Antibiotic Testing Research Articles

Characterization of Beta-Lactam Resistome of Escherichia coli Causing Nosocomial Infections.

Nosocomial infections caused by Escherichia coli pose significant therapeutic challenges due to the high expression of genes encoding antimicrobial drug resistance. In this study, we investigated the conformation of the beta-lactam resistome responsible for the specific pattern of resistance against beta-lactam antibiotics. A total of 218 Escherichia coli strains were isolated from in-hospital patients diagnosed with nosocomial infections, obtained from various sources such as urine (n = 49, 22.48%), vaginal discharge (n = 46, 21.10%), catheter tips (n = 14, 6.42%), blood (n = 13, 5.96%), feces (n = 12, 5.50%), sputum (n = 11, 5.05%), biopsies (n = 8, 3.67%), cerebrospinal fluid (n = 2, 0.92%) and other unspecified discharges (n = 63, 28.90%). To characterize the beta-lactam resistome, all strains were subjected to antibiotic dilution tests and grown in beta-lactam antibiotics supplemented with Luria culture medium. Subsequently, multiplex PCR and next-generation sequencing were conducted. The results show a multi-drug-resistance phenotype, particularly against beta-lactam drugs. The primary determinant of this resistance was the expression of the blaTEM gene family, with 209 positive strains (95.87%) expressing it as a single gene (n = 47, 21.6%) or in combination with other genes. Common combinations included blaTEM + blaCTX (n = 42, 19.3%), blaTEM + blaCTX + blaSHV (n = 13, 6%) and blaTEM + blaCTX + blaBIL (n = 12, 5.5%), among others. The beta-lactam resistome of nosocomial Escherichia coli strains isolated from inpatients at the "October first" Regional Hospital of ISSSTE was predominantly composed of members of the blaTEM gene family, expressed in various configurations along with different members of other beta-lactamase gene families.

Prevalence and Antimicrobial Resistance Profile of Diarrheagenic Escherichia coli from Fomites in Rural Households in South Africa.

Diarrheagenic Escherichia coli (DEC) pathotypes are the leading cause of mortality and morbidity in South Asia and sub-Saharan Africa. Daily interaction between people contributes to the spreading of Escherichia coli (E. coli), and fomites are a common source of community-acquired bacterial infections. The spread of bacterial infectious diseases from inanimate objects to the surrounding environment and humans is a serious problem for public health, safety, and development. This study aimed to determine the prevalence and antibiotic resistance of diarrheagenic E. coli found in toilets and kitchen cloths in the Vhembe district, South Africa. One hundred and five samples were cultured to isolate E. coli: thirty-five samples were kitchen cloths and seventy-five samples were toilet swabs. Biochemical tests, API20E, and the VITEK®-2 automated system were used to identify E. coli. Pathotypes of E. coli were characterised using Multiplex Polymerase Chain Reaction (mPCR). Nine amplified gene fragments were sequenced using partial sequencing. A total of eight antibiotics were used for the antibiotic susceptibility testing of E. coli isolates using the Kirby-Bauer disc diffusion method. Among the collected samples, 47% were positive for E. coli. DEC prevalence was high (81%), with ETEC (51%) harboring lt and st genes being the most dominant pathotype found on both kitchen cloths and toilet surfaces. Diarrheagenic E. coli pathotypes were more prevalent in the kitchen cloths (79.6%) compared with the toilet surfaces. Notably, hybrid pathotypes were detected in 44.2% of the isolates, showcasing the co-existence of multiple pathotypes within a single E. coli strain. The antibiotic resistance testing of E. coli isolates from kitchen cloths and toilets showed high resistance to ampicillin (100%) and amoxicillin (100%). Only E. coli isolates with hybrid pathotypes were found to be resistant to more than three antibiotics. This study emphasizes the significance of fomites as potential sources of bacterial contamination in rural settings. The results highlight the importance of implementing proactive measures to improve hygiene practices and antibiotic stewardship in these communities. These measures are essential for reducing the impact of DEC infections and antibiotic resistance, ultimately safeguarding public health.

Antibiogram of Staphylococcal Isolates and Molecular Characterisation of Coagulase Negative Staphylococci Obtained from a Hospital in Port Harcourt, Nigeria

Difficulty in the treatment and eradication of bacterial infections as a result of the development of resistance to antibiotics has in recent time remained a serious problem confronting public health. This study investigated the antibiogram of Staphylococcal isolates and molecular characterisation of Coagulase Negative Staphylococci (CoNS) obtained from female patients visiting Rivers State University Teaching Hospital (RSUTH) in Port Harcourt, Nigeria. A total of 103 clinical samples were collected and processed using the standard laboratory procedures. Antibiotic susceptibility test of the isolates was performed using Kirby-Bauer disc diffusion method, following Clinical and Laboratory Standards Institute (CLSI) guidelines. Molecular characterisation as well as screening for the detection of antibiotics resistance MecA gene was carried out using Polymerase Chain Reaction (PCR) dependent molecular techniques. From the study, 22.3% S. aureus and 1.9% CoNS were recovered. The 16SrRNA gene sequencing revealed two species of CoNS namely S. saprophyticus and S. arlettae. The antibiotics susceptibility test results revealed that all the Staphylococcus aureus isolates were 100% resistant to six of the antibiotics tested: Ampicillin, Augmentin, Ceftazidime, Cefuroxime and Cephalexin (β- lactams), 78.3% resistant to Tetracycline and Cotrimoxazole, 73.9% to Vancomycin, 65.2% to Ciprofloxacin, 56.5% to Gentamicin and 47.8% to Erythromycin but 52.2% sensitive to Erythromycin, followed by Gentamicin (34.8%), Ciprofloxacin (17.4%), Vancomycin and Cotrimoxazole (13%) and Tetracycline (8.7%). All (100%) of the Coagulase negative Staphylococci species were resistant to every antibiotics tested. Data obtained from the study showed all the isolates displayed multidrug resistance, with MAR indices greater than 0.2 and Methicillin (MecA) gene was detected in 66.6% of the isolates. The study has reported the presence of Coagulase Negative Staphylococci showing resistance to all the tested antibiotics, hence indicating alarming public health threats. Strict regulation of antimicrobial usage is therefore vital.

Resistance of Klebsiella Sp. Isolated From Chicken and Cages to Chloramphenicol

Klebsiella bacteria is one of the normal flora in poultry that has developed antibiotic resistance. This is reinforced by reports of the incidence of resistance by Klebsiella bacteria in various countries which is quite high. This study aimed to identify the presence of Klebsiella sp. bacteria in chickens and cages, as well as their resistance status to chloramphenicol in relation to the Minister of Agriculture Regulation No. 14/2017. The series of identification included culture, macroscopic and microscopic observations, biochemical tests, and fermentation tests. Antibiotic resistance tests using chloramphenicol disks referring to the Kirby Bauer method. The identification results showed 6 positive samples from 60 samples taken from chickens and 2 positive samples from 21 samples taken from cages. Resistance testing of 8 Klebsiella sp. isolates showed 6 sensitive, 1 intermediate and 1 resistant isolates to chloramphenicol. This is an indication that the Minister of Agriculture Regulation No. 14/2017 is quite effective in prohibiting the use of chloramphenicol in chicken farms.

Standardizing In Vitro β-Lactam Antibiotic Allergy Testing with Synthetic IgE.

The global prevalence of β-lactam allergy poses a major challenge in administering first-line antibiotics, such as penicillins, to a significant portion of the population. The lack of β-lactam IgE antibody pools with defined selectivity hampers the standardization and validation of in vitro assays for β-lactam allergy testing. To address this limitation, this study introduces a synthetic IgE specific to β-lactam antibiotics as a valuable tool for drug allergy research and diagnostic tests. Using phage display technology, we constructed a library of human single-chain antibody fragments (scFv) to target the primary determinant of amoxicillin, a widely used β-lactam antibiotic. Subsequently, we produced a complete human synthetic IgE molecule using the highly efficient baculovirus expression vector system. This synthetic IgE molecule served as a standard in an in vitro chemiluminescence immunoassay for β-lactam antibiotic allergy testing. Our results demonstrated a detection limit of 0.05 IU/mL (0.63 pM), excellent specificity (100%), and a four-fold higher clinical sensitivity (73%) compared to the in vitro reference assay when testing a cohort of 150 serum samples. These findings have significant implications for reliable interlaboratory comparison studies, accurate labeling of allergic patients, and combating the global public health threat of antimicrobial resistance. Furthermore, by serving as a valuable trueness control material, the synthetic IgE facilitates the standardization of diagnostic tests for β-lactam allergy and demonstrates the potential of utilizing this synthetic strategy as a promising approach for generating reference materials in drug allergy research and diagnostics.

Spontaneous episodic inflammation in the intestines of mice lacking HNF4A is driven by microbiota and associated with early life microbiota alterations.

The inflammatory bowel diseases (IBD) occur in genetically susceptible individuals who mount inappropriate immune responses to their microbiota leading to chronic intestinal inflammation. Whereas IBD clinical presentation is well described, how interactions between microbiota and host genotype impact early subclinical stages of the disease remains unclear. The transcription factor hepatocyte nuclear factor 4 alpha (HNF4A) has been associated with human IBD, and deletion of Hnf4a in intestinal epithelial cells (IECs) in mice (Hnf4aΔIEC) leads to spontaneous colonic inflammation by 6-12 mo of age. Here, we tested if pathology in Hnf4aΔIEC mice begins earlier in life and if microbiota contribute to that process. Longitudinal analysis revealed that Hnf4aΔIEC mice reared in specific pathogen-free (SPF) conditions develop episodic elevated fecal lipocalin 2 (Lcn2) and loose stools beginning by 4-5 wk of age. Lifetime cumulative Lcn2 levels correlated with histopathological features of colitis at 12 mo. Antibiotic and gnotobiotic tests showed that these phenotypes in Hnf4aΔIEC mice were dependent on microbiota. Fecal 16S rRNA gene sequencing in SPF Hnf4aΔIEC and control mice disclosed that genotype significantly contributed to differences in microbiota composition by 12 mo, and longitudinal analysis of the Hnf4aΔIEC mice with the highest lifetime cumulative Lcn2 revealed that microbial community differences emerged early in life when elevated fecal Lcn2 was first detected. These microbiota differences included enrichment of a novel phylogroup of Akkermansia muciniphila in Hnf4aΔIEC mice. We conclude that HNF4A functions in IEC to shape composition of the gut microbiota and protect against episodic inflammation induced by microbiota throughout the lifespan. IMPORTANCE The inflammatory bowel diseases (IBD), characterized by chronic inflammation of the intestine, affect millions of people around the world. Although significant advances have been made in the clinical management of IBD, the early subclinical stages of IBD are not well defined and are difficult to study in humans. This work explores the subclinical stages of disease in mice lacking the IBD-associated transcription factor HNF4A in the intestinal epithelium. Whereas these mice do not develop overt disease until late in adulthood, we find that they display episodic intestinal inflammation, loose stools, and microbiota changes beginning in very early life stages. Using germ-free and antibiotic-treatment experiments, we reveal that intestinal inflammation in these mice was dependent on the presence of microbiota. These results suggest that interactions between host genotype and microbiota can drive early subclinical pathologies that precede the overt onset of IBD and describe a mouse model to explore those important processes.

Predictors of In-Hospital Mortality in Older Inpatients with Suspected Infection

ObjectivesTo determine the rate and predictors of death in older individuals with suspected infection at any time during hospital stay in a geriatric acute ward and the prognostic ability of different tools [quick Sequential (Sepsis-related) Organ Failure Assessment (qSOFA), Modified and National Early Warning Scores (MEWS) and (NEWS)] in such population. DesignProspective observational single-center cohort study. Setting and ParticipantsAmong patients admitted to an acute geriatric unit of an Italian University Hospital with at least 1 sepsis risk factor, all subjects with suspected infection at admission or during hospital stay (defined as antibiotic prescription and associated culture test) were considered. MethodsA geriatric assessment including comorbidity and social, functional, and cognitive status was performed for each patient. Clinical parameters were evaluated at least twice daily throughout hospital stay; qSOFA, MEWS, and NEWS were derived, with positive cutoffs set at ≥2, ≥5, and ≥7, respectively. ResultsAmong 305 older inpatients (median age 86.0 years, 49.2% female), 21% died during hospital stay. Sepsis was diagnosed in 31.8% of the overall sample and in 64.1% of deceased patients. Deceased patients showed a significantly higher prevalence of prior institutionalization, functional dependence, cognitive impairment, and multimorbidity. The prognostic accuracy of the qSOFA score at infection onset was only fair (area under the receiver operating characteristic curve 0.72; 95% CI, 0.65–0.79, P < .001) and comparable with that of MEWS and NEWS. After multivariable analysis, in-hospital death was positively associated with male sex [odds ratio (OR), 2.11; 95% CI, 1.01–4.44; P = .048] and abnormal white blood cells count (OR, 4.93; 95% CI, 2.36–10.29; P < .001), platelet count (OR, 2.61; 95% CI, 1.10–6.16; P = .029) and serum creatinine (OR, 2.70; 95% CI, 1.30–5.61; P = .008), along with any of the score considered, and negatively associated with autonomy in instrumental activities (OR, 0.78; 95% CI, 0.68–0.90; P < .001). ConclusionsPrognosis in older inpatients with infection or sepsis appears to be determined both by the geriatric characteristics and by the severity of the acute event, expressed by recommended tools and blood test results.

Shortening identification times: comparative observational study of three early blood culture testing protocols.

While early appropriate antibiotic therapy is a proven means of limiting the progression of infections, especially bacteremia, empirical antibiotic therapy in sepsis is ineffective up to 30%. The aim of this study was to compare early blood culture testing protocols in terms of their ability to shorten the delay between blood sampling and appropriate antibiotic therapy. In this french observational study, we compared three blood culture testing protocols. Positive blood cultures were tested using either GenMark ePlex panels (multiplex PCR period), a combination of MRSA/SA PCR, β-Lacta and oxidase tests (multitest period), or conventional identification and susceptibility tests only (reference period). Conventional identification and susceptibility tests were performed in parallel for all samples, as the gold standard. Among the 270 patients with positive blood cultures included, early and conventional results were in good agreement, especially for the multitest period. The delay between a blood culture positivity and initial results was 3.8 (2.9-6.9) h in the multiplex PCR period, 2.6 (1.3-4.5) h in the multitest period and 3.7 (1.8-8.2) h in the reference period (p<0.01). Antibiotic therapy was initiated or adjusted in 68 patients based on early analysis results. The proportion of patients receiving appropriate antibiotic therapy within 48 h of blood sampling was higher in the multiplex PCR and multitest periods, (respectively 90% and 88%) than in the reference period (71%). These results suggest rapid bacterial identification and antibiotic resistance tests are feasible, efficient and can expedite appropriate antibiotic therapy.

Antibiotic Susceptibility of Bacterial Wound Infection: A Cross Sectional Study

Background: Wound infections are one of the most prevalent hospital acquired illnesses and a significant contributor to morbidity. Antibiotic-resistant bacterial infections worsen the condition in developed, developing, and underdeveloped countries. Aim: The purpose of this research was to identify the frequency of various bacterial pathogens and their sensitivity to various kinds of antibiotics in various categories of wound infections in randomly selected Basra City hospitals. Method: Fifty-seven patients with wound infection were involved in this cross sectional study, which was conducted by extracting data from the records of hospital laboratories, where information about bacterial examination of swabs taken by hospital staff from infected wounds and cultured with antibiotic sensitivity test by laboratory staff for treatment purposes. Results and Conclusions: The median age of patients was 38 years, 59.65% of them were males. The most frequent bacteria encountered was Klebsiella pneumonia (24.56%). Single bacterial growth was dominant (86% of cultured bacteria). In antibiotic sensitivity test Gentamycin (7.19%), Ciprofloxacin (5.92%), Amikacin (5.50%), and Tobramycin (5.36%) were the most frequent antibiotics tested, while Cefotaxime, Ceftriaxone, Clarithromycin, and Nalidixic acid were the least used. The highest sensitivity shown by the cultured bacteria was to Tigecycline (92.86%), Lenizoild (90.91%), and Teicoplanin, (80.00%), although they had not been tested widely. While, the antibiotics to which the cultured bacteria did not show any sensitivity were Lomefloxacin (0.00), Ceftriaxone (0.00), and Nalidixic Acid (0.00). Also, the antibiotics to which there had been high resistance were Piperacillin (17.14%) and Minocycline (13.64%).

Identification of genetic variations related to pathogenicity by whole genome sequencing of Listeria monocytogenesSMFM2019‐FV16 isolated from enoki mushroom

AbstractIn this study, the characteristics of Listeria monocytogenes isolated from enoki mushroom (Flammulina velutipes) collected from May to July 2019 were analyzed. The isolates were analyzed for strain characteristics, hemolysis, antibiotic resistance, heat resistance, and virulence genes (inlA, inlB, actA, plcB, and hlyA) were analyzed, and whole genome sequencing (WGS) analysis was performed for the strain with the highest risk. Seven isolates were obtained from some enoki mushroom samples. All isolates were β‐hemolytic and had virulence genes. Antibiotic resistance test showed multi‐drug resistance in L. monocytogenes strain SMFM2019‐FV15 and SMFM2019‐FV16. L. monocytogenes SMFM2019‐FV16 showed higher heat resistance than the other isolates. According to the results L. monocytogenes SMFM2019‐FV16 was selected as the strain with the highest risk. WGS for L. monocytogenes SMFM2019‐FV16 showed that it had 14 antibiotic resistance genes and 43 virulence genes, and 35 single nucleotide variants in the 43 virulence genes were observed. These results indicate that these genetic variations might be related to the high risk of L. monocytogenes SMFM2019‐FV16.

Pathogenic Bacteria and Their Antibiotic Resistance Patterns in Milk, Yoghurt and Milk Contact Surfaces in Debre Berhan Town, Ethiopia.

Bacterial contamination of milk is a primary culprit for causing foodborne illnesses, presenting a significant health hazard for millions of individuals around the globe. The level and variety of microorganisms present in raw milk determine its degree of contamination and the potential health risks it poses. A cross-sectional survey was conducted from February to August. A questionnaire was used to collect data on socio-demographic characteristics and hygiene practices from milk distributors and traders. Raw milk, yoghurt, swabs from milk containers and drinking cups were collected and processed for bacterial isolation and identification, antibiotic susceptibility testing, MDR screening and confirmation, ESBL screening and confirmation. Finally, all data were pooled and analyzed using SPSS software version 25. A total of 120 samples of fresh milk, yogurt and cotton swabs from milk containers and cups were collected. A total of 80 bacterial isolates were isolated from 120 samples. Among the bacteria isolated, S. aureus 17 (21.3%), E. coli 17 (21.3%), S. epidermidis 14 (17.5%), Klebsiella spp. 9 (11.3%) and Salmonella spp. 7 (8.8%) were detected most often. High rate of contamination was observed in fresh milk 23 (28.8%) and yogurt 23 (28.8%). All isolates were resistant to at least one antibiotic tested. Comparatively, high rates of resistance were observed in all isolates to the most commonly prescribed antibiotics in Ethiopia. However, lower rates of resistance have been observed for recently introduced antibiotics in Ethiopia. Of the isolates, 20 (25.0%) were resistant to eight or more antibiotics. While 16 (20.0%), 12 (15.0%), 9 (11.3%) isolates were resistant to two, three and five antibiotics, respectively. Of the bacteria isolated, 52/80 (65.0%) were MDR, 25/49 (51.0%) were screened for ESBL production, and 20/49 (40.8%) isolates were confirmed as ESBL producer. This study showed a high rate ofbacterial isolates along with MDR and ESBL-producing strains in raw milk, yoghurt, milk container swabs and drinking cup swab samples, associated with poor hygiene and sanitation practices.

Assessment of the safety and probiotic properties of Lactobacillus delbrueckii DMLD-H1 based on comprehensive genomic and phenotypic analysis

Lactobacillus delbrueckii is widely used in the fermentation industry. Previously, we identified Lactobacillus delbrueckii DMLD-H1, a strain of Lactobacillus delbrueckii subsp. bulgaricus, from traditional Chinese fermented milk. In this research, we sequenced the complete genome of DMLD-H1, which contains 1,836,627 bp in length with a total of 1947 genes and an average G + C content of 49.86%. In total, 103 carbohydrate metabolism genes are annotated in the KEGG database, and it is showed that DMLD-H1 has the ability to transport lactose, glucose, fructose, and mannose. Antibiotic resistance genes, genes encoding toxins and virulence factor genes are absent in risk-associated sequences of DMLD-H1. We also confirm its safety by indole assay, nitroreductase assay, and antibiotic resistance tests. A wide range of stress-related proteins may contribute to the survival of DMLD-H1 in the gastrointestinal environment, including oxidative stress, pH, bile salts, and temperature stress. The large number of adhesion proteins and stress response genes identified in DMLD-H1 in the genome-wide analysis, as well as phenotypic experiments including resistance to bile salts and acid, antioxidant, antimicrobial and self-cohesion activity, exhibited its excellent probiotic properties. This study demonstrates that DMLD-H1 can be a candidate fermentative agent in fermented dairy products.

Antimicrobial Activity Test of Medicinal Plant Extract Using Antimicrobial Disc and Filter Paper

Plant extracts contain secondary metabolites such as flavonoids and phenolic compounds with antibiotic activity. Antibiotic activity test can be done by using the Kirby-Bauer disc method which the antibiotic activity is indicated by the formation of a clear zone. This research was conducted using extracts of Moringa oleifera leaves and Opuntia cochenillifera cladode extracted using ethyl acetate as a solvent. Antibiotic activity test against Staphylococcus aureus bacteria was done in Mannitol Salt Agar and Luria Bertani Agar media. The Kirby-Bauer discs used are Antimicrobial Disc Oxoid® and Filter Paper. The results of this study show that the use of the Antimicrobial Disc Oxoid® and Filter Paper shows no statistical difference in clear zone results (t-value = 0,45; p-value = 0,655; with α = 95%). While the Clear Zone results on Mannitol Salt Agar gave better results than Luria Bertani Agar and were statistically significant (t-value = 2,46; p-value = 0,02; with α = 95%). These findings indicate that filter paper can be an inexpensive alternative for the antibiotic test with no significantly different result compared to commercial antibiotic disc. However, an antibiotic test against Staphylococcus aureus is better done on Mannitol Salt Agar (MSA) compared to Luria Bertani Agar (LBA).

Streptococcus angriness isolated from Patients with Acute Infection following Surgical Tooth Extraction

In this study, 250 individuals with acute infection following surgical tooth extraction were treated at a Hilla dental clinic and cultivated at 37°C for 18–24 hours. They cultured on several selective medium at 37°C for 18–24 hours. Identification of Streptococcus anginosus was based on colonial morphology, microscopically, and biochemical tests, and all scientific specimens were successful cultures. Of 250 specimens, only 25(10%) were biochemically identified as Strep. anginosus, while 225(90%) were associated with other microorganisms. Hemolysin-producing Strep. anginosus isolates have been studied. 10(66.66%) isolates produced hemolysin in blood agar that formed a clearance sector around the colonies and a streak on the plate after 24 hours of incubation at 37°C. Strep. anginosus isolates were also tested for siderophores production, 5(33.33%) Strep. anginosus isolates produce siderophores. All bacterial isolates provide protease to hydrolyze protein. After 24 hours of incubation, all Strep. anginosus isolates were able to hydrolyze protein using protease enzyme (100%) when tested using M9 (supported by 20% glucose and 1% csaien). Adding 3ml of 5% Trichloroacetic acid gave the colony a clean hallo. Quantitative biofilm development tests were performed in a microtiter using Trypticase Soy Broth with 1% glucose. To improve accuracy, this assay was done three times. All Strep. anginosus isolates were biofilm former (100%), 12/15(80%) were strong biofilm formers, and 3/15 (20%) were mild biofilm formers. However, the antibiotic disc diffusion test using six clinically important antibiotics showed that most Strep. anginosus isolates were extremely resistant to the antibiotics, especially the ?-lactams, including Amoxicillin 13(86.6%), Cefixime 12(80%), Ceftriaxone 12(80%), Meropenem, 11(73.33%) Cefotaxime 10(66.66%), and Imipenem 9(60%).

Prevalence and Antibiotic Resistance Pattern of Diarrheagenic Escherichia coli Pathotypes Among Children under 5 Years in Khuzestan, Iran

Background: Diarrhea is a life-threatening cause of high mortality, especially among children living in areas with poor sanitation. Enterobacteriaceae is one of the serious causes of bacterial diarrhea in children and adults. In this family, infection with diarrheagenic Escherichia coli (DEC) pathotypes in children is associated with extensive health risks and is of particular importance. In this study, we compared the distribution of pathotypes, epidemiological patterns, and antibiotic resistance of DEC in two diarrheal and non-diarrheal groups among children less than 5 years. Methods: In this study, 303 stool samples were collected from patients admitted to Golestan hospitals in Ahvaz and Dr. Ganjavian in Dezful, Khuzestan. To this end, 201 samples from children with diarrhea (case group) and 102 samples from healthy children (control group) were examined. DEC was characterized by polymerase chain reaction (PCR) for each stool sample, and DEC isolates were tested with antibiotic resistance tests against different antibiotic agents to identify the prevalence of multidrug-resistant (MDR) strains in both groups. Results: DEC was found in 24% (48 out of 200) of the children with diarrhea and 3.8% (4 out of 103) of the healthy children. Enteroaggregative E. coli (EAEC) was the DEC most frequently associated with diarrhea (32 out of 48, 66.6%), which was followed by enteropathogenic E. coli (EPEC) 22.9% (11 out of 48, 22.9%), and enterotoxigenic E. coli (ETEC) (5 out of 48, 10.4%) from children with diarrhea. Four DEC isolates were identified in healthy children: EAEC (2 out of 4, 50%) and EPEC (2 out of 4, 50%) in the healthy group, but no enteroinvasive E. coli (EIEC) or enterohemorrhagic E. coli (EHEC) strains were found in both groups in this study group. In general, DEC isolates exhibited high resistance to ceftriaxone and cefotaxime, and 33 (63.4%) isolates of DEC were MDR. Conclusion: A high prevalence of DEC strains was observed in the group of children with diarrhea and healthy children. Accordingly, further attention should be paid to continuous monitoring of the prevalence and pattern of antibiotic resistance of diarrheal bacterial isolates among children and the whole community.

Should Penicillin Allergy Testing Be Included as Part of Preoperative Testing?

Penicillin allergy is the most commonly reported drug allergy in the United States. Patients labeled with penicillin allergy are at risk of receiving broad-spectrum antibiotics for surgical site infection prophylaxis, which can lead to increased antibiotic resistance, higher morbidity, suboptimal antibiotic therapy, and higher medical costs. This study aimed to determine the true prevalence of penicillin allergy among surgical patients and to decrease the unnecessary use of broad-spectrum antibiotics. A retrospective chart review was performed of patients who underwent urogynecologic surgery in 2017. In 2018, a quality initiative was started, and all patients reporting penicillin allergies were offered antibiotic allergy testing as part of their preoperative testing. In 2017, 15% of patients reported penicillin allergy and 52% of them received surgical prophylaxis with broad-spectrum antibiotics. In 2018, 463 patients underwent surgery, 55 of whom reported penicillin allergy and were offered penicillin allergy testing. 35 (64%) agreed to proceed with testing, and of those tested, 33 (94%) tested negative for penicillin allergy. 94% of patients with stated penicillin allergy who consented to allergy testing proved to have negative test. Penicillin allergy testing should be considered as part of preoperative management.

Grafted chitosan thin films of various degrees of acetylation as a reusable platform for the investigation of biological interactions

Surface treatment by adhesive polymers is a promising solution to immobilize and study bacteria cells through microscopic assays and, for example, control their growth or determine their susceptibility to antibiotic treatment. The stability of such functional films in wet conditions is crucial, as the film degradation would compromise a persistent use of the coated devices. In this work, low roughness chitosan thin films of degrees of acetylation (DA) ranging from 0.5 % to 49 % were chemically grafted onto silicon and glass substrates and we have demonstrated how the physicochemical properties of the surfaces and the bacterial response were DA-dependent. A fully deacetylated chitosan film presented an anhydrous crystalline structure while the hydrated crystalline allomorph was the preferred structure at higher DA. Moreover, their hydrophilicity increased at higher DA, leading to higher film swelling. Low DA chitosan-grafted substrate favored bacterial growth away from the surface and could be envisioned as bacteriostatic surfaces. Contrarily, an optimum of Escherichia coli adhesion was found for substrates modified with chitosan of DA = 35 %: these surfaces are adapted for the study of bacterial growth and antibiotic testing, with the possibility of reusing the substrates without affecting the grafted film – ideal for limiting single-use devices.

ANTIBIOTICS SENSITIVITY TEST DIFFUSION AND DILUTION METHODS

An antibiotic sensitivity test is a method to test the response of bacteria to antibiotics. This study aims to determine the effectiveness of an antibiotic against microbial activity. The sensitivity test was conducted with two methods, namely, the diffusion method and the dilution method. The diffusion method was performed using paper discs (Kirby-Bauer) against Escherichia coli and Shigella sonnei bacteria with amoxicillin, neomycin, and sulfonamide antibiotics. The data required is the diameter of the inhibition zone. Results showed that Escherichia coli was sensitive to amoxicillin but resistant to sulfonamide and neomycin. Meanwhile, Shigella sonnei was resistant to amoxicillin, neomycin, and sulfanilamide. Furthermore, the dilution method was performed to test the potency of amoxicillin against Escherichia coli bacteria using the liquid dilution method. The data required were test tubes with liquid media that showed no turbidity. The results showed that the minimal inhibitory concentration of amoxicillin against Escherichia coli was 0.25%. Based on the results of the antibiotic sensitivity test using the diffusion and the dilution methods, it can be concluded that amoxicillin has high effectiveness against Escherichia coli bacteria with a minimum inhibitory concentration of 0.25%, while Shigella sonnei is resistant to the antibiotics tested.

Effect of Enterococcus avium and Enterococcus casseliflavus supernatant and pellet on Klebsiella pneumoniae biofilm formation

Enterococcus is cocci shaped, gram positive, oxidase and catalase negative, facultatively anaerobic, and does not produce spores. It is one of the principal genera that belong to the group of ‘lactic acid bacteria’ (LAB), which also includes Streptococcus and Lactobacillus. The study aimed to detect Enterococcus spp. bacteria using molecular diagnostics .Twenty-one isolates (21%) from 100 samples belonging to Enterococcus spp. were obtained. Three isolates belonging to (two) Enterococcus avium (9.52%) one of them isolated from Kaymak and the other from yoghurt, the other one was (one) Enterococcus casseliflavus (4.76%) which isolated from Ricotta (Made by buffalo milk). After diagnosing by Vitek-2 system of Klebsiella pneumoniae bacteria and detecting its biofilm formation by ‘Congo Red Agar’ method with antibiotic test, the effect of the Enterococcus avium and Enterococcus casseliflavus (supernatants and pellets) on its biofilm formation was tested. Moreover, when compare; to the control group, the effect was highly ‘significant’ (p.0.0069).

Knowledge, Attitude, and Practice of Antibiotic Allergy Testing Among Nurses in Sulaimani, Iraq

Background: One of the major causes of iatrogenic mortality and morbidity is drug allergy. Drug allergies continue to be a major problem for medical professionals right now. For the precise diagnosis of both immediate and delayed medication hypersensitivity, intradermal sensitivity testing is crucial.Objectives: to assess the nurse’s knowledge, attitude and, practice on intradermal method of antibiotic sensitivity test in Sulaimani, Iraq.Materials and Methods: A quantitative, descriptive, and observational design was used to collect information from nurses at Shar Teaching Hospital from various hospital departments. A convenient sampling method was employed for all 90 nurses from January 2022 to August 2022. Data collection was carried out through a structured interview questionnaire aimed at gathering the nurses’ general characteristics, a nurses’ knowledge questionnaire, and an observational checklist to assess the nurses’ practices regarding the Antibiotic Allergy Test.Results: The results indicated a positive attitude and a moderate knowledge of the antibiotic allergy test. A significant correlation existed between attitude scores and age (p=0.03) and degree (p=0.01) but not between demographic characteristics and general knowledge (p&gt;0.05). However, prior research revealed a significant correlation between knowledge and attitude and the training program.Conclusion: The knowledge and attitude of nurses about intradermal testing were moderate. To help nurses better comprehend and fill in the gaps in the practice of antibiotic allergy testing, extensive training and education are therefore required.