Comparative Epidemiology and Resistance Trends of Common Urinary Pathogens in a Tertiary-Care Hospital: A 10-Year Surveillance Study

Novel BRICHOS-Related Antimicrobial Peptides from the Marine Worm Heteromastus filiformis: Transcriptome Mining, Synthesis, Biological Activities, and Therapeutic Potential

Marine polychaetes represent an extremely rich and underexplored source of novel families of antimicrobial peptides (AMPs). The rapid development of next generation sequencing technologies and modern bioinformatics approaches allows us to apply them for characterization of AMP-derived genes and the identification of encoded immune-related peptides with the aid of genome and transcriptome mining. Here, we describe a universal bioinformatic approach based on the conserved BRICHOS domain as a search query for the identification of novel structurally unique AMP families in annelids. In this paper, we report the discovery of 13 novel BRICHOS-related peptides, ranging from 18 to 91 amino acid residues in length, in the cosmopolitan marine worm Heteromastus filiformis with the assistance of transcriptome mining. Two characteristic peptides with a low homology in relation to known AMPs-the α-helical amphiphilic linear peptide, consisting of 28 amino acid residues and designated as HfBRI-28, and the 25-mer β-hairpin peptide, specified as HfBRI-25 and having a unique structure stabilized by two disulfide bonds-were obtained and analyzed as potential antimicrobials. Interestingly, both peptides showed the ability to kill bacteria via membrane damage, but mechanisms of their action and spectra of their activity differed significantly. Being non-cytotoxic towards mammalian cells and stable to proteolysis in the blood serum, HfBRI-25 was selected for further in vivo studies in a lethal murine model of the Escherichia coli infection, where the peptide contributed to the 100% survival rate in animals. A high activity against uropathogenic strains of E. coli (UPEC) as well as a strong ability to kill bacteria within biofilms allow us to consider the novel peptide HfBRI-25 as a promising candidate for the clinical therapy of urinary tract infections (UTI) associated with UPEC.

Frequency of Urinary Tract Infection Among Patients Undergoing Implant Fixation for Acute Trauma

OBJECTIVE

This study aims to determine the frequency of urinary tract infection (UTI), identify the isolated bacteria, and assess antibiotic sensitivity in patients undergoing orthopedic implant fixation for hip fractures.

METHODOLOGY

After ethical approval from the institutional review board, this retrospective cross-sectional study was conducted at the Orthopedic Surgery Department of Dow University Hospital Karachi from June 2022 to June 2023. Through non-probability consecutive sampling, 186 patients above 16 years of age, of either gender, presenting with hip fractures such as intracapsular or extracapsular fractures, who underwent surgical fixation, were included in the study. A urine sample for urinalysis of these patients was sent on admission. Patients who presented with open fractures or those treated with conservative management were excluded from the study. The fracture diagnosis was confirmed on radiographs. All other relevant baseline investigations were also performed before surgery, per protocol, and urine-detailed and cultured reports were followed. In addition, each patient was asked about common symptoms of UTI before surgery and then diagnosed with UTI on positive urine culture and sensitivity (CS).

RESULTS

Out of 186 hip fracture patients, 98 (52.7%) were males and 88 (47.3%) were females, with a mean age of 61.03 ± 16.43 (16-96) years. Pre-operative UTI symptoms were reported by 79 patients, including dysuria (16; 20.3%), polyuria (19; 24.0%), and burning (44; 55.7%). UTI was diagnosed on culture and sensitivity report in 65 (34.9%) patients with Escherichia coli as commonly diagnosed bacteria 35 (53.8%), followed by Enterococcus 8 (12.4%), Klebsiella 7 (10.9%), Pseudomonas aeruginosa 3 (4.7%), and Acinetobacter 2 (3.1%) patients. E. coli was sensitive to amikacin, amoxicillin/clavulanic acid, ampicillin, cefixime, ceftriaxone, cefuroxime, ciprofloxacin, colistin, cotrimoxazole, fosfomycin, gentamycin, levofloxacin, meropenem, nitrofurantoin, polymyxin B, and piperacillin-tazobactam.

CONCLUSION

Urinary tract infection is common in patients undergoing orthopedic implant fixation for hip fractures, which can lead to potentially serious outcomes. Overall, hygiene, prompt treatment, and standard protocol should be utilized to treat those infected and minimize the spread.

Analysis of Cumulative Antibiogram Reports in Search for Optimal Empirical Urinary Tract Infection Treatment at the Central Teaching Hospital of the Medical University of Lodz, Poland: Results of a 3-Year Surveillance

Urinary tract infections are among the most common bacterial infections, accounting for about two-fifths of all healthcare-associated infections. Appropriate antimicrobial therapy is crucial, e.g., to avoid prolonged hospitalization and limit antimicrobial resistance spread. This study was performed to analyze the microbiological profiles of urinary tract infections in the Central Teaching Hospital in Lodz, Poland, and develop local empirical therapy guidelines. This study was a 3-year retrospective surveillance of the cumulative antibiograms from urine cultures. The procedures were based on the current EUCAST and CLSI guidelines. In 2020-2022, a total of 4656 urine cultures were performed, of which 1134 were positive. The most common bacterial isolates were Escherichia coli, followed by Klebsiella spp. and Enterococcus spp. High levels of susceptibility (>90%) have been observed for carbapenems, piperacillin/tazobactam, amikacin, and nitrofurantoin. Development of the appropriate empirical antimicrobial is a challenging task with persistently high levels of resistance to commonly used antimicrobials. Eventually, we separated the uncomplicated and complicated urinary tract infections in local guidelines and recommended nitrofurantoin and amikacin, respectively, in empiric therapy. The clinicians should make a decision based on the presented symptoms and then-with the urine culture result-correct or continue the therapy.

Antibiotic Resistance Profiling of Pathogenic Staphylococcus Species from Urinary Tract Infection Patients in Benin

Staphylococci can cause urinary tract infections (UTIs). These UTIs are among the significant causes of antibiotic resistance and the spread of antibiotic-resistant diseases. The current study is aimed at establishing a resistance profile and determining the pathogenicity of Staphylococcus strains isolated from UTI samples collected in Benin. For this purpose, urine samples (one hundred and seventy) that were collected from clinics and hospitals showed UTI in patients admitted/visited in Benin. The biochemical assay method was used to identify Staphylococcus spp., and the disk diffusion method tested the antimicrobial susceptibility. The biofilm formation ability of the isolates of Staphylococcus spp. was investigated by the colorimetric method. The presence of mecA, edinB, edinC, cna, bbp, and ebp genes was examined by multiplex polymerase chain reaction (PCR). The results showed that Staphylococcus species were identified in 15.29% of all infected individuals and that 58% of these strains formed biofilms. Most Staphylococcus strains (80.76%) were isolated in female samples, and the age group below 30 years appeared to be the most affected, with a rate of 50%. All Staphylococcus strains isolated were 100% resistant to penicillin and oxacillin. The lowest resistance rates were seen with ciprofloxacin (30.8%), gentamicin, and amikacin (26.90%). Amikacin was the best antibiotic against Staphylococcus strains isolated from UTIs. The isolates carried mecA (42.31%), bbp (19.23%), and ebp (26.92%) genes in varying proportions. This study provides new information on the risks posed to the population by the overuse of antibiotics. In addition, it will play an essential role in restoring people's public health and controlling the spread of antibiotic resistance in urinary tract infections in Benin.

A 2-Year Audit on Antibiotic Resistance Patterns from a Urology Department in Greece

PURPOSE

The high incidence of urinary tract infections (UTIs), often in nosocomial environments, is a major cause of antimicrobial resistance (AMR). The dissemination of antibiotic-resistant infections results in very high health and economic burdens for patients and healthcare systems, respectively. This study aims to determine and present the antibiotic resistance profiles of the most common pathogens in a urology department in Greece.

METHODS

During the period 2019-2020, we included 12,215 clinical samples of blood and urine specimens that tested positive for the following pathogens: Escherichia coli, Enterococcus faecium, Enterococcus faecalis, Proteus mirabilis, Klebsiella pneumoniae, or Pseudomonas aeruginosa, as these are the most commonly encountered microbes in a urology department.

RESULTS

The analysis revealed a 22.30% mean resistance rate of E. coli strains with a 76.42% resistance to ampicillin and a 54.76% resistance rate to ciprofloxacin in the two-year period. It also showed an approximately 19% resistance rate of P. mirabilis strains and a mean resistance rate of 46.205% of K. pneumoniae strains, with a decreasing trend during the four semesters (p-value < 0.001), which presented an 80% resistance rate to ampicillin/sulbactam and 73.33% to ciprofloxacin. The resistance to carbapenems was reported to be 39.82%. The analysis revealed a 24.17% mean resistance rate of P. aeruginosa with a declining rate over the two-year period (p-value < 0.001). The P. aeruginosa strains were 38% resistant to fluoroquinolones and presented varying resistance against carbapenems (31.58% against doripenem and 19.79% against meropenem). Regarding the Enteroccocal strains, a 46.91% mean resistance was noted for E. faecium with 100% resistance to ampicillin, and a 24.247% mean resistance rate for E. faecalis strains that were 41% resistant to ciprofloxacin. Both types showed 100% sensitivity to linezolid.

CONCLUSIONS

The dissemination of antibiotic-resistant pathogens poses the need to implement surveillance programs and, consequently, to develop strategies to prevent the emergence of such pathogens in order to optimize patient outcomes.

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.

Magnitude of Multidrug-resistant Bacterial Uropathogens and Associated Factors in Urinary Tract Infection Suspected Adult HIV-Positive Patients in Southern Ethiopia

Background:

Due to the reduction of their immunity, people living with the human immunodeficiency virus (HIV) are more susceptible to acquiring urinary tract infections (UTI). Moreover, the emergence of drug-resistant bacterial uropathogens has grown widely and now constitutes a severe clinical problem among HIV-positive patients.

Methods:

An institution-based cross-sectional study was conducted at the ART clinic of Arba Minch General Hospital from 1st January to 30th May, 2021. A total of 251 adult HIV-positive patients clinically suspected of having UTIs were systematically recruited. Socio-demographic and other factors were collected by a pre-tested structured questionnaire. A clean-catch mid-stream urine sample was collected and inoculated onto blood agar, MacConkey agar, and cysteine lactose electrolyte deficient agar (CLED). The inoculated culture media were incubated aerobically at 37°C for 24 hrs. After overnight incubation, significant bacteriuria, 105 CFU/ml, was considered. Bacterial identification was made by standard protocols. Antimicrobial susceptibility testing was done by Kirby Bauer’s disk diffusion method. The data was analyzed using SPSS version 25. A P-value less than 0.05 was used as statistical significance.

Results:

The overall magnitude of multidrug-resistant (MDR) uropathogens was found to be 14.3%, with a 95% CI (10-19.1). Gram-negative bacteria (83.3%) were the predominant MDR isolates, with E. coli (41.7%) followed by K. pneumoniae (22.2%). All isolates of S. aureus and two-thirds of the isolated CoNS were MDR. A total of 30% and 16.7% of Gram-negative isolates were ESBL and carbapenemase producers, respectively, whereas 50% and 33.3% of isolated S. aureus and CoNS were methicillin-resistant, respectively. Antibiotic use in the previous 6 months [AOR = 6.7, 95% CI: (2.53-17.6)], presence of chronic underlying disease [AOR = 7.03, 95% CI: (1.72-28.73)], antibiotic use without a prescription [AOR = 9.7, 95% CI: (3.53-26.675)], CD4+ counts less than 250 cells/mm3 [AOR = 8.05, 95% CI: (2.078–31.154)], and CD4+ count in between 250-500 cells/mm3 [AOR = 2.49, 95% CI: (1.05-5.923)] were found to be statistically significant associated with MDR uropathogens.

Conclusion:

This study found a significant number of multidrug-resistant uropathogens, indicating that healthcare providers should be aware of this and take urgent action to minimize resistance spread, as well as consider current empirical antibiotic therapy for UTI in HIV-positive patients.

Electro-fulguration for extensive inflammatory bladder lesions in post-menopausal women with antibiotic-recalcitrant recurrent urinary tract infections

INTRODUCTION AND HYPOTHESIS

To evaluate how women with uncomplicated antibiotic-recalcitrant recurrent urinary tract infections (RUTIs) and extensive inflammatory bladder lesions on office cystoscopy responded to electro-fulguration (EF) to eliminate these chronic bladder sites.

METHODS

After IRB approval, a retrospective study of non-neurogenic women with RUTIs, inflammatory lesions on cystoscopy, and who underwent EF was performed. Lesions were classified through a simplified staging system based on the extent of bladder wall involvement. Only those with extensive bladder wall involvement (stages 3 and 4) at the time of EF were analyzed in this report. Six months after EF, an office cystoscopy was performed, with endoscopic success defined as no lesions seen. The primary clinical outcome was number of symptomatic UTIs after EF, defined as cure (0/year), improvement (1-2/year), and failure (≥3/year).

RESULTS

From 2007 to 2019, a total of 57 women met the study criteria, 30 stage 3 and 27 stage 4. Nineteen (63%) were endoscopically successful in stage 3 and 11 (41%) in stage 4. Mean follow-up was 2.9 years (stage 3) and 3.1 years (stage 4). All had at least a 6-month UTI follow-up after the 6 months of office cystoscopy, with 15 patients cured, 37 improved, and 5 failed (all stage 4).

CONCLUSIONS

Although EF only resulted in 63% complete endoscopic resolution, the majority experienced a decrease in the frequency of UTIs, suggesting that EF can be durably effective even in women with very extensive cystitis lesions.

Virulence genes, phylogenetic analysis, and antimicrobial resistance of Escherichia coli isolated from urinary tract infection in hospitalized patients and outpatients

Uropathogenic Escherichia coli (UPEC) strains are the most common cause of urinary tract infection (UTI) in hospitalized and community patients. The aim was to compare the genetic characteristics of E. coli isolated from inpatients (IPs) and outpatients (OPs) with UTI regarding their phylogenies, virulence traits, and resistance trends. In this cross-sectional study, 130 epidemiologically unrelated E. coli isolates were collected from patients with UTI. Extended-spectrum beta-lactamase (ESBL) production was detected by the combination disk method. UPEC and intestinal pathogenic E. coli (IPEC) virulence genes were detected by polymerase chain reaction. The isolates were analyzed for phylogenetic grouping. A P value of < 0.05 was considered significant. Of the 130 isolates, 62.3% were from OPs and 37.7% from IPs. About 35.8% of the OPs and 49% of the IPs were ESBL positive. Moreover, 56.8% of the OPs and 59.2% of the IPs were positive for UPEC virulence genes. Notably, 50% of the isolates from each group exhibited IPEC virulence properties. The predominant phylogroup was B2 (43.2% in the OPs and 40.8% in the IPs). No significant difference was found between the IP and OP isolates (P > 0.05). Our results may indicate that consideration should also be given to hygienic standards in the community. The marked genetic plasticity of E. coli has allowed the emergence of strains showing arrays of genes from different pathotypes. Characterization of E. coli isolates in different areas may guide the selection of effective infection control strategies.

Prevalencia de aislamientos de Escherichia coli y Klebsiella pneumoniae productoras de betalactamasas de espectro extendido en pacientes cubanos ambulatorios con infección del tracto urinario

Introducción. Las infecciones del tracto urinario (UTI) adquiridas en la comunidad causadas por enterobacterias productoras de β-lactamasas de espectro extendido (BLEE) son un fenómeno creciente a nivel mundial. Objetivo. Determinar la prevalencia de aislamientos de Escherichia coli y Klebsiella pneumoniae productoras de BLEE obtenidos de muestras de orina de pacientes ambulatorios con ITU adquirida en la comunidad, así como los perfiles de resistencia a antibióticos asociados al fenotipo BLEE. Materiales y métodos. Estudio descriptivo retrospectivo. Se analizaron 304 aislamientos de E. coli y 34 de K. pneumoniae obtenidos de urocultivos de pacientes con ITU adquirida en la comunidad atendidos entre enero 1 de 2019 y diciembre 31 de 2020 en el Hospital Clínico-Quirúrgico Docente Aleida Fernández Chardiet, provincia Mayabeque, Cuba. Se realizó un análisis bivariado (prueba x2) para determinar diferencias en las tasas de resistencia antibiótica entre las bacterias productoras de BLEE y las no productoras. Resultados. El 16.77% (51/304) y el 17.64 % (6/34) de los aislamientos de E. coli y K. pneumoniae se clasificaron como bacterias productoras de BLEE. En el caso de los aislados de E. coli productoras de BLEE, BLEE+ciprofloxacina fue el patrón de resistencia más frecuente (22/51; 43.13%), seguido por BLEE+ciprofloxacino y amikacina (14/51; 27.45%). Además, 41.17% (21/51); fueron multirresistentes. En el caso de K. pneumoniae productoras de BLEE, predominó el patrón de resistencia BLEE + ciprofloxacino, amikacina y nitrofurantoina (2/6; 33.33%), y 50 % (3/6) fueron multirresistentes. Conclusiones. Los resultados confirman la presencia de E. coli y K. pneumoniae productoras de BLEE, con una alta prevalencia de multirresistencia en pacientes con ITU adquirida en la comunidad en el municipio de Güines, Cuba.

To kill or to be killed: pangenome analysis of Escherichia coli strains reveals a tailocin specific for pandemic ST131

BACKGROUND

Escherichia coli (E. coli) has been one of the most studied model organisms in the history of life sciences. Initially thought just to be commensal bacteria, E. coli has shown wide phenotypic diversity including pathogenic isolates with great relevance to public health. Though pangenome analysis has been attempted several times, there is no systematic functional characterization of the E. coli subgroups according to the gene profile.

RESULTS

Systematically scanning for optimal parametrization, we have built the E. coli pangenome from 1324 complete genomes. The pangenome size is estimated to be ~25,000 gene families (GFs). Whereas the core genome diminishes as more genomes are added, the softcore genome (≥95% of strains) is stable with ~3000 GFs regardless of the total number of genomes. Apparently, the softcore genome (with a 92% or 95% generation threshold) can define the genome of a bacterial species listing the critically relevant, evolutionarily most conserved or important classes of GFs. Unsupervised clustering of common E. coli sequence types using the presence/absence GF matrix reveals distinct characteristics of E. coli phylogroups B1, B2, and E. We highlight the bi-lineage nature of B1, the variation of the secretion and of the iron acquisition systems in ST11 (E), and the incorporation of a highly conserved prophage into the genome of ST131 (B2). The tail structure of the prophage is evolutionarily related to R2-pyocin (a tailocin) from Pseudomonas aeruginosa PAO1. We hypothesize that this molecular machinery is highly likely to play an important role in protecting its own colonies; thus, contributing towards the rapid rise of pandemic E. coli ST131.

CONCLUSIONS

This study has explored the optimized pangenome development in E. coli. We provide complete GF lists and the pangenome matrix as supplementary data for further studies. We identified biological characteristics of different E. coli subtypes, specifically for phylogroups B1, B2, and E. We found an operon-like genome region coding for a tailocin specific for ST131 strains. The latter is a potential killer weapon providing pandemic E. coli ST131 with an advantage in inter-bacterial competition and, suggestively, explains their dominance as human pathogen among E. coli strains.

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.

Does the COVID Pandemic Modify the Antibiotic Resistance of Uropathogens in Female Patients? A New Storm?

Urinary tract infections (UTIs) represent a common pathology among female patients, leading to overprescribing antibiotics, globally. The emergence of the COVID-19 pandemic has dramatically increased the incidence of this particular viral pneumonia with secondary bacterial superinfection, resulting in continuous therapeutic or prophylactic recommendations of antibiotic treatment; thus, an updated analysis of current antimicrobial resistance among uropathogens is mandatory. This cross-sectional retrospective study conducted in two university hospitals in Bucharest, Romania analyzed 2469 positive urine cultures, among two different periods of 6 months, before and during the COVID-19 pandemic. The most common pathogen was Escherichia coli 1505 (60.95%), followed by Klebsiella spp. 426 (17.25%). Enterococcus spp. was the leading Gram-positive pathogen 285 (11.54%). In gram negative bacteria, in almost all cases, an increased in resistance was observed, but the highest increase was represented by quinolones in Klebsiella spp., from 16.87% to 35.51% and Pseudomonas from 30.3% to 77.41%; a significant increase in resistance was also observed for carbapenems. Surprisingly, a decrease in resistance to Penicillin was observed in Enterococcus spp., but the overall tendency of increased resistance is also maintained for gram positive pathogens. The lack of data on the influence of the COVID-19 pandemic on uropathogens’ resistance promotes these findings as important for every clinician treating UTIs and for every specialist in the medical field in promoting reasonable recommendations of antibiotic therapies.

Urinary Tract Infections and Associated Factors among Patients with Indwelling Urinary Catheters Attending Bugando Medical Centre a Tertiary Hospital in Northwestern Tanzania

Complications of indwelling urinary catheterization (IUC) are associated with significant morbidity and mortality, thus affecting patient's well-being. Understanding the magnitude and factors associated with complications is crucial in designing appropriate preventive strategies. A cross-sectional study was conducted at Bugando Medical Centre, involving patients with long-term and short-term IUC from December 2016 to September 2017. The data were analyzed by STATA 13.0. Catheter-associated urinary tract infection (CA-UTI) was the leading (56.8%; 250/440) complication among patients with IUC. Gram-negative bacteria were predominantly isolated (98.1%, 252/257), whereas E. coli (30.7%, 79/257) and Klebsiella spp. (29.6%, 76/257) were the leading pathogens. CA-UTI was significantly higher among out-patients than in-patients (82.2% v 35.3%, p < 0.001). Older age (OR: 1.3, (95%CI: 1.1-1.5), p < 0.001), level of education (OR: 1.8, (95%CI: 1.1-3.1), p = 0.029) and catheter duration of ≥6 weeks (OR: 2.43, (95%CI: 1.1-5.5), p = 0.031) independently predicted CA-UTI among outpatients, while female gender (OR: 2.1, (95%CI: 1.2-3.7), p = 0.014), catheter bags not freely hanging (OR: 0.4, (95%CI: 0.2-0.7), p = 0.002) and residing outside Mwanza region (OR: 0.4, (95%CI: 0.2-0.6), p < 0.001) predicted CA-UTI among in-patients. CA-UTI is the common complication among patients with IUC, significantly higher in out-patients than in-patients. We recommend involving patients and carers in infection prevention and control measures in out-patients living with IUC.

Urinary Tract Infection Etiological Profiles and Antibiotic Resistance Patterns Varied Among Different Age Categories: A Retrospective Study From a Tertiary General Hospital During a 12-Year Period

Background

Urinary tract infections (UTIs) are among the most common infections worldwide. With continuing trends of antibiotic resistance, the etiological distribution and antibiotic susceptibility surveillance are of great importance for empirical antimicrobial therapy. The risk factors and clinical circumstances of UTI among different age categories varied; thus, the pathogens and antimicrobial susceptibilities of UTI may also change with age. The aim of this study was to compare the etiological profiles and antibiotic resistance patterns of UTIs sorted by different age categories from a tertiary general hospital during a 12-year period.

Methods

All positive urine culture results from non-repetitive UTI patients in our hospital from January 2009 to December 2020 were collected retrospectively. The microbial distribution and antibiotic resistance rates were analyzed by WHONET 5.6 software. The etiological profiles sorted by different age categories (newborn, pediatric, adult, and geriatric) and antibiotic resistance rates of the top five pathogens were analyzed.

Results

A total of 13,308 non-repetitive UTI patients were included in our study. Enterococcus faecium was dominant in newborn (45%, n = 105), and replaced by Escherichia coli in pediatric (34%, n = 362), adult (43%, n = 3,416), and geriatric (40%, n = 1,617), respectively. The etiological profiles of different age categories were divergent, sorted by genders (male and female) and ward types (outpatient, inpatient, ICU, and emergency). E. coli, Klebsiella pneumoniae, Enterococcus faecalis, E. faecium, and Pseudomonas aeruginosa were the top five pathogens in all age categories. The resistance rates of cefoperazone–sulbactam and piperacillin–tazobactam in E. coli were low in all age categories. The resistance rates of other cephalosporins, carbapenems, and fluoroqinolones in K. pneumoniae were higher in geriatric patients overall. E. faecium was more resistant than E. faecalis in all age categories. Multidrug resistance increased with age, which was more serious in geriatric patients.

Conclusion

The UTI etiological profiles and antibiotic resistance patterns varied among different age categories, especially in pediatric and geriatric patients; thus, a different antibiotic therapy for various age categories should be considered when initiating empirical antimicrobial therapies.

The Magnitude of Carbapenemase and ESBL Producing Enterobacteriaceae Isolates from Patients with Urinary Tract Infections at Tikur Anbessa Specialized Teaching Hospital, Addis Ababa, Ethiopia

BACKGROUND

The emergence of multidrug-resistant organisms, such as extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE), and carbapenemase-producing Enterobacteriaceae (CPE) is a public health concern. Therefore, this study aimed to determine the magnitude of carbapenemase and ESBL producing bacteria isolated from patients affected by Urinary Tract Infection (UTI).

METHODS

A cross-sectional study was conducted from December 2018 to March 2019 at Tikur Anbessa Specialized Hospital. A total of 120 Enterobacteriaceae isolates from UTI patients were collected and identified on species level using standard microbiological methods. Antimicrobial susceptibility test was determined according to the guidelines of the Clinical and Laboratory Standards Institute. Detection of ESBL production was carried out by using ESBL ChromoSelect Agar medium and the combined disk diffusion. Production of carbapenemase was determined by using Hodge-test and modified carbapenem inactivation method as described in CLSI guidelines.

RESULTS

Out of the total 120 Enterobacteriaceae isolates, 74 (61.7%) were ESBL-producers, and 8 (6.7%) were carbapenemase producers. The most common ESBL producing isolate was E.coli 38 (51.4%) and the most common carbapenemase-producing isolate was K.pneumoniae five (62.5%). Most of the ESBL and carbapenemase-producing isolates were recovered from hospitalized patients 46 (62.2%) and 7 (87.5%) respectively. The rate of ESBL and CPE production was observed high among patients taking antibiotics 64.8% (59/91) and 7.7% (7/91) respectively, but no significant association was observed p > 0.05. Furthermore, about 1.7% (2/120) isolates were found both ESBL and carbapenemase producers. Significant resistances rates were observed in ESBL and CPE isolates.

CONCLUSION

Enterobacteriaceae isolates showed a significantly higher rate of ESBL production. A significant figure of carbapenemase production was observed among Enterobacteriaceae isolates causing UTI. The production of ESBL and CPE enhanced for an increased rate of MDR patterns. Efforts need to be made to introduce a system for tracking and detecting ESBL-PE and CPE-producing bacteria in hospitals, and monitoring dissemination of ESBL and CPE-producing Enterobacteriaceae is strongly recommended.

Clinical Efficacy and Cost Analysis of Antibiotics for Treatment of Uncomplicated Urinary Tract Infections in the Emergency Department of a Tertiary Hospital in Saudi Arabia

Purpose

Uncomplicated urinary tract infections (uUTIs) are one of the main reasons for emergency department (ED) visits. Many antibiotics can be used for uUTI treatment. Currently, no data concerning uUTIs and cost-effectiveness have been reported in Saudi Arabia. This study aimed to investigate antibiotic and cost-effectiveness of beta-lactams, fluoroquinolones, and nitrofurantoin as first-line uUTI treatment.

Patients and Methods

This study was a retrospective cohort based on a five-arm comparative outcome analysis. A cost-effectiveness analysis and comparative group of uUTI treatments in the ED at King Abdulaziz Medical City (KAMC) in Saudi Arabia over a three-month follow-up period was done. The patient group consisted of those presenting to the ED with uUTIs who were treated initially with one of five antibiotics: (1) amoxicillin/clavulanic acid, (2) cefuroxime, (3) ciprofloxacin, (4) nitrofurantoin, or (5) norfloxacin. The main outcomes were effectiveness in terms of cure rates, symptom-free days (SFDs), and estimations of cost-effectiveness among this group.

Results

A total of 865 adult patients who presented with uUTIs were enrolled. Most patients (89.5%) completely recovered, whereas 10.5% of patients were readmitted to the ED with recurrent infections. Effectiveness in terms of the highest cure rate was observed with nitrofurantoin and amoxicillin/clavulanic acid (93.2% and 92.2%, respectively) followed by norfloxacin, cefuroxime, and ciprofloxacin; no significant differences in cure rates were found among these antibiotics. Antibiotic effectiveness in terms of SFDs showed that nitrofurantoin produced the longest SFD period (76 days) followed by amoxicillin/clavulanic acid (69 days). A cost-effectiveness analysis in terms of uUTI cure rates and number of SFDs indicated that nitrofurantoin presented the highest cost-effectiveness followed by amoxicillin/clavulanic acid, norfloxacin, ciprofloxacin, and cefuroxime.

Conclusion

A comparison of five antibiotics for uUTI treatment did not yield clinically significant differences in cure rates. Nitrofurantoin was more cost-effective than the other antibiotics.

Interplay between Phenotypic Resistance to Relevant Antibiotics in Gram-Negative Urinary Pathogens: A Data-Driven Analysis of 10 Years' Worth of Antibiogram Data

The global emergence of antimicrobial resistance (AMR) has become a critical issue for clinicians, as it puts the decades of developments in the medical field in jeopardy, by severely limiting the useful therapeutic arsenal of drugs, both in nosocomial and community-acquired infections. In the present study, a secondary analysis of taxonomic and resistance data was performed, corresponding to urinary tract infections (UTIs) caused by Gram-negative bacteria, detected between 1 January 2008 to 31 December 2017 at the Albert Szent-Györgyi Health Center, University of Szeged. The following were identifiable from the data collected: year of isolation; outpatient (OP)/inpatient (IP) origin of the isolate; taxonomy; and susceptibility/resistance to selected indicator antibiotics. Principal component analysis (PCA) and a correlation matrix were used to determine the association between the presences of resistance against indicator antibiotics in each taxonomic group. Overall, data from n = 16,240 outpatient and n = 13,964 inpatient Gram-negative UTI isolates were included in the data analyses. In E. coli, strong positive correlations were seen between resistance to ciprofloxacin (CIP) and gentamicin (GEN) resistance (OP: r = 0.6342, p = 0.049; IP: r = 0.9602, p < 0.001), whereas strong negative correlations were shown for fosfomycin (FOS) and nitrofurantoin (NIT) resistance (OP: r = -0.7183, p = 0.019; IP: r = -0.7437; p = 0.014). For Klebsiella spp. isolates, CIP resistance showed strong positive correlation with resistance to third-generation cephalosporins (3GC) and GEN (r = 0.7976, p = 0.006 and r = 0.7428, p = 0.014, respectively) in OP isolates, and with resistance to trimethoprim-sulfamethoxazole (SXT) and FOS (r = 0.8144, p = 0.004 and r = 0.7758, p < 0.001, respectively) in IP isolates. For members of the Citrobacter-Enterobacter-Serratia group, the resistance among indicator antibiotics showed a strong positive correlation, with the exception of FOS resistance. In the Proteus-Providencia-Morganella group, the strongest association was noted between CIP and SXT resistance (OP: r = 0.9251, p < 0.001; IP: r = 0.8007; p = 0.005). In the case of OP Acinetobacter spp., CIP showed strong and significant positive correlations with most indicator antibiotics, whereas for IP isolates, strong negative correlations arose among imipenem (IMI) resistance and resistance to other drugs. For Pseudomonas spp., strong and positive correlations were noted among resistance to β-lactam antibiotics and aminoglycosides, with the exception of ceftazidime (CEFT), showing strong, but negative correlations. Though molecular tests and sequencing-based platforms are now considered as the gold-standard for AMR surveillance, standardized collection of phenotypic resistance data and the introduction of Big Data analytic methods may be a viable alternative for molecular surveillance, especially in low-resource settings.

Association between biofilm-production and antibiotic resistance in Escherichia coli isolates: A laboratory-based case study and a literature review

Bacteria can enhance their survival by attaching to inanimate surfaces or tissues, and presenting as multicellular communities encased in a protective extracellular matrix called biofilm. There has been pronounced interest in assessing the relationship between the antibiotic resistant phenotype and biofilm-production in clinically-relevant pathogens. The aim of the present paper was to provide additional experimental results on the topic, testing the biofilm-forming capacity of Escherichia coli isolates using in vitro methods in the context of their antibiotic resistance in the form of a laboratory case study, in addition to provide a comprehensive review of the subject. In our case study, a total of two hundred and fifty (n = 250) E. coli isolates, originating from either clean-catch urine samples (n = 125) or invasive samples (n = 125) were included. The colony morphology of isolates were recorded after 24h, while antimicrobial susceptibility testing was performed using the Kirby-Bauer disk diffusion method. Biofilm-formation of the isolates was assessed with the crystal violet tube-adherence method. Altogether 57 isolates (22.8%) isolates were multidrug resistant (MDR), 89 isolates (35.6%) produced large colonies (>3 mm), mucoid variant colonies were produced in 131 cases (52.4%), and 108 (43.2%) were positive for biofilm formation. Biofilm-producers were less common among isolates resistant to third-generation cephalosporins and trimethoprim-sulfamethoxazole (P = 0.043 and P = 0.023, respectively). Biofilms facilitate a protective growth strategy in bacteria, ensuring safety against environmental stressors, components of the immune system and noxious chemical agents. Being an integral part of bacterial physiology, biofilm-formation is interdependent with the expression of other virulence factors (especially adhesins) and quorum sensing signal molecules. More research is required to allow for the full understanding of the interplay between the MDR phenotype and biofilm-production, which will facilitate the development of novel therapeutic strategies.

Challenges to Early Discharge of Patients with Upper Urinary Tract Infections by ESBL Producers: TMP/SMX as a Step-Down Therapy for Shorter Hospitalization and Lower Costs

Background

Urinary tract infections (UTIs) caused by extended spectrum beta-lactamase (ESBL) producing pathogens have increased and are treated with carbapenem in general. Carbapenem use is associated with prolonged hospitalization or daily outpatient visit. The aim of this study was to investigate patients with UTIs by ESBL-producing pathogens for early discharge using an old oral antibiotic, trimethoprim-sulfamethoxazole (TMP-SMX), which is susceptible to ESBL-producing pathogens.

Methods

Data on UTIs caused by ESBL-producing pathogens from a single tertiary hospital were collected retrospectively. Patients who had been treated with intravenous carbapenems or oral TMP/SMX were included. Patients’ clinical and microbiological outcomes were compared between oral TMP/SMX and ertapenem treatment groups.

Results

A total of 103 patients were included, 21 of whom had been treated with TMP/SMX, whereas 82 with ertapenem. Clinical outcomes between the two groups were not significantly different (TMP/SMX: 90.5%; ertapenem: 84.1%, p = 0.73). The microbiological cure rate was higher in the TMP/SMX group than in the ertapenem group (90.5% vs 58.5%, respectively, p = 0.01). The mean duration of hospitalization was significantly shorter in the TMP/SMX group than in the ertapenem group (8.00 ± 10.50 days vs 14.00 ± 37.00 days, p = 0.07). The mean duration of antibiotic treatment was longer in the ertapenem group than in the TMP/SMX group (16.45 ± 4.77 vs 12.76 ± 5.37 days, p = 0.006).

Conclusion

For susceptible pathogens, TMP/SMX may enable early discharge as an effective oral antibiotic treatment option for UTIs caused by ESBL-positive pathogens. Additionally, use of oral antibiotics can shorten hospital stays and reduce medical costs.

Urinary Tract Infections in Elderly Patients: A 10-Year Study on Their Epidemiology and Antibiotic Resistance Based on the WHO Access, Watch, Reserve (AWaRe) Classification

The ageing of the population—especially in developed countries—has brought on many societal challenges and has significantly contributed to the burden on healthcare infrastructures worldwide. Elderly persons (aged ≥ 65 years) are at higher risk for developing UTIs, due to a range of intrinsic and extrinsic risk factors, and they often delay seeking treatment. A retrospective observational study was performed regarding the epidemiology and resistance of UTIs in elderly patients. Identification of the isolates was carried out using VITEK 2 ID/AST and MALDI-TOF mass spectrometry. Antibiotic resistance in these isolates was assessed based on EUCAST guidelines, and were grouped into the WHO AWaRe (Access, Watch, Reserve) classification of antimicrobials. During the 10-year study period, n = 4214 (421.4 ± 118.7/year) and n = 4952 (495.2 ± 274.6) laboratory-confirmed UTIs were recorded in inpatients and outpatients, respectively. The causative agents showed differentiation among outpatients and inpatients: Escherichia coli (48.14% vs. 25.65%; p = 0.001), Enterococcus spp. (20.15% vs. 21.52%; p > 0.05), Klebsiella spp. (16.28% vs. 16.26%; p > 0.05), Pseudomonas spp. (4.40%vs. 13.36%; p = 0.001); Proteus-Providencia-Morganella group (4.56% vs. 10.96%; p = 0.001); Candida spp. (0.53% vs. 5.98%; p = 0.001); Citrobacter-Enterobacter-Serratia group (1.90% vs. 2.71%; p < 0.05). Significantly higher resistance rates were observed in inpatient isolates for many Access and Watch antibiotics compared to isolates of outpatient origin; in addition, resistance rates were higher in these uropathogens compared to the previously recorded rates in the region. More care should be taken for the diagnosis and treatment of UTIs affecting elderly patients, as they represent a particularly vulnerable patient population.

Antibiotic Resistance Pattern of Extended Spectrum Beta Lactamase Producing Escherichia coli Isolated From Patients With Urinary Tract Infection in Morocco

Extended-spectrum β-lactamases producing Escherichia coli (ESBL-EC) lend resistance to most β-lactam antibiotics. Because of limited treatment options, ESBL-EC infections are generally more difficult to treat, leading to higher hospital costs, reduced rates of microbiological and clinical responses, and a threat to the patient’s life. This study aimed to determine the antibiotic resistance pattern of ESBL-EC isolated from patients with urinary tract infection in Morocco. This retrospective laboratory-based study was conducted at Cheikh Khalifa International University Hospital, Casablanca, from January 2016 to June 2019. A total of 670 urine samples were collected from urinary tract infection patients and processed by standard microbiological methods. In vitro susceptibility testing to different antibiotics of all identified isolates of Escherichia coli (E. coli) was performed following Kirby–Bauer’s disc diffusion method on Mueller–Hinton Agar according to the EUCAST standards. The reviewing of ESBL-EC was confirmed by the appearance of a characteristically shaped zone referred to as a “champagne cork” using the Combined Disk Test. Among a total of 438 E. coli isolated from nonrepetitive urine samples, two hundred fifty-nine (59%) were ESBL-EC, of which 200 (77%) were isolated from adult patients (over the age of 50) and the majority were female. All ESBL-EC isolates were resistant to third-generation cephalosporin and quinolones and sensitive to carbapenem and fosfomycin. Knowledge of antimicrobial resistance patterns in ESBL-EC, the major pathogen associated with urinary tract infection, is indispensable as a guide in choosing empirical antimicrobial treatment.

Characterization of E. coli Phylogroups Causing Catheter-Associated Urinary Tract Infection

PURPOSE

Characterization of different uropathogenic E. coli (UPEC) phylogroups is crucial to understand pathogenesis of urinary tract infection (UTI). The objective of our study was to evaluate the antibiotic resistance pattern, biofilm formation and pathogenicity islands (PAIs) of UPEC phylogroups isolated from catheter-associated UTI (CAUTI) compared to community UTI (Com-UTI).

PATIENTS AND METHODS

This study included 90 UPEC strains recovered from CAUTI and Com-UTI. Antimicrobial susceptibility was tested by the Kirby-Bauer method and extended spectrum beta-lactamase (ESBL) production was confirmed using the combined disk. The biofilm formation was tested using the microtiter plate assay. Main E. coli phylogroups (A, B1, B2 and D) were detected by multiplex PCR and 2 multiplex PCR detected the 8 PAIs.

RESULTS

Antibiotic resistance of UPEC strains showed a similar high resistance in CAUTI and Com-UTI. Isolates from CAUTI significantly produced biofilm higher than Com-UTI strains (68.9% vs 44.4%). In CAUTI and Com-UTI isolates, phylogroup A was the commonest (53.3% vs 48.9%, respectively). PAI IV536 was the most common in the strains from CAUTI (71.1%) and Com-UTI (73.3%). No significant relationship was detected between the studied characters and different phylogroups except the significant resistance to cefotaxime, ceftazidime and aztreonam among phylogroups from CAUTI isolates.

CONCLUSION

Increased antibiotic resistance and ESBLs were detected in UPEC strains from CAUTI and Com-UTI. The strains from CAUTI significantly produced biofilm higher than Com-UTI strains. Phylogroup A was the predominate phylogroup and PAI IV536 was the most prevalent marker in all phylogroups from both types of UTI.

Molecular Basis of Interactions between the Antibiotic Nitrofurantoin and Human Serum Albumin: A Mechanism for the Rapid Drug Blood Transportation

Nitrofurantoin is an antimicrobial agent obtained through the addition of a nitro group and a side chain containing hydantoin to a furan ring. The interactions of the antibiotic with human serum albumin (HSA) have been investigated by fluorescence, UV-VIS, Fourier transform infrared spectroscopy (FTIR) spectroscopy, and protein-ligand docking studies. The fluorescence studies indicate that the binding site of the additive involves modifications of the environment around Trp214 at the level of subdomain IIA. Fluorescence and UV-VIS spectroscopy, displacement studies, and FTIR experiments show the association mode of nitrofurantoin to HSA, suggesting that the primary binding site of the antibiotic is located in Sudlow’s site I. Molecular modeling suggests that nitrofurantoin is involved in the formation of hydrogen bonds with Trp214, Arg218, and Ser454, and is located in the hydrophobic cavity of subdomain IIA. Moreover, the curve-fitting results of the infrared Amide I’ band indicate that the binding of nitrofurantoin induces little change in the protein secondary structure. Overall, these data clarify the blood transportation process of nitrofurantoin and its rapid transfer to the kidney for its elimination, hence leading to a better understanding of its biological effects and being able to design other molecules, based on nitrofurantoin, with a higher biological potential.

Treatment of Asymptomatic Bacteriuria after Implementation of an Inpatient Urine Culture Algorithm in the Electronic Medical Record

Ordering urine cultures in patients without pyuria is associated with the inappropriate treatment of asymptomatic bacteriuria (ASB). In 2015, our institution implemented recommendations based on practice guidelines for the management of ASB and revised the urine culture ordering process to limit cultures in immunocompetent patients without pyuria. The purpose of this study was to determine how the treatment of ASB has changed over time since altering the urine culture ordering process to reduce unnecessary cultures at an academic medical center. A quasi-experimental study was conducted for inpatients with urine cultures from January to March of 2014, 2015, 2016 and 2020. The primary outcome was the antibiotic treatment of asymptomatic bacteriuria for over 24 h. The secondary outcomes were the total days of antibiotic therapy, type of antibiotic prescribed and overall urine culture rates at the hospital. A total of 200 inpatients with ASB were included, 50 at random from each year. In both 2014 and 2015, 70% of the patients with ASB received antibiotic treatment. Antibiotics were prescribed to 68% and 54% of patients with ASB in 2016 and 2020, respectively. The average duration of therapy decreased from 5.12 days in 2014 to 3.46 days in 2020. Although the urine cultures were reduced, there was no immediate impact in the prescribing rates for patients with ASB after implementing this institutional guidance and an altered urine culture ordering process. Over time, there was an observed improvement in prescribing and the total days of antibiotic therapy. This could be attributed to increased familiarity with the guidelines, culture ordering practices or improved documentation. Based on these findings, additional provider education is needed to reinforce the guideline recommendations on the management of ASB.

Antimicrobial resistance patterns of bacterial pathogens their distribution in university teaching hospitals in Zambia

Aim: To determine the antimicrobial resistance patterns of bacterial pathogens from urine, blood and wound infections and their distribution by age, sex and location. Materials & methods: A total of 49,168 samples were collected, processed and analyzed. Results: Multidrug resistance was observed in almost all bacterial pathogens in blood urine and wound swabs. In urine and females odds ratio (OR) = 0.864, p = 0.023, OR = 0.909, p = 0.013 urine and neonates were susceptible to antibiotics OR = 0.859, p = 0.003, OR = 0.741, p < 0.001. Ampicillin resistance was above 90% against Escherichia coli in blood, urine and wound swabs. Conclusion: There was a spike in resistance to imipenem, ciprofloxacin and ampicillin against E. coli, Klebsiella pneumoniae, Proteus mirabilis and Proteus species from all three specimen sources.

Trends in Incidence and Outcomes of Hospitalizations for Urinary Tract Infection among Older People in Spain (2001-2018)

(1) Background: To assess time trends in the incidence and in-hospital outcomes of urinary tract infection (UTI) in older people (≥65 years) in Spain (2001–2018) according to sex and to identify the factors independently associated with in-hospital mortality (IHM). (2) Methods: Using the Spanish National Hospital Database, we analyzed comorbidity, procedures, diagnosis, isolated microorganisms, and outcomes. (3) Results: We included 583,693 admissions (56.76% women). In both sexes, the incidence increased with age over time (p < 0.001). In men and women, the highest IHM was found among the oldest patients (>84 years) with values of 9.16% and 8.6%, respectively. The prevalence of bacteremia increased from 4.61% to 4.98% from 2001 to 2018 (p < 0.001) and sepsis decreased from 3.16% to 1.69% (p < 0.001). The risk of dying increased with age (>84 years) (OR 3.63; 95% CI 3.5–3.78) and with almost all comorbidities. Urinary catheter was a risk factor for women (OR 1.1; 95% CI 1.02–1.18) and protective for men (OR 0.71; 95% CI 0.66–0.76). Isolation of Staphylococcus aureus increased the risk of IHM by 40% among men (OR 1.4; 95% CI 1.28–1.53). After adjusting for confounders, IHM decreased over time. (4) Conclusions: The incidence of UTIs was higher in older patients and increased over time; however, IHM decreased during the same period. Female sex, age, comorbidities, sepsis, and a Staphylococcus aureus isolation increased risk of IHM.

An Investigation of the Male Genitourinary Abscess Originated from Urinary Tract in a Tertiary Hospital, Shanghai, China, from 2004 to 2019

Background

Male genitourinary abscess is one of the serious complications of urinary tract infections (UTIs). There were few researches on the clinical and pathogenic characteristics of male genitourinary abscess.

Patients and Methods

A retrospective observational study was conducted between January 2004 and April 2019. Male patients with genitourinary abscess originated from urinary tract, including sites of scrotum, testis, epididymis, spermatic cord, and prostate, were enrolled. Clinical and microbial records were collected and analyzed, and antimicrobial susceptibility testings were performed according to CLSI standard. Whole-genome sequencing was applied to detect the β-lactamase genes and virulence genes, as well as to determine the multilocus-sequence typing (MLST) of the collected Klebsiella pneumoniae (K. pneumoniae) isolates.

Results

A total of 22 male patients were included. The main clinical symptoms were fever (86.4%), scrotal swelling (68.2%), local skin warmth (59.1%) and ulceration (45.5%). Urinary irritation was often presented in prostate involved abscess. Ultrasound features had a 94.7% positive rate. Surgical treatment, including abscess drainage, was helpful to the prognosis. No matter where the specimens obtained from, including blood, urine or pus, multidrug-resistant K. pneumoniae was the dominant (11 cases, 50.0%) microorganism in positive cultures. Nine of eleven K. pneumoniae isolates had been preserved and recovered. As for MLST typing, all the nine available isolates of K. pneumoniae belonged to the ST11 type and characterized with bla_KPC-2 carbapenemase gene. Virulence genes rmpA2, ybtS, kfuC, wzi, aerobactin genes (iucABCD and iutA) and type 3 fimbriae genes (mrkAD) were identified in all the K. pneumoniae isolates.

Conclusion

It seemed that more patients under 35 years old were vulnerable to genitourinary abscess. There was an increasing trend that multidrug-resistant K. pneumoniae isolates with multiple virulence genes were involved in male genitourinary abscess. Prompt and proper antibiotic use, combined with adequate drainage of the abscess, was important to prognosis.

A spotlight on Raoultella ornithinolytica: A newly emerging life-threatening zoonotic pathogen

The genus Raoultella contains Raoultella ornithinolytica (R. ornithinolytica), which was previously named as Klebsiella ornithinolytica. R. ornithinolytica is a Gram-negative bacillus that belongs to the family Enterobacteriaceae. This pathogen is normally present in aquaculture, and it has been isolated from fish, insects, and wild and domestic birds. Seafood and poultry products are incriminated as sources of R. ornithinolytica infection. Community-acquired human infection with R. ornithinolytica is common. This infection is commonly associated with sepsis, bacteremia, food poisoning, purities, and urinary and respiratory tracts' infections. Rapid acquired resistance of R. ornithinolytica strains is common, and it is related to the development of resistant genes. R. ornithinolytica is considered as a newly emerging life-threatening pathogen world-wide. Hence, it is very important to determine the role of animals and birds in the epidemiological situation of this pathogen as well as the detection of antibiotic resistance genes before treatment.

Bacterial Profile, Antibiotic Susceptibility Pattern and Associated Factors Among Patients Attending Adult OPD at Hawassa University Comprehensive Specialized Hospital, Hawassa, Ethiopia

Background

Urinary tract infection (UTI) is a common health problem occurring when infectious agents colonize, invade, and propagate the urinary tract including the urethra, bladder, renal pelvis, or renal parenchyma. The study aimed to determine the prevalence of symptomatic UTI, drug resistance pattern, and its associated factors among patients attending adult outpatient department (OPD) at Hawassa University Comprehensive Specialized Hospital (HUCSH).

Methods

A cross-sectional study was conducted from October 2018 to February 2019 among adults ≥18 years old with symptoms of UTI. Processing of specimens for culture and identification was done. Antimicrobial susceptibility was done for positive urine cultures. Data entry and analysis were performed using SPSS version 23.0 software. Bivariate and multivariate logistic regression analysis test results were used.

Results

The overall prevalence of symptomatic urinary tract infection was 32.8% (95% CI: 28.3–37.6). The predominant isolated bacteria was E. coli 46 (36.2%) followed by S. aureus 21 (16.5%). Gram-negative bacteria were a high level of resistance to ampicillin (71.4%), and tetracycline (68.2%). Gram-positive bacteria were highly resistant to norfloxacin (77.7%). The overall prevalence of multi-drug resistant isolates was 102 (80.3%). Being female, no formal education, and self-medication history had more likely cause UTI.

Conclusion

Urinary tract infection (UTI) among adults was prevalent in the study area. Being female, educational status and self-medication history had a significant association with UTI. Resistance to ampicillin, tetracycline, and norfloxacin was high. Therefore, culture and antibiotic susceptibility testing should be routinely used for the proper management of patients with UTI.

Study of biofilm formation, structure and antibiotic resistance in Staphylococcus saprophyticus strains causing urinary tract infection in women in Ahvaz, Iran

Staphylococcus saprophyticus is the second most frequent community-acquired causative agent of acute urinary tract infection (UTI). Some strains of S. saprophyticus can create biofilms, increasing their virulence. Once biofilms have been produced, antibiotic resistance is exacerbated. Hence, the aims of the present study were the study of biofilm formation, structure and antibiotic resistance in S. saprophyticus strains causing UTIs in women in Ahvaz, Iran. Overall, 43 S. saprophyticus isolates were recovered from UTIs. Antibiotic resistance pattern and the biofilm production and structure were determined using phenotypic methods. Most S. saprophyticus isolates were resistant to erythromycin, but all isolates were sensitive to linezolid and vancomycin. Fifty-eight per cent of S. saprophyticus were multidrug resistant. Twenty-one per cent of S. saprophyticus isolates harbored the mecA gene. Biofilm formation was observed in 65% of S. saprophyticus isolates and most had polysaccharide matrix. Our data indicate high rates of antibiotic resistance and the capability of biofilm formation among S. saprophyticus isolates. The emergence of antibiotic resistance in the management of UTIs is a serious public health issue. The findings of this study could be used to improve treatment plans to control UTIs. Consequently, increased awareness of the mechanisms underlying biofilm formation and the development of drug resistance will allow UTIs to be more efficiently controlled and treated.

Predictive utility of prior positive urine culture of extended- spectrum β -lactamase producing strains

Rising incidence of extended- spectrum beta-lactamase (ESBL) induced urinary tract infections (UTIs) is an increasing concern worldwide. Thus, it is of paramount importance to investigate novel approaches that can facilitate the identification and guide empiric antibiotic therapy in such episodes. The study aimed to evaluate the usability of antecedent ESBL-positive urine culture to predict the pathogenic identity of future ones. Moreover, the study evaluated the accuracy of selected empiric therapy in index episodes. This was a retrospective study that included 693 cases with paired UTI episodes, linked to two separate hospital admissions within 12 month-period, and a conditional previous ESBL positive episode. Pertinent information was obtained by reviewing patients' medical records and computerized laboratory results. Multivariate analysis showed that shorter interval between index and previous episodes was significantly associated with increased chance of ESBL-positive results in current culture (OR = 0.912, 95CI% = 0.863-0.963, p = 0.001). Additionally, cases with ESBL-positive results in current culture were more likely to have underlying urological/surgical condition (OR = 1.416, 95CI% = 1.018-1.969, p = 0.039). Investigations of the accuracy of current empirical therapy revealed that male patients were less accurately treated compared to female patients (OR = 0.528, 95CI% = 0.289-0.963, p = 0.037). Furthermore, surgical patients were treated less accurately compared to those treated in internal ward (OR = 0.451, 95CI% = 0.234-0.870, p = 0.018). Selecting an agent concordant with previous microbiologic data significantly increased the accuracy of ESBL-UTIs therapy (p<0.001). A quick survey of the previous ESBL urine culture results can guide practitioners in the selection of empiric therapy for the pending current culture and thus improve treatment accuracy.

The Impact of COPD in Trends of Urinary Tract Infection Hospitalizations in Spain, 2001-2018: A Population-Based Study Using Administrative Data

(1) Background: To examine trends in incidence and outcomes of urinary tract infections (UTIs) among men and women with or without chronic obstructive pulmonary disease (COPD), and to identify the predictors for in-hospital mortality (IHM). (2) Methods: We included patients (aged ≥40 years) who were hospitalized with UTIs between 2001 and 2018. Data were collected from the Spanish National Hospital Discharge Database. (3) Results: We identified 748,458 UTI hospitalizations, 6.53% with COPD. The UTIs incidence increased over time. It was 1.55 times higher among men COPD patients than among non-COPD men (incidence rate ratio (IRR) 1.55; 95% CI 1.53-1.56). The opposite happened in women with COPD compared to non-COPD women (IRR 0.30; 95% CI 0.28-0.32). IHM was higher in men with COPD than non-COPD men (5.58% vs. 4.47%; p < 0.001) and the same happened in women (5.62% vs. 4.92%; p < 0.001). The risk of dying increased with age and comorbidity, but the urinary catheter was a protective factor among men (OR 0.75; 95% CI 0.64-0.89). Multivariable analysis showed a significant reduction in the IHM over time for men and women with COPD. Suffering from COPD only increased the risk of IHM among men (OR 1.07; 95% CI 1.01-1.13). (4) Conclusions: The incidence of UTIs increased over time. Suffering COPD increased the risk of IHM among men, but not among women.

Detection of VIM, NDM and OXA-48 producing carbapenem resistant Enterobacterales among clinical isolates in Southern Hungary

Infections caused by carbapenem-resistant Enterobacterales (CRE) present an important therapeutic problem, as there are limited number of effective therapeutic alternatives available. In this study, phenotypic and genotypic methods were used to characterize carbapenemase-production and other resistance-determinants (AmpC and ESBL-production, efflux pump-overexpression) in 50 isolates (Klebsiella spp. n = 35, Escherichia coli n = 12 and Enterobacter cloacae complex n = 3) collected at the Albert Szent-Györgyi Clinical Center (University of Szeged) between 2014 and 2017. Minimum inhibitory concentrations of meropenem, sulfamethoxazole/trimethoprim, tigecycline, amikacin, moxifloxacin, colistin and fosfomycin were also determined. 24% of isolates were AmpC-producers, while 30% carried blaCTX-M ESBL-genes. Carbapenemase-genes were detected in 18 (36%) of the tested isolates: in 2 isolates blaNDM, in 6 isolates blaOXA-48-like and in 12 isolates, blaVIM was detected by PCR. The species-distribution for isolates positive for carbapenemase-genes was the following: Klebsiella pneumoniae n = 11, Klebsiella oxytoca n = 1, E. coli n = 5, E. cloacae complex n = 1. Efflux pump-overexpression based on the PAβN-screening agar was shown in n = 3 of the tested strains. In nine isolates (18%), carbapenemase and ESBL-genes were detected simultaneously. Highest levels of resistance were noted for fosfomycin (74%) and moxifloxacin (70%), while all isolates were susceptible to colistin. Among applied phenotypic tests in this study the modified carbapenem inactivation method (mCIM) proved to be the most accurate one compared to that of PCR results.

The Importance of Reporting Clinical and Epidemiological Data in Urology: Local Experiences and Insights from the International Literature

Pathologies of the genito-urinary tract are responsible for a considerable disease burden worldwide, leading to significant losses of income, lost working days, increased expenditures for national healthcare systems, and decreased quality of life (QoL) in the affected patients. Among these diseases, infections and malignancies in this anatomical region are some of the most important illnesses in human medicine; nevertheless, benign prostate hyperplasia (BPH), erectile dysfunction, hypospadias, urinary incontinence, and vesicoureteral reflux are also relevant disorders affecting millions. The publication of various microbiological and clinical studies in urology from different geographical regions has important ramifications from the standpoint of epidemiology: on one hand, reported data may influence the development of therapeutic guidelines for urinary tract infections (UTIs) (empiric antibiotic-therapy) and malignancies (including classical cytotoxic drug protocols and next-generation anticancer therapies) both locally and internationally; on the other hand, the relevant stakeholders and government representatives often base their decisions on published evidence. Therefore, novel studies in the field of urology are strongly encouraged to maintain and improve the high standard of patient care internationally and to ensure continuous information supply for international datasets on the causative agents of UTIs and cancer registries. The present Editorial aims to highlight some relevant studies published from the field of urology in Medicina over the last several years.

Economic Burden of Patients with Bloodstream Infections Caused by Extended-Spectrum β-Lactamase-Producing Escherichia coli

Background

The prevalence of infections with extended-spectrum β-lactamase-producing Escherichia coli (ESBL-EC) is increasing worldwide, but the economic impact of ESBL-EC bloodstream infection (BSI) has not been comprehensively evaluated.

Patients and Methods

A retrospective cohort including patients hospitalized at a tertiary hospital between January 2013 and December 2016 who were confirmed with a BSI of ESBL-EC or non-ESBL-EC was set. Clinical data and medical costs were collected by chart review of electronic and paper medical records. The economic burden was evaluated with disability-adjusted life years (DALYs).

Results

A total of 580 patients with E. coli BSI, comprising 333 patients (57.4%) with ESBL-EC BSI and 247 patients (42.6%) with non-ESBL-EC BSI, were identified. There were no significant differences in comorbidity and severity of patients between ESBL-EC and non-ESBL-EC BSI. The median length of stay (LOS) after bacteremia was 12 days for ESBL-EC (interquartile range, 7 to 21) versus 11 days for non-ESBL-EC (interquartile range, 7 to 21) (P = 0.38), and appropriate empirical antimicrobial therapy occurred in 87.4% versus 89.9% (P = 0.353). The mortalities were 20.1% versus 17.4% (P = 0.41). Patients with ESBL-EC did not have significantly different in-hospital medical costs to those with non-ESBL-EC (median, $8048.68 vs $7476.84, respectively, with a difference of $571.84, P = 0.321). In the non-ESBL-EC group, 247 patients lost 531.05 DALYs in total, with an average of 2.15 DALYs per person, while in the ESBL-EC group, 333 patients lost 692.64 DALYs in total, with an average of 2.08 DALYs per person. There is no significant difference in average DALYs (P = 0.343).

Conclusion

In conclusion, patients with BSI due to ESBL-EC did not cost more than patients with BSI due to non-ESBL-EC. This phenomenon may be attributed to timely and effective antibiotic treatment, but the initial empiric therapy with second- or third-line antibiotics in non-ESBL-EC BSI should be corrected.

Resistance and Heteroresistance to Colistin in Escherichia coli Isolates from Wenzhou, China

Background

Colistin is being administered as last-line therapy for patients that have failed to respond to other available antibiotics that are active against Escherichia coli. The underlying mechanisms of colistin resistance and heteroresistance remain largely uncharacterized. The present study investigated the mechanisms of resistance and heteroresistance to colistin in Escherichia coli isolates from Wenzhou, China.

Materials and Methods

Colistin resistance was detected by the broth microdilution method (BMD). Colistin heteroresistance was determined by population analysis profiles (PAPs). The polymerase chain reaction (PCR) was conducted to detect mcr-1, mcr-2, mcr-3, pmrA, pmrB, phoP, phoQ and mgrB, and quantitative real-time PCR (qRT-PCR) was used to determine the expression levels of mcr-1, pmrC, pmrA and pmrB. Lipid A characterization was conducted by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS).

Results

0.69% (2/291) of Escherichia coli strains were resistant to colistin, whereas the heteroresistance rate reached 1.37% (4/291). mcr-1, the mobile colistin-resistance gene, was present in the two resistant isolates. The substitutions in PmrB were detected in the two heteroresistant isolates. The transcripts levels of the pmrCAB operon were upregulated in two of the heteroresistant isolates. carbonylcyanide m-chlorophenylhydrazone (CCCP) was able to reverse colistin resistance of all isolates tested and exhibited a significantly higher effect on colistin-heteroresistant isolates. MALDI-TOF MS indicated that the additional phosphoethanolamine (PEtn) moieties in lipid A profiles were present both in colistin-resistant and heteroresistant isolates.

Conclusion

The present study was the first to investigate the differential mechanisms between colistin resistance and heteroresistance. The development of colistin heteroresistance should be addressed in future clinical surveillance.

Clinical Characteristics and Risk Factors for Bloodstream Infection Due to Carbapenem-Resistant Klebsiella pneumoniae in Patients with Hematologic Malignancies

Purpose

The aim was to examine the clinical characteristics and risk factors for bloodstream infection (BSI) due to carbapenem-resistant Klebsiella pneumoniae (CRKP) in patients with hematologic malignancies.

Materials and Methods

A single-centre, retrospective case–control study representing 734 patients with hematologic malignancies between January 1, 2017, and December 31, 2018, was conducted. Demographic and clinical data were collected from the hospital electronic medical records system.

Results

Among the 734 patients with hematologic malignancies, 3% (22/734) of the patients developed CRKP BSI during their hospitalization. Overall 28-day all-cause mortality reached 77.3% (17/22). Patients with Pitt bacteremia score (PBS) >4, pneumonia and septic shock were more frequent in the non-survivors versus the survivors. Compared with the non-survivors in antimicrobial treatment, combination therapy of tigecycline and polymyxin B was more common in the survivors. The independent risk factors associated with CRKP BSI were CRKP rectal colonization (OR, 11.067; CI=4.43–27.644; P<0.001; 3 points), severe neutropenia (OR, 4.095; CI=0.876–19.141; P=0.073; 1 point) and invasive mechanical ventilation (IMV) within the previous 30 days to onset of BSI (OR, 18.444; CI=1.787–190.343; P=0.014; 4 points). The total risk score of ≥5 indicated that the probability of CRKP BSI occurrence was above 48%.

Conclusion

CRKP BSI in patients with hematologic malignancies is associated with high mortality. The risk factor-based prediction model might help clinicians to start prompt effective anti-infective therapy in patients with suspicion of CRKP BSI and improve outcomes.

Sitafloxacin has a potent activity for eradication of extended spectrum β-lactamase-producing fluoroquinolone-resistant Escherichia coli forming intracellular bacterial communities in uroepithelial cells

INTRODUCTION

Eradication of asymptomatic bacteriuria (ASB) before urological procedures is important to reduce the risk for infectious complications after surgery. However, the appropriate regimen for antimicrobial treatment has not been fully determined. We experienced continuous (over 10 months) isolation of extended spectrum β-lactamase (ESBL)-producing fluoroquinolone-resistant Escherichia coli from urine of an asymptomatic patient. The four isolates obtained (SMESC1 to 4) were international high-risk clones of O25b:H4-ST131-H30R, and originated from one strain, as revealed by the whole genome sequences. Although the patient received meropenem (MEPM) and fosfomycin (FOM), to which the strains were susceptible before the urological procedures, they could not be eradicated.

METHODS

To explore the reason for the continuous isolation even after MEPM and FOM administration, antimicrobial killing of adherent and/or intracellular bacterial communities (IBC) formed by coculture of the E. coli cells and T24 bladder epithelial cells were examined.

RESULTS

FOM and levofloxacin did not decrease viable E. coli cells compared with gentamicin. MEPM partly decreased them, and sitafloxacin (STFX) decreased them most potently. These observations indicate that E. coli can survive in the urinary tract under antimicrobial administration, and some antimicrobials such as FOM and MEPM cannot eradicate E. coli in uroepithelial cells. Adhesion on urinary epithelial cells and/or IBC formation might result in continuous isolation from the urinary tract and recurrence of ASB and urinary tract infections.

CONCLUSIONS

The present study suggests that STFX is a promising optional agent for the eradication of ESBL-producing fluoroquinolone-resistant E. coli in the urinary tract before urological procedures.

Antibiogram Signatures of Some Enterobacteria Recovered from Irrigation Water and Agricultural Soil in two District Municipalities of South Africa

This study was undertaken to evaluate the antibiogram fingerprints of some Enterobacteria recovered from irrigation water and agricultural soil in two District Municipalities of the Eastern Cape Province, South Africa using standard culture-based and molecular methods. The prevalent resistance patterns in the isolates follow the order: Salmonella enterica serovar Typhimurium [tetracycline (92.3%), ampicillin (69.2%)]; Enterobacter cloacae [amoxicillin/clavulanic acid (77.6%), ampicillin (84.5%), cefuroxime (81.0%), nitrofurantoin (81%), and tetracycline (80.3%)]; Klebsiella pneumoniae [amoxicillin/clavulanic acid (80.6%), ampicillin (88.9%), and cefuroxime (61.1%)]; and Klebsiella oxytoca [chloramphenicol (52.4%), amoxicillin/clavulanic acid (61.9%), ampicillin (61.9%), and nitrofurantoin (61.9%)]. Antibiotic resistance genes detected include tetC (86%), sulII (86%), and bla_AmpC (29%) in Salmonella enterica serovar Typhimurium., tetA (23%), tetB (23%), tetC (12%), sulI (54%), sulII (54%), catII (71%), bla_AmpC (86%), bla_TEM (43%), and bla_PER (17%) in Enterobacter cloacae., tetA (20%), tetC (20%), tetD (10%), sulI (9%), sulII (18%), FOX (11%) and CIT (11%)-type plasmid-mediated AmpC, bla_TEM (11%), and bla_SHV (5%) in Klebsiella pneumoniae and bla_AmpC (18%) in Klebsiella oxytoca. Our findings document the occurrence of some antibiotic-resistant Enterobacteria in irrigation water and agricultural soil in Amathole and Chris Hani District Municipalities, Eastern Cape Province of South Africa, thus serving as a potential threat to food safety.

Emergence of Raoultella ornithinolytica isolated from chicken products in Alexandria, Egypt

Background and Aim:

Raoultella ornithinolytica is one of the emerging gram-negative bacteria, which associated with foodborne illness. Researches affirmed that distinguish between R. ornithinolytica and Klebsiella oxytoca are difficult, as they are phylogenetic related. The evolution of multidrug resistance of Raoultella strains gained more concern for recognition of the pathogen which supports in controlling the disease and minify its threat. This study sought to find a reliable tool for the identification of Raoultella ornithinolytica, isolated from chicken product samples, and assessed the resistance profile of R. ornithinolytica using antibiogram sensitivity tests.

Materials and Methods:

Forty samples of chicken products were collected between January and September 2019 from different markets in Alexandria Governorate, Egypt. The products included nuggets, strips, burgers, luncheon meats, pane, frankfurters, and minced chicken meat. The samples were transferred to the Reference Laboratory. The samples were subjected to isolation, biochemical reaction testing, phenotypic system analytical profile index (API) E20, and a detection of antimicrobial susceptibility test. Phenotypic identification was confirmed through matrix-assisted laser-desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS).

Results:

Thirty-three bacterial isolates (82.50%) out of 40 samples were isolated into pure cultures from the chicken samples. Three isolates (9.09%) were positive for R. ornithinolytica, while 30 isolates (90.91%) exhibited growth characters for different pathogens (Escherichia coli, Enterobacter aerogenes, Proteus vulgaris, R. ornithinolytica, and Klebsiella pneumoniae). The isolates of R. ornithinolytica were resistant to five types of antibiotics and sensitive to two types of antibiotics.

Conclusion:

This study reported the first case of R. ornithinolytica found in chicken products in Egypt. Phenotypic system API 20E and MALDI-TOF MS were found to be reliable tools for confirming the diagnosis of R. ornithinolytica. As it provides rapid identification with high sensitivity and specificity for R. ornithinolytica, which often do not require a molecular procedure for confirmation.

Plasmid Profiling and Occurrence of β-Lactamase Enzymes in Multidrug-Resistant Uropathogenic Escherichia coli in Kathmandu, Nepal

INTRODUCTION

Extended-spectrum β-lactamases (ESBL) among Gram-negative bacteria, predominantly Escherichia coli (E. coli), in Nepal, have been rising. The main objectives of this study were to determine the prevalence of uropathogenic E. coli, antibiotic resistance, ESBLs, ABLs (AmpC type β-lactamases), MBLs (metallo-β-lactamases) and KPCs (Klebsiella pneumoniae carbapenemases) and their correlation with plasmid profiling patterns among patients with urinary tract infections in a tertiary hospital in Kathmandu, Nepal.

METHODS

The mid-stream urine samples collected from patients were inoculated in cystine-lactose-electrolyte-deficient (CLED) agar plates. E. coli producing ESBLs, ABLs, MBLs/KPC were identified phenotypically using standard microbiological methods. Plasmids were extracted by alkaline lysis method from E. coli isolates and profiled using agarose gel electrophoresis.

RESULTS

Out of the total 2661 urine samples, E. coli were isolated in 64.34% (507/788), among which 170 (33.53%) were multidrug-resistant (MDR) isolates. All MDR isolates were resistant to amoxicillin and third-generation cephalosporins but were highly sensitive to imipenem (94.12%, 160/170), amikacin (92.94%, 158/170) and nitrofurantoin (86.47%, 147/170). Among 170 MDR isolates, 78.2% (133/170) were ESBLs, 46.3% (50/170) were AmpC, 11.2% (19/170) were MBL and 0.6% (1/170) were KPC producers. Coproduction of β-lactamases was detected in 24.12% (41/170) of isolates. E. coli isolates showed one plasmid (>33.5 kb), which was present in all the isolates. Overall, 44 different plasmid profile groups were identified based on molecular weight and number of plasmids. β-Lactamase producers were relatively resistant to the higher number of antibiotics tested (≤10) than non-producers (≤8), and the number of plasmids were higher in β-lactamase producers (≤7) than those in non-producers (≤5).

CONCLUSION

The higher prevalence of the ESBLs, AmpCs, KPCs and MBLs along with their coproduction in E. coli isolates highlights the importance of routine surveillance of ESBLs, AmpCs, KPCs and MBLs in microbiology laboratories using various phenotypic methods.

Differential epidemiology and antibiotic resistance of lactose-fermenting and non-fermenting Escherichia coli: Is it just a matter of taste?

Urinary tract infections (UTIs) are some of the most common infections affecting humans worldwide. Occurrence of atypical, lactose non-fermenting, biochemically "inactive" strains of E. coli in clinical material has been described in the literature, which may cause a significant diagnostic challenge. The present retrospective microbiological study was carried out using isolates and data collected between January 1, 2013, and December 31, 2017, at the Institute of Clinical Microbiology. n = 24,285 positive urine samples were noted during the study period, out of which, samples positive for either lac + and lac- E. coli were included in the analysis. E. coli represented n = 7075 (55.8% ± 4.6%) of outpatient and n = 4916 (42.4% ± 3.6%) of inpatient isolates. n = 401 (3.3%; 80.2 ± 14.6/year) lac- E. coli isolates were identified from urinary tract infections. The ratio of lac- E. coli isolates was significantly higher in outpatient samples (262 vs. 139). Resistance levels of lac- isolates for antibiotics commonly used for treating UTIs were significantly higher for both inpatient and outpatient isolates: norfloxacin, ciprofloxacin, fosfomycin and nitrofurantoin. It is essential to pay attention to the presence of lac- strains, and their omission from clinical material during diagnostic procedures may have significant consequences for epidemiological studies and therapy.

From Gene to Protein-How Bacterial Virulence Factors Manipulate Host Gene Expression During Infection

Bacteria evolved many strategies to survive and persist within host cells. Secretion of bacterial effectors enables bacteria not only to enter the host cell but also to manipulate host gene expression to circumvent clearance by the host immune response. Some effectors were also shown to evade the nucleus to manipulate epigenetic processes as well as transcription and mRNA procession and are therefore classified as nucleomodulins. Others were shown to interfere downstream with gene expression at the level of mRNA stability, favoring either mRNA stabilization or mRNA degradation, translation or protein stability, including mechanisms of protein activation and degradation. Finally, manipulation of innate immune signaling and nutrient supply creates a replicative niche that enables bacterial intracellular persistence and survival. In this review, we want to highlight the divergent strategies applied by intracellular bacteria to evade host immune responses through subversion of host gene expression via bacterial effectors. Since these virulence proteins mimic host cell enzymes or own novel enzymatic functions, characterizing their properties could help to understand the complex interactions between host and pathogen during infections. Additionally, these insights could propose potential targets for medical therapy.

Epidemic Characteristics of Carbapenem-Resistant Klebsiella pneumoniae in the Pediatric Intensive Care Unit of Yanbian University Hospital, China

Introduction

Carbapenem-resistant Enterobacteriaceae (CRE) pose a serious threat to clinical patient management and public health, as they are generally resistant to most antibiotics and cause infections with high mortality rates. Klebsiella pneumoniae ranks second among Enterobacteriaceae species that cause nosocomial infections. In this study, we investigated the epidemic characteristics of carbapenem-resistant K. pneumoniae (CRKP) in the pediatric intensive care unit (PICU) of Yanbian University Hospital.

Materials and Methods

A total of 14 non-duplicate CRKP strains, collected from March 2015 to November 2019, were subjected to automated microbial identification and antimicrobial susceptibility tests using the Phoenix-100 ID/AST system. The strains were also subjected to genotypic resistance testing, polymerase chain reaction assays to detect genes encoding carbapenemases and other β-lactamases, multi-locus sequence typing (MLST), and pulsed-field gel electrophoresis (PFGE)-based homology analysis.

Results

Two carbapenemase genes, KPC-2 and NDM-1 (in eight and six strains, respectively), were detected. MLST enabled the division of the strains into two sequence types, ST11 and ST1224 (containing eight and six strains, respectively). PFGE results classified the 14 strains into clonotypes A–D, of which clonotypes A and B belonged to ST11, while clonotypes C and D belonged to ST1224.

Conclusion

Our study reveals that epidemics of the KPC-2-ST11 and NDM-1-ST1224 strains occurred in the PICU of Yanbian University Hospital. Surveillance and strict implementation of prevention and control measures are crucial to prevent the occurrence and rapid spread of nosocomial infections.

Pathogenic Characteristics of and Variation in Vibrio parahaemolyticus Isolated from Acute Diarrhoeal Patients in Southeastern China from 2013 to 2017

Objective

Vibrio parahaemolyticus is a major diarrhoea-inducing pathogen in coastal areas. In this study, we analysed the pathogenic characteristics of and variation in V. parahaemolyticus isolated from acute diarrhoeal patients in seven hospitals in different areas of southeastern China from 2013 to 2017.

Methods

The fecal specimens of patients with acute diarrhoea were collected. The routine microbiological test procedure combining with MALDI Biotyper microbial identification system was carried out to identify the V. parahaemolyticus. Serum agglutination tests, PCR for the detection of virulence-related genes and the Kirby-Bauer method to test for antimicrobial sensitivity were performed.

Results

From 2013 to 2017 in southeastern China, a total of 1220 V. parahaemolyticus strains were isolated from 16,504 stool specimens collected from acute diarrhoeal patients, and the annual isolation rate fluctuated between 6.1% and 8.7%. In total, 96.7% of the V. parahaemolyticus isolates were isolated in summer and autumn, mainly in people aged 18–44. Fifty-nine serotypes were identified, and the agglutination rate of the O antigen was 98.5%. From 2014 to 2016, the dominant serotype was O3:K6, while in 2013 and 2017, it was O4:KUT. The serotypes of O3:K6, O4:KUT, O4:K8, O3:KUT, O10:K60, O1:KUT and O1:K36 appeared every year from 2013 to 2017. O4:K6 and OUT:K6 began to appear after 2014 and 2015, respectively. A total of 49.5% of the strains belonged to the pandemic group, which consisted of 26 serotypes. Most isolates were sensitive to common antibiotics, excluding ampicillin.

Conclusion

V. parahaemolyticus is still present at a high level in southeastern China. Although the pandemic O3:K6 serotype is predominant, new serotypes continue to emerge, especially the O4:KUT serotype, which exceeded O3:K6 in prevalence in some years. Long-term surveillance is necessary to prevent the outbreak or transmission of this pathogen.

Raoultella ornithinolytica: Emergence and Resistance

Raoultella ornithinolytica is an encapsulated Gram-negative, oxidase-negative, catalase-positive, aerobic, non-motile rod that belongs to the Enterobacteriaceae family. This bacterium was initially classified in the genus Klebsiella as Klebsiella ornithinolytica, until the creation of the genus Raoultella in 2001. R. ornithinolytica is usually found in water environments and soil, and due to its ability to convert histidine to histamine, it has been associated with histamine poisoning in humans. R. ornithinolytica is an emerging entity in human infections, with several reports of virulent infections in comorbid at-risk patients. Increasing reports are potentially due to better and more precise identification tools. The objective of this article is to provide a comprehensive review of reported cases of R. ornithinolytica infections, the emergent virulence of described multiresistant strains, and an overview of currently used identification methods.

Carbapenem-Resistant but Cephalosporin-Susceptible Pseudomonas aeruginosa in Urinary Tract Infections: Opportunity for Colistin Sparing

This paper briefly reports the occurrence and epidemiology of carbapenem-resistant but cephalosporin-susceptible (Car-R/Ceph-S) Pseudomonas aeruginosa isolates from urinary tract infections (UTIs) in a tertiary-care hospital in the Southern Region of Hungary, and the phenotypic characterization of the possible resistance mechanisms in these isolates. Isolates and data were collected regarding P. aeruginosa UTIs corresponding to the period between 2008 and 2017. Susceptibility testing was performed using the Kirby–Bauer disk diffusion method; minimum inhibitory concentrations (MICs) of the isolates were determined using E-tests. The phenotypic detection of ampicillin C-type (AmpC) β-lactamases, efflux pump overexpression and carbapenemase production was also performed. P. aeruginosa represented n = 575 (2.72% ± 0.64%) from outpatient, and n = 1045 (5.43% ± 0.81%) from inpatient urinary samples, respectively. Based on the disk diffusion test, n = 359 (22.16%) were carbapenem-resistant; in addition to carbapenems, n = (64.34%) were also resistant to ciprofloxacin; n = (60.17%) to gentamicin/tobramycin; n = (58.51%) to levofloxacin; and n = (27.57%) to amikacin. From among the carbapenem-resistant isolates, n = 56 (15.59%) isolates were multidrug-resistant, while n = 16 (4.46%) were extensively drug-resistant. From among the Car-R/Ceph-S isolates (n = 57), overexpression of AmpC was observed in n = 7 cases (12.28%); carbapenemase production in n = 4 (7.02%); while overexpression of efflux pumps was present in n = 31 (54.39%) isolates. To spare last-resort agents, e.g., colistin, the use of broad-spectrum cephalosporins or safe, alternative agents should be considered in these infections.