Panel Of Antibiotics Research Articles

Nutrient Limitation Sensitizes Pseudomonas aeruginosa to Vancomycin.

Traditional antibacterial screens rely on growing bacteria in nutrient-replete conditions which are not representative of the natural environment or sites of infection. Instead, screening in more physiologically relevant conditions may reveal novel activity for existing antibiotics. Here, we screened a panel of antibiotics reported to lack activity against the opportunistic Gram-negative bacterium, Pseudomonas aeruginosa, under low-nutrient and low-iron conditions, and discovered that the glycopeptide vancomycin inhibited the growth of P. aeruginosa at low micromolar concentrations through its canonical mechanism of action, disruption of peptidoglycan crosslinking. Spontaneous vancomycin-resistant mutants underwent activating mutations in the sensor kinase of the two-component CpxSR system, which induced cross-resistance to almost all classes of β-lactams, including the siderophore antibiotic cefiderocol. Other mutations that conferred vancomycin resistance mapped to WapR, an α-1,3-rhamnosyltransferase involved in lipopolysaccharide core biosynthesis. A WapR P164T mutant had a modified LPS profile compared to wild type that was accompanied by increased susceptibility to select bacteriophages. We conclude that screening in nutrient-limited conditions can reveal novel activity for existing antibiotics and lead to discovery of new and impactful resistance mechanisms.

EVALUATION OF MICROBIOLOGICAL PATTERN, ANTIMICROBIAL SENSITIVITY AMONG PATIENTS OF CHRONIC OTITIS MEDIA

Objective: The objective of the present study was to determine the causative pathogen and detect their susceptibility to a panel of antibiotics among patients diagnosed with chronic otitis media (COM). Methods: This was a single-center, hospital-based, cross-sectional, observational study involving total of 156 patients diagnosed with COM. Pus swab collected from the patient’s ear was sent for culture and sensitivity. Results: The mean and median age of the patients included in the present study was 19.1 and 20.5 years, respectively. In the present study, 133 (85.3%) participants were diagnosed with mucosal COM, and the remaining 23 (14.7%) participants had a squamosal type of COM. A positive culture/bacterial growth was seen in 139 samples (89.10%). Of the 139 samples that had bacterial growth: 93.5% had a growth of single bacteria and 6.5% of participants showed growth of more than one bacterium. In the present study, Pseudomonas aeruginosa was the single most common bacteria identified on bacterial culture (32.7%), followed by other Pseudomonas species (23.7%) and Staphylococcus aureus (18.58%). Isolated Pseudomonas specimens were most susceptible to Polymyxin B and Colistin. Isolated Staphylococcus specimens were most sensitive to Meropenem and Imipenem. Conclusion: P. aeruginosa was the single most common bacteria identified on bacterial culture among patients diagnosed with COM. About one in ten (10%) isolated pseudomonas and staphylococcus specimens were multi-drug resistant.

MICROBIAL PROFILE AND NUTRITIONAL EVALUATION OF BROILER AND DOMESTIC CHICKEN MEAT FROM SELECTED DISTRICTS OF KHYBER PAKHTUNKHWA, PAKISTAN

Poultry meat is considered a favourite meal in Pakistan. It is one of the essential constituents of the human diet daily because it contains protein, vitamins, minerals, and energy. Poultry meat can cause illnesses like food poisoning and typhoid etc. Our study aims to isolate pathogenic microbes and nutritional analysis of different poultry meat samples. Samples of domestic (30) and broilers chicken’s (30) meat were collected from different areas (Swat, Malakand, Mardan, Charsadda and Peshawar) of the market randomly. Selective and differential media were used for bacterial growth. The staining techniques and biochemical test were used to identify the bacteria as gram-negative or positive. Different biochemical tests, like Oxidase, Catalase and Triple Sugar Iron (TSI), were performed for the bacterial identification. Disc diffusion procedure was performed to test a panel of antibiotics belongs to different classes against Gram-positive and Gram-negative bacteria. The nutritional analysis was performed by AOAC method. Salmonella, Escherichia coli, Staphylococcus aureus, Clostridium perferingens, Listiria monocytogenes, Yersinia enterocolitica and Campylobacter jejoni were seven different types of bacteria identified from meat sample. Aspergillus and Penicillium, fungi were identified from broiler chicken meat. From the result of antibiotic sensitivity, the most potent antibiotics found against bacteria were ciprofloxacin and Cefotaxime (54%) respectively, followed by ceftriaxone and Gentamicin (40%), respectively, followed by ceftazidim and Imepenem (19%) while pepracillin and penicillin antibiotic were mostly showed resistant. The result of Nutritional analysis showed that crude protein, crude fats, crude fibers, crude ash and crude moisture in domestic chicken meat ranged from 84.19 to 90.52%, 0.62% to 2.30%, 0.36% to 0.65%, 3.70% to 93% and 1.9% to 3.77% respectively. Similarly, in Broiler chicken meat, the percentage of crude protein, crude fats, crude fibers, crude ash and crude moisture ranged from 75.35% to 86.10%, 4.12% to 7.46%, 0.52% to 0.95%, 4.20% to 6.25%, and 1.92% to 2.78% respectively. The study concludes that domestic chicken meat contained a higher percentage of crude protein and crude moisture than broiler meat while a lower percentage of crude fats, crude fiber and crude ash than those of commercial broilers.

Does seminal fluid bacterial isolate(s) affect in vitro fertilization — embryo transfer outcome?

BackgroundThe chance of achieving a successful pregnancy through in vitro fertilization and embryo transfer (IVF-ET) is limited despite recent scientific advances in this field due to several factors that are known to affect the outcome. There are studies linking the presence of bacteria in the male genital tract to poor semen parameters and IVF-ET outcomes. Results are, however, contradictory. The finding of confirmed genital tract infection warrants treatment, especially when dealing with infertile couples, but treating asymptomatic bacteriospermia is controversial. This study assessed the prevalence and effects of seminal fluid bacterial isolates on semen quality and rates of fertilization and biochemical and clinical pregnancies in IVF-ET.MethodologyThis is an analytical cross-sectional study conducted at the IVF Center of National Hospital Abuja, Nigeria. Due to the low turnout of clients, we enrolled all consecutive consenting eligible male partners of women undergoing the procedure during the study period to obtain a sample size of 242. Participants observed sterile techniques to prevent contamination of the seminal fluid during collection. Growth of bacteria > 10,000 colony-forming units (CFU)/ml was considered significant and tested for sensitivity to a panel of antibiotics. We determined the influence of positive bacterial isolates on fertilization, biochemical pregnancy, clinical pregnancy (primary outcome), and multiple pregnancies. Data were analyzed using SPSS version 22. Student’s t-test, chi-square test, and Fisher’s exact tests were employed as appropriate. p-value < 0.05 at a 95% confidence interval was regarded as statistically significant.ResultsSeminal fluid culture was positive in 57 patients (47.11%). Staphylococcus aureus was the predominant organism cultured (43.90%), followed by Streptococci spp. (21.05%), Escherichia coli (17.54%), Klebsiella spp. (8.77%), Pseudomonas aeruginosa (5.26%), Staphylococcus saprophyticus (1.75%), mixed Staphylococcus aureus, and Streptococcus spp. organisms (1.75%). The fertilization rate was 95.4%, the biochemical pregnancy rate was 42.2%, the clinical pregnancy rate was 38%, and the multiple pregnancy rate was 16.53%. Significant factors found to be associated with positive clinical pregnancy were primary infertility (p-value = 0.001) and negative seminal fluid culture result (p-value = 0.033).ConclusionThe prevalence of bacteriospermia was relatively high, and the presence of bacterial isolates adversely affected fertilization and clinical pregnancy rates among couples undergoing the IVF-ET program.

Electrical Broth Micro-Dilution for Rapid Antibiotic Resistance Testing.

Rapid tests to assess the susceptibility of bacteria to antibiotics are required to inform antibiotic stewardship. We have developed a novel test, which measures changes in the impedance of a 100 nanoliter volume of bacterial suspension to determine an "electrical" minimum inhibitory concentration (eMIC). Two representative strains of Klebsiella pneumoniae, Acinetobacter baumannii, Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus were tested against a panel of frontline antibiotics with different modes of action (ciprofloxacin, doxycycline, colistin and imipenem, gentamicin, and ceftazidime). The eMIC measured at 1 h correlated strongly with a standard 24 h microbroth dilution MIC for all combinations of antibiotics and bacteria, allowing strains to be correctly assigned as sensitive or resistant measured in a fraction of the time.

Antibiotic Sensitivity Pattern of Carbapenem-Resistant Pseudomonas Aeruginosa

Objective: To determine the sensitivity of Carbapenem-resistant Pseudomonas aeruginosa (CARP) with the panel of antibiotics according to Clinical and Laboratory Standards Institute (CLSI) 2020 guidelines.&#x0D; Study Design: Cross-sectional study.&#x0D; Duration and Place of Study: Armed Forces Institute of Pathology, Rawalpindi from Pakistan, Apr to Sep 2020.&#x0D; Methodology: All samples received at the Microbiology Department during the study period were included. Various samples such as blood, pus, sputum, Endobronchial washing (EBW), non-directed bronchial lavage (NBL), tissue and urine were processed in the laboratory. Samples were inoculated on appropriate culture media, and bacteria were identified according to their colony morphology, Gram staining characteristics and biochemical tests. Antibiotic susceptibility testing was performed using the Kirby Bauer Disk Diffusion technique according to Clinical and Laboratory Standards Institute (CLSI) 2020 guidelines. However, for susceptibility to Colistin, the agar dilution method was performed.&#x0D; Results: In our study, fifty-five Carbapenem-resistant Pseudomonas aeruginosa were isolated. Out of these fifty-five isolates,thirteen (23.6%) were sensitive to Tazocin, seven (12.7%) were sensitive to Ceftazidime, fourteen (25.4%) were sensitive to Gentamicin, 7(12.7%) were sensitive to Cefepime, (12.7%) to Aztreonam, 10(18.2%) were sensitive to Amikacin, 7(12.7%) to Ciprofloxacin, 6(11%) to Levofloxacin and forty-two (76.4%) were sensitive to Colistin.&#x0D; Conclusion: The susceptibility of Carbapenem-resistant Pseudomonas aeruginosa to all the antibiotics tested in this study was low. Isolates displayed the highest susceptibility to Colistin.Keywords: Antibiotic susceptibility profile, Carbapenems, Carbapenem-resistant Pseudomonas aeruginosa (CRPA), Disk diffusion technique.

Synergistic antimicrobial effect of ascorbic acid and nicotinamide with rifampicin and vancomycin against SCCmec type IV methicillin-resistant Staphylococcus aureus (MRSA).

Background. Methicillin-resistant Staphylococcus aureus (MRSA) is a pathogenic bacteria involved in a wide spectrum of human diseases. Many virulence factors promote this widespread propagation. One important factor is acquiring antibiotic resistance genes, which leads to a reduction in the availability and efficacy of therapy options. Recently, research has suggested that the remarkable antimicrobial effect of antioxidants against superbugs such as MRSA shows synergistic effects when accompanied by antimicrobial therapy. This paper aims to examine the synergistic effects of ascorbic acid and nicotinamide with a panel of antibiotics used in antimicrobial therapy against MRSA. Material and Methods. Two SCCmec type IV MRSA reference strains (EMRSA-15 and USA300) and 10 MRSA clinical isolates feature in this paper. SCCmec typing was conducted on the 10 clinical isolates via multiplex PCR after identification. Synergy experiments on antioxidants and antibiotics were evaluated via checkerboard assay. The minimum inhibitory concentration (MIC) of each agent was determined in accordance with the Clinical and Laboratory Standards Institute (CLSI) M100 guidelines through twofold microdilution assay. Results and Discussion. Synergy (FIC <0.5) was demonstrated for ascorbic acid (1/2 to 1/4 MIC) with rifampicin (1/2 to 1/8 MIC), and also ascorbic acid (1/2 to 1/16 MIC) when associated with vancomycin (1/2 MIC). Similarly, nicotinamide (1/2 to 1/16 MIC) showed a synergistic effect when paired with low concentrations of rifampicin (1/2 to 1/16 MIC), and also (at 1/4 to 1/16 MIC) with vancomycin (1/2 MIC). All reduced MICs due to synergistic combinations demonstrated statistical significance (P<0.05). Conclusion. The synergistic activity demonstrated in associating antioxidants with antibiotics shows promise in managing superbugs. However, more research is required to better understand the mechanism of the synergy and for utilization in clinical care.

Delhi's network for surveillance of antimicrobial resistance: The journey, challenges and output from first year

PurposeAntimicrobial resistance [AMR] has emerged as a global and national priority and establishing an effective surveillance system for antimicrobial resistance is an essential prerequisite for generating evidence for informed policymaking at both national and state levels. MethodsTwenty-four laboratories were enrolled after assessment in the WHO-IAMM Network for Surveillance of Antimicrobial Resistance in Delhi [WINSAR-D]. The NARS- NET standard operating procedures were adopted along with its priority pathogen lists and antibiotic panels. The members were trained to use WHONET software and monthly data files were collected, collated, and analyzed. ResultsMultiple logistic issues such as procurement, erratic supply of consumables, non-availability of standard guidelines, lack of automated systems, high workload and low manpower were reported by the majority of member laboratories. Microbiological challenges such as differentiation between colonization and pathogen in absence of patient details, lack of confirmation of resistance, identification of isolates and lack of dedicated computer and genuine windows software for data were common to most laboratories. The total number of isolates of priority pathogens in 2020 was 31,463. Of these, 50.1% isolates were from urine 20.6% were from blood and 28.3% were from pus aspirate and other sterile body fluids. High levels of resistance were observed for all antibiotics. ConclusionThere are many challenges in generating quality AMR data in lower-middle-income countries. There is a need for resource allocation and capacity building at all levels to ensure the collection of quality assured data.

Investigation of a combination therapy approach for the treatment of melioidosis.

The efficacy of finafloxacin as a component of a layered defense treatment regimen was determined in vitro and in vivo against an infection with Burkholderia pseudomallei. Doxycycline was down-selected from a panel of antibiotics evaluated in vitro and used in combination with finafloxacin in a Balb/c mouse model of inhalational melioidosis. When treatment was initiated at 24 h post-infection with B. pseudomallei, there were no differences in the level of protection offered by finafloxacin or doxycycline (as monotherapies) when compared to the combination therapy. There was evidence for improved bacterial control in the groups treated with finafloxacin (as monotherapies or in combination with doxycycline) when compared to mice treated with doxycycline. Survival comparisons of finafloxacin and doxycycline (as monotherapies) or in combination initiated at 36 h post-infection indicated that finafloxacin was superior to doxycycline. Doxycycline was also unable to control the levels of bacteria within tissues to the extent that doxycycline and finafloxacin used in combination or finafloxacin (as a sole therapy) could. In summary, finafloxacin is a promising therapy for use in the event of exposure to B. pseudomallei.

Effect of pneumococcal conjugate vaccines and SARS-CoV-2 on antimicrobial resistance and the emergence of Streptococcus pneumoniae serotypes with reduced susceptibility in Spain, 2004–20: a national surveillance study

BackgroundEpidemiological studies are necessary to explore the effect of current pneumococcal conjugate vaccines (PCVs) against antibiotic resistance, including the rise of non-vaccine serotypes that are resistant to antibiotics. Hence, epidemiological changes in the antimicrobial pattern of Streptococcus pneumoniae before and during the first year of the COVID-19 pandemic were studied.MethodsIn this national surveillance study, we characterised the antimicrobial susceptibility to a panel of antibiotics in 3017 pneumococcal clinical isolates with reduced susceptibility to penicillin during 2004–20 in Spain. This study covered the early and late PCV7 periods; the early, middle, and late PCV13 periods; and the first year of the COVID-19 pandemic, to evaluate the contribution of PCVs and the pandemic to the emergence of non-vaccine serotypes associated with antibiotic resistance.FindingsSerotypes included in PCV7 and PCV13 showed a decline after the introduction of PCVs in Spain. However, an increase in non-PCV13 serotypes (mainly 11A, 24F, and 23B) that were not susceptible to penicillin promptly appeared. A rise in the proportion of pneumococcal strains with reduced susceptibility to β-lactams and erythromycin was observed in 2020, coinciding with the emergence of SARS-CoV-2. Cefditoren was the β-lactam with the lowest minimum inhibitory concentration (MIC)50 or MIC90 values, and had the highest proportion of susceptible strains throughout 2004–20.InterpretationThe increase in non-PCV13 serotypes associated with antibiotic resistance is concerning, especially the increase of penicillin resistance linked to serotypes 11A and 24F. The future use of PCVs with an increasingly broad spectrum (such as PCV20, which includes serotype 11A) could reduce the impact of antibiotic resistance for non-PCV13 serotypes. The use of antibiotics to prevent co-infections in patients with COVID-19 might have affected the increased proportion of pneumococcal-resistant strains. Cefotaxime as a parenteral option, and cefditoren as an oral choice, were the antibiotics with the highest activity against non-PCV20 serotypes.FundingThe Spanish Ministry of Science and Innovation and Meiji-Pharma Spain.TranslationFor the Spanish translation of the abstract see Supplementary Materials section.

Molecular epidemiology and antimicrobial resistance patterns of Clostridioides difficile isolates in Algerian hospitals.

Clostridioides difficile is a major pathogen responsible for hospital-associated diarrhoea. This study investigated the molecular epidemiology and antibiotic resistance of C. difficile isolates in five Algerian hospitals. Between 2016 and 2019, faecal specimens were collected from in-patients and were cultured for C. difficile. Isolates were characterised by toxin genes detection, Polymerase Chain Reaction (PCR)-ribotyping, Multilocus Sequence Typing (MLST), antimicrobial susceptibility testing against a panel of antibiotics, and screened for antimicrobial resistance genes. Out of 300 patient stools tested, 18 (6%) were positive for C. difficile by culture, and were found to belong to 11 different ribotypes (RT) and 12 sequence types (ST): RT 085/ST39, FR 248/ST259, FR 111/ST48, RT 017/ST37, RT 014/ST2, RT 014/ST14, FR 247/new ST, RT 005/ST6, RT 029/ST16, RT 039/ST26, RT 056/ST34 and RT 446/ST58. MLST analysis assigned the isolates to two clades, 1 and 4. Clade 4 was more homogeneous, as it mainly included non-toxigenic isolates. Three toxin gene profiles were detected, two toxigenic, A+B+CDT- (33.3%) and A-B+CDT- (11%); and one non-toxigenic, A-B-CDT- (55.5%). All C. difficile isolates were susceptible to metronidazole, vancomycin and moxifloxacin. Overall prevalence of C. difficile in our healthcare settings was 6%. Antibiotic resistance rates ranged from 72.2% (clindamycin) to 16.6% (tetracycline). This study highlighted a relatively high genetic diversity in term of ribotypes, sequence types, toxin and antibiotic resistance patterns, in the C. difficile isolates. Further larger studies are needed to assess the true extent of C. difficile infections in Algeria.

Nanoparticle-Enabled Combination Therapy Showed Superior Activity against Multi-Drug Resistant Bacterial Pathogens in Comparison to Free Drugs.

The emergence of multidrug-resistant (MDR) bacterial pathogens in farm animals and their zoonotic spread is a concern to both animal agriculture and public health. Apart from antimicrobial resistance (AMR), bacterial pathogens from the genera of Salmonella and Staphylococcus take refuge inside host cells, thereby demanding intervention strategies that can eliminate intracellular MDR pathogens. In this study, seven clinical isolates of Salmonella and Staphylococcus from swine farms were characterized for antibiotic (n = 24) resistance, resistance mechanisms, and virulence characteristics. All isolates showed resistance to one or more antibiotics and S. enterica ser. Typhimurium isolate had the highest resistance to the panel of antibiotics tested. Major resistance mechanisms identified were efflux pump and beta-lactamase enzyme activities. Staphylococcus isolates showed complete hemolysis and strong biofilm formation, while Salmonella isolates caused partial hemolysis, but showed no or weak biofilm formation. MDR isolates of S. aureus M12 and S. enterica ser. Typhimurium bacteria were subsequently tested against combinations of antibiotics and potentiating adjuvants for improved antibacterial efficacy using a checkerboard assay, and their fractional inhibitory concentration index (FICI) was calculated. A combination of chitosan and silica nanoparticles containing tetracycline (TET) and efflux pump inhibitor chlorpromazine (CPZ), respectively, was characterized for physicochemical properties and effectiveness against MDR Salmonella enterica ser. Typhimurium isolate. This combination of nano-encapsulated drugs improved the antibacterial efficacy by inhibiting AMR mechanisms (efflux activity, beta-lactamase enzyme activity, and hydrogen sulfide (H2S) production) and reducing intracellular pathogen load by 83.02 ± 14.35%. In conclusion, this study sheds light on the promising applicability of nanoparticle-enabled combination therapy to combat multidrug-resistant pathogens encountered in animal agriculture.

A crowd of BashTheBug volunteers reproducibly and accurately measure the minimum inhibitory concentrations of 13 antitubercular drugs from photographs of 96-well broth microdilution plates.

Tuberculosis is a respiratory disease that is treatable with antibiotics. An increasing prevalence of resistance means that to ensure a good treatment outcome it is desirable to test the susceptibility of each infection to different antibiotics. Conventionally, this is done by culturing a clinical sample and then exposing aliquots to a panel of antibiotics, each being present at a pre-determined concentration, thereby determining if the sample isresistant or susceptible to each sample. The minimum inhibitory concentration (MIC) of a drug is the lowestconcentration that inhibits growth and is a more useful quantity but requires each sample to be tested at a range ofconcentrations for each drug. Using 96-well broth micro dilution plates with each well containing a lyophilised pre-determined amount of an antibiotic is a convenient and cost-effective way to measure the MICs of several drugs at once for a clinical sample. Although accurate, this is still an expensive and slow process that requires highly-skilled and experienced laboratory scientists. Here we show that, through the BashTheBug project hosted on the Zooniverse citizen science platform, a crowd of volunteers can reproducibly and accurately determine the MICs for 13 drugs and that simply taking the median or mode of 11-17 independent classifications is sufficient. There is therefore a potential role for crowds to support (but not supplant) the role of experts in antibiotic susceptibility testing.

Ralstonia mannitolilytica: an emerging multidrug-resistant opportunistic pathogen in a tertiary care hospital setting.

Introduction. Ralstonia mannitolilytica is a rare opportunistic pathogen capable of causing a serious infection in immunocompromised patients. Our objective was to describe all cases of R. mannitolilytica bloodstream infection identified within 2 years at our tertiary care centre, focusing on clinical characteristics, risk factors, antibiotic sensitivity patterns, management and outcomes.Case Series.We compiled a descriptive case series including 14 non-duplicate R. mannitolilytica isolates obtained from bloodstream infection samples from the microbiology laboratory of a tertiary care centre from June 2019 to June 2021. All isolates were initially identified based on their morphological properties and biochemical reactions, and then underwent matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) examination for confirmation of identity. Antibiotic susceptibility testing was performed using the Kirby–Bauer disc diffusion method and Vitek 2. All 14 patients presented with symptoms of fever and/or chills, and a positive blood culture for R. mannitolilytica . After 48 h of incubation, no Ralstonia growth was reported from any of the current environmental or pharmaceutical water samples. Chemotherapy (9/14), mechanical ventilation (4/14), steroid use (2/14) and diabetes mellitus (1/14) were associated risk factors in our patients. The antibiotic sensitivity panel showed maximum resistance to aminoglycosides (64.3%) and no resistance to cefoperazone/sulbactum. Patients received treatment with cefoperazone/sulbactum and meropenem or ceftazidime. Thirteen patients recovered with antibiotic therapy and one patient succumbed to his illness.Conclusion. R. mannitolilytica can cause bloodstream infections in immunocompromised patients. It is likely to be missed or underreported due to lack of clinical awareness. MALDI-TOF MS is helpful in rapid identification. R. mannitolilytica is resistant to many routinely used antibiotics, including carbapenems.

Bacteriological profile and antibiogram analysis from a tertiary care centre in eastern India: Time to Act / ReAct

Development of antimicrobial resistance imposes a serious threat to the timely and efficient healing of mankind who fall prey to the infectious agents. It is increasingly being reported day by day throughout the world. Irrational and overuse of antibiotics coupled with unavailability of regional or local antibiogram aggravates the situation further.To understand and present the local antbiogram data for this region and bridge the existing knowledge gap about the same for this particular region.Two year data was retrospectively analyzed from a 750 bedded tertiary care centre.A total of 1143 non repeat isolates were studied, their antibiogram profiles were analyzed. Percentage of Gram negative bacteria obtained were 59.6%, while Gram Positive bacteria were obtained in 40.4% of the isolates. (22.8%) was the most common organism isolated, followed by Staphylococcus aureus (14.2%), Other sp(12.8%), sp(12.6%), (9.4%), and complex(7.4%), Miscellaneous Bacteria(13.4%). An alarming number of isolates were found to be Multidrug resistant isolates(MDRs). With the panel of antibiotics tested for Gram negative bacterial isolates, only Fosfomycin(1.5%), Nitrofurantoin(16%) &amp; Chloramphenicol (19%) were the only antibiotics to exhibit &amp;#60;20% resistance. Antibiotics for Gram positive bacteria for which low resistance was observed were Vancomycin (0%), Linezolid (0.1%), Teicoplanin (&amp;#60;1%), Aminoglycosides (18%), Nitrofurantoin(15%), Chloramphenicol(6%) &amp; Tetracyclines(11%). Extended Spectrum Beta lactamase(ESBL) prevalence was estimated to be 63.6% in , 82.4% in Klebsiellapneumoniae. Methicillin resistant Staphylococcus aureus (MRSA) was seen in 54% of the isolates, while Inducible clindamycin resistance was observed in 35.9% of the isolates.It is high time that we shift our focus from internationally and nationally available data on antibiogram to locally prevalent antibiotic resistance pattern. It will ensure faster patient recovery at a lesser cost and also prevent undue development of drug resistance.

Bacterial Glycocalyx Integrity Impacts Tolerance of Myxococcus xanthus to Antibiotics and Oxidative-Stress Agents.

The presence of an exopolysaccharide (EPS) layer surrounding bacterial cells, termed a “glycocalyx”, confers protection against toxic molecules. However, the effect of glycocalyx integrity on the tolerance to such agents is poorly understood. Using a modified disc-diffusion assay, we tested the susceptibility to a panel of antibiotics and oxidative stress-inducing compounds of various mutant strains of the social predatory Gram-negative soil bacterium Myxococcus xanthus; the selected mutants were those that manifest different physical states of their respective EPS glycocalyces. While the overall presence of an EPS layer was indeed beneficial for tolerance, the integrity of this layer was also found to affect the susceptibility of the bacterium to killing; however, this finding was not universal, and instead was dependent on the specific compound tested. Thus, the integrity of the cell-surface EPS glycocalyx plays an important role in the tolerance of M. xanthus to harmful compounds.

Faecal carriage of multi-drug resistant Enterobacteriaceae in hospitalized children at University Teaching Hospital Sylvanus Olympio of Lomé, Togo

Background: High prevalence of infections and associated antibiotherapy may put children at increased risk for development of multidrug-resistance (MDR), mostly to bacterial infections. The objective of this study therefore was to determine the prevalence of gastrointestinal carriage of MDR Enterobacteriaceae among hospitalized children in the Paediatric department of Sylvanus Olympio University Hospital, Lomé, Togo.Methodology: A descriptive cross-sectional study was carried out on randomly selected hospitalized children in the Paediatric wards of the hospital from November 03 to November 10, 2020, after obtaining informed consent from their parents/guardians. Rectal swabs and stool samples were collected from each participant and cultured for isolation of members of the family Enterobacteriaceae on Hektoen enteric agar containing 4 µg/L cefotaxime, which was incubated aerobically at 37oC for 24 hours. The isolates were identified using in-house biochemical tests. Antibiotic susceptibility test (AST) of each isolate to a panel of antibiotics including ertapenem and imipenem was done by the disc diffusion method and interpreted according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST) clinical breakpoints version 2020 V.1.1. ESBL production was detected by the double-disc synergy test of amoxicillin and clavulanic acid, and resistance to carbapenem was inferred by resistance to ertapenem and imipenem discs in the AST. Multi-drug resistance (MDR) was defined as resistance to at least three families of antibiotics. Statistical analysis of data was carried out on Excel 2010 and EPI INFO 7.2 and p value &lt; 0.05 was considered to be statistical significance. Results: A total of 70 hospitalized children during the study period were randomly recruited with an average age of 4 years 3 days and a range of 1 day to 18 years. The male gender was predominant (54.3%) with a M: F ratio of 1.2. Samples were culture positive in 85.7% (60/70) and a total of 72 species of Enterobacteriaceae were isolated in 93.3% (56/60) of these cultures. Escherichia coli was the most frequently isolated species(56.9%, 41/72). More than 90% (65/72) of the isolates were resistant to ampicillin, 58.3% (42/72) to third generation cephalosporins, 59.7% (43/72) to fourth generation cephalosporins, 43% (31/72) to amino-glycosides, 55.6% (40/72) were multi-drug resistant, 48.6% (35/72) were ESBL-producing strains, and 6.9% (5/72) were carbapenem resistant. Eighty-three percent (29/35) of ESBL-producing and all the carbapenem resistant isolates (5/5) were recovered from children on antibiotic therapy. The prevalence of ESBL-producing phenotypes among culture-positive children on antibiotic treatment (72.5%, 29/40) was significantly higher than among culture-positive children not on antibiotic treatment (20.0%, 4/20), indicating that antibiotic therapy was significantly associated with carriage of MDR isolates (OR=10.545, 95% CI=2.882-38.590, p=0.0002). Conclusion: The high faecal carriage rate of MDR Enterobacteriaceae, which are all ESBL-producing strains, in this study is worrying. There is urgent need to develop measures to monitor and limit the spread of these MDR organisms in children and the community in Togo.

A national longitudinal study evaluating the activity of cefditoren and other antibiotics against non-susceptible Streptococcus pneumoniae strains during the period 2004-20 in Spain.

Surveillance studies including antibiotic resistance and evolution of pneumococcal serotypes are critical to evaluate the susceptibility of commonly used antibiotics and the contribution of conjugate vaccines against resistant strains. To determine the susceptibility of clinical isolates of Streptococcus pneumoniae with reduced susceptibility to penicillin to a panel of antibiotics during the period 2004-20 and characterize the impact of pneumococcal conjugate vaccines in the evolution of resistant serotypes. We selected 3017 clinical isolates in order to determine the minimal inhibitory concentration to penicillin, amoxicillin, cefotaxime, erythromycin, levofloxacin and oral cephalosporins, including cefditoren, cefixime and cefpodoxime. The antibiotics with the lowest proportion of resistant strains from 2004 to 2020 were cefditoren (<0.4%), followed by cefotaxime (<5%), penicillin (<6.5%) and levofloxacin (<7%). Among oral cephalosporins, cefixime was the cephalosporin with the highest MIC90 (32 mg/L) and MIC50 (8-16 mg/L) throughout the study, followed by cefpodoxime with highest values of MIC90 (4 mg/L) and MIC50 (2 mg/L) for the majority of the study period. In contrast, cefditoren was the cephalosporin with the lowest MIC90 (1 mg/L) and MIC50 (0.25-0.5 mg/L). Cefditoren was the antibiotic with the highest proportion of susceptible strains. Hence, more than 80% of the clinical strains were susceptible to cefditoren throughout the period 2004-20. The proportion of resistant isolates to cefditoren and cefotaxime was scarce, being less than 0.4% for cefditoren and lower than 5% for cefotaxime, despite the increased rates of serotypes not covered by the 13-valent pneumococcal conjugate vaccine.

Genomic Analysis of Highly Virulent blaCTX-M, blaSHV and blaTEM Genes in Resistant Strains of E.coli and Klebsiella: an emerging threat

Background: The term antimicrobial resistance refers to the ability to resists the effects of drugs formally used to treat them and this term relates only to bacteria becoming resistant. Microorganisms that are resistant to multiple drugs are known as multidrug-resistant bacteria. Aim: To investigate the prevalence of SHV, TEM and CTXm genes from E.coli and Klebsiella isolated from patients of Lahore, Pakistan. Methods: Patients with prolonged hospital stay were enrolled in this cross-sectional study with 60 samples comprising Klebsiella pneumoniae and Escherichia coli (Ctx, Cro, Caz resistant) were identified in clinical specimens. To assess susceptibility, the disc diffusion method was applied with eight antibiotic panel of cephalosporin 3rd generation. A Double disc, combined disc test was used to identify the ESBL-producing bacteria. By real - time PCR, The presence of the genes encoding blaTEM, blaSHV, and blaCTXm was tested in ESBL positive isolates as well as additional isolates with MICs of less than 4g/mL for ceftazidime, cefotaxime, ceftriaxone, and aztreonam (PCR). Results: The frequency of E. coli and Klebsiella bacteria was found in 59% and 41% of the 60 samples, respectively. According to the data, 23 isolates (16.37%) were multidrug resistant, and 7(6.89%) were ESBL-positive. At least one of the antibiotics ceftazidime, ceftriaxone, or cefotaxime was resistant to 30(25.86%) of the isolates. The ESBL genes were sequenced to corroborate the PCR result. Conclusions: Among E. coli and Klebsiella bacteria obtained from patients, blaTEM-116 was the most frequently isolated ESBL gene, followed by Shv and Ctxm. Keywords: Antibiotic Resistance, Beta- Lactamases, E. coli, Klebsiella pneumonia

Combinatorial screening SlipChip for rapid phenotypic antimicrobial susceptibility testing.

Antimicrobial resistance (AMR) by bacteria is a serious global threat, and a rapid, high-throughput, and easy-to-use phenotypic antimicrobial susceptibility testing (AST) method is essential for making timely treatment decisions and controlling the spread of antibiotic resistant micro-organisms. Traditional culture-based methods are time-consuming, and their capability to screen against a large number of different conditions is limited; meanwhile genotypic based methods, including sequencing and PCR based methods, are constrained by rarely identified resistance genes and complicated resistance mechanisms. Here, a combinatorial-screening SlipChip (cs-SlipChip) containing 192 nanoliter-sized compartments is developed which can perform high-throughput phenotypic AST within three hours by monitoring the bacterial growth within nanoliter-sized droplets with bright-field imaging and analyzing the changes in bacterial number and morphology. The minimum inhibitory concentration (MIC) of Escherichia coli ATCC 25922 against four antibiotics (ampicillin, ciprofloxacin, ceftazidime, and nitrofurantoin) can be measured in one chip within 3 hours. Furthermore, five antibiotic-resistant E. coli strains were isolated from patients diagnosed with urinary tract infections (UTIs), and an individual isolate was tested using four antibiotics and eleven antibiotic combinations simultaneously with three different concentrations of each. The results from the cs-SlipChip agree with those of a VITEK 2 automated system. This cs-SlipChip provides a practical high-throughput and rapid phenotypic method for AST and can also be used to screen different chemicals and antibiotic combinations for the treatment of multiple antibiotic-resistant bacteria.