Low-Level Antibiotic Resistance among Staphylococcus aureus and Gram-Negative Pathogens from Infected Skin and Soft Tissues in Rural Kenya

Introduction: Bacterial skin and soft tissue infections (SSTIs) are a cause of frequent inpatient and outpatient care visits whose causative agents are associated with a high antimicrobial resistance burden. For insights on antimicrobial susceptibilities in a rural setting, we examined specimens from suspected SSTIs from two public health facilities in Kenya. We additionally assessed antibiotic use, appropriateness of empiric therapy and risk factors for SSTI. Methodology: Between 2021 and 2023, 265 patients at Kisii and Nyamira County Referral hospitals were enrolled. Wound swabs/aspirates were collected and processed following standard microbiological procedures. Identification and antimicrobial susceptibility were performed using the VITEK 2 Compact platform. Demographic, clinical, and microbiological data were analyzed with R Statistical software. Results: S. aureus was isolated in 16.2% (43/265) of patients with a methicillin resistance (MRSA) proportion of 14% (6/43). While 13/15 drugs elicited susceptibilities ranging from 84% - 100%, penicillin (16%) and trimethoprim-sulfamethoxazole [TMP-SXT] (23%) yielded the lowest susceptibilities. Escherichia coli (n = 33), Klebsiella pneumoniae (n = 8), Pseudomonas aeruginosa (n = 8), and Citrobacter species (n = 4) were the most commonly isolated gram-negative species. Gram-negative strains showed high susceptibilities to most of the tested drugs (71% - 100%) with the exception of ampicillin (18%), TMP-SXT (33%), and first and second generation cephalosporins. Conclusions: The low MRSA prevalence and generally high antibiotic susceptibilities for S. aureus and gram-negative bacteria present opportunities for antibiotic stewardship in the study setting. Diminished susceptibilities against penicillin/ampicillin and TMP-SXT accord with prevailing local data and add a layer of evidence for their cautious empiric use.

Phytochemicals of Aloe barbadensis miller as Potential Inhibitors of Uropathogenic Escherichia coli for Urinary Tract Infection Therapy: An in Silico Approach

Urinary tract infections (UTIs) are common infections caused by normal skin or rectum bacteria that get into the urethra and infect the urinary tract. Although the infection can affect various parts of the tract, bladder infections are the most prevalent kind. Uropathogenic Escherichia Coli (UPEC) is the most common pathogen associated with UTI development. Therefore, inhibiting the UPEC protein target (PDB ID: 8BVD) appears to be a promising therapeutic strategy. Therefore, in this study, molecular docking and dynamics were conducted to examine the antibacterial activity of Aloe barbadensis miller against UPEC bacteria. The Aloe barbadensis miller natural compounds licochalcone A, palmidin B and palmidin C were downloaded from PubChem with amoxicillin, which was used as a control drug and studied against the target molecule. The potential parameters examined were the docking scores, absorption, distribution, metabolism, excretion, toxicity (ADMET), bioavailability, root mean square deviation (RMSD), root mean square fluctuation (RMSF), hydrogen bonding, radius of gyration, and potential energy of the system. Docking scores showed that all ligands demonstrated an admirable candidature as an inhibitor to 8BVD molecule, and the score hierarchy is licochalcone A (-6.4 kcal/mol), palmidin C (-6.1 kcal/mol), palmidin B (-6.0 kcal/mol), and amoxicillin (-5.9 kcal/mol). All ligands appeared to have good drug-like properties and oral bioavailability. Molecular dynamic studies showed that all ligands exhibited an excellent nominee as inhibitors in their vicinity at 20 ns. However, there is a relatively high fluctuation of palmidin B compared with other compounds, which seems to be more stable. This work suggests that the selected phytoconstituents could be used as inhibitors of the 8BVD protein in the fight against UTIs. However, further investigation on the clinical and experimental validation of UTI treatment’s specific mechanisms and effects is still welcomed.

High mortality associated with gram-negative bacterial bloodstream infection in liver transplant recipients undergoing immunosuppression reduction

BACKGROUND Immunosuppression is an important factor in the incidence of infections in transplant recipient.Few studies are available on the management of immunosuppression(IS)treatment in the liver transplant(LT)recipients complicated with infection.The aim of this study is to describe our experience in the management of IS treatment during bacterial bloodstream infection(BSI)in LT recipients and assess the effect of temporary IS withdrawal on 30 d mortality of recipients presenting with severe infection.AIM To assess the effect of temporary IS withdrawal on 30 d mortality of LT recipients presenting with severe infection.METHODS A retrospective study was conducted with patients diagnosed with BSI after LT in the Department of Liver Surgery,Renji Hospital from January 1,2016 through December 31,2017.All recipients diagnosed with BSI after LT were included.Univariate and multivariate Cox regression analysis of risk factors for 30 d mortality was conducted in the LT recipients with Gram-negative bacterial(GNB)infection.RESULTS Seventy-four episodes of BSI were identified in 70 LT recipients,including 45 episodes of Gram-positive bacterial(GPB)infections in 42 patients and 29 episodes of GNB infections in 28 patients.Overall,IS reduction(at least 50%dose reduction or cessation of one or more immunosuppressive agent)was made in 28(41.2%)cases,specifically,in 5(11.9%)cases with GPB infections and 23(82.1%)cases with GNB infections.The 180 d all-cause mortality rate was 18.5%(13/70).The mortality rate in GNB group(39.3%,11/28)was significantly higher than that in GPB group(4.8%,2/42)(P=0.001).All the deaths in GNB group were attributed to worsening infection secondary to IS withdrawal,but the deaths in GPB group were all due to graft-versus-host disease.GNB group was associated with significantly higher incidence of intra-abdominal infection,IS reduction,and complete IS withdrawal than GPB group(P<0.05).Cox regression showed that rejection(adjusted hazard ratio 7.021,P=0.001)and complete IS withdrawal(adjusted hazard ratio 12.65,P=0.019)were independent risk factors for 30 d mortality in patients with GNB infections after LT.CONCLUSION IS reduction is more frequently associated with GNB infection than GPB infection in LT recipients.Complete IS withdrawal should be cautious due to increased risk of mortality in LT recipients complicated with BSI.

Association between infections caused by multidrug-resistant gram-negative bacteria and mortality in critically ill patients

The incidence of gram-negative multidrug-resistant(MDR) bacterial pathogens is increasing in hospitals and particularly in the intensive care unit(ICU) setting. The clinical consequences of infections caused by MDR pathogens remain controversial. The purpose of this review is to summarize the available data concerning the impact of these infections on mortality in ICU patients. Twenty-four studies, conducted exclusively in ICU patients, were identified through Pub Med search over the years 2000-2015. Bloodstream infection was the only infection examined in eight studies, respiratory infections in four and variable infections in others. Comparative data on the appropriateness of empirical antibiotic treatment were provided by only seven studies. In ten studies the presence of antimicrobial resistance was not associated with increased mortality; on the contrary, in other studies a significant impact of antibiotic resistance on mortality was found, though, sometimes, mediated by inappropriate antimicrobial treatment. Therefore, a direct association between infections due to gram-negative MDR bacteria and mortality in ICU patients cannot be confirmed. Sample size, presence of multiple confounders and other methodological issues may influence the results. These data support the need for further studies to elucidate the real impact of infections caused by resistant bacteria in ICU patients.

Seafood as a Reservoir of Gram-negative Bacteria Carrying Integrons and Antimicrobial Resistance Genes in Japan

PCR and DNA sequencing were used to screen and characterize integrons and resistance genes in Gram-negative bacteria isolated from seafood products in Japan.A total of 215 Gram-negative bacteria were isolated from local and imported seafood samples collected from retail markets in Hiroshima Prefecture.Class 1 integrons containing gene cassettes encoding resistance to trimethoprim

Impact of Polymyxin Resistance on Virulence and Fitness among Clinically Important Gram-Negative Bacteria

Humanity is facing an enormous and growing worldwide threat from the emergence of multi-drug-resistant(MDR)Gram-negative bacteria such as Escherichia coli,Klebsiella pneumoniae,and Acinetobacter baumannii.Polymyxin B and E(colistin)constitute the last-line therapies for treating MDR Gram-negative bacteria.Polymyxin is a cationic antibacterial peptide that can destroy the outer membrane of Gram-negative bacteria.With the increasing clinical application of polymyxin,however,there have been many reports of the occurrence of polymyxin-resistant Gram-negative bacteria.This resistance is mainly mediated by the modification or complete loss of lipopolysaccharide(LPS).LPS is also a virulence factor of Gram-negative bacteria,and alterations of LPS may correlate with virulence.Although it is generally believed that the biological costs associated with drug resistance may enable benign susceptible bacteria to overcome resistant bacteria when antibiotic pressure is reduced,some studies have shown that polymyxin-resistant bacteria are associated with higher virulence and greater fitness compared with their susceptible counterparts.To predict the development of polymyxin resis-tance and evaluate interventions for its mitigation,it is important to understand the relative biological cost of polymyxin resistance compared with susceptibility.The impact of polymyxin resistance mecha-nisms on the virulence and fitness of these three Gram-negative bacteria are summarized in this review.

An Improved Approach for Rapidly Identifying Different Types of Gram-Negative Bacterial Secreted Proteins

Protein secretion plays an important role in bacterial lifestyles. In Gram-negative bacteria, a wide range of proteins are secreted to modulate the interactions of bacteria with their environments and other bacteria via various secretion systems. These proteins are essential for the virulence of bacteria, so it is crucial to study them for the pathogenesis of diseases and the development of drugs. Using amino acid composition (AAC), position-specific scoring matrix (PSSM) and N-terminal signal peptides, two different substitution models are firstly constructed to transform protein sequences into numerical vectors. Then, based on support vector machine (SVM) and the “one to one”?algorithm, a hybrid multi-classifier named SecretP v.2.2 is proposed to rapidly and accurately?distinguish different types of Gram-negative?bacterial secreted proteins. When performed on the same test set for a comparison with other methods, SecretP v.2.2 gets the highest total sensitivity of 93.60%. A public independent dataset is used to further test the power of SecretP v.2.2 for predicting NCSPs, it also yields satisfactory results.

Epidemiological Study of Rapidly Emerging Uropathogens Isolated from Urinary Catheter and Its Influential Demographic Factors Responsible for Contamination

Urinary tract infections (UTI) are very common in all the developed as well as developing countries in which the majority of infections are catheter associated. Catheter associated urinary tract infections (CAUTI) is one of the major causes of hospital acquired infections. The aim of this study is to investigate influential demographic factors responsible for contamination associated with the rate of CAUTI, while taking into account type of urinary catheter used, the most common organisms found, patient diagnosis, age, gender, and comparison with other studies. During the study, 22 uropathogenic species were isolated from the different segments of urinary catheter samples of the patients collected from 12 different hospitals of Amravati city, Maharashtra, India from January 2015 to 2018. Gram negative organisms were the most frequent isolates, with Pseudomonas aeruginosa (16.08%) being the most common followed by Escherichia coli (10%) and Candida albicans accounted for almost 11% of all the uropathogens. It was found that the majority of uropathogens were isolated from the section A (Catheter segment inside the bladder) and section E (Catheter segment connected to drainage tube) of the urinary catheter. The duration of the catheterization plays the major role in the contamination and further infection to continue. It was observed that the female catheterized patients are more prone to the contamination and infection as compared to male catheterized patient. The antibiotic sensitivity pattern indicates that MAR (Multiple Antibiotic Resistance) index was more than 0.2 for almost all the uropathogens tested concluding that there is antibiotic stress on uropathogens and rate of resistance increased rapidly. Also it was found that there was a statistically significant association between the duration of catheterization, type of disease, age of patient and type of catheter with respect to gender.

Metallo-β-lactamase producing nonfermentative gram-negative bacteria:An increasing clinical threat among hospitalized patients

Objective:To detect and evaluate the various methods for metallo-β-lactamases(MBL) production in Pseudomonas aeruginosa(P.aeruginosa) and Acinetobacter species.Methods:A total of 109 P.aeruginosa and 85 Acinetobacter species were screened for imipenem resistance by Kirby- Bauer disc diffusion methods.Detection of MBL production was(lone by imipenem-EDTA combined disc test,double disc synerygy test(DDST) and imipenem-EDTA MBL E test.Results: A total of 63(57.8%) strains of P.aeruginosa and 46(54.1%) strains of Acinetobacter spp.were found to be resistant to imipenem.Of the 63 imipenem resistant P.aeruginosa tested for MBL production.44(69.89;) were found to be positive and among 46 imipenem resistant Acinetobacter. 19(41.3%) were shown to be the MBL producers.Conclusions:Imipenem-EDTA combined disc test and MBL E test are equally effective for MBL detection in both P.aeruginosa and Acinetobacter spp.,but given the cost-constraints,combined disc can be used as a convenient screening method in the clinical microbiology laboratory.

Immunogenomics for identification of disease resistance genes in pigs: a review focusing on Gram-negative bacilli

Over the past years, infectious disease has caused enormous economic loss in pig industry. Among the pathogens, gram negative bacteria not only cause inflammation, but also cause different diseases and make the pigs more susceptible to virus infection. Vaccination, medication and elimination of sick pigs are major strategies of controlling disease. Genetic methods, such as selection of disease resistance in the pig, have not been widely used. Recently, the completion of the porcine whole genome sequencing has provided powerful tools to identify the genome regions that harboring genes controlling disease or immunity. Immunogenornics, which combines DNA variations, transcriptorne, immune response, and QTL mapping data to illustrate the interactions between pathogen and host immune system, will be an effective genomics tool for identification of disease resistance genes in pigs. These genes will be potential targets for disease resistance in breeding programs. This paper reviewed the progress of disease resistance study in the pig focusing on Gram-negative bacilli. Major porcine Gram-negative bacilli and diseases, suggested candidate genes/pathways against porcine Gram-negative bacilli, and distributions of QTLs for immune capacity on pig chromosomes were summarized. Some tools for immunogenomics research were described. We conclude that integration of sequencing, whole genome associations, functional genomics studies, and immune response information is necessary to illustrate molecular mechanisms and key genes in disease resistance.

Epidemiological Characteristics, Resistance Patterns and Spread of Gram-Negative Bacteria Related to Colonization of Patients in Intensive Care Units

Our aim was to determine the epidemiological characteristics, the resistance patterns and the spread of Gram negative bacteria related to colonization of patients in adult Intensive Care Units. Methods: A prospective cohort of patients colonized and/or infected with Gram negative bacteria was conducted at two adult ICUs from hospitals in Brazil (April 2012 to February 2013). Nasal, groin and perineum swabs were performed. Samples were incubated on MacConkey and cetrimide agar (48 h at 37℃) and identification tests (Vitek-BioMérieux), antibiogram (Bauer-Kirby method), Carba NP test, Polymerase Chain Reaction (PCR) and sequencing were performed. The patterns of resistant microorganisms were compared by rep-PCR (Diversilab). Results: There were 53 cases of colonization. In these cases, we identified imipenem-resistant Acinetobacter baumannii (51%), Pseudomonas aeruginosa (32%), Klebsiella pneumoniae ESBL (38%) or imipenem resistant (5.6%). The use of antimicrobials and medical devices were related to colonization (p The resistance patterns expressed by Klebsiella pneumoniae were ESBL (CTX-M, SHV e TEM) and KPC2. A verified profile of Acinetobacter baumannii was related to OXA-23 and OXA-253 (OXA-143 variant). The profiles ESBL and KPC2 expressed by Klebsiella pneumoniae were distributed between the both ICUs. The distribution of OXA-23 and OXA-253 was verified only in one ICU. The similarity of strains ranged from 80% to 95%, highlighting the horizontal transference of these microorganisms.

Detection of 16S rRNA Methylase Genes in Gram-Negative Bacilli Isolated from Hospitals in Changchun, China

Methylation of 16S rRNA is an important mechanism of aminoglycoside resistance among gram-negative pathogens. In this report, 16S rRNA methylase genes were amplified using PCR among gram-negative bacillus isolates from hospitals in the Changchun area of China and 16S rRNA methylase genotypes (armA, rmtB, rmtA, rmtC, rmtD, and npmA) were identified by direct sequencing. Fifty of the isolates (43.1%) harbored 16S rRNA methylase genes. The common 16S rRNA methylase genes were armA and rmtB (12.1% and 31.0%, respectively), whereas the rmtA, rmtC, rmtD, and npmA genes were absent from the sample. It suggests that the predominant 16S rRNA methylase genes among gramnegative bacilli in the Changchun area are armA and rmtB.

Prevalence and Antimicrobial Resistance of Gram-Negative Bacteria Isolates in Shellfish Samples from Two River Estuaries in South-South Nigeria

Antibiotic resistant bacteria pathogens remain the leading cause of shellfish borne diseases and a major health threat to humans worldwide. The objectives of this study were to isolate, identify, and determine the antibiotic resistance patterns of Gram-negative bacteria from shellfish. We analyzed a total of 540 shellfish (117 clams, 88 oysters, and 136 periwinkles) samples collected from different vendors at Iko and Douglas Creeks in Akwa Ibom State, South-South Nigeria. Conventional cultural techniques, morphological, biochemical characteristics, and PCR amplification were used to identify the bacterial isolates. Antibiotic susceptibility tests (Kirby-Bauer disk diffusion method) and ESBL phenotype (disk) of the isolates were performed. One hundred and thirty-five (135) Gram-negative bacteria comprising 5 genera and 14 species were detected at a prevalence of: Alcaligenes faecalis TRB-7 38 (28.2%), Pseudomonas oryzihabitans strain KCB005 16 (11.9%), Paenalcaligenes retgerii strain B5 12 (8.9%) Pseudomonas aeruginosa JB2 10 (7.4%), Providencia stuartii DMC-28b 9 (6.7%), Alcaligenes species TLT151 8 (5.9%), Pseudomonas aeruginosa CIFRI DTSB1 7 (5.2%), Paenalcaligenes species UN24 7 (5.2%), Alcaligenes faecalis BT10 7 (5.2%), Vibrio species strain PrVy108 6 (4.4%), Pseudomonas xiamenensis C10-2 5 (3.7%), Providencia vemicola Bu15_38 4 (2.9%), Pseudomonas anguillisceptica 4029 3 (2.2%), and Pseudomonas aeruginosa N15-01092 3 (2.2%). All tested isolates showed various degrees of resistance to the thirteen antimicrobials evaluated. High levels of resistance (100%) to cefepime and imipenem were expressed by all isolates except the Providencia species. For the EBSL indicators, all isolates apart from Alcaligenes species were resistant (100%) to ceftriaxone. All Vibrio species were susceptible to norfloxacin, nalidixic acid, and ceftazidime. The identification of antibiotic resistant Gram-negative bacteria (GNARB) from shellfish in this study highlights the risk of disseminated multi-drug resistance—a serious public health concern.

Detection of the Production of Klebsiella Pneumoniae Carbapenemase, New Delhi Metallo-Beta-Lactamase and Oxacillinase-48-Type Carbapenemases by Gram-Negative Bacilli in Resource-Limited Setting

Background: The increasing resistance of bacteria to various antibiotics is a worldwide public health issue. Carbapenems that have elicited great hope in treating infections caused by multidrug-resistant germs have seen their efficacy narrowed over time with the emergence of other novel resistance mechanisms, notably the production of Carbapenemases. Methods: A prospective cross-sectional study was conducted from May 2017 to May 2018 in Douala (Cameroon) to detect carbapenemase-producing Gram-negative bacilli. Isolated strains were identified using the Vitek2TM system. Antimicrobial susceptibility testing was performed using the Kirby-Bauer disk diffusion method on agar plates with 20 selected commercially available antibiotic discs. The bacterial strains were tested for the production of three Carbapenemases (OXA-48, NDM, KPC), using an immuno-chromatographic technique, with the “RESIST-3 O.K.N. K-SeT” rapid detection kit. Results: During the study period, 1687 strains of Gram-negative bacilli were isolated in selected laboratories with a total of 200 multi-resistant strains identified (11.9%). Among the multi-resistant strains, E. coli was the species most represented in Enterobacteriaceae (27.5%) followed by K. pneumoniae (15.5%) and the non-fermenting Gram-negative bacilli were predominantly P. aeruginosa (20.5%). These strains mainly came from urine and pus, i.e. 41% and 32% respectively. Thirty-two (16%) strains produced one of the Carbapenemases with a higher frequency at the General Hospital (84%). NDM-type carbapenemase was the most frequently identified (8.5%), OXA-48 type 7.5%, and no KPC production was observed. Among the Enterobacteriaceae 22.9% produced Carbapenemases and only 5.1% of the non-fermenting bacilli produced these enzymes. The isolates strains were completely resistant to all antibiotics except Amikacin and Fosfomycin. The strains producing the NDM-type carbapenemase showed higher rates of resistance to almost all of the antibiotics tested. Conclusion: Multidrug-resistant strains are experiencing an increase in evolution. The apparition of strains producing Carbapenemases prominently, the NDM and OXA-48 favor this increase. The activities of antibiotics with high efficacies on these strains are low.

Impact of an Antimicrobial Stewardship Program Initiative on Antibiotic Optimization in Patients with Gram-Negative Bacteremia

The purpose of this study was to critically evaluate the impact of an institutional blood culture notification protocol called RAIDS （rapid administration of antimicrobials by an infectious diseases specialist） on time to optimization of antimicrobial therapy in hospitalized patients with gram-negative bacteremia. Time to antibiotic optimization was compared in patients with gram-negative bacilli isolated from blood cultures obtained from March-May 2011 （pre-RAIDS） versus March-May 2013 （post-RAIDS）. The results show that patients in the pre-RAIDS study group had a significantly longer time to antibiotic optimization when compared to the post-RAIDS group （median （IQR）, 27.6 （10.8-75.8） h vs. 3.1 （0.8-34.3） h, p = 0.03）. The RAIDS protocol resulted in quicker time to antibiotic de-escalation （pre- vs. post-RAIDS; median （IQR）, 27.6 （10.8-134.5） h vs. 4.3 （1.4-32.6） h, p = 0.03）. There were no differences in clinical outcomes such as clinical cure, microbiological cure, and 30-day mortality between pre-RAIDS and post-RAIDS study groups. Patients in the post-RAIDS arm were more likely to receive appropriate empiric and definitive treatment. Implementation of the RAIDS protocol, which was an ASP （antimicrobial stewardship program） initiative, resulted in quicker time to antibiotic de-escalation and overall treatment optimization. RAIDS reduced the unnecessary use of broad-spectrum antimicrobial in this study population.

Prevalence and Associated Risk Factors of Uropathogenic Klebsiella Species in Port Harcourt

Background: Urinary tract infection (UTI) is a severe public health issue that affects a wide range of people around the world with Klebsiella pneumoniae accounting for up to 25% of all urinary tract infections. The higher rate of UTI associated with uropathogenic Klebsiella species has been associated with the emergence of hypervirulent and antibiotic-resistant strains facilitated by the misuse and overuse of antibiotics as well as other sociodemographic and behavioural practices of susceptible individuals. This study was aimed at investigating the prevalence and associated risk factors of uropathogenic Klebsiella species in Port Harcourt, Nigeria. Methodology: The study employed a descriptive cross-sectional study design comprising 300 subjects clinically suspected of having urinary tract infections attending the Rivers State University Medical Centre and the Rivers State University Teaching Hospital between March to August 2022. A standard urine culture procedure was used to ascertain significant bacteriuria after which Klebsiella colonies were isolated and identified using standard bacteriological techniques. The data generated from this study was represented as frequency and percentages, and inferential statistics were carried out using Chi-square with the aid of GraphPad Prism Software Version 9. Statistical significance was defined as a p-value of less than 0.05 at a 95% confidence interval. Result: The prevalence of uropathogenic Klebsiella sp. was 16%, with sex, pregnancy status, and religion of the individuals substantially linked (p p Klebsiella species. Conclusion: This study reports a relatively high prevalence of uropathogenic Klebsiella species at 16%, with the sex and pregnancy status of the subjects being significantly associated (p Klebsiella species in the current study. Health promotion and awareness efforts should be prioritised to inform susceptible demographics about their risks for urinary tract infections associated with uropathogenic Klebsiella species via targeted educational campaigns, collaboration with healthcare providers, use of social media and online platforms, workplace wellness programs, and community outreach programs amongst others. Antimicrobial susceptibility testing before prescriptions and treatment should be emphasized and upheld in all clinical settings.

Prevalence of Uropathogenic Escherichia coli among Adult Male Patients 40 Years and above with Haematuria and Impaired Kidney Attending General Hospitals in Benue State

Haematuria is the presence of red blood cells in urine. It is most often caused by urinary tract infections of which Escherichia coli is frequently implicated. Impairment of kidney functions could occur as a result of infection or other complications of the kidney. The aim of the study was to determine the prevalence of uropathogenic Escherichia coli among adult male patients with haematuria and impaired kidneys attending a general hospital in Benue state. Three hundred and sixty-eight (368) samples of urine were collected from 368 male patients (≥ 40 years) attending the 23 general hospitals in Benue state. Each of the urine samples was divided into two parts for haematuria and isolation and identification of Escherichia coli. Blood samples (368) were also collected from the patients and used for quantitative determination of creatinine and estimation of glomerular filtration rate. The presence of haematuria was 45.1% and ranges from 12.5% to 100%. Prevalence of haematuria with respect to age shows that patients within the age group of 90 - 99 years had the highest rate (100%) and the least were those within the ages of 40 - 49 years (20.0%). Isolation rate of uropathogenic Escherichia coli was 16.3% and ranged from 6.3 to 37.5%. Patients within the age group of 90 - 99 years had the highest elevated impaired renal function of 4 (80%), followed by patients within the ages of 80 - 89 years [17 (77.3%)] and the lowest were those within the ages of 40 - 49 [6 (10.0%)]. The overall presence of haematuria in the patients was high (45.1%) with similar high Escherichia coli isolation rate and impaired renal function which could mean that acute or chronic kidney disease may set in.

Comparison of the serum contents of inflammatory mediators and oxidative stress mediators between patients with gram-positive bacteria and gram-negative bacteria infection

Objective: To compare the serum contents of inflammatory mediators and oxidative stress mediators between patients with gram-positive bacteria and gram-negative bacteria infection. Methods: Patients who were diagnosed with bloodstream bacterial infection in Zigong Third People's Hospital between March 2015 and April 2017 were selected as the research subjects and divided into gram-positive group and gram-negative group according to the results of blood culture and strain identification, and serum levels of inflammatory mediators PCT, IL-1β, IL-6, sTREM-1, TNF-α, NGAL, SAA, HPT and hs-CRP as well as oxidative stress mediators MDA, AOPP, TAC, CAT and SOD were determined. Results: Serum PCT, IL-1β, IL-6, sTREM-1, TNF-α, NGAL, SAA, HPT, hs-CRP, MDA and AOPP levels of gram-negative group were greatly higher than those of gram-positive group while TAC, CAT and SOD levels were greatly lower than those of gram-positive group. Conclusion: The changes of inflammatory mediators and oxidative stress mediators in the serum of patients with gram-negative bacteria infection are more significant than those of patients with gram-positive bacteria infection.

尿路感染细胞实验中庆大霉素对尿路致病大肠杆菌的杀伤作用及细胞毒性研究

目的在尿路感染体外细胞实验中,比较不同浓度庆大霉素(0、10、20、50、100、200μg/mL)对尿路致病大肠杆菌(UPEC)的杀伤作用,对尿路上皮细胞及炎性细胞如巨噬细胞的毒性作用。方法比较不同浓度庆大霉素对不同量UPEC J96菌株(10^(8)、10^(7)、10^(6))的杀伤情况;CCK-8实验检测不同浓度庆大霉素在不同时间内(2 h或24 h)对原代培养的C57BL/6雄鼠肾小管上皮细胞、腹腔巨噬细胞、人膀胱上皮细胞系J82的毒性作用;根据实验选择合适的庆大霉素浓度和作用时间,检测J96对小鼠肾小管上皮细胞的黏附、入侵以及小鼠巨噬细胞对J96的吞噬、清除作用。结果庆大霉素(≥10μg/mL)对J96的杀伤作用均强于1%的青霉素/链霉素双抗(P<0.0001),高浓度庆大霉素(≥100μg/mL)可在30 min内完全杀伤高达10^(8)的J96。50μg/mL庆大霉素作用2 h可对人膀胱上皮细胞系J82产生毒性作用(P<0.05)。结论本文明确了不同细胞体外实验时适宜的庆大霉素处理浓度及时间,人膀胱上皮细胞系J82对庆大霉素更为敏感。

Epidemiologic Profile Urinary Tract Infections: Experience of the Microbiology Laboratory of the University Hospital Mohamed VI in Tangier

Urinary tract infection is one of the most common bacterial infections in humans. The urine cytobacteriological examination is the key test for its diagnosis. This work aims to Evaluate the prevalence of urinary tract infection at the Microbiology Laboratory of the University Hospital Mohamed VI in Tangier and to highlight its epidemiological and bacteriological characteristics. It was a descriptive study with retrospective data collection which took place from January 2021 to June 2022, at the Microbiology Laboratory of the university hospital Mohamed VI in Tangier. It covered all urine cytobacteriological examinations (ECBU) during the study period. We identified 77 cases of urinary tract infections out of 300 requests for (ECBU), that is a positivity rate of 25 %. The mean age was 55 years. The male gender was predominant. The epidemiological profile of the isolated strains was dominated by Enterobacteriaceae 81 %, followed by Gram-positive cocci 11 % and non-fermenting gram-negative bacteria 8 %. The main bacteria responsible for urinary tract infections in order of frequency: Escherichia coli 42 %, Klebsiella pneumoniae 20 %, Enterobacter cloacae 9 %, Staphylococcus aureus 6 %, Pseudomonas aeruginosa 5 % and Acinetobacter baumannii 3%. Most of the analyzed organisms showed resistance, especially to the beta-lactam antibiotic;the enterobacteria strains isolated had revealed resistance to amoxicillin: 74%, to amoxicillin-clavulanic acid in 40% of cases, and to third-generation cephalosporins in 24%. In terms of resistance mechanisms, 11 % of the Enterobacteriaceae were extended-spectrum β-lactamase producers and 9 % of the specimens were identified as carbapenemase producers. Of the Staphylococcus aureus strains isolated, 75% were resistant to meticillin. The Glycopeptides and linezolid were the most active molecules on these isolated strains. 15% of Enterococcus species isolated in our laboratory were resistant to glycopeptides (vancomycin and teicoplanin).