Trends and predictors of antimicrobial resistance among patients with urinary tract infections at a tertiary hospital facility in Alexandria, Egypt: a retrospective record-based classification and regression tree analysis

BACKGROUND

The incidence of Antimicrobial Resistance (AMR) in uropathogens varies between countries and over time. We aim to study the patterns and potential predictors of AMR among patients with UTIs admitted to the Urology Department at Alexandria University Hospital.

METHODS

An observational retrospective record-based study was conducted on all patients admitted to the Urology department from October 2018 to October 2020. Data collected from patients' records included: demographic data, diagnosis on admission, history of chronic diseases, duration of hospital stay, insertion of a urinary catheter, duration of the catheter in days, history of the use of antibiotics in the previous three months, and history of urinary tract operations. If UTI was documented, we abstracted data about urine culture, use of antibiotics, results of urine cultures, type of organism isolated, and sensitivity to antibiotics. We conducted a multivariable logistic regression model. We performed Classification and Regression Tree Analysis (CART) for predicting risk factors associated with drug resistance among patients with UTI. Data were analyzed using SPSS statistical package, Version 28.0, and R software (2022).

RESULTS

This study encompassed 469 patients with UTIs. The most commonly isolated bacterium was Escherichia coli, followed by Klebsiella pneumoniae. Multidrug resistance (MDR) was found in 67.7% (149/220) of patients with hospital-acquired UTIs and in 49.4% (83/168) of patients with community-acquired UTIs. Risk factors independently associated with antimicrobial resistance according to logistic regression analysis were the use of antibiotics within three months (AOR = 5.2, 95% CI 2.19-12.31), hospital-acquired UTI (AOR = 5.7, 95% CI 3.06-10.76), diabetes mellitus (AOR = 3.8, 95% CI 1.24-11.84), age over 60 years (AOR = 2.9, 95% CI 1.27-6.72), and recurrent UTI (AOR = 2.6, 95% CI 1.08-6.20). Classification and regression tree (CART) analysis revealed that antibiotic use in the previous three months was the most significant predictor for developing drug resistance.

CONCLUSION

The study concluded a high level of antimicrobial resistance as well as significant MDR predictors among hospitalized patients with UTIs. It is vital to assess resistance patterns in our hospitals frequently to improve rational antibiotic treatment as well as to sustain antimicrobial stewardship programs and a rational strategy in the use of antibiotics. Empirical therapy for UTI treatment should be tailored to the potential pathogens' susceptibility to ensure optimal treatment. Strategic antibiotic use is essential to prevent further AMR increases. Further research should focus on suggesting new biological systems or designed drugs to combat the resistance of UTI pathogens.

Infection detection in faces: Children's development of pathogen avoidance

This study examined the development of children's avoidance and recognition of sickness using face photos from people with natural, acute, contagious illness. In a U.S. sample of fifty-seven 4- to 5-year-olds (46% male, 70% White), fifty-two 8- to 9-year-olds (26% male, 62% White), and 51 adults (59% male, 61% White), children and adults avoided and recognized sick faces (ds ranged from 0.38 to 2.26). Both avoidance and recognition improved with age. Interestingly, 4- to 5-year-olds' avoidance of sick faces positively correlated with their recognition, suggesting stable individual differences in these emerging skills. Together, these findings are consistent with a hypothesized immature but functioning and flexible behavioral immune system emerging early in development. Characterizing children's sickness perception may help design interventions to improve health.

Longitudinal metagenomic study reveals the dynamics of fecal antibiotic resistome in pigs throughout the lifetime

BACKGROUND

The dissemination of antibiotic resistance genes (ARGs) poses a substantial threat to environmental safety and human health. Herein, we present a longitudinal paired study across the swine lifetime from birth to market, coupled with metagenomic sequencing to explore the dynamics of ARGs and their health risk in the swine fecal microbiome.

RESULTS

We systematically characterized the composition and distribution of ARGs among the different growth stages. In total, 829 ARG subtypes belonging to 21 different ARG types were detected, in which tetracycline, aminoglycoside, and MLS were the most abundant types. Indeed, 134 core ARG subtypes were shared in all stages and displayed a growth stage-associated pattern. Furthermore, the correlation between ARGs, gut microbiota and mobile genetic elements (MGEs) revealed Escherichia coli represented the main carrier of ARGs. We also found that in most cases, the dominant ARGs could be transmitted to progeny piglets, suggesting the potential ARGs generation transmission. Finally, the evaluation of the antibiotic resistance threats provides us some early warning of those high health risk ARGs.

CONCLUSIONS

Collectively, this relatively more comprehensive study provides a primary overview of ARG profile in swine microbiome across the lifetime and highlights the health risk and the intergenerational spread of ARGs in pig farm.

Antibiotic resistance in elderly patients: Comparison of Enterobacterales causing urinary tract infections between community, nursing homes and hospital settings

OBJECTIVE

The objective was to compare the prevalence of antibiotic resistance of, Escherichia coli, Proteus mirabilis, and Klebsiella pneumoniae in elderly patients in, three sectors: community, nursing homes, and hospital settings.

MATERIAL AND METHODS

This study was a retrospective observational study conducted in, Bourgogne Franche-Comté (France). We collected positive urine samples from, patients over 75 years of age from six private laboratories.

RESULTS

Antibiotic resistance rate for E. coli in nursing homes was close to that of the, ommunity setting. Conversely, resistance of K. pneumoniae in nursing homes was, close to hospital settings. No difference in resistance of P. mirabilis was observed, between the three healthcare sectors.

CONCLUSIONS

Patients living in nursing homes should not be considered more at risk of, infection by multi-drug resistant E. coli than patients living in community setting. Screening of multi-drug resistant K. pneumoniae could be of interest for nursing home, patients.

Age-dependent virulence of human pathogens

Host age is often evoked as an intrinsic factor aggravating the outcome of host-pathogen interactions. However, the shape of the relationship between age and infection-induced mortality might differ among pathogens, with specific clinical and ecological traits making some pathogens more likely to exert higher mortality in older hosts. Here, we used a large dataset on age-specific case fatality rate (CFR) of 28 human infectious diseases to investigate i) whether age is consistently associated to increased CFR, ii) whether pathogen characteristics might explain higher CFR in older adults. We found that, for most of the infectious diseases considered here, CFR slightly decreased during the first years of life and then steeply increased in older adults. Pathogens inducing diseases with long-lasting symptoms had the steepest increase of age-dependent CFR. Similarly, bacterial diseases and emerging viruses were associated with increasing mortality risk in the oldest age classes. On the contrary, we did not find evidence suggesting that systemic infections have steeper slopes between CFR and age; similarly, the relationship between age and CFR did not differ according to the pathogen transmission mode. Overall, our analysis shows that age is a key trait affecting infection-induced mortality rate in humans, and that the extent of the aggravating effect on older adults depends on some key traits, such as the duration of illness.

Mortality due to infectious diseases varies tremendously among infectious agents, with some pathogens producing no mortality, and others being often associated with a fatal outcome. Such variability depends on characteristics of the pathogen, the host and the environment where hosts and pathogens interact. Age is one of the main host traits that accounts for differences in infection-induced mortality (with mortality being higher at the extremes of the age spectrum). Here, we used a large dataset on 28 human infectious diseases to explore the clinical and ecological traits that might account for differences in age-specific mortality risk. We found that pathogens producing long-lasting disease symptoms exert the highest mortality risk in the older adults. Similarly, emerging pathogens are also associated with higher mortality risk in the oldest age classes. These results confirm that age is a key trait affecting infection-induced mortality rate in humans, and show that the extent of the aggravating effect in older adults depends on some key traits, such as the duration of illness.

Evaluation of the in vitro activity of ceftaroline, ceftazidime/avibactam and comparator antimicrobial agents against clinical isolates from paediatric patients in Kuwait: ATLAS data 2012-19

OBJECTIVES

To report antimicrobial resistance data for Gram-positive and Gram-negative pathogens isolated from paediatric patients in three hospitals in Kuwait during 2012-19.

METHODS

In vitro activity of antimicrobials against isolates from documented infections was determined using CLSI broth microdilution method and breakpoints at a central laboratory. Enterobacterales and Pseudomonas aeruginosa isolates were screened for β-lactamases using multiplex PCR assays. Phenotypic determination of resistance in Haemophilus influenzae and Gram-positive isolates was performed using standard methodologies.

RESULTS

Among 515 Enterobacterales isolates, 29.3% were ESBL-positive; susceptibility was highest to amikacin, ceftazidime/avibactam and meropenem (≥97.4%), regardless of ESBL status. CTX-M-15 was identified in 87.1% of ESBL-positive Escherichia coli and 84.2% of ESBL-positive Klebsiella pneumoniae isolates. Of 111 P. aeruginosa isolates, 9.9% were MDR and 12.6% meropenem-resistant (MEM-R). Amikacin and ceftazidime/avibactam had the highest susceptibility rates in the overall group (≥92.8%), with reduced rates among MDR and MEM-R isolates. All 269 MRSA and 180 MSSA isolates were susceptible to daptomycin, linezolid, teicoplanin, tigecycline and vancomycin. All MSSA and 99.3% of MRSA were ceftaroline susceptible. All 168 pneumococcal isolates were susceptible to ceftaroline, linezolid, tigecycline and vancomycin. H. influenzae and Streptococcus pyogenes ceftaroline susceptibility rates were ≥93.3% and ≥95.6%.

CONCLUSIONS

Most isolates of Enterobacterales (including resistant phenotypes) and P. aeruginosa from Kuwait during 2012-19 were susceptible to ceftazidime/avibactam. Ceftaroline was active against most Gram-positive isolates, including resistant phenotypes, and ESBL-negative Enterobacterales. These results indicate that novel antibiotics such as ceftazidime/avibactam and ceftaroline represent valuable treatment options for paediatric infections, including those caused by MDR organisms.

Therapeutic Drug Monitoring of Antibiotics in the Elderly: A Narrative Review

PURPOSE

Antibiotic dosing adaptation in elderly patients is frequently complicated by age-related changes affecting the processes of drug absorption, distribution, metabolism, and/or elimination. These events eventually result in treatment failure and/or development of drug-related toxicity. Therapeutic drug monitoring (TDM) can prevent suboptimal antibiotic exposure in adult patients regardless of age. However, little data are available concerning the specific role of TDM in the elderly.

METHODS

This review is based on a PubMed search of the literature published in the English language. The search involved TDM studies of antibiotics in the elderly performed between 1990 and 2021. Additional studies were identified from the reference lists of the retrieved articles. Studies dealing with population pharmacokinetic modeling were not considered.

RESULTS

Only a few studies, mainly retrospective and with observational design, have specifically dealt with appropriate antibiotic dosing in the elderly based on TDM. Nevertheless, some clinical situations in which the selection of optimal antibiotic dosing in the elderly was successfully guided by TDM were identified.

CONCLUSIONS

Elderly patients are at an increased risk of bacterial infections and inadequate drug dosing compared to younger patients. Therefore, the availability of TDM services can improve the appropriateness of antibiotic prescriptions in this population.

Epidemiology and Antimicrobial Susceptibility of Invasive Bacterial Infections in Children-A Population-Based Study From Norway

OBJECTIVE

To describe epidemiology and antimicrobial susceptibility testing (AST) data of bacteria causing invasive infections in Norwegian children (0-18 years).

METHODS

Population-based observational study using prospectively collected AST data from the Norwegian Surveillance System of Antimicrobial Resistance from 2013 to 2017. We included all clinically relevant bacterial isolates (blood and cerebrospinal fluid), and compared incidence of invasive infections and AST data in isolates from children and adults.

RESULTS

We included 1173 isolates from children and 44,561 isolates from adults. Staphylococcus aureus accounted for 220/477 (46.2%, 95% CI: 41.6-50.7) of all isolates in schoolchildren (6-18 years). Compared with Streptococcus pneumonia isolates from adults (N = 2674), we observed higher nonsusceptibility rates to penicillin in isolates from children (N = 151), 11.9% versus 5.8%, P < 0.01; also higher resistance rates to erythromycin (11.3% vs. 4.9%, P < 0.01), clindamycin (9.3% vs. 3.6%, P < 0.001), and trimethoprim/sulfamethoxazole (17.9% vs. 6.4%, P < 0.001). Compared with Escherichia coli isolates in adults (N = 9073), we found lower rates of ESBL in isolates from children (N = 212), 2.4% versus 6.4%, P < 0.05.

CONCLUSION

The study indicates the importance of microbiologic surveillance strategies in children and highlights the need for pediatric AST data. The high rates of nonsusceptibility to commonly used antibiotics among S. pneumoniae in children and the high burden of invasive S. aureus infections in schoolchildren calls for modifications of Norwegian guidelines.

Changes of antibiotic prescribing pattern and its resistance to E. Coli in South Korea: a 12-year retrospective observational study

In the present study, we investigated the pattern of changes in antibiotic prescription and antimicrobial resistance (AMR) in Escherichia coli in South Korea between 2007 and 2018. We collected data related to antibiotic prescription and AMR in E. coli from the national surveillance system. We used the Mann–Kendall test and Spearman’s correlation to identify the trends of antibiotic prescription and AMR in E. coli and to examine the relationship between them, respectively. Although we noted a significant decreasing trend of ampicillin and gentamicin prescriptions in all medical institutions, we identified a higher level of AMR in long-term care facilities than in other medical institutions. We did not identify a significant positive correlation between ampicillin and gentamicin prescriptions and their resistance in E. coli. However, we found a significant positive correlation between cefotaxime prescription and its resistance in E. coli in hospitals, long-term care facilities, and clinics. Our results strongly suggest that long-term care facilities in South Korea have the potential to sustain AMR epidemics and that more efforts are needed to curb AMR in E. coli. Further epidemiological studies using enhanced AMR surveillance are warranted.

The ongoing challenge of vancomycin-resistant Enterococcus faecium and Enterococcus faecalis in Europe: an epidemiological analysis of bloodstream infections

Vancomycin-resistant enterococci infections are of great public health significance due to limited therapeutic options. We investigated epidemiological trends and risk factors of vancomycin resistance in enterococci isolates from patients with bloodstream infections in the EU/EEA from 2012 to 2018. Routine vancomycin susceptibility data of clinical E. faecium (n = 67,022) and E. faecalis (n = 103,112) blood isolates from the European Antimicrobial Resistance Surveillance Network were analysed using descriptive statistics and multivariable regression analyses. In Europe, proportions of vancomycin-resistant E. faecium (VREFm) increased from 8.1% (95%CI 6.7-9.7%) in 2012 to 19.0% (95%CI 16.8-21.5%) in 2018. Rising VREFm proportions were observed across all European regions, both genders and all age groups except children and adolescents (1-19 years). Adults (20-59 years) and elderly (≥60 years) had an increased likelihood of VREFm compared to children and adolescents (1-19 years) (OR: 1.99 [95%CI 1.42-2.79, p < 0.001] and OR: 1.56 [95%CI 1.09-2.23, p = 0.014], respectively). Inpatients hospital units, including internal medicine and ICUs, were associated with an increased likelihood of VREFm (OR: 2.29 (95%CI 1.58-3.32, p < 0.001) compared to the emergency department which reflects patients with community origin of E. faecium infections. The mean proportion of vancomycin-resistant E. faecalis in Europe was found to be low (1.1% [95%CI 0.9-1.4%]). Local and regional authorities should intensify efforts directed at diagnostic and antimicrobial stewardship for vancomycin and all last resort drugs for the management of VREFm, particularly for hospitalized elderly patients.

The epidemiology of carbapenem-non-susceptible Acinetobacter species in Europe: analysis of EARS-Net data from 2013 to 2017

BACKGROUND

Due to limited therapeutic options and their association with high mortality and morbidity, carbapenem-non-susceptible Acinetobacter spp. (CNA) are of significant public health importance. This study aimed to describe current epidemiological trends of CNA proportions in Europe and to identify factors that are associated with carbapenem non-susceptibility of isolates from patients with invasive Acinetobacter spp. infections.

METHODS

Data from routine carbapenem susceptibility testing of 18,412 invasive clinical Acinetobacter spp. isolates from 30 European countries in 2013-2017 were analysed using descriptive statistical analyses and uni- and multivariable regression analyses. These data were obtained from the European Antimicrobial Resistance Surveillance Network (EARS-Net).

RESULTS

The population-weighted mean proportion of carbapenem-non-susceptible Acinetobacter spp. in Europe is 35.6% (95% confidence interval [CI] 29.7-42.0%). With CNA proportions of 75.5% (95% CI 71.2-79.4%) and 71.5% (95% CI 66.7-75.9%) the burden of CNA is particularly high in Southern and Eastern European regions. In contrast, Northern and Western European regions recorded CNA proportions of 2.8% (95% CI 1.2-6.0%) and 6.3% (95% CI 4.5-8.9%), respectively. Population-weighted mean CNA proportions are especially high in Acinetobacter spp. isolates from intensive care units (54.0% [95% CI 47.6-60.3%]). Male gender, age above 20 years and ICU admission were identified as independent factors associated with an increased likelihood of CNA.

CONCLUSION

The burden of carbapenem-non-susceptible Acinetobacter spp. is particularly high in Southern and Eastern Europe. There is a risk that resistance could spread to other parts of Europe. Therefore, increased efforts in infection control and antibiotic stewardship, particularly in Intensive Care Units, are necessary to combat the spread of CNA in Europe.

The global prevalence of Daptomycin, Tigecycline, Quinupristin/Dalfopristin, and Linezolid-resistant Staphylococcus aureus and coagulase-negative staphylococci strains: a systematic review and meta-analysis

Objective

Methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant coagulase-negative Staphylococcus (MRCoNS) are among the main causes of nosocomial infections, which have caused major problems in recent years due to continuously increasing spread of various antibiotic resistance features. Apparently, vancomycin is still an effective antibiotic for treatment of infections caused by these bacteria but in recent years, additional resistance phenotypes have led to the accelerated introduction of newer agents such as linezolid, tigecycline, daptomycin, and quinupristin/dalfopristin (Q/D). Due to limited data availability on the global rate of resistance to these antibiotics, in the present study, the resistance rates of S. aureus, Methicillin-resistant S. aureus (MRSA), and CoNS to these antibiotics were collected.

Method

Several databases including web of science, EMBASE, and Medline (via PubMed), were searched (September 2018) to identify those studies that address MRSA, and CONS resistance to linezolid, tigecycline, daptomycin, and Q/D around the world.

Result

Most studies that reported resistant staphylococci were from the United States, Canada, and the European continent, while African and Asian countries reported the least resistance to these antibiotics. Our results showed that linezolid had the best inhibitory effect on S. aureus. Although resistances to this antibiotic have been reported from different countries, however, due to the high volume of the samples and the low number of resistance, in terms of statistical analyzes, the resistance to this antibiotic is zero. Moreover, linezolid, daptomycin and tigecycline effectively (99.9%) inhibit MRSA. Studies have shown that CoNS with 0.3% show the lowest resistance to linezolid and daptomycin, while analyzes introduced tigecycline with 1.6% resistance as the least effective antibiotic for these bacteria. Finally, MRSA and CoNS had a greater resistance to Q/D with 0.7 and 0.6%, respectively and due to its significant side effects and drug-drug interactions; it appears that its use is subject to limitations.

Conclusion

The present study shows that resistance to new agents is low in staphylococci and these antibiotics can still be used for treatment of staphylococcal infections in the world.

An intubated 7-month-old infant with a retropharyngeal abscess and multidrug-resistant Streptococcus mitis

The profile of antimicrobial resistance (ie, antibiogram) may be disparate between children and adults. An infant developed severe deep neck infection with a multidrug-resistant microbe. The microbe was more drug-resistant in children than in adults, in our hospital. Treatment of a child should be guided by the antibiogram obtained from children.

Optimizing gentamicin conventional and extended interval dosing in neonates using Monte Carlo simulation - a retrospective study

BACKGROUND

Although aminoglycosides are routinely used in neonates, controversy exists regarding empiric dosing regimens. The objectives were to determine gentamicin pharmacokinetics in neonates, and develop initial mg/kg dosing recommendations that optimized target peak and trough concentration attainment for conventional and extended-interval dosing (EID) regimens.

METHODS

Patient demographics and steady-state gentamicin concentration data were retrospectively collected for 60 neonates with no renal impairment admitted to a level III neonatal intensive care unit. Mean pharmacokinetics were calculated and multiple linear regression was performed to determine significant covariates of clearance (L/h) and volume of distribution (L). Classification and regression tree (CART) analysis identified breakpoints for significant covariates. Monte Carlo Simulation (MCS) was used to determine optimal dosing recommendations for each CART-identified sub-group.

RESULTS

Gentamicin clearance and volume of distribution were significantly associated with weight at gentamicin initiation. CART-identified breakpoints for weight at gentamicin initiation were: ≤ 850 g, 851-1200 g, and > 1200 g. MCS identified that a conventional dose of gentamicin 3.5 mg/kg given every 48 h or an EID of 8-9 mg/kg administered every 72 h in neonates weighing ≤ 850 g, and every 24 and 48 h, respectively, in neonates weighing 851-1200 g, provided the best probability of attaining conventional (peak: 5-10 mg/L and trough: ≤ 2 mg/L) and EID targets (peak:12-20 mg/L, trough:≤ 0.5 mg/L). Insufficient sample size in the > 1200 g neonatal group precluded further investigation of this weight category.

CONCLUSIONS

This study provides initial gentamicin dosing recommendations that optimize target attainment for conventional and EID regimens in neonates weighing ≤ 1200 g. Prospective validation and empiric dose optimization for neonates > 1200 g is needed.

The rise in vancomycin-resistant Enterococcus faecium in Germany: data from the German Antimicrobial Resistance Surveillance (ARS)

Background

Due to limited therapeutic options, vancomycin-resistant Enterococcus faecium (VREF) is of great clinical significance. Recently, rising proportions of vancomycin resistance in enterococcal infections have been reported worldwide. This study aims to describe current epidemiological trends of VREF in German hospitals and to identify factors that are associated with an increased likelihood of vancomycin resistance in clinical E. faecium isolates.

Methods

2012 to 2017 data from routine vancomycin susceptibility testing of 35,906 clinical E. faecium isolates from 148 hospitals were analysed using data from the German Antimicrobial Resistance Surveillance System. Descriptive statistical analyses and uni- and multivariable regression analyses were performed to investigate the impact of variables, such as year of sampling, age and region, on vancomycin resistance in clinical E. faecium isolates.

Results

From 2014 onwards the proportions of clinical E. faecium isolates exhibiting resistance to vancomycin increased from 11.2% (95% confidence interval [CI] 9.4-13.3%) to 26.1% (95% CI 23.1-29.4%) in 2017. The rise of VREF proportions is primarily observed in the southern regions of Germany, whereas northern regions do not show a major increase. In the Southwest and Southeast, VREF proportions increased from 10.8% (95% CI 6.9-16.5%) and 3.8% (95% CI 3.0-11.5%) in 2014 to 36.7% (95% CI 32.9-40.8%) and 36.8% (95% CI 29.2-44.7%) in 2017, respectively. VREF proportions were considerably higher in isolates from patients aged 40-59 years compared to younger patients. Further regression analyses show that in relation to secondary care hospitals, E. faecium samples collected in specialist care hospitals and prevention and rehabilitation care centres are more likely to be vancomycin-resistant (odds ratios: 2.4 [95% CI 1.2-4.6] and 2.4 [95% CI 1.9-3.0], respectively). No differences in VREF proportions were found between female and male patients as well as between different clinical specimens.

Conclusion

The proportion of VREF is increasing in German hospitals, particularly in southern regions in Germany. Increased efforts in infection control and antibiotic stewardship activities accounting for local resistance patterns are necessary to combat the spread of VREF in Germany.

Activity of ceftolozane-tazobactam and comparators against Pseudomonas aeruginosa from patients in different risk strata - SMART United States 2016-2017

OBJECTIVES

Infections caused by Pseudomonas aeruginosa are often difficult to treat. Knowledge of the risk of infection with resistant P. aeruginosa would allow more discriminatory prescribing of broad-spectrum antimicrobials. Using clinical isolates collected as part of the Study for Monitoring Antimicrobial Resistance Trends (SMART), we examined the activity of commonly used β-lactams, levofloxacin, and ceftolozane-tazobactam (C/T), an antipseudomonal cephalosporin/β-lactamase inhibitor approved in the United States and over 60 countries worldwide, against P. aeruginosa isolates from patients in different risk strata.

METHODS

In 2016-2017, 25 hospitals in the US each collected up to 250 consecutive gram-negative bacilli per year from respiratory tract (RTI), intraabdominal (IAI), and urinary tract (UTI) infections. MICs of 9,964 isolates (including 1,887 P. aeruginosa) were determined using CLSI broth microdilution and interpreted with CLSI breakpoints.

RESULTS

Susceptibility of all P. aeruginosa isolates combined was 94.7% to C/T and 76.8%, 77.0%, 70.2%, and 69.0% to ceftazidime, meropenem, piperacillin-tazobactam, and levofloxacin, respectively. Susceptibility to the β-lactam comparators was 8-11 percentage points lower among ICU than non-ICU isolates, 7-11 points lower in isolates collected ≥48h than <48h post-admission, 1-5 points lower in patients <65 years of age than older patients, and 3-12 points lower in RTI than IAI and UTI isolates. C/T maintained activity against >90% of P. aeruginosa isolates in all risk strata and against 75-88% of isolates nonsusceptible to ceftazidime, meropenem, or piperacillin-tazobactam.

CONCLUSIONS

C/T represents a promising new treatment option even in strata in which the risk of infection with β-lactam-nonsusceptible P. aeruginosa appeared higher.

Pharmacotherapy options and drug development in managing periprosthetic joint infections in the elderly

INTRODUCTION

Prosthetic joint infections are an increasingly important problem among patients undergoing arthroplasty procedures, and are associated with significant morbidity, reduced quality of life, substantial healthcare costs, and even mortality. Arthroplasties are performed with increasing frequency in elderly patients, who present specific problems.

AREAS COVERED

Surgical therapy is clearly influenced by the clinical status of the patient, which in some case can contraindicate surgery. Antibiotic selection is also affected by comorbidities and underlying diseases, which in some cases reduce therapeutic options. The authors review this together with the changes in pharmacokinetics and pharmacodynamics in the elderly population and the prospects for future research on prevention and treatment.

EXPERT OPINION

The management of PJI in the elderly makes multidisciplinary teams even more mandatory than in other patients, because the complexity of these patients. A frequent scenario is that in which surgery is contraindicated with long-term suppressive treatment as the only available option. Treating physicians must consider the presence of multiple comorbidities, interactions with other treatments and secondary effects when choosing antibiotic treatment. An in-depth knowledge of the alterations in pharmacokinetics and pharmacodynamics in elderly patients is key for a proper treatment selection.

Potential for More Rational Use of Antibiotics in Hospitalized Children in a Country With Low Resistance: Data From eight Point Prevalence Surveys

BACKGROUND

Antimicrobial resistance is low in Norway, but to prevent an increase, the Norwegian Government has launched a National Strategy including a 30% reduction of broad-spectrum antibiotics (BSA) in hospitals within 2020. BSA are defined as second- and third-generation cephalosporins, carbapenems, piperacillin/tazobactam and quinolones. There are no recent studies of antibiotic use in Norwegian hospitalized children. The aim of this study was to describe the use of antibiotics with emphasis on BSA in Norwegian hospitalized children and neonates to detect possibilities for optimization.

METHODS

Data were extracted from 8 national point prevalence surveys of systemic antibiotic prescriptions in Norwegian hospitals between 2015 and 2017. The choices of antibiotics were compared with the empirical recommendations given in available Norwegian guidelines. In total, 1323 prescriptions were issued for 937 patients.

RESULTS

Twenty-four percent of pediatric inpatients were given antibiotics. Adherence to guidelines was 48%, and 30% (95% confidence interval: 27%-33%) of all patients on antibiotics received BSA. We identified only small variations in use of BSA between hospitals. One-third of the patients on antibiotic therapy received prophylaxis whereof 13% were given BSA. In 30% of prescriptions with BSA, no microbiologic sample was obtained before treatment.

CONCLUSIONS

This study reveals an excess of prescriptions with BSA in relation to the low resistance rate in Norway. Our findings reveal areas for improvement that can be useful in the forthcoming antibiotic stewardship programs in Norwegian pediatric departments.

Pediatric bloodstream infections in metropolitan Australia

BACKGROUND

Bloodstream infections (BSIs) cause significant morbidity and mortality of children worldwide. The aim of this study was to investigate BSI in children and determine the identity of causative organism and their susceptibility patterns in a metropolitan public hospital in Australia.

METHODS

We retrospectively reviewed children aged 0-16 years admitted to a public hospital from January 1, 2010 to August 31, 2014 inclusive, and whose blood cultures revealed bacteraemia. Data were collected regarding patient demographics, species of bacteria isolated, antimicrobial susceptibility of these isolates, and clinical outcomes.

RESULTS

Out of 96 patients with BSI, 55 (57.3%) were males. The median age was 3.35 years (IQR 0.44-7.46), and there were 2 mortalities. Common sites of infection were the respiratory tract (16.6%, n = 16), bone and joints (15.6%, n = 15) and the urinary tract (11.5%, n = 11). The most frequent isolates were Staphylococcus aureus (27.0%), Escherichia coli (14.0%) and Streptococcus pneumoniae (12.0%). Whilst most bacterial isolates displayed susceptibility (> 90%) to common antimicrobial agents, only 57.1% (8/14) of Escherichia coli isolates were susceptible to ampicillin and 58.3% (7/12) were susceptible to co-trimoxazole.

CONCLUSIONS

Gram-positive bacteria accounted for the majority of pediatric BSIs, of which invasive pneumococcal disease remains a noteworthy cause. The majority of isolates, except Escherichia coli, were susceptible to commonly used antimicrobials. This study confirms the knowledge of high rates of resistance of Escherichia coli to ampicillin. Therefore, empirical treatment should still include gentamicin. Monitoring of resistance patterns is warranted to ensure that antibiotic therapy remains appropriate.

Aminoglycoside-inducible expression of the mexAB-oprM multidrug efflux operon in Pseudomonas aeruginosa: Involvement of the envelope stress-responsive AmgRS two-component system

Exposure of P. aeruginosa to the aminoglycoside (AG) paromomycin (PAR) induced expression of the PA3720-armR locus and the mexAB-oprM multidrug efflux operon that AmgR controls, although PAR induction of mexAB-oprM was independent of armR. Multiple AGs promoted mexAB-oprM expression and this was lost in the absence of the amgRS locus encoding an aminoglycoside-activated envelope stress-responsive 2-component system (TCS). Purified AmgR bound to the mexAB-oprM promoter region consistent with this response regulator directly regulating expression of the efflux operon. The thiol-active reagent, diamide, which, like AGs, promotes protein aggregation and cytoplasmic membrane damage also promoted AmgRS-dependent mexAB-oprM expression, a clear indication that the MexAB-OprM efflux system is recruited in response to membrane perturbation and/or circumstances that lead to this. Despite the AG and diamide induction of mexAB-oprM, however, MexAB-OprM does not appear to contribute to resistance to these agents.

Inappropriate Use of Antimicrobials for Lower Respiratory Tract Infections in Elderly Patients: Patient- and Community-Related Implications and Possible Interventions

The elderly are more susceptible to infections, which is reflected in the incidence and mortality of lower respiratory tract infections (LRTIs) increasing with age. Several aspects of antimicrobial use for LRTIs in elderly patients should be considered to determine appropriateness. We discuss possible differences in microbial etiology between elderly and younger adults, definitions of inappropriate antimicrobial use for LRTIs currently found in the literature, along with their results, and the possible negative impact of antimicrobial therapy at both an individual and community level. Finally, we propose that both antimicrobial stewardship interventions and novel rapid diagnostic techniques may optimize antimicrobial use in elderly patients with LRTIs.

Early Clinical Assessment of the Antimicrobial Activity of Finafloxacin Compared to Ciprofloxacin in Subsets of Microbiologically Characterized Isolates

Two phase II studies were performed with patients with uncomplicated urinary tract infections (uUTIs) and complicated urinary tract infections (cUTIs) or acute pyelonephritis (PN) to compare finafloxacin (300 mg twice a day [b.i.d.] orally for uUTI and 800 mg once a day [q.d.] intravenously [i.v.] for cUTI/PN) and ciprofloxacin (250 mg b.i.d. orally for uUTI and 400 mg b.i.d. i.v. for cUTI/PN). The early response to the study medications was evaluated in the microbiological intent-to-treat population (mITT) at day 3. A total of 21% of the isolates were ciprofloxacin resistant, 13.7% were primed pathogens carrying a mutation(s) potentially fostering fluoroquinolone resistance development, and 7.1% produced extended-spectrum β-lactamases (ESBLs). Finafloxacin demonstrated very good early clinical activity, with microbiological eradication rates of 88.6% (n = 132), compared to 78.7% (n = 61) for ciprofloxacin, and 69.6% (n = 23), compared to 35.7% (n = 14) for ciprofloxacin, in patients with ciprofloxacin-resistant uropathogens; 94.1% (n = 17), compared to 80.0% (n = 10) for ciprofloxacin, in patients infected with uropathogens primed for fluoroquinolone resistance uropathogens; and 91.7% (n = 11), compared to 0% for ciprofloxacin, in patients infected with ESBL producers. Finafloxacin demonstrated early and rapid activity against uropathogens, including fluoroquinolone-resistant and/or multiresistant pathogens or ESBL producers, while ciprofloxacin was less active against this subset of resistant pathogens. Susceptibilities of pathogens were quantitated by broth microdilution. Isolates were subgrouped according to their susceptibility patterns, in particular first-step quinolone resistance, quinolone resistance, and ESBL production. Eradication was defined as the elimination or reduction of study entry pathogens to <10³ CFU/ml in urine culture. (The studies described in this paper have been registered at ClinicalTrials.gov under identifiers NCT00722735 and NCT01928433.).

Knowledge and attitudes towards the use of antibiotics in the paediatric age group: a multicenter survey in Italy

Background

: The misuse of antibiotics is one of the leading causes of antibiotic resistance. Paediatric patients are highly involved in this issue, as they are those who receive the largest amount of prescriptions of these drugs. Therefore, this study aimed to investigate the general knowledge regarding the use of antibiotics, as well as the attitudes related to the administration of these drugs to children, amongst parents of children in the paediatric age-group. : In 2014, a multicentre cross-sectional study was conducted amongst parents of children aged 0-14. A questionnaire made up of 33 items was administered in waiting rooms of outpatient departments. Multivariable logistic regression models were performed, in order to assess the potential predictors of a better knowledge about antibiotics. : A total of 1247 parents took part to the survey. Around 33% of the samples declared that antibiotics are useful for viral infections, 20.6% that antibiotics are useful for every kind of pain and inflammation, while 14% of the parents stated that they stop giving antibiotics to their children when they start feeling better. Multivariable models showed that males, unemployed and those with lower levels of education are less prone to answer correctly to the questions about antibiotics. : The present study demonstrates that parents have a lack of knowledge regarding the use of antibiotics, which results in bad habits and inappropriate attitudes when it comes to giving antibiotics to their children. Attention should be particularly focused on disadvantaged parents.

Impact of long-term care facility residence on the antibiotic resistance of urinary tract Escherichia coli and Klebsiella

Background

Long-term care facilities (LTCFs) are thought to be important reservoirs of antimicrobial-resistant (AMR) bacteria; however, there is no routine surveillance of resistance in LTCF residents, or large population-based studies comparing AMR in LTCFs with the community, so the relative burden of AMR in LTCFs remains unknown.

Objectives

To compare the frequency of antibiotic resistance of urinary tract bacteria from residents of LTCFs for the elderly and adults aged 70 years or older living in the community.

Methods

Positive urine specimens reported to any diagnostic microbiology laboratory in the West Midlands region (England) from 1 April 2010 to 31 March 2014 collected from individuals aged 70 years or older were analysed. The resistance of Escherichia coli and Klebsiella to trimethoprim, nitrofurantoin, third-generation cephalosporins and ciprofloxacin and the rate of laboratory-confirmed E. coli and Klebsiella urinary tract infection (UTI) were assessed in LTCF residents and in the community.

Results

LTCF residents had a laboratory-confirmed E. coli and Klebsiella UTI rate of 21 per 100 person years compared with 8 per 100 person years in the elderly living in the community [rate ratio (RR)=2.66, 95% CI = 2.58-2.73] and a higher rate of developing E. coli and Klebsiella UTIs caused by bacteria resistant to trimethoprim (RR = 4.41, 95% CI = 4.25-4.57), nitrofurantoin (RR = 4.38, 95% CI = 3.98-4.83), ciprofloxacin (RR = 5.18, 95% CI = 4.82-5.57) and third-generation cephalosporins (RR = 4.49, 95% CI = 4.08-4.94).

Conclusions

Residents of LTCFs for the elderly had more than double the rate of E. coli and Klebsiella UTI and more than four times the rate of E. coli and Klebsiella UTI caused by antibiotic-resistant bacteria compared with those living in the community.

Antimicrobial resistance in bacterial pathogens among hospitalized children with community acquired lower respiratory tract infections in Dongguan, China (2011-2016)

BACKGROUND

Bacterial pathogens are a major cause of childhood community acquired lower respiratory tract infections (CA-LRTIs), and few data described the impact of antimicrobial resistance on children with CA-LRTIs. This study aims to investigate the antimicrobial resistance in common bacterial agents among hospitalized children with CA-LRTIs between 2011 and 2016 in Dongguan, China.

METHODS

Sputum samples were collected from hospitalized children (0-5 years old) with CA-LRTIs in Dongguan Children's Hospital. Bacterial pathogens were detected using traditional culture methods, and disc diffusion tests were used to determine antibiotic resistance.

RESULTS

Among the 2360 samples analyzed, 342 (14.5%) were positive for bacterial infection. The most prevalent pathogen was MSSA (2.3%), followed by MRSA (1.5%), E. coli (1.7%), E. coli ESBLs (1.2%), K. pneumonia ESBLs (1.5%), K. pneumonia (1.4%) and S. pneumonia (1.3%). Of the hospitalized patients with bacteria causing of CA-LRTIs, 90.1% were less than 1-year-old. MSSA and MRSA were more commonly isolated in infants less than 3 months. E. coli, K. pneumonia and K. pneumonia ESBLs were more common bacteria causing CA-LRTIs in infants less than 1 month. Resistance levels to penicillins, fluoroquinolones, macrolides, cephalosporins, carbapenems and vancomycin varied in different bacteria.

CONCLUSIONS

S. aureus, E coli and K. pneumonia were the common bacterial isolates recovered from chidren with CA-LTRIs during 2011-2015. Age group of under 1 year old was at a high risk of bacterial infections. Many isolates showed antibiotic resistance level was associated with antibiotic usage in clinic. Increasing surveillance of antibiotic resistance is urgently needed and develops better strategies to cure the antibiotic abuse in China.

The Use of Systemic and Topical Fluoroquinolones

Appropriate prescribing practices for fluoroquinolones, as well as all antimicrobial agents, are essential as evolving resistance patterns are considered, additional treatment indications are identified, and the toxicity profile of fluoroquinolones in children has become better defined. Earlier recommendations for systemic therapy remain; expanded uses of fluoroquinolones for the treatment of certain infections are outlined in this report. Prescribing clinicians should be aware of specific adverse reactions associated with fluoroquinolones, and their use in children should continue to be limited to the treatment of infections for which no safe and effective alternative exists or in situations in which oral fluoroquinolone treatment represents a reasonable alternative to parenteral antimicrobial therapy.

Five-Year Antimicrobial Resistance Patterns of Urinary Escherichia coli at an Australian Tertiary Hospital: Time Series Analyses of Prevalence Data

This study describes the antimicrobial resistance temporal trends and seasonal variation of Escherichia coli (E. coli) urinary tract infections (UTIs) over five years, from 2009 to 2013, and compares prevalence of resistance in hospital- and community-acquired E. coli UTI. A cross sectional study of E. coli UTIs from patients attending a tertiary referral hospital in Canberra, Australia was undertaken. Time series analysis was performed to illustrate resistance trends. Only the first positive E. coli UTI per patient per year was included in the analysis. A total of 15,022 positive cultures from 8724 patients were identified. Results are based on 5333 first E. coli UTIs, from 4732 patients, of which 84.2% were community-acquired. Five-year hospital and community resistance rates were highest for ampicillin (41.9%) and trimethoprim (20.7%). Resistance was lowest for meropenem (0.0%), nitrofurantoin (2.7%), piperacillin-tazobactam (2.9%) and ciprofloxacin (6.5%). Resistance to amoxycillin-clavulanate, cefazolin, gentamicin and piperacillin-tazobactam were significantly higher in hospital- compared to community-acquired UTIs (9.3% versus 6.2%; 15.4% versus 9.7%; 5.2% versus 3.7% and 5.2% versus 2.5%, respectively). Trend analysis showed significant increases in resistance over five years for amoxycillin-clavulanate, trimethoprim, ciprofloxacin, nitrofurantoin, trimethoprim-sulphamethoxazole, cefazolin, ceftriaxone and gentamicin (P<0.05, for all) with seasonal pattern observed for trimethoprim resistance (augmented Dickey-Fuller statistic = 4.136; P = 0.006). An association between ciprofloxacin resistance, cefazolin resistance and ceftriaxone resistance with older age was noted. Given the relatively high resistance rates for ampicillin and trimethoprim, these antimicrobials should be reconsidered for empirical treatment of UTIs in this patient population. Our findings have important implications for UTI treatment based on setting of acquisition.

Role of age and sex in determining antibiotic resistance in febrile urinary tract infections

OBJECTIVES

To identify the age- and sex-specific antimicrobial susceptibility patterns of Gram-negative bacteria (GNB) in outpatient febrile urinary tract infections (UTIs) in Korea.

METHODS

A total 2262 consecutive samples collected from patients aged 1-101 years with febrile UTIs, during the period January 2012 to December 2014, were analyzed in this multicentre, retrospective cohort study.

RESULTS

The sensitivities to cefotaxime and cefoxitin were over 85% for females but under 75% for males. Sex played an important role in the susceptibility of GNB to cefotaxime (p<0.001) and cefoxitin (p<0.001). The sensitivity to ciprofloxacin (age >20 years) was under 75% in both sexes, and was not influenced by sex (p=0.204). Age distributions of the incidences of resistance to cefotaxime, cefoxitin, and ciprofloxacin (age >20 years) were similar to the age distribution of the incidence of GNB, which indicates that the resistance patterns to these drugs were not affected by age (Kolmogorov-Smirnov test, female/male: p=0.927/p=0.509, p=0.193/p=0.911, and p=0.077/p=0.999, respectively).

CONCLUSIONS

Age is not a considerable factor in determining the antibiotic resistance in febrile UTIs. Ciprofloxacin should be withheld from both sexes until culture results indicate its use. Second- or third-generation cephalosporins such as cefoxitin and cefotaxime can be used empirically only in females.

Staphylococcal orthopaedic device-related infections in older patients

INTRODUCTION

Staphylococci are the most common pathogens causing orthopaedic device-related infections (ODRI). The treatment of these infections often involves multiple surgical procedures combined with systemic antibiotic therapy to treat the infection and restore functionality. Older patients frequently present with a compromised health-status and/or low bone quality, and despite growing importance their outcomes are not well described to date. The primary aim of the current study is to describe outcomes in older patients with ODRIs and to determine if they demonstrate lower cure rates and greater risk for complications in contrast to younger patients.

PATIENTS AND METHODS

Patients treated with an ODRI of the lower extremity at our institution were included in this study. Demographic data, comorbidities and infecting organisms were recorded. Older adult patients were defined as those aged 60 and older. At two-year follow-up post-discharge, we recorded the clinical course, the Lower-Extremity-Functional-Score, the patient reported general health status (SF-12-questionnaire) and the status of infection. The antibiotic resistance pattern of the disease causing pathogens was analysed and compared between the two age groups.

RESULTS

In total, 163 patients (age: 19-94 years) with a staphylococcal ODRI were included. Sixty-four of these infections occurred in older patients, which showed a significantly higher mortality rate (9%). Within follow-up period recurrence of infection occurred significantly more frequently in younger patients (41%) than in older patients (17%). At two-years follow-up cure, which was defined as eradication of infection and terminated therapy, was achieved in 78% of younger and 75% of older patients. However, an ODRI resulted in older patients in a significantly worse functional outcome and impaired physical quality of live, as well as more frequently in an on-going infection, such as a persisting fistula (14% versus 3% in younger patients). Disease causing staphylococci, isolated from older patients showed more frequently a methicillin or multi-drug resistance than those associated with infections in younger patients.

CONCLUSIONS

ODRIs in older patients demonstrated higher morality rates rate, poor functional outcome and higher rates of persistent infections. A compromised health status and a poor bone quality may play a crucial role in this specific patient cohort.

Antimicrobial resistance of Staphylococcus aureus isolated from skin infections and its implications in various clinical conditions in Korea

BACKGROUND

Periodic investigations into patterns of antimicrobial resistance can help to optimize the efficacy of treatment and limit the development of resistance.

OBJECTIVES

The aim of this study was to update information on patterns of antimicrobial resistance in Staphylococcus aureus isolated from skin infections in South Korea.

METHODS

We retrospectively analyzed clinical information and in vitro antimicrobial resistance data for 965 clinical S. aureus isolates obtained from skin infections during 2010-2013 in a university hospital in South Korea.

RESULTS

The rate of resistance to oxacillin (methicillin-resistant S. aureus [MRSA]) was 47.4%. Similar rates of resistance to erythromycin (45.6%), fusidic acid (44.0%), and clindamycin (42.3%) were noted. The rate of resistance to mupirocin was 8.4%. Overall, 4.9% of isolates were resistant to both fusidic acid and mupirocin. None of the isolates showed resistance to habekacin, synercid, teicoplanin, or vancomycin. Generally, antimicrobial resistance rates did not increase from 2010 to 2013 except with reference to a few agents such as mupirocin and rifampin. Isolates from surgical patients, inpatients, non-dermatology outpatients, and adult patients showed relatively high rates of resistance to multiple antimicrobials. Resistance to mupirocin was not only lower than that to fusidic acid but was consistent across clinical contexts.

CONCLUSIONS

The prevalence of MRSA in skin infections in South Korea did not increase during 2010-2013. Isolates from dermatology outpatients showed relatively lower rates of resistance to multiple antimicrobials than isolates from non-dermatology outpatients. Among topical antimicrobials, resistance to mupirocin was relatively low regardless of clinical condition.

Serotypes, antimicrobial susceptibility, and molecular epidemiology of invasive and non-invasive Streptococcus pneumoniae isolates in paediatric patients after the introduction of 13-valent conjugate vaccine in a nationwide surveillance study conducted in Japan in 2012-2014

Pneumococcal infection in children is a major public health problem worldwide, including in Japan. The pneumococcal conjugate vaccine 7 (PCV7) was licensed for use in Japan in 2010 followed by PCV13 in 2013. This report includes the results of a nationwide surveillance of invasive pneumococcal disease (IPD) and non-IPD in paediatric patients from January 2012 to December 2014. We collected 343 isolates from 337 IPD patients and 286 isolates from 278 non-IPD patients. Of the IPD isolates, the most identified serotypes included 19A, 24F, and 15A. The prevalence of non-PCV13 serotype isolates increased significantly from 2012 to 2014 (51.6-71.4%, p=0.004). Serotypes 19A, 15A and 35B were highly non-susceptible to penicillin, and the rates of non-susceptible isolates from IPD patients to penicillin and cefotaxime significantly declined during the study period (p=0.029 and p=0.013, respectively). The non-susceptible rate to meropenem increased, particularly for serotype 15A. The IPD isolates comprised clonal complex (CC) 3111 (93.8% was serotype 19A) followed by CC2572 (81.5% was serotype 24F) and CC63 (97.1% was serotype 15A). CC3111, CC63 and CC156 (33.3% was serotype 23A, 28.6% was serotype 6B, and 14.3% was serotype 19A) were highly non-susceptible to penicillin. Of the non-IPD isolates, the most identified serotypes included 19A, 15A, and 3. In conclusion, the introduction of PCV7 and PCV13 resulted in increasing non-PCV13 serotypes and clones, including antimicrobial resistant serotypes 15A and CC63 (Sweden(15A)-25 clone).

The Value of Macrolide-Based Regimens for Community-Acquired Pneumonia

Macrolide antimicrobials are commonly prescribed, specifically for the treatment of respiratory tract infections. Although still effective, the development of widespread macrolide resistance has limited their use. Aside from their antimicrobial effects, macrolides are also known to possess immune-modulatory properties which may confer a survival benefit in both acute and chronic inflammatory states. This review discusses the efficacy, potential mechanisms, and adverse effects of macrolide therapy specifically in community-acquired pneumonia in outpatients, hospitalized ward patients, and those requiring intensive care unit admission. Challenges for ongoing research in this field are discussed and treatment recommendations offered.

Impact of maternal intrapartum antibiotics, method of birth and breastfeeding on gut microbiota during the first year of life: a prospective cohort study

OBJECTIVE

Dysbiosis of the infant gut microbiota may have long-term health consequences. This study aimed to determine the impact of maternal intrapartum antibiotic prophylaxis (IAP) on infant gut microbiota, and to explore whether breastfeeding modifies these effects.

DESIGN

Prospective pregnancy cohort of Canadian infants born in 2010-2012: the Canadian Healthy Infant Longitudinal Development (CHILD) Study.

SETTING

General community.

SAMPLE

Representative sub-sample of 198 healthy term infants from the CHILD Study.

METHODS

Maternal IAP exposures and birth method were documented from hospital records and breastfeeding was reported by mothers. Infant gut microbiota was characterised by Illumina 16S rRNA sequencing of faecal samples at 3 and 12 months.

MAIN OUTCOME MEASURES

Infant gut microbiota profiles.

RESULTS

In this cohort, 21% of mothers received IAP for Group B Streptococcus prophylaxis or pre-labour rupture of membranes; another 23% received IAP for elective or emergency caesarean section (CS). Infant gut microbiota community structures at 3 months differed significantly with all IAP exposures, and differences persisted to 12 months for infants delivered by emergency CS. Taxon-specific composition also differed, with the genera Bacteroides and Parabacteroides under-represented, and Enterococcus and Clostridium over-represented at 3 months following maternal IAP. Microbiota differences were especially evident following IAP with emergency CS, with some changes (increased Clostridiales and decreased Bacteroidaceae) persisting to 12 months, particularly among non-breastfed infants.

CONCLUSIONS

Intrapartum antibiotics in caesarean and vaginal delivery are associated with infant gut microbiota dysbiosis, and breastfeeding modifies some of these effects. Further research is warranted to explore the health consequences of these associations.

TWEETABLE ABSTRACT

Maternal #antibiotics during childbirth alter the infant gut #microbiome.