Extended-spectrum β-lactamase-producing bacteria causing community-acquired urinary tract infections in children

Race and ethnicity as risk factors for colonization and infection with key bacterial pathogens: a scoping review

Background

Racial and ethnic disparities in infectious disease burden have been reported in the USA and globally, most recently for COVID-19. It remains unclear whether such disparities also exist for priority bacterial pathogens that are increasingly antibiotic-resistant. We conducted a scoping review to summarize published studies that report on colonization or community-acquired infection with pathogens among different races and ethnicities.

Methods

We conducted an electronic literature search of MEDLINE®, Daily, Global Health, Embase, Cochrane Central, and Web of Science from inception to January 2022 for eligible observational studies. Abstracts and full-text publications were screened in duplicate for studies that reported data for race or ethnicity for at least one of the pathogens of interest.

Results

Fifty-four observational studies in 59 publications met our inclusion criteria. Studies reported results for Enterobacterales, Enterococcus faecium, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Staphylococcus aureus, and were conducted in Australia, Brazil, Israel, New Zealand, and USA. USA studies most often examined Black and Hispanic minority groups with studies regularly reporting a higher risk of these pathogens in Black persons and mixed results for Hispanic persons. Ethnic minority groups (e.g. Bedouins in Israel, Aboriginals in Australia) were often reported to be at a higher risk in other countries.

Conclusion

Sufficient evidence was identified in this scoping review justifying future systematic reviews and meta-analyses evaluating the relationship between community-acquired pathogens and race and ethnicity. However, we noted that only a fraction of studies reported data stratified by race and ethnicity, highlighting a substantial gap in the literature.

High Rates of ESBL-producing and Gentamycin-resistant Gram-negative Bacteria During the First Week of Life: A Multicenter Cross-sectional Study Among Infants Younger Than 2 Months With Urinary Tract Infection

INTRODUCTION

Reducing the risk of renal scarring in infants with urinary tract infection (UTI) necessitates timely and effective administration of antimicrobial treatment. The Israeli Medical Association recommends the empirical use of gentamicin and ampicillin for febrile infants younger than 2 months with suspected UTI. We aimed to assess the prevalence of Extended Spectrum Beta-Lactamase (ESBL)-producing and gentamicin-resistant Gram-negative UTI among infants younger than 2 months.

METHODS

A multicenter retrospective cross-sectional study of infants younger than 2 months with UTI who visited Clalit Health Services pediatric emergency departments between January 1, 2016, and December 31, 2021. The primary outcome measure was the prevalence of ESBL-associated and gentamicin-resistant UTI. The secondary outcome measure was the factors associated with such resistant bacteria.

RESULTS

Overall, 1142 infants were included. Sixty-five (5.7%) and 64 (5.6%) infants had gentamicin-resistant and ESBL-producing Gram-negative UTI, respectively. Forty-two percent of ESBL-associated UTI were gentamicin-resistant. Higher ESBL rates were found during first week of life (14.8% versus 4.1%-7.7%; P = 0.009). Similarly, higher rates of gentamicin resistance were found in this age group (11.2%). Admission rate to pediatric intensive care units (ICUs) was higher in infants with ESBL-associated UTI (9.8% versus 3.5%; P = 0.015). Gestational bacteriuria, previous neonatal ICU admission or gender were not associated with either gentamicin or ESBL-producing resistance.

CONCLUSIONS

Our findings support the current recommendations for empirical intravenous treatment. However, modification of the treatment protocol should be considered for infants younger than 7 days, who had higher rates of ESBL-producing and gentamicin-resistant Gram-negative UTI.

A Case-Control Study Evaluating Risk Factors and Outcomes of Hospitalized Children With ESBL-UTI

Urinary tract infections (UTIs) are among the most common causes of hospitalization in children, with a rising prevalence of extended-spectrum beta-lactamase-producing organisms (ESBL). The purpose of this study was to identify risk factors and treatment outcomes of children with ESBL-UTI. A retrospective case-control study of hospitalized children was performed from July 2014 till December 2017. Medical records from patients with a positive urine culture were reviewed and included in the study if they met criteria for UTI. Cases were defined as ESBL-UTI, while controls were defined as non-ESBL-UTI patients. This study confirmed that there are certain risk factors, such as previous UTI, recent antibiotic use, urinary tract abnormalities, recent hospital admission, and nonrenal comorbidities, that are associated with ESBL-UTI. Most of the patients with ESBL-UTI responded to discordant antibiotics. Other significant outcomes in patients with ESBL-UTI included a longer length of stay and longer intravenous antibiotic therapy.

Trends and risk factors of extended-spectrum beta-lactamase urinary tract infection in Chinese children: a nomogram is built and urologist should act in time

BACKGROUND

To investigate the etiological characteristics and risk factors of extended-spectrum beta-lactamase (ESBL) urinary tract infection (UTI) and construct a corresponding nomogram to predict the probability of ESBL(+) UTI.

METHODS

We retrospectively reviewed the records among patients experiencing UTI events in Chongqing Medical University Affiliated Children's Hospital from 1994 and 2019.

RESULTS

A total of 854 patients with UTI were evaluated and ESBL-producing bacteria increased significantly. Significant potential risk factors of ESBL-UTI were congenital urological abnormalities, vesicoureteral reflux, neurologic disorder, age <12 months, fever and previous use of antibiotics. On logistic regression analysis, neurological disorder (OR =8, 95% CI: 1.845-34.695) and antibiotics administration in the last 3 months (OR =4.764, 95% CI: 3.114-7.289) were identified as an independent significant risk factor for ESBL-UTI. The nomogram generated was well calibrated for all predictions of ESBL+ probability, and the accuracy of the model nomogram measured by Harrell's C statistic (C-index) was 0.741.

CONCLUSIONS

The current situation of multiple bacterial antibiotic resistance has become a worrisome issue in UTI and early identification of ESBL production is important in terms of appropriate treatment and effective infection control. We may choose broad-spectrum antibiotics as empirical antibiotics for UTI among children with neurological disease and used antibiotic in the last three months.

Impact of Third-Generation Cephalosporin Resistance on Recurrence in Children with Febrile Urinary Tract Infections

Background: The purpose of this study was to investigate the association between third-generation cephalosporin resistance and urinary tract infection (UTI) recurrence in patients who underwent voiding cystourethrogram (VCUG). Methods: In this retrospective study, data were obtained from hospitalized pediatric patients who had a first febrile UTI episode and subsequently underwent VCUG. Information based on VCUG was mandatory to identify the presence of vesicoureteral reflux (VUR). A multivariable logistic model was used to identify the risk factors for recurrence. Recurrence was divided into early (90-day) and late (1-year), and sensitivity analyses were performed according to each definition. The estimates of all the statistical models were internally validated using bootstrap samples. Results: A total of 210 patients were included, and the overall recurrence rate of UTI was 26.2% (55 of 210). Third-generation cephalosporin resistance was a significant risk factor for early recurrence (odds ratio: 2.79 [1.08–7.20]) but not for late recurrence. Sensitivity analyses showed that third-generation cephalosporin resistance was a significant risk factor for 60-day recurrence but not for 180-day recurrence. A VUR grade ≥ 3 was identified as a consistent risk factor for both early and late recurrence. Conclusions: Third-generation cephalosporin resistance was a significant risk factor for the early recurrence of pediatric UTI in patients who underwent VCUG.

Emergence of Extended-Spectrum β-Lactamase-Producing Pathogens in Community-Acquired Urinary Tract Infections Among Infants at a Pediatric Emergency Department

BACKGROUND

Extended-spectrum β-lactamase (ESBL)-producing pathogens are common among adults and are associated with extended and multiple hospitalizations. They cause urinary tract infections (UTIs) among children with known risk factors such as urinary tract abnormalities and antimicrobial prophylaxis. The emergence of UTIs caused by ESBL-producing organisms among infants has not been well characterized.

OBJECTIVE

We sought to describe the incidence and current clinical management of infants who were diagnosed with UTIs caused by ESBL-producing organisms at a pediatric emergency department (ED). In addition, we sought to describe risk factors associated with inpatient hospitalization for UTIs caused by ESBL-producing organisms.

METHODS

We retrospectively identified infants who were treated in the ED from 2013 to 2017 and who had positive urinalyses and urine cultures positive for greater than 50,000 colony-forming unit per milliliter of a single ESBL-producing urinary pathogen. We abstracted details of clinical management and known previous risk factors, including prior neonatal intensive care unit hospitalization stay, prior UTI caused by an ESBL-producing organism, and known urologic abnormalities.

RESULTS

Forty-five UTIs caused by ESBL-producing organisms occurred in 43 patients (mean age of 5.9 months and 59% female)-ESBL Escherichia coli represented the majority (42/45). The incidence of UTIs caused by ESBL-producing organisms ranged from 0.9% to 4.5% during the 5-year study period. The 13 patients (26%) admitted from the ED were significantly younger than discharged patients (1.9 vs 6.7 months, P = 0.016) and more likely to have had prior neonatal intensive care unit hospitalizations (50% vs 15.6%, P = 0.0456). Of the 33 visits (77%) resulting in initial outpatient management, 5 were followed by readmission for parenteral antibiotic treatment. Of those who were readmitted, 40% (n = 2) were afebrile at the time of admission. The remainder (28/33) completed outpatient oral antibiotic courses guided by susceptibilities. Two patients (4%) had negative repeat urine cultures despite in vitro resistance to initial antibiotic coverage.

CONCLUSIONS

Extended spectrum β-lactamase-producing organisms are an increasing cause of UTIs in infants presenting at a pediatric ED, and outpatient management may be reasonable for infants older than 2 months.

From Pathophysiological Hypotheses to Case-Control Study Design: Resistance from Antibiotic Exposure in Community-Onset Infections

Antimicrobial resistance is a global public health concern, at least partly due to the misuse of antibiotics. The increasing prevalence of antibiotic-resistant infections in the community has shifted at-risk populations into the general population. Numerous case-control studies attempt to better understand the link between antibiotic use and antibiotic-resistant community-onset infections. We review the designs of such studies, focusing on community-onset bloodstream and urinary tract infections. We highlight their methodological heterogeneity in the key points related to the antibiotic exposure, the population and design. We show the impact of this heterogeneity on study results, through the example of extended-spectrum β-lactamases producing Enterobacteriaceae. Finally, we emphasize the need for the greater standardization of such studies and discuss how the definition of a pathophysiological hypothesis specific to the bacteria-resistance pair studied is an important prerequisite to clarify the design of future studies.

Antibiotic Resistance in Paediatric Febrile Urinary Tract Infections

Febrile urinary tract infection (UTI) is currently considered the most frequent cause of serious bacterial illness in children in the first 2 years of life. UTI in paediatrics can irreversibly damage the renal parenchyma and lead to chronic renal insufficiency and related problems. To avoid this risk, an early effective antibiotic treatment is essential. Moreover, prompt treatment is mandatory to improve the clinical condition of the patient, prevent bacteraemia, and avoid the risk of bacterial localization in other body sites. However, antibiotic resistance for UTI-related bacterial pathogens continuously increases, making recommendations rapidly outdated and the definition of the best empiric antibiotic therapy more difficult. Variation in pathogen susceptibility to antibiotics is essential for the choice of an effective therapy. Moreover, proper identification of cases at increased risk of difficult-to-treat UTIs can reduce the risk of ineffective therapy. In this review, the problem of emerging antibiotic resistance among pathogens associated with the development of paediatric febrile UTIs and the best potential solutions to ensure the most effective therapy are discussed. Literature analysis showed that the emergence of antibiotic resistance is an unavoidable phenomenon closely correlated with the use of antibiotics themselves. To limit the emergence of resistance, every effort to reduce and rationalise antibiotic consumption must be made. An increased use of antibiotic stewardship can be greatly effective in this regard.

Trends in prevalence of extended-spectrum beta-lactamase-producing Escherichia coli isolated from patients with community- and healthcare-associated bacteriuria: results from 2014 to 2020 in an urban safety-net healthcare system

BACKGROUND

The prevalence of infections caused by extended-spectrum beta-lactamase producing Escherichia coli (ESBL-E. coli) is increasing worldwide, but the setting in which this increase is occurring is not well defined. We compared trends and risk factors for ESBL-E. coli bacteriuria in community vs healthcare settings.

METHODS

We collected electronic health record data on all patients with E. coli isolated from urine cultures in a safety-net public healthcare system from January 2014 to March 2020. All analyses were stratified by healthcare-onset/associated (bacteriuria diagnosed > 48 h after hospital admission or in an individual hospitalized in the past 90 days or in a skilled nursing facility resident, N = 1277) or community-onset bacteriuria (bacteriuria diagnosed < 48 h after hospital admission or in an individual seen in outpatient clinical settings without a hospitalization in the past 90 days, N = 7751). We estimated marginal trends from logistic regressions to evaluate annual change in prevalence of ESBL-E. coli bacteriuria among all bacteriuria. We evaluated risk factors using logistic regression models.

RESULTS

ESBL-E. coli prevalence increased in both community-onset (0.91% per year, 95% CI 0.56%, 1.26%) and healthcare-onset/associated (2.31% per year, CI 1.01%, 3.62%) bacteriuria. In multivariate analyses, age > 65 (RR 1.88, CI 1.17, 3.05), male gender (RR 2.12, CI 1.65, 2.73), and Latinx race/ethnicity (RR 1.52, CI 0.99, 2.33) were associated with community-onset ESBL-E. coli. Only male gender (RR 1.53, CI 1.03, 2.26) was associated with healthcare-onset/associated ESBL-E. coli.

CONCLUSIONS

ESBL-E. coli bacteriuria frequency increased at a faster rate in healthcare-associated settings than in the community between 2014 and 2020. Male gender was associated with ESBL-E. coli bacteriuria in both settings, but additional risks-age > 65 and Latinx race/ethnicity-were observed only in the community.

Antimicrobial resistance and ESBL profile of Uropathogens among pregnant women at Edna Adan Hospital, Hargeisa, Somaliland

BACKGROUND

The emergence and spread of antimicrobial resistance (AMR) among uropathogens is increasing, especially in resource limited settings due to a number of reasons. The production of Extended Spectrum β-Lactamase (ESBL) by some strains of E. coli and methicillin resistant Staphylococcus species, limits the choice of antimicrobials in the treatment of urinary tract infection (UTI) globally. However, little is known about the type of uropathogenes and their current AMR profile among pregnant women in Hargeisa, Somaliland.

METHODS

Clean-catch mid-stream urine samples were collected and processed for bacteriological culture and antimicrobial sensitivity testing (AST). Ceftazidime (30µg) and Cefotaxime (30µg) disks were used for ESBL screening as per CLSI guideline and each ESBL screening positive isolate were phenotypically confirmed by a combination disk test.

RESULTS

Among 376 study participants, 79 (21.0%) had significant bacteriuria (SBU). Majority at 58(73.4%) of the isolates were Gram-negative. The most predominant isolate was E.coli, 36(45.6%) followed by K. pneumonea 16(20.3%) and S. aureus at 9(11.4 %). The proportion of ESBL producing isolates was 25(32.9%). Gram-negatives showed high level resistance to ampicillin, amoxicillin, cefotaxime, and cephalexin at 87%, 85%, 57%, and 52%, respectively. Previous history of UTI, monthly income, educational status and having dysuria were significantly associated with SBU (p<0.05).

CONCLUSION

Relatively high prevalence of uropathogens and an increased level of drug resistance were documented. Therefore, continued surveillance on the type of uropathogens and their AMR pattern is needed to ensure appropriate recommendations for the rational empirical treatment of UTI and for policy input.

Assessment of infections rate due to community-acquired Methicillin-resistant Staphylococcus aureus and evaluation of risk factors in the paediatric population

AIM

We aimed at assessing the frequency of Community-acquired Methicillin-resistant Staphylococcus aureus (CA-MRSA) infections, identifying its risk factors and evaluating resistance patterns of Staphylococcus aureus to various antibiotics in order to recommend the optimal empirical treatment for suspected Staphylococcus aureus infections.

METHODS

We reviewed the medical records of children who were treated at Shaare Zedek medical centre, located in Jerusalem, Israel, over the years 2008-2019 and had a positive culture for Staphylococcus aureus. Patients with CA-MRSA infections were compared with Methicillin-susceptible Staphylococcus aureus (CA-MSSA) infections.

RESULTS

In this study, 620 paediatric patients were included. The number of children in the CA-MRSA study group was 124, while the MSSA control group consisted of 496 children. Risk factors for CA-MRSA infections included young age (1-5 years), female sex, Arab ethnicity and residence in East Jerusalem. The incidence of CA-MRSA increased over the past decade, with an average of 11.2%. An increase in MSSA resistance to clindamycin was noted while Trimethoprim-Sulphamethoxazole resistance remained low.

CONCLUSION

The incidence of CA-MRSA in Jerusalem was rising, along with changes in resistance patterns of both MSSA and MRSA to various antibiotic agents. In order to optimise empirical treatment for suspected staphylococcal infection, continued monitoring of CA-MRSA prevalence and resistance rates is essential.

Resistance to antibacterial therapy in pediatric febrile urinary tract infections-a single-center analysis

BACKGROUND

Febrile urinary tract infections (UTIs) are common serious bacterial infections in childhood and require early diagnosis and antibacterial therapy. However, considerable uncertainty exists regarding the optimal antibacterial agent for primary treatment of pediatric UTIs. Additionally, patterns of susceptibility and resistance change over time and microbiological in vitro resistance is not necessarily associated with treatment failure. Here, we analyzed uropathogens, their resistance patterns, and response to antibacterial treatment in children with acute pyelonephritis.

METHODS

We used billing codes (international classification of diseases) to identify all inpatients aged 0-18 years with febrile UTIs in a German university tertiary care center from 2009 until 2018. Microbial results were retrieved from the laboratory information system for all children, and treatment regimen and treatment response were analyzed in a subgroup of children.

RESULTS

We identified 907 children with acute pyelonephritis; in 590 cases (65%) an uropathogen was detected. Escherichia coli (60.8%), Enterococcus faecalis (13.2%), Klebsiella pneumoniae (7.0%), Proteus spp. (5.2%), and Pseudomonas aeruginosa (4.2%) were the most common pathogens. 353 of 436 E.coli isolates (81.0%) were susceptible or intermediate to aminopenicillin/β-lactamase-inhibitor (BLI) combinations. We examined 52 cases where E. coli was resistant to initial therapy with aminopenicillin/BLI combinations: Therapy was changed in 35 cases (67%) and left unchanged in 17 cases (33%), and we found no significant differences in C-reactive protein and leucocyte count in blood and urine between both groups after 3 days.

CONCLUSIONS

We present the spectrum of uropathogens and susceptibility test results in pediatric UTIs in a tertiary care center. Our findings suggest a satisfactory response to first-line therapy with aminopenicillin/BLI combinations.

Risk factors for third-generation cephalosporin resistant Enterobacteriaceae in gestational urine cultures: A retrospective cohort study based on centralized electronic health records

Third-generation-cephalosporin resistant Enterobacteriaceae (3GCR-EB) carriage in pregnant women poses challenges for infection control and therapeutic decisions. The factors associated with multidrug resistant Enterobacteriaceae carriage in the gestational period are not well documented. The aim of our study was to identify risk factors associated with 3GCR-EB isolation in gestational urine cultures. The study was designed as retrospective cohort based on centralized electronic health records database. Women delivered in Clalit Health Services hospitals in Israel in 2009–2013 and provided urine culture(s) during pregnancy were included. Multivariable analysis using the Generalized Estimating Equations model was used to assess risk factors for 3GCR-EB isolation in gestational urine cultures. The study included 15,282 pregnant women with urine cultures yielding Enterobacteriaceae (EB). The proportion of 3GCR-EB in EB isolates was 3.9% (n = 603). The following risk factors were associated with 3GCR-EB isolation: multiple hospital admissions during the year before delivery (OR,1.47;95% CI,1.21–1.79), assisted fertilization procedure (OR,1.53; 95% CI,1.12–2.10), Arab ethnicity (OR,1.22; 95% CI,1.03–1.45), multiple antibiotic courses (OR,1.76; 95% CI,1.29–2.40), specifically, cephalosporins (OR,1.56; 95% CI,1.26–1.95), fluoroquinolones (OR,1.34; 95% CI,1.04–1.74), or nitrofurantoin (OR,1.29; 95% CI,1.02–1.64). The risk factors identified by this study for 3GCR-EB in gestation, can be easily generalized for pregnant women in the Israeli population. Moreover, these risk factors, other than ethnicity, are applicable to pregnant women worldwide. The information of previous antibiotic treatments, hospitalization in the last year and assisted fertilization procedure can be easily accessed and used for appropriate infection control practices and antimicrobial therapy.

Urinary tract infection caused by extended-spectrum β-lactamase-producing bacteria: Risk factors and antibiotic resistance

BACKGROUND

The aim of this study was to investigate the risk factors for acquisition of extended spectrum β-lactamase (ESBL)-producing bacteria in community-acquired urinary tract infection (UTI) and to evaluate their antimicrobial resistance.

METHODS

The medical records of hospitalized children were retrospectively evaluated. Children with ESBL-producing bacteria UTI were matched with controls with non-ESBL-producing bacteria UTI of the same age and gender.

RESULTS

A total of 243 patients with community-acquired UTI in a 5 year period were evaluated, of whom 46% had UTI caused by ESBL bacteria. Seventy-seven cases were matched with 77 controls. There were no significant differences in the clinical presentation between the two groups apart from a longer hospital stay in the ESBL group (9.1 ± 5.5 days vs 8.0 ± 4.4 days, P = 0.013). Significant potential risk factors for ESBL-UTI were previous use of antibiotics in the last 3 months, previous hospitalization in the last 3 months, history of recurrent UTI, and presence of renal anomalies. On logistic regression analysis, history of previous hospitalization in the last 3 months (OR, 3.83; 95%CI: 1.49-9.84) was identified as an independent significant risk factor for ESBL-UTI. There was a significantly higher resistance to amoxicillin-clavulanate, amikacin, gentamycin and quinolones in the ESBL group compared with the control group.

CONCLUSION

Recognizing the risk factors for ESBL-UTI helps to identify the high-risk cases and enables proper management.

The use of nitrofurantoin for children with acute cystitis caused by extended-spectrum Β-lactamase-producing Escherichia coli

BACKGROUND

Acute cystitis in children caused by extended-spectrum β-lactamase (ESBL)-producing Escherichia coli (E. coli) is on the rise. Treatment of these is usually parenteral treatment. The aim of this study was to investigate the clinical and microbiological efficacy of oral nitrofurantoin treatment in children with lower urinary tract infection (UTI) caused by ESBL-producing E. coli.

METHODS

Fifty children with lower UTI due to ESBL-producing E. coli were prospectively studied. Demographic data, clinical condition, laboratory values, treatment regimens, and complications of the patients were recorded. Urine samples were obtained by transurethral catheterization or clean catch; urine bags were not used for specimen collection for culture. Patients with lower UTI due to ESBL-producing E. coli and found to be susceptible to nitrofurantoin were given oral nitrofurantoin. Patients were re-evaluated 3-4 days after the end of treatment. Renal scintigraphy was performed 1-3 months after the end of treatment.

RESULTS

A total of 50 pediatric patients (48 females and 2 males) were enrolled into study. The mean age was 7.5 ± 3.96 years (range, 1-17 years). The duration of nitrofurantoin treatment was 10 days. Bacteriological response was observed in 49 of 50 patients (98%). No patient had symptoms after treatment. No significant side-effect was observed in any of the patients. All patients had normal serum creatinine values. Renal scintigraphic study, which was performed in all patients 1-3 months after completion of treatment, demonstrated the non-scarring in 48 of 50 patients (96%).

CONCLUSIONS

UTIs due to ESBL-producing E. coli are a serious problem because of the bacteria's multidrug antibiotic resistance pattern. This study suggests that oral nitrofurantoin treatment could be a good alternative for lower UTI caused by ESBL-producing E. coli in pediatric patients.

Frequency of infections caused by ESBL-producing bacteria in a pediatric ward - single-center five-year observation

INTRODUCTION

Infections caused by Enterobacteriaceae producing extended-spectrum β-lactamases (ESBLs) are a serious therapeutic and clinical problem. An increasing role of ESBL(+) pathogens is observed in both community- and hospital-acquired infections. The aim of the study was to assess the incidence and the risk factors for ESBL(+) bacteria infection in a pediatric ward during a 5-year period.

MATERIAL AND METHODS

The medical documentation data of patients hospitalized in the Department of Pediatrics, Pediatric Nephrology and Allergology between 2011 and 2015 were subjected to a retrospective analysis. Cases of ESBL(+) bacterial infections were analyzed in detail.

RESULTS

0.57% (46) of all the hospitalizations (8015) during the 5-year observation period in our department were caused by ESBL (+) pathogens. It constituted 8.5% of all positive microbiological cultures obtained. The analysis revealed an increasing trend in the number of ESBL (+) infections throughout the observed period. 43.5% of patients were only asymptomatic carriers. In 71.7% urinary tract structural and functional abnormalities were present. 76.1% of patients had been hospitalized previously and 60.9% had undergone urinary tract invasive procedures.

CONCLUSIONS

The results confirm the rising trend of ESBL (+) infections during the observed period. ESBL (+) bacteria were isolated primarily in previously hospitalized children with particular reference to urinary tract invasive procedures during hospitalizations. Moreover, the study showed that patients with urogenital disorders and non-urinary chronic diseases are more susceptible to these priority pathogen infections.

Third-generation cephalosporin-resistant urinary tract infections in children presenting to the paediatric emergency department

Background

The incidence of antibiotic-resistant urinary tract infections (UTIs) in children is increasing. The purpose of this study was to describe the incidence, clinical characteristics, and risk factors for third-generation cephalosporin-resistant UTIs presenting to the paediatric emergency department (ED).

Methods

This was a retrospective cohort study conducted at British Columbia Children's Hospital. Children aged 0 to 18 years old presenting to the ED between July 1, 2013 and June 30, 2014 and were found to have UTI due to Enterobacteriaceae and Pseudomonas species were included. Patient demographics, clinical features, laboratory findings, and outcomes were compared using standard statistical analyses. Risk factors for resistant UTIs were analyzed using multiple logistic regression analysis.

Results

There were 294 eligible patients. The median age was 27.4 months. A third-generation cephalosporin-resistant organism was identified in 36 patients (12%). Patients with resistant UTI had lower rates of appropriate empiric antibiotic therapy (25% versus 95.3%, P<0.05), higher rates of hospitalization (38.9% versus 21.3%, P<0.05), higher rates of undergoing a voiding cystourethrogram (19.4% versus 5.0%, P<0.05), and higher rates of UTI recurrence within 30 days (13.9% versus 4.7%, P<0.05). In multivariate analysis, recent hospitalization (odds ratio [OR] 4.3, confidence interval [CI] 1.2 to 16) and antibiotic therapy (OR 3.5, CI 1.5 to 8.5) within the previous 30 days were risk factors for resistant UTI.

Conclusions

Third-generation cephalosporin-resistant organisms account for a significant proportion of community-acquired paediatric UTIs. Recent hospitalization and antibiotic use are associated with increased risk of resistant UTI.

Empirical antibiotics for recurrent urinary tract infections in children

The purpose of this study was to compare antibiotic resistance patterns between first urinary tract infection (UTI) and recurrent UTI groups and to obtain information regarding empirical antibiotic selection for treating recurrent UTI. Methods We retrospectively reviewed 148 children treated for UTIs from January 2009 to June 2016. The patients were divided into two groups: first UTI (N = 148) and recurrent UTI (17 patients and 20 episodes). Results In both groups, Escherichia coli was the most frequent causative organism, accounting for 89.9% and 75.0% in the first and recurrent UTI groups, respectively. When E. coli or Klebsiella pneumoniae was the causative organism, extended-spectrum β-lactamase (ESBL)-producing organisms were more frequent in the recurrent UTI group (17.6%) than in the first UTI group (14.0%); however, this difference was not statistically significant (P = 0.684). Cefotaxime was the most frequently used first-line empirical antibiotic in both groups. In the first UTI and recurrent UTI groups, 7.4% and 15.0% of patients were treated with intravenous antibiotics as definitive therapy, respectively (P = 0.250). Fifteen out of 17 patients having a second UTI had different causative organisms or antibiotic susceptibility patterns compared to their previous episode. Conclusions Escherichia coli was the most frequent causative organism in the recurrent UTI group. There were no differences in the proportion of ESBL-producing organisms between the first UTI and recurrent UTI groups. Therefore, when a UTI recurs in children, the antibiotics effective on the most common causative organism might be administered as empirical antibiotics.

Febrile urinary-tract infection due to extended-spectrum beta-lactamase-producing Enterobacteriaceae in children: A French prospective multicenter study

Objectives

To assess the management of febrile urinary-tract infection (FUTIs) due to extended-spectrum β-lactamase–producing Enterobacteriaceae (ESBL-E) in children, the Pediatric Infectious Diseases Group of the French Pediatric Society set up an active surveillance network in pediatric centers across France in 2014.

Materials and methods

We prospectively analysed data from 2014 to 2016 for all children < 18 years old who received antibiotic treatment for FUTI due to ESBL-E in 24 pediatric centers. Baseline demographic, clinical features, microbiological data and antimicrobials prescribed were collected.

Results

301 children were enrolled in this study. The median age was 1 year (IQR 0.02–17.9) and 44.5% were male. These infections occurred in children with history of UTIs (27.3%) and urinary malformations (32.6%). Recent antibiotic use was the main associated factor for FUTIs due to ESBL-E, followed by a previous hospitalization and travel history. Before drug susceptibility testing (DST), third-generation cephalosporins (3GC) PO/IV were the most-prescribed antibiotics (75.5%). Only 13% and 24% of children received amikacine alone for empirical or definitive therapy, respectively, whereas 88.7% of children had isolates susceptible to amikacin. In all, 23.2% of children received carbapenems in empirical and/or definitive therapy. Cotrimoxazole (24.5%), ciprofloxacin (15.6%) and non-orthodox clavulanate–cefixime combination (31.3%) were the most frequently prescribed oral options after obtaining the DST. The time to apyrexia and length of hospital stay did not differ with or without effective empirical therapy.

Conclusions

We believe that amikacin should increasingly take on a key role in the choice of definitive therapy of FUTI due to ESBL-E in children by avoiding the use of carbapenems.

Once-daily intramuscular amikacin for outpatient treatment of lower urinary tract infections caused by extended-spectrum β-lactamase-producing Escherichia coli in children

Background

The rise in community-acquired urinary tract infections (UTIs) with extended-spectrum β-lactamase (ESBL)-producing Escherichia coli strains raises the question of how to treat these infections effectively in pediatric outpatients. Amikacin has shown promising in vitro activity against ESBL-producing urinary isolates of E. coli; however, clinical data are limited.

Objective

To investigate the clinical and microbiological outcomes of community-acquired lower UTIs caused by ESBL-producing E. coli treated with outpatient amikacin in children.

Materials and methods

A retrospective cohort study was performed on pediatric patients aged ≥2 to 18 years treated as outpatients with intramuscular amikacin (given at a dose of 15 mg/kg/day once daily) for community-acquired lower UTIs caused by ESBL-producing E. coli, between January 2015 and December 2016.

Results

A total of 53 pediatric patients (38 females) were enrolled in this study. The median age was 4.7 years (range 3–12 years). All E. coli isolates were susceptible to amikacin with minimum inhibitory concentrations of ≤4 mg/L. The median duration of amikacin treatment was 6 days (range 3–7 days). Favorable clinical and bacteriological responses were observed in 51 of 53 (96%) patients. Development of resistance during treatment with amikacin was seen in only 1 patient (2%), who failed to respond to amikacin treatment and developed acute pyelonephritis with bacteremia. Relapsed lower UTI after initial treatment response occurred in 1 patient (2%) 2 weeks after completion of amikacin treatment. All patients had normal serum creatinine values at baseline, and no significant nephrotoxicity or ototoxicity was observed in any of the patients.

Conclusion

Our study suggests that once-daily intramuscular amikacin could be an alternative option for outpatient treatment of community-acquired lower UTIs caused by amikacin-susceptible ESBL-producing E. coli in pediatric patients with normal renal function, when there are no suitable oral antibiotics.

Antibiotic Prophylaxis Is Associated with Subsequent Resistant Infections in Children with an Initial Extended-Spectrum-Cephalosporin-Resistant Enterobacteriaceae Infection

The objective of this study was to assess the association between previous antibiotic use, particularly long-term prophylaxis, and the occurrence of subsequent resistant infections in children with index infections due to extended-spectrum-cephalosporin-resistant Enterobacteriaceae We also investigated the concordance of the index and subsequent isolates. Extended-spectrum-cephalosporin-resistant Escherichia coli and Klebsiella spp. isolated from normally sterile sites of patients aged <22 years were collected along with associated clinical data from four freestanding pediatric centers. Subsequent isolates were categorized as concordant if the species, resistance determinants, and fumC-fimH (E. coli) or tonB (Klebsiella pneumoniae) type were identical to those of the index isolate. In total, 323 patients had 396 resistant isolates; 45 (14%) patients had ≥1 subsequent resistant infection, totaling 73 subsequent resistant isolates. The median time between the index and first subsequent infections was 123 (interquartile range, 43 to 225) days. In multivariable Cox proportional hazards analyses, patients were 2.07 times as likely to have a subsequent resistant infection (95% confidence interval, 1.11 to 3.87) if they received prophylaxis in the 30 days prior to the index infection. In 26 (58%) patients, all subsequent isolates were concordant with their index isolate, and 7 (16%) additional patients had at least 1 concordant subsequent isolate. In 12 of 17 (71%) patients with E. coli sequence type 131 (ST131)-associated type 40-30, all subsequent isolates were concordant. Subsequent extended-spectrum-cephalosporin-resistant infections are relatively frequent and are most commonly due to bacterial strains concordant with the index isolate. Further study is needed to assess the role prophylaxis plays in these resistant infections.

Childhood urinary tract infection caused by extended-spectrum β-lactamase-producing bacteria: Risk factors and empiric therapy

BACKGROUND

This study investigated risk factors of childhood urinary tract infection (UTI) associated with extended-spectrum β-lactamase (ESBL)-producing bacteria (ESBL-positive UTI) and evaluated antimicrobial resistance as well as empiric treatment of childhood UTI.

METHODS

The records of children with positive urine culture between 1 January 2008 and 31 December 2012 were evaluated. Patients with positive urine culture for ESBL-producing bacteria were defined as the ESBL-positive group, whereas patients of the same gender and similar age with positive urine culture for non-ESBL-producing bacteria were defined as the ESBL-negative group. Each ESBL-positive patient was matched with two ESBL-negative patients.

RESULTS

The ESBL-positive and negative groups consisted of 154 and 308 patients, respectively. Potential risk factors for ESBL-positive UTI were identified as presence of underlying disease, clean intermittent catheterization (CIC), hospitalization, use of any antibiotic and history of infection in the last 3 months (P < 0.05). On logistic regression analysis, CIC, hospitalization and history of infection in the last 3 months were identified as independent risk factors. In the present study, 324 of 462 patients had empiric therapy. Empiric therapy was inappropriate in 90.3% of the ESBL-positive group and in 4.5% of the ESBL-negative group. Resistance to nitrofurantoin was similar between groups (5.1% vs 1.2%, P = 0.072); resistance to amikacin was low in the ESBL-positive group (2.6%) and there was no resistance in the ESBL-negative group.

CONCLUSIONS

Clean intermittent catheterization, hospitalization and history of infection in the last 3 months should be considered as risk factors for ESBL-positive UTI. The combination of ampicillin plus amikacin should be taken into consideration for empiric therapy in patients with acute pyelonephritis who have the risk factors for ESBL-positive UTI. Nitrofurantoin seems to be a logical choice for the empiric therapy of cystitis.

[Profile of bacterial resistance in pediatric urinary tract infections in 2014]

In pediatric units, bacteria-producing extended-spectrum-betalactamase (ESBL) have an increasing prevalence among bacteria causing febrile urinary tract infections (UTIs). The purpose of this study was to evaluate the epidemiology of bacteria resistance patterns observed in UTIs, in order to assess the current antibiotic treatment protocols. This study is based upon a single-center retrospective chart review of the cytobacteriological urine cultures performed in UTIs between 1 January and 31 December 2014, in the medical pediatric unit of the Caen University Hospital. Out of the total of 219 cases of UTI, 26.9% were recurrences of UTI, 18.3% were infections in infants less than 3 months old, 21% of the patients suffered from underlying uropathy, and 16.4% of the patients had recently been exposed to antibiotics. In 80.3% of the cases, Escherichia coli was found, while Enterococcus faecalis was found in 5.6%. The antibiograms proved that 33.5% of the bacteria were sensitive. Half of E. coli were resistant to ampicillin, 4.9% to cefixime, 4.9% to ceftriaxone, 1.1% to gentamicin, and 27.8% to trimethoprim-sulfamethoxazole. Nine E. coli and one Enterobacter cloacae produced ESBL, accounting for 4.6% of the UTIs. We did not find any bacteria-producing high-level cephalosporinase. Cefixime resistance was statistically linked to ongoing antibiotic treatment (OR=5.98; 95% CI [1.44; 24.91], P=0.014) and underlying uropathy (OR=6.24; 95% CI [1.47; 26.42], P=0.013). Ceftriaxone resistance was statistically related to ongoing antibiotic treatment (OR=6.93; 95% CI [1.45; 33.13], P=0.015). These results argue in favor of maintaining intravenous ceftriaxone for probabilistic ambulatory treatment. However, in case of hospitalization, cefotaxime can replace ceftriaxone, due to its lower ecological impact. Moreover, it is necessary to continue monitoring bacterial resistance and regularly review our treatment protocols.

Extended-spectrum β-lactamase-producing bacteria caused less than 5% of urinary tract infections in a paediatric emergency centre

AIM

The last decade has seen a significant increase in extended-spectrum β-lactamase (ESBL) secreting organisms responsible for paediatric urinary tract infections (UTIs), particularly in community-acquired infections. These expose patients to the risks of antibiotic treatment failure and renal scarring. This prospective study examined the prevalence and risk factors of febrile ESBL UTIs and their treatment in the paediatric emergency department of a university hospital.

METHODS

In this prospective observational study, all children from 0 to 16 years of age with febrile UTIs were included from May 2012 to April 2013. Cases with and without ESBL involvement were compared.

RESULTS

Of the 474 diagnosed febrile UTIs, 22 (4.6%) with a 95% confidence interval (95% CI) of 2.9-6.9 were due to an ESBL-producing organism. Escherichia coli was found in 85% of cases. Significant odds ratios (OR) for ESBL urinary tract infections were prior hospitalisation (OR 4.1, 95% CI 1.6-10.8), urinary tract abnormalities (OR 3.9, 95% CI 1.5-10.2) and previous antibiotic treatment (OR 3.1, 95% CI 1.2-8.8). All ESBL urinary tract infections had positive outcomes.

CONCLUSION

The prevalence of febrile ESBL urinary tract infections was less than 5% in a paediatric emergency department. This low rate was not high enough to justify changing our guidelines.

Prevalence of ESBL-producing Enterobacteriaceae in paediatric urinary tract infections: A systematic review and meta-analysis

OBJECTIVES

We aimed to evaluate the prevalence of paediatric urinary tract infections (UTIs) caused by extended spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE), identify predisposing factors and examine their effect on the length of hospital stay (LOS).

METHODS

For this systematic review and meta-analysis, we searched the PubMed and EMBASE databases for studies that provide data on the rate of ESBL-PE among paediatric UTIs.

RESULTS

Out of 1828 non-duplicate citations, 16 studies reporting a total of 7374 cases of UTI were included. The prevalence of ESBL-PE was 14% [(95%CI 8, 21)]. Vesicoureteral reflux (VUR) [OR = 2.79, (95%CI 1.39, 5.58)], history of UTI [OR = 2.89 (95%CI 1.78, 4.68)] and recent antibiotic use [OR = 3.92, (95%CI 1.76, 8.7)] were identified as risk factors. The LOS was significantly longer among children infected with ESBL-PE, compared to those infected with other uropathogens. [SMD = 0.88, (95%CI 0.40, 1.35)].

CONCLUSIONS

In the paediatric population, 1 out of 7 UTIs are caused by ESBL-PE. Patients with VUR, previous UTI or recent antibiotic use constitute a high risk group and these pathogens are associated with increased LOS. The significant incidence of ESBL-PE in this population should be taken into consideration in the development of empiric treatment protocols and antibiotic stewardship programmes, especially in high-prevalence areas.

A Clinical Decision Tree to Predict Whether a Bacteremic Patient Is Infected With an Extended-Spectrum β-Lactamase-Producing Organism

BACKGROUND

Timely identification of extended-spectrum β-lactamase (ESBL) bacteremia can improve clinical outcomes while minimizing unnecessary use of broad-spectrum antibiotics, including carbapenems. However, most clinical microbiology laboratories currently require at least 24 additional hours from the time of microbial genus and species identification to confirm ESBL production. Our objective was to develop a user-friendly decision tree to predict which organisms are ESBL producing, to guide appropriate antibiotic therapy.

METHODS

We included patients ≥18 years of age with bacteremia due to Escherichia coli or Klebsiella species from October 2008 to March 2015 at Johns Hopkins Hospital. Isolates with ceftriaxone minimum inhibitory concentrations ≥2 µg/mL underwent ESBL confirmatory testing. Recursive partitioning was used to generate a decision tree to determine the likelihood that a bacteremic patient was infected with an ESBL producer. Discrimination of the original and cross-validated models was evaluated using receiver operating characteristic curves and by calculation of C-statistics.

RESULTS

A total of 1288 patients with bacteremia met eligibility criteria. For 194 patients (15%), bacteremia was due to a confirmed ESBL producer. The final classification tree for predicting ESBL-positive bacteremia included 5 predictors: history of ESBL colonization/infection, chronic indwelling vascular hardware, age ≥43 years, recent hospitalization in an ESBL high-burden region, and ≥6 days of antibiotic exposure in the prior 6 months. The decision tree's positive and negative predictive values were 90.8% and 91.9%, respectively.

CONCLUSIONS

Our findings suggest that a clinical decision tree can be used to estimate a bacteremic patient's likelihood of infection with ESBL-producing bacteria. Recursive partitioning offers a practical, user-friendly approach for addressing important diagnostic questions.

Previous Antibiotic Exposure Increases Risk of Infection with Extended-Spectrum-β-Lactamase- and AmpC-Producing Escherichia coli and Klebsiella pneumoniae in Pediatric Patients

The objective of this study was to determine whether antibiotic exposure is associated with extended-spectrum-beta-lactamase- or AmpC-producing Escherichia coli or Klebsiella pneumoniae infections in children. We collected extended-spectrum-beta-lactamase- or AmpC-producing E. coli or K. pneumoniae isolates and same-species susceptible controls from normally sterile sites of patients aged ≤21 years, along with associated clinical data, at four free-standing pediatric centers. After controlling for potential confounders, the relative risk of having an extended-spectrum-beta-lactamase-producing isolate rather than a susceptible isolate was 2.2 times higher (95% confidence interval [CI], 1.49 to 3.35) among those with antibiotic exposure in the 30 days prior to infection than in those with no antibiotic exposure. The results were similar when analyses were limited to exposure to third-generation cephalosporins, other broad-spectrum beta-lactams, or trimethoprim-sulfamethoxazole. Conversely, the relative risk of having an AmpC-producing versus a susceptible isolate was not significantly elevated with any antibiotic exposure in the 30 days prior to infection (adjusted relative risk ratio, 1.12; 95% CI, 0.65 to 1.91). However, when examining subgroups of antibiotics, the relative risk of having an AmpC-producing isolate was higher for patients with exposure to third-generation cephalosporins (adjusted relative risk ratio, 4.48; 95% CI, 1.75 to 11.43). Dose-response relationships between antibiotic exposure and extended-spectrum-beta-lactamase-producing or AmpC-producing isolates were not demonstrated. These results reinforce the need to study and implement pediatric antimicrobial stewardship strategies, and they indicate that epidemiological studies of third-generation cephalosporin-resistant E. coli and K. pneumoniae isolates should include resistance mechanisms when possible.

Causative pathogens and antibiotic resistance in children hospitalized for urinary tract infection

BACKGROUND

Urinary tract infections (UTI) are one of the most common bacterial infections in children and a major cause of hospitalization. In this study we investigated the clinical characteristics, causative uropathogens; their antibiotic susceptibility and resistance patterns, treatment modalities and efficacy in children hospitalized for UTI in a tertiary care setting.

METHODS

Patients hospitalized for an upper UTI between March 2009 and July 2014 were enrolled. The urine culture-antibiogram results and accompanying urinary tract abnormalities were recorded retrospectively.

RESULTS

A total of 142 patients (104 girls, 73.2%; 38 boys, 26.8%) were enrolled. Mean patient age was 32.6 ± 4.1 months. History of recurrent UTI was present in 45.8% (n = 65), with prior hospitalization in 12.0% (n = 17). Frequency of vesicoureteral reflux was 18.3% (n = 26). Gram-negative enteric microorganisms yielded growth in all culture-positive UTI and the most common microorganism was Escherichia coli (n = 114, 80.3%). Extended spectrum beta-lactamase-producing (ESBL (+)) bacterial strains were detected in 49.3% (n = 70), with third-generation cephalosporin resistance in all and increased duration of hospitalization.

CONCLUSIONS

The prevalence of UTI with ESBL (+) bacterial strains with multi-drug resistance is increasing in the hospitalized pediatric population, therefore rational use of antibiotics is essential.

Community-acquired febrile urinary tract infection caused by extended-spectrum beta-lactamase-producing bacteria in hospitalised infants

INTRODUCTION

Extended-spectrum beta-lactamase (ESBL) producing bacteria are infrequent pathogens of urinary tract infections in children. The objective of our study was to investigate the presence, clinically associated characteristics and risk factors for acquisition of urinary tract infection/acute pyelonephritis (UTI/APN) in hospitalised children <2years old caused by community-acquired ESBL.

METHODS

A case-control study in a second level community hospital in Spain, in which 537 episodes of UTI/APN were investigated in a retrospective study between November 2005 and August 2014. Cases were patients with ESBL strains. For each case, four ESBL-negative controls were selected. A questionnaire with the variables of interest was completed for every patient, and the groups were compared.

RESULTS

ESBL-positive strains were found in 19 (3,5%) cultures. Of these 16 (84%) were Escherichia coli. Vesicoureteral reflux (VUR) of any grade was more frequent in the ESBL group (60 vs. 29%), although without statistical significance. Relapses were more frequent in the ESBL group (42% vs. 18%) (P=.029; OR=3.2; 95%CI: 1.09-9.5). The prevalence of UTI/APN due to ESBL-positive strains increased slightly from 2.7% in the period 2005-2009 to 4.4% in the period 2010-2014.

CONCLUSIONS

ESBL UTI/APN were associated with more frequent relapses. VUR of any grade was twice more frequent in the ESBL group. Piperacillin/tazobactam, fosfomycin and meropenem showed an excellent activity. Aminoglycosides may be a therapeutic option, and in our patients gentamicin was the antibiotic most used.

The Prevalence and Molecular Epidemiology of Multidrug-Resistant Enterobacteriaceae Colonization in a Pediatric Intensive Care Unit

OBJECTIVE

To determine the prevalence and acquisition of extended-spectrum β-lactamases (ESBLs), plasmid-mediated AmpCs (pAmpCs), and carbapenemases ("MDR Enterobacteriaceae") colonizing children admitted to a pediatric intensive care unit (PICU).

DESIGN

Prospective study.

SETTING

40-bed PICU.

METHODS

Admission and weekly thereafter rectal surveillance swabs were collected on all pediatric patients during a 6-month study period. Routine phenotypic identification and antibiotic susceptibility testing were performed. Enterobacteriaceae displaying characteristic resistance profiles underwent further molecular characterization to identify genetic determinants of resistance likely to be transmitted on mobile genetic elements and to evaluate relatedness of strains including DNA microarray, multilocus sequence typing, repetitive sequence-based PCR, and hsp60 sequencing typing.

RESULTS

Evaluating 854 swabs from unique children, the overall prevalence of colonization with an MDR Enterobacteriaceae upon admission to the PICU based on β-lactamase gene identification was 4.3% (n=37), including 2.8% ESBLs (n=24), 1.3% pAmpCs (n=11), and 0.2% carbapenemases (n=2). Among 157 pediatric patients contributing 603 subsequent weekly swabs, 6 children (3.8%) acquired an incident MDR Enterobacteriaceae during their PICU stay. One child acquired a pAmpC (E. coli containing bla DHA) related to an isolate from another patient.

CONCLUSIONS

Approximately 4% of children admitted to a PICU were colonized with MDR Enterobacteriaceae (based on β-lactamase gene identification) and an additional 4% of children who remained in the PICU for at least 1 week acquired 1 of these organisms during their PICU stay. The acquired MDR Enterobacteriaceae were relatively heterogeneous, suggesting that a single source was not responsible for the introduction of these resistance mechanisms into the PICU setting.

Epidemiology and characteristics of urinary tract infections in children and adolescents

Background: Urinary tract infections (UTIs) are among the most common infections in the pediatric population. Over the last two decades, antibiotic resistance is increasing significantly as extended spectrum beta lactamase (ESBL) producing organisms are emerging. The aim of this study is to provide a comprehensive view of the epidemiologic characteristics of UTIs in hospitalized children, examine the risk factors of UTIs caused by ESBL-producing organisms, and determine the resistance patterns in the isolated organisms over the last 10 years.

Methods: Retrospective chart review was conducted at two Lebanese medical centers. Subjects were identified by looking at the following ICD-9 discharge codes: “Urinary tract infection,” “UTI,” “Cystitis,” and/or “Pyelonephritis.” Children less than 18 years of age admitted for UTI between January 1st, 2001 and December 31st, 2011 were included. Cases whose urine culture result did not meet our definition for UTI were excluded. Chi-square, Fisher's exact test, and multivariate logistic regression were used to determine risk factors for ESBL. Linear regression analysis was used to determine resistance patterns.

Results: The study included 675 cases with a median age of 16 months and female predominance of 77.7% (525 cases). Of the 584 cases caused by Escherichia coli or Klebsiella spp, 91 cases (15.5%) were found to be ESBL-producing organisms. Vesico-ureteral reflux and previous antibiotics use were found to be independent risk factors for ESBL-producing E. coli and Klebsiella spp. (p < 0.05). A significant linear increase in resistance to all generations of Cephalosporins (r² = 0.442) and Fluoroquinolones (r² = 0.698) was found.

Conclusion: The recognition of risk factors for infection with ESBL-producing organisms and the observation of increasing overall resistance to antibiotics warrant further studies that might probably lead to new recommendations to guide management of UTIs and antibiotic use in children and adolescents.

The contribution of extended-spectrum β-lactamases to multidrug-resistant infections in children

PURPOSE OF REVIEW

The prevalence of multidrug-resistant (MDR) infections caused by Gram-negative rods (GNRs) such as Escherichia coli and Klebsiella pneumoniae is increasing in large part because of the production of extended-spectrum β-lactamases (ESBLs) that confer resistance to third-generation cephalosporins such as ceftriaxone. This review examines the clinical implication of changes in the epidemiology, diagnostic tools, and reporting criteria for ESBL-GNRs.

RECENT FINDINGS

Pediatric ESBL-GNR infections, once associated only with hospitals, are increasing in the community. The most common risk factor for ESBL-GNR infection is previous antibiotic use. Evidence also exists for prolonged fecal carriage after discharge from neonatal ICUs, leading to community transmission with close contact of known carriers. Controversial changes in the laboratory criteria for GNR cephalosporin resistance have also contributed to the increased numbers of reported MDR-GNR infections. Newer diagnostic tools will enable more rapid identification of MDR-GNR infections, leading to earlier implementation of appropriate therapy.

SUMMARY

ESBL-GNR infections are no longer limited to ICUs and are now being identified in children presenting from the community. Appropriate antibiotic prescribing practices are critical to limit the spread of ESBL-GNRs, and pediatricians must prepare to identify and treat these challenging infections.

Extended-spectrum β-lactamase-producing Enterobacteriaceae in children: old foe, emerging threat

Extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae present an ever-growing burden in the hospital and community settings, across all ages and demographics. Infections due to ESBL-containing pathogens continue to be associated with significant morbidity and mortality worldwide. With widespread empiric broad-spectrum β-lactam use creating selective pressure, and the resultant emergence of stable, rapidly proliferating ESBL-producing clones with continued horizontal gene transfer across genera, addressing this issue remains imperative. Although well characterized in adults, the epidemiology, risk factors, outcomes, therapies, and control measures for ESBL-producing bacteria are less appreciated in children. This analysis provides a brief summary of ESBL-producing Enterobacteriaceae in children, with a focus on recent clinical and molecular data regarding colonization and infection in nonoutbreak settings.

Effect of ceftriaxone on the outcome of murine pyelonephritis caused by extended-spectrum-β-lactamase-producing Escherichia coli

Urinary tract infections (UTIs) due to extended-spectrum-β-lactamase (ESBL)-producing Enterobacteriaceae in children are becoming more frequent, and they are commonly treated initially with a second- or third-generation cephalosporin. We developed a murine model of ascending UTI caused by ESBL-producing Escherichia coli. Using this model, we investigated the renal bacterial burden, interleukin-6 (IL-6) expression, and histopathological alterations caused by ESBL- and non-ESBL-producing bacteria after 1, 2, or 6 days with or without ceftriaxone therapy. The renal bacterial burden, IL-6 concentration, and histological inflammatory lesions were not significantly different between mice infected with ESBL- and non-ESBL-producing bacteria without treatment at any of the time points examined. Following ceftriaxone administration, the bacterial burden was eliminated in the kidneys of mice infected with ESBL- and non-ESBL-producing bacteria on the 6th postinfection day. The histological analysis demonstrated that among mice treated with ceftriaxone, those infected with ESBL-producing bacteria had more profound renal alterations than those infected with non-ESBL-producing bacteria on the 6th day (P < 0.001). In comparison, microbiological outcomes did not differ significantly between mice infected with ESBL- and non-ESBL-producing bacteria at any of the time points examined. The effectiveness of ceftriaxone in mice with UTIs due to ESBL-producing E. coli may have therapeutic implications; it is, however, hampered by limited activity on the histopathological lesions, a finding that needs further investigation.