anti-virulence agents is a new alternative method to overcome the increased global emergence of antimicrobial resistance in enteric pathogens. In the present study, we investigated the anti-virulence activity of a polyphenolic fraction previously isolated from Kombucha, a 14-day fermented beverage of sugared black tea, against Vibrio cholerae O1. The isolated fraction was mainly composed of the polyphenols catechin and isorhamnetin. The fraction, the individual polyphenols and the combination of the individual polyphenols significantly inhibited bacterial swarming motility and expression of flagellar regulatory genes motY and flaC, even at sub-inhibitory concentrations. The polyphenolic compounds also decreased bacterial protease secretion and mucin penetration in vitro. In vivo study revealed that the polyphenolic fraction significantly inhibited V. cholerae induced fluid accumulation in the rabbit ileal loop model and intestinal colonization in suckling mice model. Therefore, the anti-virulence activity of the Kombucha polyphenolic fraction involved inhibition of motility and protease secretion of V. cholerae, thus preventing bacterial penetration through the mucin layer as well as fluid accumulation and bacterial colonization in the intestinal epithelial cells. The overall results implied that Kombucha might be considered as a potential alternative source of anti-virulence polyphenols against V. cholerae. To the best of our knowledge, this is the first report on the anti-virulence activity of Kombucha, mostly attributed to its polyphenolic content.

Characterization of Escherichia coli possessing the locus of heat resistance isolated from human cases of acute gastroenteritis

The purpose of this study was to identify Escherichia coli isolates obtained from patients experiencing acute gastroenteritis that possess the locus of heat resistance (LHR) and characterize their heat resistance upon exposure to temperatures of 60 °C and 71 °C. From a collection of 613 clinical E. coli strains, 3 heat resistant E. coli isolates were identified. Two of the 3 isolates were stx1 positive; no isolates possessed stx2 as determined by qPCR. D60-values of heat resistant isolates all exceeded 10.20 min with one isolate's D60-values ranging from 20.46 to 72.47 min. The presence of 4% additional NaCl significantly increased D60-values of 2 clinical isolates. Cell reductions of heat resistant isolates in ground beef patties grilled to 60 °C and 71 °C remained above 2.8 and 4.9 log CFU/mL, respectively, compared to reductions of 6.1 log CFU/mL and greater in heat sensitive E. coli. Constitutive expression of novel Clp protease ClpK, encoded on open reading frame 3 of the LHR, was identified in all heat resistant isolates by SDS-PAGE and peptide mass fingerprinting. This data is the first to report heat resistant E. coli possessing the LHR involved in clinical infection, highlighting the potential threat of heat resistant enteric pathogens on food safety.

Nickel chelation therapy as an approach to combat multi-drug resistant enteric pathogens

The nickel (Ni)-specific chelator dimethylglyoxime (DMG) has been used for many years to detect, quantitate or decrease Ni levels in various environments. Addition of DMG at millimolar levels has a bacteriostatic effect on some enteric pathogens, including multidrug resistant (MDR) strains of Salmonella Typhimurium and Klebsiella pneumoniae. DMG inhibited activity of two Ni-containing enzymes, Salmonella hydrogenase and Klebsiella urease. Oral delivery of nontoxic levels of DMG to mice previously inoculated with S. Typhimurium led to a 50% survival rate, while 100% of infected mice in the no-DMG control group succumbed to salmonellosis. Pathogen colonization numbers from livers and spleens of mice were 10- fold reduced by DMG treatment of the Salmonella-infected mice. Using Nuclear Magnetic Resonance, we were able to detect DMG in the livers of DMG-(orally) treated mice. Inoculation of Galleria mellonella (wax moth) larvae with DMG prior to injection of either MDR K. pneumoniae or MDR S. Typhimurium led to 40% and 60% survival, respectively, compared to 100% mortality of larvae infected with either pathogen, but without prior DMG administration. Our results suggest that DMG-mediated Ni-chelation could provide a novel approach to combat enteric pathogens, including recalcitrant multi-drug resistant strains.

Identification of Widespread Antibiotic Exposure in Patients With Cholera Correlates With Clinically Relevant Microbiota Changes.

BackgroundA first step to combating antimicrobial resistance in enteric pathogens is to establish an objective assessment of antibiotic exposure. Our goal was to develop and evaluate a liquid chromatography–ion trap mass spectrometry (LC/MS) method to determine antibiotic exposure in patients with cholera.MethodsA priority list for targeted LC/MS was generated from medication-vendor surveys in Bangladesh. A study of patients with and those without cholera was conducted to collect and analyze paired urine and stool samples.ResultsAmong 845 patients, 11% (90) were Vibrio cholerae positive; among these 90 patients, analysis of stool specimens revealed ≥1 antibiotic in 86% and ≥2 antibiotics in 52%. Among 44 patients with cholera and paired urine and stool specimens, ≥1 antibiotic was detected in 98% and ≥2 antibiotics were detected in 84%, despite 55% self-reporting medication use. Compared with LC/MS, a low-cost antimicrobial detection bioassay lacked a sufficient negative predictive value (10%; 95% confidence interval, 6%–16%). Detection of guideline-recommended antibiotics in stool specimens did (for azithromycin; P = .040) and did not (for ciprofloxacin) correlate with V. cholerae suppression. A nonrecommended antibiotic (metronidazole) was associated with decreases in anaerobes (ie, Prevotella organisms; P < .001).ConclusionThese findings suggest that there may be no true negative control group when attempting to account for antibiotic exposure in settings like those in this study.

Molecular Insights into Antimicrobial Resistance Traits of Multidrug Resistant Enteric Pathogens isolated from India

Emergence of antimicrobial resistant Gram-negative bacteria has created a serious global health crisis and threatens the effectiveness of most, if not all, antibiotics commonly used to prevent and treat bacterial infections. There is a dearth of detailed studies on the prevalence of antimicrobial resistance (AMR) patterns in India. Here, we have isolated and examined AMR patterns of 654 enteric pathogens and investigated complete genome sequences of isolates from six representative genera, which in aggregate encode resistance against 22 antibiotics representing nine distinct drug classes. This study revealed that ~97% isolates are resistant against ≥2 antibiotics, ~24% isolates are resistant against ≥10 antibiotics and ~3% isolates are resistant against ≥15 antibiotics. Analyses of whole genome sequences of six extensive drug resistant enteric pathogens revealed presence of multiple mobile genetic elements, which are physically linked with resistance traits. These elements are therefore appearing to be responsible for disseminating drug resistance among bacteria through horizontal gene transfer. The present study provides insights into the linkages between the resistance patterns to certain antibiotics and their usage in India. The findings would be useful to understand the genetics of resistance traits and severity of and difficulty in tackling AMR enteric pathogens.

Impact of urban contamination of the La Paz River basin on thermotolerant coliform density and occurrence of multiple antibiotic resistant enteric pathogens in river water, irrigated soil and fresh vegetables.

La Paz River in Andean highlands is heavily polluted with urban run-off and further contaminates agricultural lowlands and downstream waters at the Amazon watershed. Agricultural produce at this region is the main source of vegetables for the major Andean cities of La Paz and El Alto. We conducted a 1 year study, to evaluate microbial quality parameters and occurrence of multiple enteropathogenic bacteria (Enterohemorrhagic E. coli—EHEC, Enteroinvasive E. coli or Shigella—EIEC/Shigella, Enteroaggregative E. coli—EAEC, Enteropathogenic E. coli—EPEC Enterotoxigenic E. coli—ETEC and Salmonella) and its resistance to 11 antibiotics. Four sampling locations were selected: a fresh mountain water reservoir (un-impacted, site 1) and downstream sites receiving wastewater discharges (impacted, sites 2–4). River water (sites 1–4, N = 48), and soil and vegetable samples (site 3, N = 24) were collected during dry (April–September) and rainy seasons (October–March). Throughout the study, thermotolerant coliform density values at impacted sites greatly exceeded the guidelines for recreational and agricultural water uses. Seasonal differences were found for thermotolerant coliform density during dry season in water samples nearby a populated and hospital compound area. In contrast to the un-impacted site, where none of the tested enteropathogens were found, 100 % of surface water, 83 % of soil and 67 % of vegetable samples at impacted sites, were contaminated with at least one enteropathogen, being ETEC and Salmonella the most frequently found. ETEC isolates displayed different patterns of toxin genes among sites. The occurrence of enteropathogens was associated with the thermotolerant coliform density. At impacted sites, multiple enteropathogens were frequently found during rainy season. Among isolated enteropathogens, 50 % were resistant to at least two antibiotics, with resistance to ampicillin, nalidixic acid, trimethoprim–sulfamethoxazole and tetracycline commonly present. Moreover, some Salmonella isolates were distinguished by their multi-resistance to ≥8 antibiotics, within soil and vegetable samples. Overall, this study demonstrates that La Paz River—an affluent of the Amazon macrobasin—is heavily polluted along the year with a high density of thermotolerant coliforms and is a reservoir of multiple antibiotic resistant enteropathogens, present in river water, soil and vegetables. These data highlight health risk associated with food and waterborne diseases at the region.

Emerging antibiotic resistant enteric bacterial flora among food animals in Abeokuta, Nigeria

Bacterial resistance to antibiotic in food animals is an emerging public health concern as a result of increasing multi-resistant bacteria found in Abeokuta. Therefore, occurrence rate and resistant profile of the emerging enteric pathogens were determined in food animals in Abeokuta, Nigeria. Fecal and rectal samples of 82 were randomly collected from food animals such as sheep (30), chicken (37) and pigs (15) in three major farms located in Abeokuta, Nigeria. Enteric bacteria isolates obtained were cultured and identified according to standard protocol. Antibiotic susceptibility testing was performed by disc diffusion method and standard micro-tube dilution assay and resistance profile was carried out. Among the food animals surveyed for resistant enteric pathogens, 46% and 36% were chicken and sheep respectively while 18% were pigs. Complete resistance of 100% was shown by all the enteric bacteria obtained to metronidazole, tetracycline and penicillin while highest rate of Proteus mirabilis (33.5%) and Escherichia coli (20.1%) were multi resistant strains. Uncontrolled use of antimicrobial agents in food animals is shown to be associated with increasing emergence of antimicrobial resistance in food-borne pathogens which could enhance treatment failure and increase morbidity or death among the populace.

Acute Traveler’s Diarrhea: Initial Treatment

Diarrhea is the most common health issue affecting travelers to destinations across the world. This paper reviews the options for initial treatment of acute traveler’s diarrhea (TD). Its prevention, including but not limited to vaccines and safe travel and eating habits, is an important consideration but is beyond the scope of this paper. Treatment of TD has three arms: volume repletion, antibiotics, and antimotility/antisecretory agents. Patients should be advised to continue a diet that they can tolerate and maintain adequate fluid intake. In most cases, neither oral rehydration therapy nor dietary restrictions are likely to provide significant benefit. As yet, there is no evidence to support probiotic use for treatment of this type of diarrhea. Given that bacteria are the most frequent cause of TD, adult patients with moderate to severe disease should be treated empirically with a short course of antibiotics. In many instances, these will be prescribed pre-travel with instructions for proper usage when typical symptoms occur while abroad. However, such travelers should be advised to see a physician or seek emergency treatment if symptoms are severe or persist beyond 3 days. Antibiotic selection must take into account the epidemiology of resistant enteric pathogens. Fluoroquinolones are usually effective, although resistance of Campylobacter to this class of drugs in South and Southeast Asia warrants azithromycin as first-line empiric therapy in travelers to those regions. One day of therapy is often sufficient but can be extended to 3 days. Rifaximin is an alternative in non-invasive disease only. The antimotility agent loperamide is safe and effective and should be considered as adjunctive therapy in most cases of TD and can similarly be prescribed pre-travel. In non-pregnant adults, bismuth subsalicylate can also provide some symptomatic relief. Where available, racecadotril may be a safe alternative in both adults and children, although never specifically studied in TD. In cases of severe symptoms, or those lasting longer than 3 days, the patient should be evaluated for non-bacterial etiologies as well as possible Clostridium difficile infection. Certain travelers are more vulnerable to severe complications related to TD. Children, particularly infants, may need more aggressive fluid resuscitation with oral rehydration therapy. Several of the antidiarrheal agents must be avoided. Elderly patients and those with impaired cardiovascular reserve or immune-deficient states are more prone to complications as well. Treatment recommendations also differ for pregnant women. We generally advise adult non-pregnant travelers to follow smart eating and drinking practices and to bring a supply of bismuth subsalicylate and loperamide. We also prescribe an empiric antibiotic course (ciprofloxacin or azithromycin for up to 3 days) that is to be used for moderate to severe cases of TD.

Microbial Contamination and Antibiotic Resistance in Enteric Pathogens Isolated from Cooked Foods Sold in Eateries in Ado-Ekiti, Nigeria

Background: There are indications that some ready-to-eat or street vended foods are of low microbial quality with varying degree of contaminations. The contaminants may include antibioticresistant bacteria that may further be spread through consumption of such foods which has epidemiological and public health implications. This study therefore, was aimed at investigating the microbial quality of ready-to-eat cooked foods sold in eateries in Ado-Ekiti, Nigeria and to determine the susceptibility of the isolates to antibiotics. Methods: We evaluated bacterial contamination of ready-to-eat cooked foods using total bacteria plate counts (TPC) and total coliform counts (TCC). Susceptibility of isolates to antibiotics was tested using the disc diffusion method. Results: The overall mean TPC and TCC of cooked food samples ranged from 4.961.01 log10 cfu/g to 5.340.06 log10 cfu/g for both. There was no significant difference (≤ 0.05) in the overall mean TPC and TCC of the various cooked food samples from the three categories of sampling sites. The cooked foods examined were contaminated with a total of 129 enteric bacterial species Original Research Article Oluyege and Famurewa; BMRJ, 6(4): 236-246, 2015; Article no.BMRJ.2015.076 237 belonging to 7 genera with E. coli (31.8%) being the most prevalent, followed by Klebsiella sp. (19.4%), Proteus sp. (17.1%), Salmonella (14.0%), Pseudomonas sp. (12.4%), Shigella sp. (3.8%) and Enterobacter sp. (1.6%) in that order. Resistance to antibiotics was very high (94.0%) and resistance to amoxicillin (89.1%) was the highest, and least to nalidixic acid (23.1%) while none of the isolates was resistant to ofloxacin. More than 50% of these isolates were resistant to six of the eight antibiotics tested and 26 different antibiotic resistance phenotypes were obtained. The most common phenotype observed was AMX/GEN/AUG. The results suggest that contaminated readyto-eat (RTE) food sold in eateries can be a major source of antibiotic-resistant organisms in the study area. Conclusion: Most of the food samples investigated was contaminated in varying degrees with pathogenic, opportunistic pathogenic bacteria and other bacterial indicators of contamination. There was an overall high rate of resistance to antibiotics with equally high rate of multiple antibiotic resistance (MAR) among the bacterial contaminants. This portent high risks of further spread of antibiotic resistance in the community and environment. Further study will hopefully help to determine the presence of resistance genes and or mode of resistance among the MAR organisms.

Identification and characterization of alkaline protease producing Bacillus firmus species EMBS023 by 16S rRNA gene sequencing.

Probiotic microorganisms are those which exert a positive exect on the growth of the host, when administered as a dietary mixture in an adequate amount. They form the best alternative to the use of antibiotics for controlling enteric diseases in poultry farm animals, especially in the light of the gruesome problems of development of antibiotic resistance in enteric pathogens and the contamination of poultry products with antibiotics. 16S rDNA sequencing which has gained wide popularity amongst microbiologists for the molecular characterization and identification of newly discovered isolates provides accurate identification of isolates down to the level of sub-species (strain). It's most important advantage over the traditional biochemical characterization methods are that it can provide an accurate identification of strains with atypical phenotypic characters as well. The following work is an application of 16S rRNA gene sequencing approach to identify a novel, alkaline protease producing bacteria, from poultry farm waste. The sample was collected from a local poultry farm in the Guntur district, Andhra Pradesh, India. Subsequently the sample was serially diluted and the aliquots were incubated for a suitable time period following which the suspected colony was subjected to 16S rDNA sequencing. The results showed the isolate to be a novel, high alkaline protease producing bacteria, which was named Bacillus firmus isolate EMBS023, after characterization the sequence of isolate was deposited in GenBank with accession number JN990980.

Distribution and antimicrobial resistance of enteric pathogens among Chinese pediatric diarrhea: A multicenter retrospective study (2008–2013)

Distribution and antimicrobial resistance of enteric pathogens among Chinese pediatric diarrhea: A multicenter retrospective study (2008–2013)

[Evolution of bacterial resistance to antibiotics in México, 1973-2013].

Bacterial resistance to antibiotics is a worldwide public health concern. Research priorities for the study and control of this emerging problem include country-wide surveillance. To review and comment on the contributions by Mexican investigators towards a greater understanding of the mechanisms of bacterial antibiotic resistance. A comprehensive search of the medical literature on Medline/PubMed between 1973 and July 2013 was performed. The contributions of Mexican investigators have included descriptions of resistance in enteric pathogens, such as Salmonella Typhi, publications on the production of extended spectrum beta-lactamases, metallo-beta-lactamases, and carbapenemases, resistance mechanisms of Pseudomonas aeruginosa , and the evolution of resistance in Gram-positive pathogens, including Streptococcus pneumoniae , Staphylococcus aureus , and Enterococcus spp. The Mexican literature on mechanisms of bacterial resistance is relevant for the development of plans to control the antibiotic resistance crisis.

IncA/C plasmids

Incompatibility group IncA/C plasmids are large, low copy, theta-replicating plasmids that have been described in the literature for over 40 years. However, they have only recently been intensively studied on the genomic level because of their associations with the emergence of multidrug resistance in enteric pathogens of humans and animals. These plasmids are unique among other enterobacterial plasmids in many aspects, including their modular structure and gene content. While the IncA/C plasmid genome structure has now been well defined, many questions remain pertaining to their basic biological mechanisms of dissemination and regulation. Here, we discuss the history of IncA/C plasmids in light of our recent understanding of their population distribution, genomics, and effects on host bacteria.

Gram-Negative Bacterial Resistance to Cephalosporins in Community-Acquired Infections in Turkey

Cephalosporins are widely used and trustworthy antibiotics in daily medical practice. Although antibacterial resistance has been reported in hospital wards, there are less data for community-acquired infections. In this study we investigated the cephalosporin susceptibility profiles of community-acquired Gram-negative bacteria isolates in Sivas Kizilay Medical Center (Turkey) between March 2002 and March 2003. In our study, 949 Escherichia coli, 165 Proteus spp., 97 Enterobacter spp., 24 Klebsiella sppand 84 Pseudomonas aeruginosastrains were evaluated. Cefepime seemed to be the most effective antibiotic against our community-acquired Gram-negative isolates. Resistance to this drug was 19.3% for P. aeruginosaand around 0-10.6% for enteric bacteria. Enteric pathogen resistance ranged between 44.3-100% for cefazolin, 25-51.9% for cefuroxime, 4.8-25.3% for ceftriaxone, 5.4-14.5% for ceftazidime. Resistance in enteric pathogens to gentamicin ranged between 5.8-15.4%, to amikacin between 3.8-6.25%, to ciprofloxacin between 6.7-20%. 8.1% of P. aeruginosawere resistant to ciprofloxacin. With these profiles the aminoglycosides and ciprofloxacin resemble highly effective cephalosporins like cefepime. On the contrary, first- and secondgeneration cephalosporins, trimethoprim-sulfamethoxazole, ampicillin and ampicillin-sulbactam are no longer used in probable Gram-negative bacterial infections in our region. Since treatment based on cephalosporins was less efficacious than expected in community-acquired infections, urgent measures are needed to limit antibacterial resistance outside of hospitals.

Water sources and environmental transmission of multiply resistant enteric bacteria in rural Bangladesh

The role of different water sources in the spread of multiply resistant enteric bacteria was investigated in rural Bangladesh. The prevalence of resistance to commonly used antimicrobial agents in the faecal flora of village children and the water quality and prevalence of resistance in village water sources were studied. Most of the children studied (81%) had multiply resistant faecal coliform bacteria, i.e. bacteria resistant to at least three antimicrobials. Although tubewells provided water with low faecal coliform counts, 62% of household storage pots contained water with moderate to high counts. Most of the storage pots (76%) and each of the river and pond sites tested contained multiply resistant isolates. Contamination of water within the household, and the widespread distribution of resistant coliforms in the environment, contribute to the high prevalence of multiply resistant enteric flora in the community. These findings are of importance in understanding the spread of multiply resistant enteric pathogens.