Antibiotic Resistance and Virulence Phenotypes of Recent Bacterial Strains Isolated from Urinary Tract Infections in Elderly Patients with Prostatic Disease

Microbial communities, antibiotic resistance genes, and virulence factors in urinary infectious stone-associated urinary tract infections

Urinary infectious stones are challenging due to bacterial involvement, necessitating a comprehensive understanding of these conditions. Antibiotic-resistant urease-producing bacteria further complicate clinical management. In this study, analysis of urine and stone samples from urinary tract infection (UTI) patients revealed microbial shifts, gene enrichment in stones, and metabolic pathway disparities; antibiotic resistance gene trends were phylum-specific, urease-producing bacteria are at risk of acquiring AMR carried by Enterobacteriaceae under antibiotic, emphasizing potential AMR dissemination between them; Correlations of key pathogenic species in kidney stone and urine microbial communities highlight the need for targeted therapeutic strategies to manage complexities in UTIs; Stones and urine contain a variety of deleterious genes even before antibiotic use, and piperacillin/tazobactam better reduced the abundance of antibiotic resistance genes in stones and urine. The presence of diverse antibiotic resistance and virulence genes underscores challenges in clinical management and emphasizes the need for effective treatment strategies to mitigate risks associated with UTIs and urinary infectious stone formation. Ongoing research is vital for advancing knowledge and developing innovative approaches to address these urological conditions.

Enterobacter cloacae from urinary tract infections: frequency, protein analysis, and antimicrobial resistance

The genus Enterobacter belongs to the ESKAPE group, which includes Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp. This group is characterized by the development of resistance to various antibiotics. In recent years, Enterobacter cloacae (E. cloacae) has emerged as a clinically important pathogen responsible for a wide range of healthcare-associated illnesses. Identifying Enterobacter species can be challenging due to their similar phenotypic characteristics. The emergence of multidrug-resistant E. cloacae is also a significant problem in healthcare settings. Therefore, our study aimed to identify and differentiate E. cloacae using Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) as a fast and precise proteomic analytical technique. We also tested hospital-acquired E. cloacae isolates that produce Extended-spectrum beta-lactamases (ESBL) against commonly used antibiotics for treating urinary tract infections (UTIs). We used a total of 189 E. cloacae isolates from 2300 urine samples of patients with UTIs in our investigation. We employed culturing techniques, as well as the BD Phoenix™ automated identification system (Becton, Dickinson) and Analytical Profile Index (API) system for the biochemical identification of E. cloacae isolates. We used the MALDI Biotyper (MBT) device for peptide mass fingerprinting analysis of all isolates. We utilized the single peak intensities and Principal Component Analysis (PCA) created by MBT Compass software to discriminate and cluster the E. cloacae isolates. Additionally, we evaluated the sensitivity and resistance of ESBL-E. cloacae isolates using the Kirby Bauer method. Out of the 189 E. cloacae isolates, the BD Phoenix system correctly identified 180 (95.24%) isolates, while the API system correctly identified 165 (87.30%) isolates. However, the MBT accurately identified 185 (98.95%) isolates with a score of 2.00 or higher. PCA positively discriminated the identified E. cloacae isolates into one group, and prominent peaks were noticed between 4230 mass-to-charge ratio (m/z) and 8500 m/z. The ESBL-E. cloacae isolates exhibited a higher degree of resistance to ampicillin, amoxicillin-clavulanate, cephalothin, cefuroxime, and cefoxitin. Several isolates were susceptible to carbapenems (meropenem, imipenem, and ertapenem); however, potential future resistance against carbapenems should be taken into consideration. In conclusion, MALDI-TOF MS is a powerful and precise technology that can be routinely used to recognize and differentiate various pathogens in clinical samples. Additionally, the growing antimicrobial resistance of this bacterium may pose a significant risk to human health.

Distribution and Drug Resistance of Bacterial Infection in Hospitalized Patients at the Respiratory Department before and after the COVID-19 Pandemic in Guangzhou, China

Since COVID-19 might have a lasting impact on global public health, it is crucial to analyze its effect on drug-resistant bacterial infections in the respiratory system for the prevention and control of hospital infections. This work aimed to investigate the impact of the COVID-19 outbreak on the clinical distribution and antibiotic resistance of bacterial infection among hospitalized patients in the respiratory unit in order to establish strategies to control antibiotic-resistant infections. Electronic clinical data registry records from 2018 to 2022 were retrospectively analyzed. A total of 36,829 clinical specimens, including sputum, bronchoalveolar lavage fluid, blood, and urine, were collected from 16,073 patients admitted to the Guangzhou First People's Hospital from January 2018 to December 2022. Among them, 2209 samples were culture-positive. The bacterial isolation rates of different types of samples showed a similar trend from 2019 to 2022, with an increase in 2020 and 2022 and a decrease in 2021. Different bacterial species were separated from different types of samples. The most reported pathogens were identified in sputum samples. Gram-positive isolates were prevalent in urine samples, while Gram-negative bacilli were the predominant pathogenic bacteria isolated from respiratory tract and blood samples. Pseudomonas aeruginosa (P. aeruginosa), Acinetobacter baumannii (A. baumannii) complex, and Klebsiella pneumoniae (K. pneumoniae) were the most abundant Gram-negative bacteria in sputum samples, of which A. baumannii complex had the highest resistance to all tested antibiotics except colistin. Notably, there has been a substantial prevalence of carbapenem-resistant P. aeruginosa, A. baumannii, and K. pneumoniae in the past five years. This alarming situation calls for greater attention and precaution with prescribed antibiotics to limit the generation and spread of new multidrug-resistant bacteria and improve therapeutic management.

Evaluation of Different Activity of Lactobacillus spp. against Two Proteus mirabilis Isolated Clinical Strains in Different Anatomical Sites In Vitro: An Explorative Study to Improve the Therapeutic Approach

Urinary tract infections (UTIs) and catheter-associated UTIs (CAUTIs) are the principal hospital-acquired infections. Between these, bacterial prostatitis is believed to be the leading cause of recurrent UTIs in men under 50 years of age and is often unresponsive to antibiotic treatment. Proteus mirabilis is more commonly associated with UTIs in these abnormalities, especially in patients undergoing catheterization. Lactobacillus spp. are an important component of the human microbiota and occur in large quantities in foods. Probiotics are proposed as an alternative to antibiotic therapy in the treatment of urinary tract infections. In addition to their ability to produce antimicrobial metabolites, they have immunomodulatory activity and do not cause side effects. For this reason, the combination of probiotic microorganisms and conventional drugs was considered. The aim of this work was to select the most active Lactobacillus strains against two clinical isolates of P. mirabilis on bladder and prostatic epithelium, potentially exploitable to improve the clinical management of UTIs.

Natural Polyphenols for Prevention and Treatment of Urinary Tract Infections

Urinary tract infections (UTIs) are the second most common type of bacterial infection worldwide. UTIs are gender-specific diseases, with a higher incidence in women. This type of infection could occur in the upper part of the urogenital tract, leading to pyelonephritis and kidney infections, or in the lower part of the urinary tract, leading to less serious pathologies, mainly cystitis and urethritis. The most common etiological agent is uropathogenic E. coli (UPEC), followed by Pseudomonas aeruginosa and Proteus mirabilis. Conventional therapeutic treatment involves the use of antimicrobial agents, but due to the dramatic increase in antimicrobial resistance (AMR), this strategy has partially lost its therapeutic efficacy. For this reason, the search for natural alternatives for UTI treatment represents a current research topic. Therefore, this review summarized the results of in vitro and animal- or human-based in vivo studies aimed to assess the potential therapeutic anti-UTI effects of natural polyphenol-based nutraceuticals and foods. In particular, the main in vitro studies were reported, describing the principal molecular therapeutic targets and the mechanism of action of the different polyphenols studied. Furthermore, the results of the most relevant clinical trials for the treatment of urinary tract health were described. Future research is needed to confirm and validate the potential of polyphenols in the clinical prophylaxis of UTIs.

Molecular Characterization of Enterobacter cloacae Isolated from Urinary Tract Infections

Background: Urinary tract infections represent a major expensive, common public health problem worldwide due to their high prevalence and the difficulties associated with their management. Objectives: This study aimed to characterize the Enterobacter cloacae strains isolated from urinary tract infections in the medical diagnostic laboratories of Shahrekord, Iran. Methods: Urine samples from patients with urinary tract infections from the Shahrekord medical diagnostic laboratories located in Chaharmahal and Bakhtiari Province, Iran, were collected from June 2019 to February 2020. When the samples were cultured, the different isolates of E. cloacae were identified by biochemical tests. Biofilm production capacity was evaluated. Bacterial susceptibility to antibiotics was determined using the Kirby Bauer method, and antibiotic resistance genes were researched by the multiplex PCR technique. Results: In this study, 65 isolates of E. cloacae were obtained. The highest percentage of resistance was observed for co-trimoxazole (84.62%), ampicillin (76.93%), tetracycline (73.85%), and above half of the E. cloacae strain isolates (53,85%) were strongly involved in biofilm production. Some genes, including qnr A, qnr B, qnr S, tetA, tet B, sul1, bla CTXM, bla SHV, and(2)la, ant(3)la, and aac(3)IIa, were detected in the genome of these isolates. Conclusions: The strains are multi-resistant, and their resistance has already reached the carbapenem class. This requires further investigation, and urgent measures must be adopted.

What Doesn’t Kill Them Makes Them Stronger: The Impact of the Resistance Patterns of Urinary Enterobacterales Isolates in Patients from a Tertiary Hospital in Eastern Europe

(1) Background: The evolution of bacterial resistance to antibiotics is one of the factors that make infectious pathology an extremely dynamic field, also inducing a significant burden on public health systems; therefore, continuous updates on the bacterial resistance to antibiotics and their particular regional patterns is crucial for the adequate approach of various infectious diseases. (2) Methods: We retrospectively analyzed 354 patients with Enterobacterales urinary tract infections (UTIs), determined their antibiotic resistance pattern, thus aiming to correlate them with the outcome and other specific markers of poor prognosis. (3) Results: The most frequent causative agent was Escherichia coli, representing 64.6% of all UTIs. We identified 154 patients resistant to multiple antibiotic classes, of which 126 were multidrug-resistant (MDR), 17 were extensive drug-resistant (XDR) and 11 were pandrug-resistant (PDR). Moreover, 25 isolates were resistant to carbapenems (CRE), 25 were difficult-to-treat (DTR), and 84 were extended-spectrum cephalosporin-resistant (ESC), with only 95 isolates susceptible to all tested antibiotics. Mortality ranged from 1% for UTIs caused by isolates susceptible to all tested antibiotics, to 24% for the ones caused by DTR or CRE isolates. Other significant risk factors associated with mortality were: prolonged hospital stay (p = 0.0001), Charlson comorbidity index ≥ 3 (p = 0.02), urinary catheterization (p = 0.001), associated respiratory pathologies (p = 0.004), obesity (p = 0.047), a history of previous hospitalizations (p = 0.007), inappropriate empiric antibiotic regimen (p = 0.001), or hyper inflammatory status (p = 0.006). Basically, we observed that a multiple regression model comprising urinary catheterization, inappropriate empiric anti-biotherapy, obesity, and respiratory comorbidities exhibits the best correlation with mortality rate in patients with UTI (R = 0.347, R² = 0.12). (4) Conclusions: By focusing on the novel resistance patterns, our study provides complementary evidence concerning the resistance profiles found in an Eastern European region, as well as their prognostic implications in patients with UTI.

Phenolic Content and Antimicrobial and Anti-Inflammatory Effects of Solidago virga-aurea, Phyllanthus niruri, Epilobium angustifolium, Peumus boldus, and Ononis spinosa Extracts

Prostatitis is an inflammatory condition that is related to multiple infectious agents, including bacteria and fungi. Traditional herbal extracts proved efficacious in controlling clinical symptoms associated with prostatitis. In this context, the aim of the present study was to explore the efficacy of extracts from Solidago virga-aurea, Ononis spinosa, Peumus boldus, Epilobium angustifolium, and Phyllanthus niruri against bacterial (Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus cereus) and fungi strains (Candida albicans; C. tropicalis) involved in prostatitis. Additionally, anti-mycotic effects were tested against multiple species of dermatophytes (Trichophyton rubrum, T. tonsurans, T. erinacei, Arthroderma crocatum, A. quadrifidum, A. gypseum, A. currey, and A. insingulare). Antioxidant effects were also evaluated in isolated rat prostates challenged with lipopolysaccharide (LPS), and phytochemical analyses were conducted to identify and quantify selected phenolic compounds, in the extracts. Finally, a bioinformatics analysis was conducted to predict putative human and microbial enzymes targeted by extracts’ phytocompounds and underlying the observed bio-pharmacological effects. The phytochemical analysis highlighted that rutin levels could be crucial for explaining the highest antibacterial activity of P. boldus extract, especially against E. coli and B. cereus. On the other hand, in the E. angustifolium extract, catechin concentration could partially explain the highest efficacy of this extract in reducing lipid peroxidation, in isolated rat prostates stimulated with LPS. Concluding, the results of the present study showed moderate antimicrobial and anti-inflammatory effects induced by water extracts of S. virga-aurea, P. boldus, E. angustifolium, P. niruri, and O. spinosa that could be related, at least partially, to the phenolic composition of the phytocomplex.

Screening for chronic prostatitis pathogens using high-throughput next-generation sequencing

BACKGROUND

The pathogens responsible for chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS; NIH category III) are not currently known. the present study utilized high-throughput next-generation sequencing to screen for potential pathogens associated with NIH category III CP (CP III).

METHODS

This study included 33 patients with CP III and 30 healthy men, from which one sample each of urethral secretions and expressed prostatic secretion (EPS) was collected. High-throughput next-generation sequencing was performed to detect the sequence variations and the relative abundance of the bacterial 16S ribosomal variable region and fungal internal transcribed spacer region in all samples. Bioinformatics software and databases were used for data analysis, and differences with P < .05 were considered statistically significant.

RESULTS

Unweighted pair group method with arithmetic mean (UPGMA) cluster analysis, principal component analysis (PCA), and Spearman's rank correlation showed that the microbial compositions of the urethral secretions and EPS collected from the same subject were essentially the same.

CONCLUSIONS

No potential pathogens were identified in diagnosed patients with CP III. The EPS may be free from bacteria before and after infection. Changes in the urinary tract microbiome may disrupt the microecological balance of the urinary system, thereby leading to CP III. Conversely, the true pathogens of CP III may not be prokaryotic or eukaryotic microorganisms, Future research may involve the evaluation of noncellular microbes.

Comparative Analysis of Virulence Profiles of Serratia marcescens Isolated from Diverse Clinical Origins in Mexican Patients

Background: Serratia marcescens is an enteric bacterium with increasing incidence in clinical settings, attributed mainly to the opportune expression of diverse virulence determinants plus a wide intrinsic and acquired antibiotic resistance. Methods: The aim of this study was to compare the virulence factor profiles of 185 Serratia marcescens isolates from different clinical origins. In vitro proteolytic and hemolytic activities, biofilm formation, and motility were assessed in each strain. Additionally, the pathogenicity of four hypervirulent strains was analyzed in vivo in Galleria mellonella. Results: We found that bacterial isolates from wound/abscess and respiratory tract specimens exhibited the highest protease activity along with a strong biofilm production, while uropathogenic isolates showed the highest hemolytic activity. Swarming and swimming motilities were similar among all the strains. However, respiratory tract isolates showed the most efficient motility. Two hyperhemolytic and two hyperproteolytic strains were detected; the latter were more efficient killing Galleria mellonella with a 50%-60% larval mortality 48 hours after challenge. Conclusion: A correlation was found between biofilm formation and proteolytic and hemolytic activities in biopsy specimens and bloodstream isolates, respectively. Overall, it becomes critical to evaluate and compare the clinical strains virulence diversity in order to understand the underlying mechanisms that allow the establishment and persistence of opportunistic bacterial infections in the host.

The Microbiome of Prostate Fluid Is Associated With Prostate Cancer

Objectives

To explore the microbiome of the prostatic fluid in high prostate-specific antigen (PSA) patients.

Patients and Methods

The microbiome profiles of prostatic fluid samples from 32 prostate cancer (PCa) patients and 27 non-PCa people were assessed. Microbiome analysis was assessed by massive 16S ribosomal RNA gene sequencing.

Results

Compared with the NCA group, the microbial diversity was lower in the CA group. There were no specific microbial species in the CA group or NCA group. However, many species, such as those in the genera Alkaliphilus, Enterobacter, Lactococcus, Cronobacter, Carnobacterium, and Streptococcus, showed a significant difference between the CA group and NCA group.

Conclusion

The prostate contains reduced bacteria, suggesting a possible pathophysiological correlation between the composition of the microbiome and PCa. Meanwhile, this study uncovered that the microbiome may be beneficial in maintaining the stability of the microenvironment of the prostate and provides interesting perspectives for the identification of novel biomarkers in high-PSA patients.

Induction of Different Apoptosis Pathways by Two Proteus mirabilis Clinical Isolates Strains in Prostatic Epithelial Cells

Bacterial prostatitis is believed to be the leading cause of recurrent urinary tract infections (UTIs) in men under 50 years of age and occurs both as an acute febrile disease responsive to antibiotics and as a chronic infection that is often unresponsive to antibiotic treatment. Proteusmirabilis is more commonly associated with UTIs in these abnormalities, especially in patients undergoing catheterisation. This pathogen is able to colonise the host’s tissues and to cause disease thanks to the production of many virulence factors such as fimbriae, flagella, immune avoidance, host-damaging factors, and the ability to form crystalline biofilms. In addition, Proteus lipid A may exhibit apoptotic activity and induce desquamation of epithelial cells. The aim of this work was to evaluate the ability of two clinically isolated strains of P. mirabilis that are phenotypically different, named PM1 of PM2, respectively, to induce apoptosis in human prostatic adenocarcinoma PC-3. Our results demonstrate that PM1 and PM2 are able to activate two different apoptotic pathways, and this different behaviour is confirmed by the expression level of the ZapA gene, molecular fingerprinting and different spectrum of antibiotic resistance. The identification and knowledge of relations between the microorganism and host may provide the basis for new solutions to clinical problems with regard to diagnosis and therapy.

Antimicrobial Resistance of Uropathogenic Escherichia coli from Elderly Patients at a General Hospital, Argentina

Background:

Urinary Tract Infection (UTI) is a common cause of morbidity and mortality in older adults.

Objective:

To investigate antimicrobial resistance of uropathogenicEscherichia colifrom elderly patients in a General Hospital, Argentina.

Method:

During the period July 2011-July 2015, patients over 70 years old with urinary tract infections, without urinary catheters and with no antimicrobial therapy the previous week before sampling, were included. Phenotypic characterization was carried out.In vitroqualitative and quantitative antimicrobial resistances were investigated. Antimicrobials assayed: ampicillin, amoxicillin-clavulanate, cefazolin, cefuroxime, cefoxitin, cefotaxime, ceftazidime, cefepime, imipenem, ertapenem, gentamicin, nalidixic acid, ciprofloxacin, trimethoprim-sulfamethoxazole (TMS) and nitrofurantoin. Patients’ medical records were produced, and risk factors were analyzed by multivariate analysis.

Results:

768 bacterial isolates were identified asE. coli. Resistances to ampicillin (80.5%), nalidixic acid (61.7%), ciprofloxacin (42.8%), TMS (37.6%), amoxicillin-clavulanate (28.6%), cefazolin (21.6%), cefuroxime (20.7%), gentamicin (13.8%), cefotaxime (9.7%), ceftazidime (9.7%), cefepime (8.4%), cefoxitin (3.1%) and nitrofurantoin (2.3%) were observed. Resistance to carbapenems was not expressed. Production of extended spectrum β-lactamases was detected (7.6%) in community acquired (96%) and healthcare associated (4%) isolates. The independent risk factors for urinary infections produced by multi-resistantE. coliwere: diabetes mellitus, recurrent infections, hospitalization during the last year and exposure to β-lactams in the last 3 months.

Conclusion:

A high prevalence of resistance to β-lactams and to other antimicrobials was observed. Detection of antimicrobial multi-resistant isolates highlights the need of antimicrobial resistance surveillance in elderly patients with urinary tract infections.

Phylogenetic relationships, biofilm formation, motility, antibiotic resistance and extended virulence genotypes among Escherichia coli strains from women with community-onset primitive acute pyelonephritis

The present work set out to search for a virulence repertoire distinctive for Escherichia coli causing primitive acute pyelonephritis (APN). To this end, the virulence potential of 18 E. coli APN strains was genotypically and phenotypically assessed, comparatively with 19 strains causing recurrent cystitis (RC), and 16 clinically not significant (control, CO) strains. Most of the strains belong to phylogenetic group B1 (69.8%; p<0.01), and APN strains showed unique features, which are the presence of phylogroup A, and the absence of phylogroup B2 and non-typeable strains. Overall, the most dominant virulence factor genes (VFGs) were ecpA and fyuA (92.4 and 86.7%, respectively; p<0.05), and the mean number of VFGs was significantly higher in uropathogenic strains. Particularly, papAH and malX were exclusive for uropathogenic strains. APN and RC strains showed a significantly higher prevalence of fyuA, usp, and malX than of CO strains. Compared to RC strains, APN ones showed a higher prevalence of iha, but a lower prevalence of iroN, cnf1, and kpsMT-II. Hierarchical cluster analysis showed a higher proportion of two gene clusters (malX and usp, and fyuA and ecpA) were detected in the APN and RC groups than in CO, whereas iutA and iha clusters were detected more frequently in APN strains. The motility level did not differ among the study-groups and phylogroups considered, although a higher proportion of swarming strains was observed in APN strains. Antibiotic-resistance rates were generally low except for ampicillin (37.7%), and were not associated with specific study- or phylogenetic groups. APN and RC strains produced more biofilm than CO strains. In APN strains, iha was associated with higher biofilm biomass formation, whereas iroN and KpSMT-K1 were associated with a lower amount of biofilm biomass. Further work is needed to grasp the virulence and fitness mechanisms adopted by E. coli causing APN, and hence develop new therapeutic and prophylactic approaches.