Standard Disk Diffusion Method Research Articles

Anti-Microbial Potential of Panacea (Nigella Sativa)

Background: In the existing scenario, increasing drug cost, toxic effects and drug resistance or the main motivating factors for researchers to exploit the natural bioactive sources for safe and natural therapeutic as an alternative to antibiotics. Objectives: The main objective of the study is to find out the antimicrobial potential, its spectrum and magnitude in N.sativa. Study Design: Experimental/in vitro study. Duration: September, 2016 – February, 2017. Settings: Different departments (of School of Pharmacy, Pathology and Bio-chemistry of UM & DC), The University of Faisalabad. Methodology: Antibiotics assay is performed by using the disc diffusion methods. N.sativa extracts are prepared and from these sensitivity discs are prepared. Standard size inoculum is also prepared. Then by using standard disc diffusion method the zones of inhibitions produced by N.sativa extracts are measured and recorded in mm and is compared with positive and negative controls. Results: Spice extract tested against test organisms revealed antimicrobial potency with diameter of zone of inhibition (27.17±0.98mm - 31.33±0.21mm) while positive control manifested zone of inhibition (19.33±0.21 - 29.17±0.17mm). Ethanol extracts prepared by Soxhlet apparatus showed better results compared with extracts prepared by simple maceration process. Furthermore, overall ethanol extracts showed better results compared with the aqueous extracts. Conclusion: This study revealed the presence of natural bioactive compound(s) in N.sativa with highly significant broad spectrum antibacterial potential, even against multi resistant pathogens.

Prevalence of multi-drug resistant Staphylococci isolated from surgical site infections

Surgical site infections are the most common post-operative infections even in hospitals with most modern facilities complications and standard protocols of pre-operative preparation and antibiotic prophylaxis.Staphylococci stay as our natural flora and yet sometimes threaten our life as tenacious pathogens. In addition to their ability to evade our immune system, the multi-drug resistance phenotype makes Staphylococci the most intractable pathogenic bacteria in the history of antibiotic chemotherapy. Staphylococci are among the leading causes of nosocomial infections such as surgical site infections. Increasing resistance to β-lactams and the glycopeptides complicates treatment of infections caused by Stahpylococci. The aim of this study is to investigate the antibiotic resistance profile of Staphylococci isolated from surgical site infection. Staphylococci isolates were identified morphologically, by Gram stain and biochemical tests. Antimicrobial susceptibility testing was done by the Kirby-Bauer standard disk diffusion method. One hundred Staphylococci isolates were recovered from one hundred and ninety samples isolated from surgical site infections. Staphylococcus aureus was the most predominant one. From 100 isolates, Staphylococcus aureus was found in 91 isolate and coagulase-negative Staphylococci (CoNS) in 9 isolates. Staphylococcus aureus isolates were highly resistant to tigecycline, oxacillin, ampicillin and ampicillin-sulbactam antibiotics. They showed intermediate resistance to daptomycin, amikacin, azithromycin, levofloxacin, clindamycin, sulfamethoxazole-trimethoprime, doxycycline and gatifloxacin, while they showed low resistance to vancomycin, linezolid and imipenem. On the other hand, CoNS isolates were highly resistant to doxycycline, oxacillin, ampicillin and ampicillin- sulbactam antibiotics. They showed intermediate resistance to daptomycin, levofloxacin, clindamycin, sulfamethoxazole-trimethoprime, gatifloxacin, vancomycin, tigecycline, linezolid and imipenem, while they showed low resistance to amikacin and complete sensitivity to azithromycin. Eighty four isolates were multi-drug resistant.Percentage of multi-drug resistant Staphylococci isolates were very high. This may be attributed to the misuse of antibiotics. To minimize resistance, strict antimicrobial prescription policy should be applied.

New Delhi Metallo-β-lactamase (NDM)-mediated Carbapenem-Resistant Pseudomonas aeruginosa Clinical Isolates in Sudan

Carbapenem resistance mediated by NDM is particularly gruesome as this carbapenemase can hydrolyze a wide range of β-lactam antibiotics.
 Aim: This study aims to detect NDM mediated carbapenem resistance in clinical isolates of Pseudomonas aeruginosa.
 Materials and Methods: 50 multi-drug resistant clinical urinary isolates of Pseudomonas aeruginosa from three major hospitals in Khartoum state Sudan; Khartoum Teaching Hospital, Medical Army Hospital and Omdurman teaching hospital, in period from July 2016 to September 2017, were investigated for carbapenem resistance using standard disc diffusion method and underwent real-time PCR to detect carbapenem resistance gene blaNDM. Data were analyzed using IBM SPSS.
 Results: 60% were positive for the blaNDM, 82% were resistant to Imipenem and 75% of the samples were resistant to Meropenem.
 Conclusion: The emergence of carbapenem resistance is a global problem that requires earnest attention. To make the suitable preventive measures, the emergence of these genes must be monitored closely. Our findings revealed that carbapenem-resistant due to the gene blaNDM is accounted for 60% of the cases, and due to lack of proper data documentation about the emergence of this gene in Sudan, these cases to the best of our knowledge are the first to be reported in Sudan.

Characterization of culturable airborne bacteria and antibiotic susceptibility profiles of indoor and immediate-outdoor environments of a research institute

Background:The study was conducted to determine the bacterial composition and antibiotic susceptibility profiles of a research institute at the University of Ghana where workers and students spend about 70-85% of their lives in indoor and immediate-outdoor environments. This is imperative as one-third of the recognized infectious diseases are transmitted through airborne-route. Furthermore, the increasing rate of bacterial antimicrobial resistance associated with such environments poses serious public health challenges.Methods:A total of 42 airborne samples were collected from eight major sites at the Department of Biochemistry, Cell and Molecular Biology (BCMB), using passive bacterial sampling techniques. Standard phenotypic microbiological procedures were used to characterize the isolates. Antibiotic susceptibility profiles were determined using standard disk diffusion method and guidelines of Clinical and Laboratory Standards Institute (CLSI).Results:Four groups of bacterial isolates were identified from the total samples collected with Gram positive bacilli as the most common. All the isolates showed resistance to beta lactam and sulfonamide classes of antibiotics with full resistance (100%) to ampicillin and penicillin. In total, seven different anti-biotypes were observed with the highest susceptibility displayed towards tetracycline and gentamycin. Significantly, the various air sampling sites of the institute indicated the presence of bacteria with the majority showing multiple antibiotics resistance.Conclusions:Although the recovery of bacteria from supposed sterile environments calls for attention, the observed low contamination rate as compared to the WHO standard suggests a minimum risk of exposure of students and workers to airborne microbial contamination.

Biodiversity and antibacterial screening of endophytic fungi isolated from Pelargonium sidoides

To investigate the biodiversity of endophytic fungi isolated from indigenous Pelargonium sidoides plants using morphological and molecular techniques and also screen isolates for antibacterial activities.In the present study, a total of 50 Pelargonium sidoides plants were collected and the roots were analysed for the presence of endophytic fungi. The fungi were initially sorted according to morphological characteristics. Fungal identities were further confirmed through amplification of sequences encoding Translation Elongation Factor-1α (TEF-1α) gene for Fusarium species and Internal Transcribed Spacer (ITS) regions for all other fungi. Fungi were screened for antibacterial activity by adopting the standard Kirby-Bauer agar disc diffusion method using a pathogenic Escherichia coli strain (Code from the collection) previously isolated from cattle. A total of 133 fungi belonging to 32 genera were successfully isolated and identified in the study based morphological analyses. Fungi belonging to the genus Penicillium were dominant (23%) among the isolates when compared with Fusarium species (12%) as well as Alternaria and Aspergillus that were detected at 11% respectively. Antibacterial agent producing data revealed that Aspergillus sp. (KM458796.1), Penicillium expansum (LC015096.1) and Aspergillus niger (KP172477.1) produced the strongest bactericidal activity against the E. coli strain with growth inhibition zone diameter data of 11mm, 5mm and 4mm respectively. To the best of our knowledge, this is the first study in which the diversity of fungi from Pelargonium sidoides has been assessed and the findings revealed that fungal diversity is directly related to their potential to produce bioactive compounds.

ANTIMICROBIAL SUSCEPTIBILITY TO SALMONELLA AND E.COLI ISOLATES ORIGINATED FROM BROILER CHICKENS IN LUXOR GOVERNORATE

Salmonellosis and colibacillosis are continuing serious problems facing poultry industry in Egypt. In this study, 300 different pooled broiler chickens organs samples as (trachea, lung, liver, heart, spleen, unabsorbed yolk sac and intestine) were collected from different apparently healthy and sick broiler flocks in different localities of Luxor governorate during (2015 and 2016). The examined broiler flocks were suffering from various health problems developed during the final two weeks of the growing period, resulting in increased mortality and condemnation losses. Bacterial isolation was done by using standard method of isolation and identification. The results showed that 92 out of 300 broiler organs samples were positive for Salmonella spp. (30.66%) while 161 out of 300 were E.coli positive (53.66%). The present study showed that the main Salmonella spp. isolates were (S. Typhimurium (24%), the both of S. Enteritidis, S. Anatum were (21.7%) and S. Kentucky (19.56%), S. Bargny and S. Molade (3.26%) then S. Newport, S. Ingada and S. Agona their percentage were (2.17%) respectively, while 8 serotypes of E.coli were obtained with the following serological identification O78 (44%), O1:H7 (17.39%), O91:H21 (15.52%), O128:H2 (13%) and other E.coli serotypes were identified as (O2:H6, O26:H11, O55:H7, O146:H21) their percentage was (1:3%). Bacterial strains were tested against 21 antibacterial agents using the standard disk diffusion method on Muller and Hinton’s Agar medium. The results were recorded that most of Salmonella spp were highly resistant to (Oxytetracycline, Doxycycline, Tetracycline then Enrofloxacin, Sulphamethoxazole) and were sensitive to (Gentamycin, colistinsulphate and Ceftiofur). While most of E.coli isolates were resistant to Neomycin and Streptomycin and were sensitive to Ceftiofur then Colistinsulphate.

Isolation, molecular and phenotypic characterization of Cronobacter spp. in ready-to-eat salads and foods from Japanese cuisine commercialized in Brazil

The aim of this study was to detect Cronobacter from 30 samples of ready-to-eat (RTE) salads and 30 foods from Japanese cuisine as commercially available in Brazil. The detection of Cronobacter was as according to the ISO standard 22964:2017. The isolates were phenotypically characterized by Vitek 2.0 and the antibiotic susceptibility profile was determined using the standardized agar disc diffusion method. Molecular characterization was accomplished by real-time PCR targeting dnaG gene, multiplex-PCR targeting cgcA gene, and fusA allele sequencing. Twenty-seven samples (45.0%) contained Cronobacter, 14 (23.3%) samples of foods from Japanese cuisine and 13 (21.7%) samples of RTE salads. Twenty-nine unique Cronobacter isolates were selected from the 27 positive samples and were identified as C. sakazakii (n = 18), C. malonaticus (n = 8), and C. dublinensis (n = 3). A high genetic diversity was observed, with 29 Cronobacter strains being assigned to 11 different fusA alleles, a ratio of 2.6 strains by fusA allele was found. The cgcA multiplex-PCR failed to identify many of the Cronobacter isolates at the species level. Four (13.8%) Cronobacter isolates were resistant to one or more antibiotics tested (n = 12). The presence of Cronobacter in RTE foods could be a potential threat to human health and highlights the need for high levels of hygiene, particularly when preparing food for elderly, immunosuppressed persons or adults with prior underlying pathology. Epidemiological surveillance agencies should be aware of the risk that these RTE foods may represent, for these groups.

Fabrication of novel dental nanocomposites and investigation their physicochemical and biological properties

This article evaluates physicochemical, mechanical, and biological properties of a series of novel dental nanocomposites that fabricated from multifunctional methacrylate-based dental monomers, triethyleneglycol dimethacrylate (TEGDMA) monomer, and modified silica nanoparticles (SiO2 NPs). The antibacterial activities of the monomers were investigated against lactobacillus plantarum by standard agar disk diffusion method. The cytotoxicity characteristics of the monomers and fabricated nanocomposites were evaluated by MTT and trypan blue cell viability tests, respectively against NIH3T3 cell line. In addition, the mechanical properties, as well as physicochemical characteristics including water sorption, sol fraction, and double bond conversion were also investigated. According to the results, the formulated nanocomposites have potential to apply as dental nanocomposites mainly due to their acceptable physicochemical, mechanical and biological characteristics.

English

Extended spectrum beta-lactamases (ESBLs) are enzymes that are now becoming major sources of resistance to β-lactamase antibiotics more especially in enteric bacteria such as Klebsiella pneumoniae, P. aeruginosa and Escherichia coli. Increase in the frequency of the β-lactam resistance in bacteria has become a serious threat for treating bacterial infections caused by enterobacteriaceae. This study aims to determine the prevalence of ESBLs producers among enteric Gram negative bacteria isolated from patients in OAUTHC, Ile-Ife, Osun State. The subject used in this study involved patients presenting with evidence of hospital infections. The collected sputum specimens were processed for the isolation and identification of Gram negative bacilli. Resistance of the isolates to different antibiotics tested was determined using the standard disc diffusion method of Kirby-Bauer. Phenotypic and confirmatory test of the isolates were done for ESBL production using double disc synergy test (DDST) on Mueller Hinton agar according to CLSI 2013 guidelines. Results reveal that the highest occurrence of bacteria was recovered in Klebsiella species (35%), followed by Enterobacter sp. (13%), P. aeruginosa (10%), Escherichia coli and Salmonella sp. (7%) while the least occurs in Proteus sp. All the isolates were 100% resistance to class piperacillin, 76.6% to beta-lactamase inhibitor and 52% resistance to cephalosporins while they were susceptible to carbapenems, nitrofurans, and fluoroquinolones. The prevalence of ESBLs producing isolates was 51.1% while non-ESBL producing strains were 48.8%. Therefore, it can be concluded that extended spectrum beta lactamases are gradually increasing in Nigeria with co-resistance to some other classes of antibiotics which is very alarming. There is a limited number of drugs sensitivity for these bacteria and the drug of choice is imipenem, ciprofloxacin and ofloxacin. Key words: Multidrug resistance, extended spectrum beta-lactamases (ESBLs), Gram negative bacteria

Frequency of antimicrobial resistance and integron gene cassettes in Escherichia coli isolated from giant pandas (Ailuropoda melanoleuca) in China

Escherichia coli (E. coli) is considered as a common opportunistic pathogen, which causes seriously intestinal infections to giant pandas (Ailuropoda melanoleuca) and other animals. The aim of this investigation was to characterize the antimicrobial resistance and integron gene cassettes in E. coli isolated from the faeces of giant pandas in China. A total of 89 E. coli were isolated, after diagnosis of isolates and genomes were extracted. All the isolates were screened for the presence of related drug-resistance genes and integron gene cassettes through the Polymerase Chain Reaction (PCR) and sequencing. In addition, antimicrobial resistance testing was performed according to the standard disk diffusion method (CLSI 2013). The results demonstrated that all the isolates were multi-drug resistance (MDR). High resistance proportions of the E. coli isolates were to streptomycin (93%), cefazolin (90%), amikacin (75%), tetracycline (65%), ampicillin (62%), cefotaxime and trimethoprim-sulfamethoxazole (54%, each). With respect to the various resistance genes; blaCTX-M, sul1, ant (3′)-Ia, tetA, qnrB, tetE, floR, aac (6′)-Ib, sul2, rmtA, cmlA, rmtB and tetC were identified with the respective frequencies of 44%, 45%, 38%, 37%, 35%, 27%, 26%, 20%, 18%, 15%, 10%, 7% and 4%. None of the isolates was positive for qnrA and cfr genes. Moreover, a further investigation of integron revealed that the emergence of class 1 and 2 integrons were in 47% and 8% isolates, respectively. While class 3 integron was not screened. Six types of containing in class 1 integron specific gene cassettes (dfrA12-orfF-aadA2, dfrA17-aadA5, aadA1, aadA5, dfrA1 and dfrA7) were identified. However, only one gene cassette (dfrA1-sat2-aadA1) was detected in class 2 integron. These finding emphasize that a high level of E. coli isolates harbored antibiotics resistance and integron gene cassettes, which may bring so many potential threats to the health of giant pandas.

Prevalence of asymptomatic bacteriuria among antenatal women and its effects on maternal and perinatal outcome in northern Andhra Pradesh population

Background: The pregnant women are more commonly affected with asymptomatic bacteriuria (ASB) than non-pregnant women and its progression could lead to adverse maternal and perinatal outcomes. The study was designed with an aim to know the prevalence of ASB and its effects on maternal and perinatal outcome.Methods: In this prospective study, 300 antenatal women attending Anil Neerukonda Hospital were screened for ASB. Urine culture was performed using standardized Kirby-Bauer disc diffusion method on blood agar, Mac Conkey’s agar for antibiotic sensitivity testing. The screened antenatal women were divided into two subgroups viz. asymptomatic bacteriuria positive (Group I) and asymptomatic bacteriuria negative (Group II) depending on the culture study and were followed till delivery for maternal and perinatal outcomes.Results: The prevalence of ASB was 11.33%. Out of 34 cases of ASB positive, 8 cases (23.5%) were delivered with birth weight <2500 grams as compared to 11 cases (4.1%) in unexposed cases (RR 5.68, 95% CI; 2.46-13.15; p<0.05). Preterm low birth was noticed in 5 (14.7%) cases of ASB positive pregnant women with compared to unexposed cases (RR 1.5, 95% CI; 0.61-3.65, p=0.36). Regarding maternal outcomes, premature labour was observed in 8 cases (23.5%) of ASB exposed women whereas 22 (8.3%) in non-exposed cases (RR 2.84, 95% CI; 1.37-5.88, p=0.004). A significant number of women have developed hypertension (17.6%) and preeclampsia (8.8%) in ASB positive cases as compared to ASB negative cases (4.9% and 2.3% respectively).Conclusions: The prevalence of ASB was 11.33% in the present study. As one third of the cases were identified in early and late trimesters, regular and trimester wise screening need to be incorporated in routine antenatal screening for safe motherhood and new born health.

Bacterial isolates and their antimicrobial susceptibility patterns among pediatric patients with urinary tract infections.

Urinary tract infection is a common pediatric problem with the potential to produce long-term morbidity. Therefore, appropriate diagnosis and prompt treatment is required. However, studies about magnitude of uropathogenicity and antimicrobial resistance pattern of pediatric urinary tract infection (UTI) are lacking in resource limited countries including Ethiopia. This study was aimed to determine bacterial isolates, antimicrobial susceptibility pattern among pediatric patients with UTI. A cross- sectional study was conducted. Pathogenic bacterial isolates were identified by culture and biochemical methods following standard procedures. Antimicrobial susceptibility testing of the isolates for commonly used antibiotics was done using the standard disc diffusion method on Muller Hinton agar. Associations between dependent and independent variables were measured using chi-square test and within 95% confidence interval. P values <0.05 were considered as statistically significant. A total of 310 pediatric patients were included in the study, and 82 (26.45%) bacterial isolates were detected. Gram- negative bacteria were predominant etiologic agents of UTI in this study. E. coli was the most frequently occurring pathogen (n=45; 54.88%) followed by S. aureus and P.aeruginosa (n=8; 9.75% for both), P. vulgaris, P.aeruginosa (n=4; 4.88%, for both) and Enterococcus species (n=3; 3.66%). All K. pneumoniae, P. mirabilis, and K. ozanae straines were 100% resistance to ampicillin, followed by P. aeruginosa (87.5%) and E. coli (69%). While all Gram- positive bacterial isolates were 100% sensitive to ciprofloxacin. Malnutrition, history of catherization and previous history of UTI were independently associated with UTI (p=0.000). There was a high prevalence of uropathogenic bacteria and drug resistance particularly to ampicillin (72%) and tetracycline (37.80%). This condition indicates that antibiotic selection should be based on knowledge of the local prevalence of bacterial organisms and antibiotic sensitivities rather than empirical treatment.

The use of macro- and microalgae as functional ingredients in diets for meagre (Argyrosomus regius, Asso 1801)

The use of macro- and microalgae as functional ingredients in diets for meagre (Argyrosomus regius, Asso 1801)

Antibacterial Activity of Novel Strains of Bacteriophages: An Experimental Approach.

The evolution of antibiotic resistance in bacteria has increased research in the development of alternative therapies to conventional drugs. In this study, isolated phages were characterized and antibacterial activity was determined by standard agar disc diffusion method. The phages showed maximum propagation at 37°C to 40°C and highest viability at pH 7. Sugars influenced the bacteriophage viability. Sodium chloride decreased the phage propagation. Calcium chloride and magnesium chloride increased the phage propagation up to a certain limit. SDS-PAGE analysis confirmed the presence of protein cover and showed the various bands ranging from 10 to 200 kDa. Nucleic acid analysis confirmed the presence of RNA with a size of approximately 20 kb. Transmission electron microscopy indicated that the phages belong to Siphoviridae, Leviviridae, and Podoviridae families.

Extended-Spectrum beta-lactamase production and antimicrobial susceptibility pattern of uropathogens in a Tertiary Hospital in Northwestern Nigeria

Background: Globally, there is a changing trend in the antibiotic susceptibility pattern of Gram-negative uropathogens to the conventional drugs used in the treatment of urinary tract infections due to the production of extended-spectrum beta-lactamases (ESBLs). Aim: This study aimed to determine ESBL production and antimicrobial susceptibility pattern in uropathogens. Materials and Methods: Five hundred urine samples submitted to the Medical Microbiology Department of Ahmadu Bello University Teaching Hospital from January to June 2012 were analyzed by conventional methods. Modified standardized Kirby-Bauer disc diffusion method was used for antimicrobial susceptibility testing. ESBL production by Escherichia coli and Klebsiella pneumoniae isolates was screened for using the Clinical and Laboratory Standards Institute guidelines 2012 and confirmed by the double-disc synergy tests. Results: Five hundred samples were analyzed. Of these, a total of 175 Gram-negative isolates were obtained. Isolation rates were E. coli – 56%, K. pneumoniae – 20%, Proteus mirabilis – 16%, and Pseudomonas aeruginosa – 4%. ESBL production was observed in 34.3% of all the isolates. Fifty percent (50%) of E. coli and 40% of K. pneumoniae were identified as ESBL producers and were found to be resistant to multiple antimicrobial agents. Imipenem and nitrofurantoin had sensitivity of 100% and 70%, respectively, while susceptibility to ciprofloxacin and gentamicin was low at 35% and 30%, respectively, although 96% sensitivity was observed with amikacin. ESBL producers and nonproducers showed a high level of resistance of over 95% to ampicillin, amoxycillin, and trimethoprim-sulfamethoxazole. Conclusion: This study found a high rate of ESBL production (34.4%) among uropathogens with multidrug resistance. Clinical microbiology laboratories should routinely incorporate ESBL detection methods in their laboratory procedures for continuous surveillance of multidrug-resistant isolates and antibiograms to guide empirical therapy.

Investigation of the Antidiarrheal and Antimicrobial Activities of 80% Methanolic Leaf Extract of Discopodium Penninervum (Hochst.).

Diarrhea is a major health problem throughout the world and it has become more problematic in developing countries like Ethiopia. People, in several parts of the world, use different traditional medicines for treating diarrhea and it has been reported that the roots, leaves, and flowers of various species are used for the same purpose. In Ethiopia, for instance, Discopodium Penninervum is used for the treatment of diarrhea and also to control infection. The aim of the present study was, therefore, to evaluate the in vivo antidiarrheal and in vitro antimicrobial effect of Discopodium Penninervum in mice. For the antimicrobial activity test, four standard bacteria and disc diffusion method were used, while for antidiarrheal experiment, animals had been used, which were divided into 5 groups. The first group served as negative control and was administered with vehicle (0.2-0.3ml of distilled water). Groups two (D100), three (D200), and four (D400) were administered 100, 200, and 400 mg/kg of the extract, respectively. Group five served as positive control group and was administered with either loperamide (3mg/kg) for castor oil induced diarrhea and castor oil induced enteropooling diarrhea models or atropine (1mg/kg) for charcoal meal test. Safety study was performed using a standard acute toxicity study procedure. The effect of the extract on castor oil induced diarrheal drops, onset of diarrhea, weight of faeces, small intestinal fluid accumulation, and intestinal motility was measured and analyzed using one-way ANOVA. Preliminary phytochemical screening of the leaves powder of the plant indicated the presence of various components. Inhibition of castor oil induced diarrhea was observed at all tested doses. It can be concluded that crude extracts of Discopodium Penninervum showed strong activities against diarrhea indicating that it contains some chemical constituents that possibly lead to antidiarrheal drug development.

Antimicrobial susceptibility of Neisseria gonorrhoeae isolates in Vientiane, Lao PDR.

The aim of this study was to determine the antimicrobial susceptibility of Neisseria gonorrhoeae isolates in the Lao People's Democratic Republic (Laos). A total of 165 gonococcal isolates (1.3%) were obtained from 12 281 genital samples routinely submitted to a diagnostic laboratory in Vientiane, Laos, between 2011 and 2015. Susceptibility to five antibiotics was determined by the standard disk diffusion method for 158 of the isolates. Rates of resistance to penicillin (by β-lactamase production), tetracycline and ciprofloxacin were 89.9%, 99.4% and 84.8%, respectively. All isolates were susceptible to ceftriaxone and spectinomycin. The situation in Laos is similar to that in neighbouring countries; this fortunately means that the latest Lao national guidelines for treating gonorrhoea should still be effective.

Antibiotic susceptibility of methicillin-resistant staphylococci (MRS) of food origin: A comparison of agar disc diffusion method and a commercially available miniaturized test

Methicillin-resistant staphylococci (MRS) are a major concern to public and animal health. Thirty MRS (Staphylococcus aureus, S. cohnii, S. epidermidis, S. haemolyticus, S. hominis, S. lentus, S. lugdunensis, S. sciuri, and S. xylosus) isolates from meat and poultry preparations were tested for antimicrobial susceptibility to 11 antimicrobials (belonging to seven different categories) of clinical significance using both the standard agar disc diffusion method and a commercially available miniaturized system (Sensi Test Gram-positive). It is worth stressing that 16 isolates (53.33%) exhibited an extensively drug-resistant phenotype (XDR). The average number of resistances per strain was 4.67. These results suggest that retail meat and poultry preparations are a likely vehicle for the transmission of multi-drug resistant MRS. Resistance to erythromycin was the commonest finding (76.67% of strains), followed by tobramycin, ceftazidime (66.67%), ciprofloxacin (56.67%) and fosfomycin (53.33%). An agreement (kappa coefficient) of 0.64 was found between the two testing methods. Using the agar disc diffusion as the reference method, the sensitivity, specificity and accuracy of the miniaturized test were 98.44%, 69.44% and 83.33%, respectively. Most discrepancies between the two methods were due to isolates that were susceptible according to the disc diffusion method but resistant according to the miniaturized test (false positives).

Prevalence and antibiotic resistance of Pseudomonas aeruginosa in water samples in central Italy and molecular characterization of oprD in imipenem resistant isolates.

ScopeThis study aimed to analyse the prevalence, antibiotic resistance and genetic relatedness of P. aeruginosa isolates obtained from potable and recreational water samples (n. 8,351) collected from different settings (swimming pools, n. 207; healthcare facilities, n 1,684; accommodation facilities, n. 1,518; municipal waterworks, n. 4,500; residential buildings, n. 235). Possible mechanisms underlying resistance to imipenem, with particular focus on those involving oprD-based uptake, were also explored.Methods and resultsIsolation and identification of Pseudomonas aeruginosa was performed according to the standardized procedure UNI EN ISO 16266:2008 followed by PCR confirmation. Antibiotic Susceptibility testing was conducted according to EUCAST standardized disk diffusion method. Genetic relatedness of strains was carried out by RAPD. The sequence of the oprD gene was analyzed by standard method. Fifty-three samples (0.63%) were positive for P. aeruginosa, of which 10/207 (4.83%) were from swimming pools. Five isolates (9.43%) were resistant to imipenem, one to Ticarcillin + Clavulanate, one to both Piperacillin and Ticarcillin + Clavulanate. The highest isolation rate of imipenem resistant P. aeruginosa was observed in swimming pool water. Identical RAPD profiles were found in isolates from the same location in the same year or even in different years.ConclusionsImipenem resistant strains were identified as carbapenemase-negative and resistance has been associated with inactivating mutations within the oprD gene, with a concomitant loss of porin. RAPD results proved that a water system can remain colonized by one strain for long periods and the contamination may be difficult to eradicate.This study has revealed the presence of P. aeruginosa in different water samples, including resistant strains, especially in swimming pools, and confirmed the role of porins as a contributing factor in carbapenem resistance in Gram-negative bacteria.

Urinary pathogenic bacterial profile, antibiogram of isolates and associated risk factors among pregnant women in Ambo town, Central Ethiopia: a cross-sectional study

BackgroundUrinary tract infection (UTI) is a well-known bacterial infection posing serious health problem in pregnant women. A study was conducted in pregnant women with the objectives of estimating prevalence of UTI, determining antibiogram of the bacterial isolates and assessment of the potential risk factors associated with UTI.MethodsA cross-sectional study design was used to collect 300 mid-stream urine samples from pregnant women from March 2016 to December, 2016. Samples were inoculated into Cysteine Lactose Electrolyte Deficient medium (CLED). Colonies from CLED were subcultured onto MacConkey and Blood agar plates. A standard agar disc diffusion method was used to determine antimicrobial susceptibility. Chi-square (X2) test & logistic regression were used to show associations between UTI and explanatory variables & identify the predictors of UTI, respectively.ResultsThe age of pregnant women enrolled in this study ranges from 16 to 46 years (mean ± standard deviation = 25 ± 4.7 years).The overall prevalence of UTI in pregnant women was 18.7% (95% confidence interval [CI]: 14.4–23.54%).The prevalence of symptomatic and asymptomatic UTI was 20.4% (95% CI: 13.09–29.46%) and 17.8% (95% CI: 12.70–23.83%) respectively. The predominant bacteria identified were E. coli (46.4%), S. aureus (14.3%), coagulase negative Staphylococci [CoNS] (14.3%) and Proteus species (10.6%). Majority of Gram-negative bacteria isolates were resistant to ampicillin (70%), ceftriaxon (66%), gentamicin (68%) and nitrofurantoin (64%) while 75–100% of the Gram positive isolates were resistance to ampicillin. Multiple drug resistance was observed in all of the isolates. Multivariable logistic regression revealed that the odds of acquiring UTI was 4.78 times higher in pregnant women earning monthly income of ≤500 Ethiopian Birr (21.18 USD) as compared to those earning monthly income >2001 Ethiopian Birr [84.79 USD] (P = 0.046). Similarly, the risk of UTI was higher in those who eat raw meat (OR = 2.04, 95% CI: 1.09, 3.83, P = 0.026) and had previous UTI history (OR = 2.29, 95% CI = 1.15–4.56, P = 0.019) as compared to those who eat cooked meat and had no previous history of UTI.ConclusionsThe prevalence & antimicrobial resistance of uropathogens was high. Health education, continuous surveillance of UTI and their antimicrobial resistance pattern are essential to reduce the consequence of symptomatic and asymptomatic bacteriuria and multi-drug resistant bacteria in pregnant women.