Multi-locus sequence typing of Escherichia coli isolated from clinical samples in Jordan.

INTRODUCTION: Escherichia coli (E. coli) is the major cause of extraintestinal infections in the urinary tracts and bloodstream in humans in the community and health care institutions. Several studies on the genetic characterization of E. coli among clinical and environmental isolates were performed and revealed a wide diversity of sequence types (STs). In Jordan, phenotypic and genetic features of E. coli were extensively studied but there is still a need to identify the STs that inhabit the community. METHODOLOGY: In this study, multi-locus sequence typing (MLST) was performed on archived clinical E. coli isolates collected from different hospitals in Jordan and the identified STs were extensively analyzed. RESULTS: Genotyping of 92 E. coli isolates revealed 34 STs and 9 clonal complexes. The frequencies of STs ranged between 1 to 23 observations. The most frequent STs among E. coli isolates were ST131 (n = 23), ST69 (n = 19), ST998 (n = 7), ST2083 (n = 5), and ST540 (n = 4). These five ST accounted for up to 60% of the 92 E. coli isolates. Based on the MLST database, the STs reported in this work were world widely recognized in humans, animals, and in the environment. CONCLUSIONS: This study has elaborated more knowledge about the genotypes of E. coli in Jordan, with recommendations for future studies to correlate its genotypes with virulence and resistance genes.

The efficacy of biosynthesized silver nanoparticles against Pseudomonas aeruginosa isolates from cystic fibrosis patients.

The high antibiotic resistance of Pseudomonas aeruginosa (PA) makes it critical to develop alternative antimicrobial agents that are effective and affordable. One of the many applications of silver nanoparticles (Ag NPs) is their use as an antimicrobial agent against bacteria resistant to common antibiotics. The key purpose of this research was to assess the antibacterial and antibiofilm effectiveness of biosynthesized Ag NPs against six biofilm-forming clinically isolated strains of PA and one reference strain (ATCC 27853). Ag NPs were biosynthesized using a seed extract of Peganum harmala as a reducing agent. Ag NPs were characterized by Ultraviolet-visible (UV-Vis) spectroscopy and scanning transmission electron microscopy (STEM). The effect of Ag NPs on biofilm formation and eradication was examined through micro-titer plate assays, and the minimal inhibitory (MIC) and minimum bactericidal (MBC) concentrations determined. In addition, real-time polymerase chain reactions (RT-PCR) were performed to examine the effects of Ag NPs on the expression of seven PA biofilm-encoding genes (LasR, LasI, LssB, rhIR, rhII, pqsA and pqsR). The biosynthesized Ag NPs were spherically-shaped with a mean diameter of 11 nm. The MIC for each PA strain was 15.6 µg/ml, while the MBC was 31.25 µg/ml. All PA strains exposed to Ag NPs at sub-inhibitory concentrations (0.22-7.5 µg/ml) showed significant inhibitory effects on growth and biofilm formation. Biomass and biofilm metabolism were reduced dependent on Ag NP concentration. The expression of the quorum-sensing genes of all strains were significantly reduced at an Ag NP concentration of 7.5 µg/ml. The results demonstrate the extensive in-vitro antibacterial and antibiofilm performance of Ag NPs and their potential in the treatment of PA infection. It is recommended that future studies examine the possible synergy between Ag NPs and antibiotics.

Antimicrobial Resistance Molecular Mechanisms of Helicobacter pylori in Jordanian Children: A Cross-Sectional Observational Study.

BACKGROUND: H. pylori antimicrobial resistance causes increasing treatment failure rates among H. pylori gastritis in children. This study investigates the molecular mechanisms of H. pylori antimicrobial resistance among Jordanian children. METHODS: Demographic, clinical, and laboratory data were recorded for children referred to Prince Hamzah Hospital. Clarithromycin, Metronidazole, and Levofloxacin susceptibility were tested via E-test. Clarithromycin-related mutations were investigated using Real-Time (RT)-PCR and Levofloxacin resistance was analyzed with DNA sequencing of the gyrA gene. RESULTS: 116 children were recruited, including 55.2% females and 55.2% in the age range of 10.1 to 14 years. A total of 82.7% were naïve to eradication therapy. H. pylori positivity was 93.9%, 89.6%, 61.7%, and 84.3% according to Rapid Urease Test, histology, culture, and RT-PCR, respectively. Resistance rates were 25.9% for Clarithromycin, 50% for Metronidazole, and 6.9% for Levofloxacin via E-test. A2142G or A2143G or a combination of both mutations concerning Clarithromycin resistance were documented in 26.1% of samples, while mutations in gyrA gen-related to Levofloxacin resistance were reported in 5.3% of samples. Antibiotic resistance was significantly affected by abdominal pain, anemia, hematemesis, and histological findings (p < 0.05). CONCLUSION: H. pylori resistance was documented for Metronidazole and Clarithromycin. RT-PCR for H. pylori identification and microbial resistance determination are valuable alternatives for cultures in determining antimicrobial susceptibility.

Immunoglobulins response of COVID-19 patients, COVID-19 vaccine recipients, and random individuals.

BACKGROUND: The development of specific immunoglobulins to COVID-19 after natural infection or vaccination has been proposed. The efficacy and dynamics of this response are not clear yet. AIM: This study aims to analyze the immunoglobulins response among COVID-19 patients, COVID-19 vaccine recipients and random individuals. METHODS: A total of 665 participants including 233 COVID-19 patients, 288 COVID-19 vaccine recipients, and 144 random individuals were investigated for anti-COVID-19 immunoglobulins (IgA, IgG, IgM). RESULTS: Among COVID-19 patients, 22.7% had detectable IgA antibodies with a mean of 27.3±57.1 ng/ml, 29.6% had IgM antibodies with a mean of 188.4±666.0 BAU/ml, while 59.2% had IgG antibodies with a mean of 101.7±139.7 BAU/ml. Pfizer-BioNTech vaccine recipients had positive IgG in 99.3% with a mean of 515.5±1143.5 BAU/ml while 85.7% of Sinopharm vaccine recipients had positive IgG with a mean of 170.0±230.0 BAU/ml. Regarding random individuals, 54.9% had positive IgG with a mean of 164.3±214 BAU/ml. The peak IgM response in COVID-19 patients was detected early at 15-22 days, followed by IgG peak at 16-30 days, and IgA peak at 0-60 days. IgM antibodies disappeared at 61-90 days, while IgG and IgA antibodies decreased slowly after the peak and remained detectable up to 300 days. The frequency of IgG positivity among patients was significantly affected by increased age, admission department (inpatient or outpatient), symptoms, need for oxygen therapy, and increased duration between positive COVID-19 RT PCR test and serum sampling (p˂0.05). Positive correlations were noted between different types of immunoglobulins (IgG, IgM, and IgA) among patients. CONCLUSIONS: Natural infection and COIVD-19 vaccines provide IgG-mediated immunity. The class, positivity, mean, efficacy, and duration of immunoglobulins response are affected by the mechanism of immunity and host related variables. Random community individuals had detectable COVID-19 IgG at ~55%, far from reaching herd immunity levels.

Review on Different Vesicular Drug Delivery Systems (VDDSs) and Their Applications.

BACKGROUND: Colloidal dispersions, also known as vesicular drug delivery systems (VDDSs), are highly ordered assemblies composed of one or more concentric bilayers formed by the self-assembly of amphiphilic building blocks in the presence of water. OBJECTIVE: VDDSs are important to target the entrapped drugs at specific sites inside the body, control the drug release, enhance the drug bioavailability, and reduce undesired side effects. METHODS: There are different types of VDDSs suitable for the entrapment of both hydrophilic and lipophilic drugs. According to the patent composition, VDDSs are classified into lipid-based and nonlipid- based VDDSs. RESULTS: There are different types of VDDSs which include liposomes, ethosomes, transferosomes, ufasomes, colloidosomes, cubosomes, niosomes, bilosomes, aquasomes, etc. Conclusion: This review article aims to address the different types of VDDSs, their advantages and disadvantages, and their therapeutic applications.

Multidrug-Resistant Acinetobacter baumannii in Jordan.

Background: Acinetobacter baumannii is a common cause of multi-drug (MDR)-resistant infections worldwide. The epidemiological and molecular characteristics of MDR-A. baumannii in Jordan is not known. Methods: A. baumannii isolates were collected from 2010 to 2020 from three tertiary hospitals in Jordan. Demographic and clinical data, isolates information, antibiotic susceptibility patterns, phenotypic, and molecular characterization of carbapenem resistance genes were performed. Results: A total of 622 A. baumannii isolates were collected during the study period. Most isolates were from males, aged 18−60 years, Jordanian, from infected wounds, and were patients in surgery or critical care units. Among patients from whom A. baumannii was isolated, associated risk factors for MDR were adults over 60, males, critically ill patients and infected wounds (OR 4.14, 2.45, 10, 7, respectively, p < 0.0001). Incidence rates from 2010 to 2015 showed a slight increase in MDR (3.75/1000 to 4.46/1000). Resistance patterns indicated high resistance for most cephalosporins, carbapenems, and fluoroquinolones, moderate resistance for trimethoprim/sulfamethoxazole and ampicillin/sulbactam, low resistance for aminoglycosides and tetracyclines, while colistin and tigecycline, have the lowest resistance rates. 76.8% of A. baumannii isolates were MDR and 99.2% were carbapenem-resistant. All isolates were positive for the OXA-51 gene (100%), 98.5% were positive for the OXA-23 gene, 26.6% for the VIM gene, while KPC and IMP genes were almost not detected (0% and 0.8% respectively). Conclusions: This is the first large, multicentric, prolonged study that provides insights into A. baumannii infections in Jordan. Attention to patients at higher risk is important for early identification. Colistin and tigecycline were the most effective antimicrobials.

Cefixime and cefixime-clavulanate for screening and confirmation of extended-spectrum beta-lactamases in Escherichia coli.

INTRODUCTION: Detection of Extended-Spectrum Beta-Lactamases (ESBLs) depends on screening for resistance to certain cephalosporins, confirmation with selective ESBL inhibitors, and ESBL genes detection. New tests are required for accurate ESBL detection. AIMS: To test the ability of cefixime (CFM) and cefixime-amoxicillin/clavulanate (CFM-AMC) as a screening and confirmatory test for ESBL identification. METHODS: 246 clinical isolates of Escherichia coli were tested by an ESBL screening test, a double-disk synergy test (DDST), a disk replacement test, the Vitek 2 ESBL test, and an ESBL genes test by PCR. CFM ESBL Screening was performed by disk diffusion, while CFM-AMC confirmation was performed by DDST and a disk replacement test. RESULTS: 246 E. coli clinical isolates from two referral hospitals were collected over 2 years. The mean age ± standard deviation of patients was 43.8 ± 27.7 years and 76.8% were females. Resistance rates to penicillins, first, second, and third generation cephalosporins, and monobactams were very high at 97%, 84%, 100% and 97%, respectively. ESBL screening was positive in 81.3% of isolates, DDST was positive in 74.8%, disk replacement was positive in 79%, Vitek 2 ESBL test was positive in 67.3%, and ESBL genes were detected in 85.8% of isolates (CTX-M 75%, TEM 42.5%, SHV 4.6%). Compared to genotyping, screening with CFM achieved 87.7% sensitivity and 64.7% specificity. CFM-AMC DDST achieved 75.8% sensitivity and 75.4% specificity, and CFM-AMC disk replacement had 73% sensitivity and 70% specificity. CONCLUSIONS: High prevalence of ESBLs was noted among E. coli isolates, dominated by CTX-M genotype. ESBL screening and confirmation using CFM and CFM-AMC is a new and accurate method for ESBLs detection.

Effective Oral Combination Treatment for Extended-Spectrum Beta-Lactamase-Producing Escherichia coli.

Background: Extended-spectrum beta-lactamase-producing Escherichia coli (ESBL-EC) is increasing worldwide. The drugs of choice for treatment of ESBLs are parenteral carbapenems. The aim of this study was to evaluate the in vitro and in vivo efficacy of a new combination of oral cephalosporins and amoxicillin/clavulanate in treatment of ESBL-EC. Methods: A total of 150 ESBL-EC samples were collected over 1 year from two referral centers. Synergistic studies of cephalosporins and amoxicillin/clavulanate were performed in vitro using disk approximation and disk replacement methods. Combination treatment was assessed in vivo on 20 ESBL-EC urinary tract infection (UTI) patients. Results: ESBL-EC isolates were confirmed in 150 patients with a mean age of 46.67 years, 75.2% of them being women. Antibiotic susceptibility testing of isolates indicated high resistance rate to oral antibiotics. The frequency of positive synergy and mean distance of synergy between cephalosporins and amoxicillin/clavulanate was significantly higher with cefotaxime and cefixime compared with cefpodoxime, cefdinir, and ceftazidime using disk approximation and disk replacement methods (p < 0.05). Addition of amoxicillin/clavulanate enhanced the susceptibility rate with cefixime from 8.6% to 86.3%, significantly higher than with other cephalosporins (p < 0.0005). Cefixime and amoxicillin/clavulanate synergy was not affected by age, gender, hospital, department, sample type, or bacterial load. Eighteen of 20 ESBL-EC-positive UTI patients had a positive in vitro synergy test and complete clinical and microbiological resolution after completion of cefixime and amoxicillin/clavulanate oral treatment course. Conclusions: Cefixime and amoxicillin/clavulanate combination therapy could be an effective oral outpatient treatment option for ESBL-EC. In vitro synergistic testing is simple and predictive of successful treatment.