Bacteriological Profile, Antimicrobial Susceptibility Patterns and Predictors of Bacteremia in Neonates with Clinical Sepsis at KCMC Hospital, Northern Tanzania

Background: Despite a significant decline in neonatal deaths in the last 20 years (5 million in 1990 to 2.4 million in 2019), the risk of death is still high, especially in developing countries. In Tanzania, neonatal sepsis is the third leading cause of neonatal death, accounting for 25% of all deaths. The rising global threat of antimicrobial resistance and the rising burden of neonatal death due to neonatal sepsis have been of great concern and have delayed progress toward reaching SDG goal 3.2 by 2030. This study aims to determine the bacteriological profile, antibiotic susceptibility patterns, and predictors of bacteremia among neonates with clinical sepsis at KCMC Hospital in Northern Tanzania. Methodology: This study had a cross-sectional design conducted at KCMC Hospital, Northern Tanzania. The study population was neonates admitted to the neonatal unit at KCMC Hospital. Data were collected using questionnaires and blood cultures from neonates. Frequencies and proportions were used to summarize categorical variables, while continuous variables were summarized using mean and standard deviation. The frequencies and proportions of bacteria isolated and the antimicrobial susceptibility results were analyzed and compared using Pearson’s chi-square test and Fisher’s exact test where applicable. Modified Poisson regression model was used to determine factors associated with positive blood culture. Results: Out of 411 neonates with a clinical diagnosis of neonatal sepsis, 175 (42.9%) had positive blood cultures. Gram-positive bacteria were most frequently isolated at 52.3%, and gram-negative bacteria were 47.7%. Coagulase-negative Staphylococcus (30.7%) and Staphylococcus aureus (19.9%) were the predominant gram-positive isolates. Gram-negative isolates were Klebsiella spp 47 (26.7%), E. coli 10 (5.7%), and Citrobacter spp 10 (5.1%). The gram-positive isolates were sensitive to vancomycin, piperacillin/tazobactam, and ceftazidime, whereas the gram-negative were sensitive to amikacin, meropenem, and vancomycin. The study did not find statistically significant associations between clinical factors and positive blood cultures in bacteremia. Conclusion: Gram-positive bacteria are the dominant pathogens in early-onset and late-onset neonatal sepsis. High levels of resistance to ampicillin and ceftriaxone and moderate resistance to gentamycin were observed in both gram-positive and gram-negative bacteria. Gram-positive organisms exhibit better susceptibility rates to vancomycin and ciprofloxacin, while gram-negative micro-organisms are more sensitive to amikacin and meropenem. An effective initial treatment approach for neonatal sepsis would involve a combination of drugs.

Antimicrobial susceptibility testing for Helicobacter pylori in times of increasing antibiotic resistance

The gram-negative bacterium Helicobacter pylori(H.pylori)causes chronic gastritis,gastric and duodenal ulcers,gastric cancer and mucosa-associated lymphoid tissue lymphoma.Treatment is recommended in all symptomatic patients.The current treatment options for H.pylori infection are outlined in this review in light of the recent challenges in eradication success,largely due to the rapid emergence of antibiotic resistant strains of H.pylori.Antibiotic resistance is a constantly evolving process and numerous studies have shown that the prevalence of H.pylori antibiotic resistance varies significantly from country to country,and even between regions within the same country.In addition,recent data has shown that previous antibiotic use is associated with harbouring antibiotic resistant H.pylori.Local surveillance of antibiotic resistance is warranted to guide clinicians in their choice of therapy.Antimicrobial resistance is assessed by H.pylori culture and antimicrobial susceptibility testing.Recently developed molecular tests offer an attractive alternative to culture and allow for the rapid molecular genetic identification of H.pylori and resistance-associated mutations directly from biopsy samples or bacterial culture material.Accumulating evidence indicates that surveillance of antimicrobial resistance by susceptibility testing is feasible and necessary to inform clinicians in their choice of therapy for management of H.pylori infection.

Importance of antimicrobial susceptibility testing for the management of eradication in Helicobacter pylori infection

The management of Helicobacter pylori(H. pylori) infection treatment differs from the common treatment protocol for other infectious diseases. Because culture-or molecular-guided approaches face several practical issues, such as the invasive procedures required to obtain gastric biopsy specimens and the lack of availability of routine laboratory testing in some places, H. pylori treatment includes the administration of two or three empirically selected antibiotics combined with a proton pump inhibitor rather than evidence-based eradication treatment. The efficacy of empirical therapy is decreasing, mostly due to increasing multiple resistance. Multiresistance to levofloxacin, clarithromycin, and metronidazole, which are commonly used in empirical treatments, appears to have increased in many countries. Mutations play a primary role in the antimicrobial resistance of H. pylori, but many different mechanisms can be involved in the development of antibiotic resistance. Determining and understanding these possible mechanisms might allow the development of new methods for the detection of H. pylori and the determination of antimicrobial resistance. A treatment based on the detection of antimicrobial resistance is usually more effective than empirical treatment. Nevertheless, such an approach before treatment is still not recommended in the Maastricht guidelines due to the difficulty associated with the routine application of available cultureor molecular-based susceptibility tests, which are usually administered in cases of treatment failure. The management of first and rescue treatments requires further research due to the steadily increase in antimicrobial resistance.

Antimicrobial susceptibility testing before first-line treatment for Helicobacter pylori infection in patients with dual or triple antibiotic resistance

To evaluate the efficacy of antimicrobial susceptibility-guided therapy before first-line treatment for infection in patients with dual or triple antibiotic resistance.METHODSA total of 1034 patients infected by Helicobacter pylori (H. pylori) during 2013-2014 were tested for antimicrobial susceptibility. 157 of 1034 (15%) patients showed resistance to two (127/1034; 12%) and to three (30/1034; 3%) antibiotics. Sixty-eight patients with dual H. pylori-resistance (clarithromycin, metronidazole or levofloxacin) were treated for 10 d with triple therapies: OAL (omeprazole 20 mg b.i.d., amoxicillin 1 g b.i.d., and levofloxacin 500 mg b.i.d.) 43 cases, OAM (omeprazole 20 mg b.i.d., amoxicillin 1 g b.i.d., and metronidazole 500 mg b.i.d.) 12 cases and OAC (omeprazole 20 mg b.id., amoxicillin 1 g b.i.d., and clarithromycin 500 mg b.i.d.) 13 cases based on the antimicrobial susceptibility testing. Twelve patients showed triple H. pylori-resistance (clarithromycin, metronidazole and levofloxacin) and received for 10 d triple therapy with OAR (omeprazole 20 mg b.id., amoxicillin 1 g b.i.d., and rifabutin 150 mg b.i.d.). Eradication was confirmed by 13C-urea breath test. Adverse effects and compliance were assessed by a questionnaire.RESULTSIntention-to-treat eradication rates were: OAL (97.6%), OAM (91.6%), OAC (92.3%) and OAR (58.3%). Cure rate was significantly higher in naïve patients treated with OAR-10 compared to patients who had two or three previous treatment failures (83% vs 33%). Adverse events rates for OAL, OAM, OAC and OAR were 22%, 25%, 23% and 17%, respectively, all of them mild-moderate.CONCLUSIONAntimicrobial susceptibility-guided triple therapies during 10 d for first-line treatment leads to an eradication rate superior to 90% in patients with dual antibiotic H. pylori resistance.

Analysis on Antimicrobial Resistance of Clinical Bacteria Isolated from County Hospitals and a Teaching Hospital

The distinction of antimicrobial resistance of clinical bacteria isolated from county hospitals and a teaching hospital was investigated. Disc diffusion test was used to study the antimicrobial resistance of isolates collected from county hospitals and a teaching hospital. The data was analyzed by WHONET5 and SPSS statistic software. A total of 655 strains and 1682 strains were collected from county hospitals and a teaching hospital, respectively, in the year of 2003. The top ten pathogens were Coagulase negative staphylococci （CNS）, E. coil, Klebsiella spp. , S. areus, P. aeruginosa, Enterococcus spp. , Enterobacter spp. , otherwise Salmonella spp. , Proteus spp. , Shigella spp. in county hospitals and Streptococcus spp. , Acinetobacter spp. , X. maltophilia in the teaching hospital. The prevalence of multi-drug resistant bacteria was 5 % （4/86） of methicillin-resistant S. areus （MRSA）, 12 % （16/133） and 15.8 % （9/57） of extended-spectrum β-lactamases producing strains of E. coil and Klebsiella spp. , respectively, in county hospitals. All of the three rates were lower than that in the teaching hospital and the difference was statistically significant （P〈0. 01）. However, the incidence of methicillin-resistant CNS （MRCNS） reached to 70 % （109/156） in the two classes of hospitals. Generally, the antimicrobial resistant rates in the county hospitals were lower than those in the teaching hospital, except the resistant rates of ciprofloxacin, erythromycin, clindamycin, SMZco which were similar in the two classes of hospitals. There were differences between county hospitals and the teaching hospital in the distribution of clinical isolates and prevalence of antimicrobial resistance. It was the basis of rational use of antimicrobial agents to monitor antimicrobial resistance by each hospital.

External Bacterial Flora and Antimicrobial Susceptibility Patterns of Staphylococcus spp. and Pseudomonas spp. Isolated from Two Household Cockroaches, Blattella germanica and Blatta orientalis

A study was performed to estimate the prevalence of the external bacterial flora of two domestic cockroaches （Blattella germanica and Blatta orientalis） collected from households in Tebessa （northeast AIgeria）.Three major bacterial groups were cultured （total aerobic, enterobacteria, and staphylococci） from 14 specimens of cockroaches, and antibiotic susceptibility was tested for both Staphylococcus and Pseudomonas isolates. Culturing showed that the total bacterial load of cockroaches from different households were comparable （P〈0.001） and enterobacteria were the predominant colonizers of the insect surface, with a bacterial load of （2.1×10^5 CFU/insect）, whereas the staphylococci group was the minority. Twenty-eight bacterial species were isolated, and susceptibility patterns showed that most of the staphylococci isolates were highly susceptible to chloramphenicol, gentamycin, pristinamycin, ofloxacin, clindamycin, and vancomycin; however, Pseudomonas strains exhibited resistance to amoxicillin/clavulanic acid, imipenem, and the second-generation antibiotic cephalosporin cefuroxime.

Genetic Characteristics and Antimicrobial Susceptibility of Arcobacter butzleri Isolates from Raw Chicken Meat and Patients with Diarrhea in China

Arcobacter is an emerging foodborne pathogen worldwide.In this study,the prevalence,antimicrobial susceptibility and genetic characteristics of Arcobacter from different sources were investigated.Eighteen A.butzleri isolates were obtained from 60 raw chicken meat samples(16/60,27%)and 150 patients with diarrhea(2/150,1.3%).The resistance ratios to nalidixic acid,ciprofloxacin,clindamycin,chloramphenicol,and florfenicol were 83.33%(15/18),38.89%(7/18),38.89%(7/18),33.33%(6/18)and 33.33%(6/18),respectively.We performed whole genome sequencing of the 18 isolates,and we predicted antibiotic resistance genes and virulence factors by using assembled genomes through blastx analysis.Two resistance genes,blaOXA-464 and tet(H),and the C254T mutation in gyrA,were identified in the genomes of some resistant isolates.Furthermore,virulence genes,such as flgG,flhA,flhB,fliI,fliP,motA,cadF,cjl349,ciaB,mviN,pldA and tlyA,were found in all strains,whereas hecA,hecB and iroE were found in only some strains.Phylogenetic tree analysis of A.butzleri isolates on the basis of the core-genome single nucleotide polymorphisms showed that two isolates from patients with diarrhea clustered together,separately from the isolates from raw chicken and the chicken strains.This study is the first comprehensive analysis of Arcobacter isolated in Beijing.

Prevalence and antimicrobial susceptibility patterns of bacteria in ICU patients with lower respiratory tract infection: A cross-sectional study

Objective: To investigate the prevalence of isolated organisms in patients with lower respiratory tract infections and the antibiotic susceptibilities at a tertiary care center. Methods: In this observational and cross-sectional analysis, 114 patients admitted in the intensive care unit were enrolled. The endotracheal aspirates and bronchoalveolar lavage were collected. The bacteria were isolated and identified, and finally, antimicrobial sensitive pattern of the isolated bacteria was examined. Results: The prevalence of infection was 72.72% in male patients and 27.28% in females. The predominant bacteria were Klebsiella pneumoniae (37.50%) followed by Acinetobacter spp. (36.36%), Pseudomonas aeruginosa (7.95%),Escherichia coli (6.81%), Proteus mirabilis (2.27%), atypical Escherichia coli (1.13%), Enterococcus spp. (1.13%),Elizabethkingia meningoseptica (1.13%),Staphylococcus aureus (1.13%),Proteus vulgaris (1.13%), Citrobacter freundii (1.13%), and Citrobacter koseri (1.13%). High resistance to cephalosporins (82.18%) was demonstrated in all Gram-negative bacteria. Bacteria showed susceptibility to colistin (88.75%) followed by tigecycline (83.11%), gentamycin (36.18%), and amikacin (49.23%). Conclusions: As the most frequent respiratory organisms, Klebsiella pneumoniae and Acinetobacter spp. have increased resistance to cephalosporins and susceptibility to colistin followed by tigecycline.

Streptococcus agalactiae:Identification methods,antimicrobial susceptibility, and resistance genes in pregnant women

BACKGROUND Group B Streptococcus(GBS)is a normal component of the gastrointestinal and genital microbiota in humans and can lead to important infections in newborns.AIM To compare GBS isolation and identification methods as well as to assess the antibiotic susceptibility and to identify resistance genes in GBS strains from pregnant women attended in healthcare services from the city of Vitória da Conquista,in Bahia State,Brazil.METHODS From January 2017 to February 2018,vaginorectal swabs were obtained from 186 participants and the samples were seeded onto chromogenic agar for GBS before and after inoculation in selective broth.Confirmatory identification using 3 CAMP and latex tests was performed in samples with GBS-suggestive colonies.Then,disk diffusion antibiograms were performed in GBS-positive samples,and the detection of the resistance genes ermB,ermTR,mefA,and linB in the clindamycin and/or erythromycin-resistant samples was carried out.RESULTS Thirty-two samples(17.2%)were GBS-positive.The culture in chromogenic agar after sample incubation in selective broth was the most sensitive method(96.9%)for GBS detection.All isolates were susceptible to penicillin,ampicillin,cefotaxime,and vancomycin.Clindamycin resistance was observed in 6 samples(18.8%),while 8 samples(25%)were erythromycin-resistant.All erythromycin and/or clindamycin-resistant GBS strains had negative D-tests.Two strains(25%)presented an M phenotype and 6 isolates(75%)presented a cMLSB phenotype.The ermB gene was identified in 4 samples(44.4%),the mefA gene was also found in 4 samples(44.4%),the ermTR gene was identified in 1 isolate(11.1%),and the linB gene was not found in any isolate.CONCLUSION This study evidenced that the screening for SGB can be performed by means of various methods,including chromogenic media,and that the chemoprophylaxis for pregnant women who cannot use penicillin must be susceptibility-guided.

Expert Consensus on Polymyxin Antimicrobial Susceptibility Testing and Clinical Interpretation

The polymyxins are important antimicrobial agents against antibiotic-resistant gram-negative bacilli.In 2020,the Clinical and Laboratory Standards Institute modified the clinical breakpoints for polymyxin susceptibility test by eliminating the"susceptible"interpretive category,only reporting intermediate(≤2 mg/L)and resistant(≥4 mg/L).However,the European Committee on Antimicrobial Susceptibility Testing recommended the use of clinical breakpoints of W2 mg/L as susceptible and>2 mg/L as resistant.The first-line laboratorians and clinicians in China have been perplexed by the inconsistence of international polymyxin clinical breakpoints and discouraged by the difficulty of conducting polymyxin susceptibility testing.Therefore,it is urgently needed to make it clear for the laboratorians in China to know how to accurately carry out polymyxin susceptibility testing and standardize the interpretation of susceptibility testing results.To this end,the experts from relevant fields were convened to formulate this consensus statement on the testing and clinical interpretation of polymyxin susceptibility.Relevant recommendations are proposed accordingly for laboratorians and clinicians to streamline their daily work.

Studies on Enterotoxins and Antimicrobial Resistance in Staphylococcus aureus Isolated from Various Sources

Staphylococcus aureus represents a public health challenge all over the world. Therefore, this study aims to analyze the prevalence of five genes (sea, seb, sec, see and seg) encoding the staphylococcal enterotoxins in S. aureus isolated from different sources and to evaluate the association of these toxins in comparison to susceptibility towards 12 antimicrobials;antimicrobial susceptibility was conducted by disc diffusion method. Detection of staphylococcal enterotoxins was performed by PCR and the ability to express these genes was assessed among isolates by RT-PCR. The most common enterotoxin gene was sea gene (66%), followed by seb, sec, see and seg (38%, 23%, 19% and 5%) respectively. Expression of sea, seb and seg genes was variable. However, sec and see genes were not expressed by any of the tested isolates. No statistically significant association exists between (seb, sec and see) and isolation sources, while the sea was significantly associated with clinical isolates. High significant correlation was found between elevated sea expression and multidrug-resistance. Our findings indicate that the pathogenic potential of S. aureus may be greater than previously thought. This emphasizes the utmost need to implement proactive measures and more emphasis will be placed on the application of hygiene practices in hospitals to control S. aureus infection and enterotoxins production.

Antimicrobial Susceptibility Patterns of Staphylococcus aureus Strains Isolated at the Namibia Institute of Pathology from 2012 to 2014

Staphylococcus aureus (S. aureus) is known to acquire resistance to new drugs and continues to defy at-tempts to control it. Infections caused by antibiotic resistant strains of S. aureus have reached epidemic proportions globally and the increasing rates of antimicrobial resistance are resulting in fewer treatment options. Methicillin resistant S. aureus (MRSA) has also emerged as a serious therapeutic problem worldwide. However, data on the antimicrobial susceptibility patterns of this bacterium over a period of time in Namibia are not available. A descriptive retrospective study was therefore conducted to investigate the antimicrobial susceptibility patterns of 600 Staphylococcus aureus strains isolated at the Namibia Institute of Pathology (NIP) from January 2012 to December 2014. The results showed that a high proportion of isolates were resistant to penicillin (92.4%) and cotrimoxazole (44.9%), while the antibiotics to which the isolates were least resistant included vancomycin (0%), fusidic acid (0.3%) and ciprofloxacin (4.4%). Methicillin resistance was observed in 13.5% of the staphylococcal isolates. Apart from clindamycin (P value = 0.039) and cotrimoxazole (P value = 0.030), the susceptibility patterns of the antibiotics did not differ significantly over the three years. Moreover, wound swabs and sputum were the clinical samples from which S. aureus was most commonly isolated at NIP. The results from this study suggest that continuous local surveillance on the resistance patterns of S. aureus should be performed on regular basis in Namibia, in order to have adequate information for the empirical treatment of S. aureus infections.

Genomic characterization and antimicrobial susceptibility of bovine intrauterine Escherichia coli and its relationship with postpartum uterine infections

To investigate the roles of Escherichia coli in the pathogenesis of postpartum uterine diseases in dairy cows, a total of 145 E. coli isolates were recovered from 18 healthy cows （61 isolates） and 25 cows with clinical endometritis （84 isolates） at 25-35 days after parturition. Genomic characteristics including phylogenetic grouping, genetic diversity and virulence genes of E. coli isolates were screened to profile the characteristics related to uterine infections. The susceptibility of the bacteria against 23 antibiotics was also evaluated to support prevention and treatment of clinical cases. Genetic diversity of E. coli identified by random amplification of polymorphic DNA （RAPD） revealed 103 clonal types, including 3 common types to unaffected cows and endometritis cows, 39 types specific to healthy cows and 61 types in endometritis subjects. In addition, the isolates from endometritis uteri showed more genetic variability compared with that of healthy cows. Ac- cording to the findings of phylogenetic grouping, the E. coil isolates were assigned to group A （35.9%）, B1 （59.3%） and D （4.8%）. The expression of 10 of 20 virulence gens were detected positively, and only fimH gene was revealed significantly （P〈0.05） associated with endometritis. From antimicrobial susceptibility test, E. coli was found highly resistant to tetracy- cline, ampicillin, carbenicillin and amoxicillin, but sensitive to amikacin, netilmicin, tobramycin, cefepime and ceftazidime. In conclusion, E. cofiwere extensively observed in both healthy and endometritis cows, and presented a large clonal types, however, fimH was the only gene observed associated with clinical endometritis. Our results suggest that the drugs like amikacin, netilmicin, tobramycin and cefepime could be considered for preventing and treating clinical endometritis in the practical management of dairy cow.

Antimicrobial Susceptibility of Streptococcus sp. to Quinupristin-dalfopristin in China

This study aimed to determine the in vitro activity of quinupristin-alfopristin against Streptococcus sp. isolated in China. This agent is not yet available for clinical use, but it has been tested against a high proportion of resistant Staphylococcus oureus strains. A total of 156 streptococcal isolates, which were recovered from various geographic areas and diseases, were tested using the Etest （AB Biodisk, Solna, Sweden）. Quinupristin-alfopristin showed excellent activity against all of the tested streptococci isolates. These results provide useful data for the clinical use of quinupristin-alfopristin in China.

Enumeration,Genetic Characterization and Antimicrobial Susceptibility of Lactobacillus and Streptococcus Isolates from Retail Yoghurt in Beijing,China

Lactic acid bacteria （LAB） are widely used in food industries. Correct identification and safety evaluation of these bacteria at the species even strain level should take considerations into account. In this study, the LAB were recovered from yoghurt and characterized phenotypically and genetically. Fifty-two isolates of LAB from 31 yoghurt samples were cultured and grouped into 6 species including Luctobucillus bulguricus （24 isolates）, Streptococcus thermophilus （15 isolates）, L. ucidophilus （7 isolates）, L. porucusei/cusei （3 isolates）, L. delbrueckii （2 isolates）, and L. fermentum （1 isolate）, based on their Gram-staining, colony morphology and biochemical properties.

Urinary Tract Infection among Adults Seeking Medicare at Kiambu Level 5 Hospital, Kenya: Prevalence, Diversity, Antimicrobial Susceptibility Profiles and Possible Risk Factors

Urinary tract infections are among the most prevalent extra-intestinal infections, with high prevalence globally. This cross-sectional study established prevalence of bacterial aetiology causing urinary tract infection (UTI) and their antimicrobial susceptibility profiles. A questionnaire was used to capture socio-demographic data and possible UTI risk factors among the 206 consented adults seeking medicare at Kiambu Level 5 Hospital. The collected midstream urine samples were subjected to dipstick analysis, microscopy and culture for UTI diagnosis. Results: The overall prevalence rate of UTIs was 27.6%, with women’s prevalence rate being significantly higher at 80.7% compared to men 19.2%. Pregnant women had UTI prevalence at 34% which was higher than other sets of participants. Women who did not frequently change their underpants daily had a higher UTI cases at 34.8%. Escherichia coli, Staphylococcus aureus and Klebsiella pneumoniae were the most prevalent bacterial pathogens at 38.5%, 21% and 19.3%, respectively. Antimicrobial sensitivity analysis revealed high resistances towards Sulfamethoxazole and Ampicillin at range between 50% - 85%, suggesting that these drugs are no longer effective for UTI empirical treatment. The resistance patterns towards Cefotaxime, Cefepime and Ciprofloxacin were below 40%. However, more resistance patterns at a range between 14% - 40% revealed towards Amoxicillin-clavulanic and Nitrofurantoin imply that these are drugs remain potent but there is the need to revise the current UTI management guidelines. In addition, to elude treatment failure, innovation of prophylactic measures is key to halt UTI contraction and offer support to pharmaceutical industries that have fewer new antibiotics in the pipeline.

Comparative antimicrobial activity of Moricin(naturally produced by silk worm,Bombyx mori larvae)against clinically important pathogens

With the emergence and spread of antimicrobial resistance(AMR)it becomes pertinent to search for an antimicrobial alternative to cater for the imminent need to control total drug-resistant(TDR)and multiple-drug-resistant(MDR)infections.Antimicrobial peptides(AMPs)have shown some promise and this study was designed to evaluate antimicrobial activity of Moricin(a naturally produced AMP by silkworm,Bombyx mori larvae)against 276 microbial strains of 83 species.Only two(Erwinia amylovora 1,Hafnia alvei 1)strains were classified as susceptible to Moricin at a concentration≤8μg/mL.If susceptibility criteria were set at MIC equivalent to≤128μg/mL then Moricin inhibited 17 strains.All of the Bacillus species strains and majority of the strains of Acinetobacter,Aeromonas,Enterococcus,Erwinia,Raoultella,and Serratia species were significantly(p<0.05)more often resistant(MIC>512μg/mL)to Moricin than strains belonging to Alacligenes,Bacillus,Escherichia,Klebsiella,Pantoea,Pasteurella,Salmonella,Staphylococcus and Streptococcus species.Susceptibility of different bacteria not only varied significantly to Moricin but also to most of the commonly used antibiotics.The susceptibility of microbes not only affected by their type but also by their source of origin.The study concluded that Moricin has a wide spectrum but limited potential to inhibit clinically important microbial strains belonging to different species and genera.

Genotypic Characterization of Methicillin-resistant Staphylococcus aureus Isolated from Pigs and Retail Foods in China

Objective To investigate the genotypic diversity of Methicillin-resistant Staphylococcus aureus （MRSA） isolated from pigs and retail foods from different geographical areas in China and further to study the routes and rates of transmission of this pathogen from animals to food. Methods Seventy-one MRSA isolates were obtained from pigs and retail foods and then characterized by multi-locus sequencing typing （MLST）, spa typing, multiple-locus variable number of tandem repeat analysis （MLVA）, pulsed-field gel electrophoresis （PFGE）, and antimicrobial susceptibility testing. Results All isolated MRSA exhibited multi-drug resistance （MDR）. Greater diversity was found in food-associated MRSA （7 STs, 8 spa types, and 10 MLVA patterns） compared to pig-associated MRSA （3 STs, 1 spa type, and 6 MLVA patterns）. PFGE patterns were more diverse for pig-associated MRSA than those of food-associated isolates （40 vs. 11 pulse types）. Among the pig-associated isolates, CC9-ST9-t899-MC2236 was the most prevalent clone （96.4%）, and CC9-ST9-t437-MC621 （20.0%） was the predominant clone among the food-associated isolates. The CC9-ST9 isolates showed significantly higher antimicrobial resistance than other clones. Interestingly, CC398-ST398-t034 clone was identified from both pig- and food-associated isolates. Of note, some community- and hospital-associated MRSA strains （t030, t172, t1244, and t4549） were also identified as food-associated isolates. Conclusion CC9-ST9-t899-MC2236-MDR was the most predominant clone in pigs, but significant genetic diversity was observed in food-associated MRSA. Our results demonstrate the great need for improved surveillance of MRSA in livestock and food and effective prevention strategies to limit MDR-MRSA infections in China.

Causative Microorganisms Isolated from Patients with Intra-Abdominal Infections and Their Drug Resistance Profiles:An 11-Year(2011–2021)Single-Center Retrospective Study

Objective To investigate the distribution and antimicrobial susceptibility of causative microorganisms recovered from patients with intra-abdominal infections(IAIs).Methods A total of 2,926 bacterial and fungal strains were identified in samples collected from 1,679 patients with IAIs at the Peking Union Medical College Hospital between 2011 and 2021.Pathogenic bacteria and fungi were identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.Antimicrobial susceptibility testing(AST)was performed using the VITEK 2 compact system and the Kirby–Bauer method.AST results were interpreted based on the M100-Ed31 clinical breakpoints of the Clinical and Laboratory Standards Institute.Results Of the 2,926 strains identified,49.2%,40.8%,and 9.5%were gram-negative bacteria,gram-positive bacteria,and fungi,respectively.Escherichia coli was the most prevalent pathogen in intensive care unit(ICU)and non-ICU patients;however,a significant decrease was observed in the isolation of E.coli between 2011 and 2021.Specifically,significant decreases were observed between 2011 and 2021 in the levels of extended-spectrumβ-lactamase(ESBL)-producing E.coli(from 76.9%to 14.3%)and Klebsiella pneumoniae(from 45.8%to 4.8%).Polymicrobial infections,particularly those involving co-infection with gram-positive and gram-negative bacteria,were commonly observed in IAI patients.Moreover,Candida albicans was more commonly isolated from hospital-associated IAI samples,while Staphylococcus epidermidis had a higher ratio in community-associated IAIs.Additionally,AST results revealed that most antimicrobial agents performed better in non-ESBL-producers than in ESBL-producers,while the overall resistance rates(56.9%–76.8%)of Acinetobacter baumanmii were higher against all antimicrobial agents than those of other common gram-negative bacteria.Indeed,Enterococcus faecium,Enterococcus faecalis,S.epidermidis,and S.aureus were consistently found to be susceptible to vancomycin,teicoplanin,and linezolid.Similarly,C.albicans exhibited high susceptibility to all the tested antifungal drugs.Conclusion The distribution and antimicrobial susceptibility of the causative microorganisms from patients with IAls were altered between 2011 and 2021.This finding is valuable for the implementation of evidence-based antimicrobial therapy and provides guidance for the control of hospital infections.

Intraprocedural gastric juice analysis as compared to rapid urease test for real-time detection of Helicobacter pylori

BACKGROUND Endofaster is an innovative technology that can be combined with upper gastrointestinal endoscopy(UGE)to perform gastric juice analysis and real-time detection of Helicobacter pylori(H.pylori).AIM To assess the diagnostic performance of this technology and its impact on the management of H.pylori in the real-life clinical setting.METHODS Patients undergoing routine UGE were prospectively recruited.Biopsies were taken to assess gastric histology according to the updated Sydney system and for rapid urease test(RUT).Gastric juice sampling and analysis was performed using the Endofaster,and the diagnosis of H.pylori was based on real-time ammonium measurements.Histological detection of H.pylori served as the diagnostic gold standard for comparing Endofaster-based H.pylori diagnosis with RUT-based H.pylori detection.RESULTS A total of 198 patients were prospectively enrolled in an H.pylori diagnostic study by Endofasterbased gastric juice analysis(EGJA)during the UGE.Biopsies for RUT and histological assessment were performed on 161 patients(82 men and 79 women,mean age 54.8±19.2 years).H.pylori infection was detected by histology in 47(29.2%)patients.Overall,the sensitivity,specificity,accuracy,positive predictive value,and negative predictive value(NPV)for H.pylori diagnosis by EGJA were 91.5%,93.0%,92.6%,84.3%,and 96.4%,respectively.In patients on treatment with proton pump inhibitors,diagnostic sensitivity was reduced by 27.3%,while specificity and NPV were unaffected.EGJA and RUT were comparable in diagnostic performance and highly concordant in H.pylori detection(κ-value=0.85).CONCLUSION Endofaster allows for rapid and highly accurate detection of H.pylori during gastroscopy.This may guide taking additional biopsies for antibiotic susceptibility testing during the same procedure and then selecting an individually tailored eradication regimen.