Changing Susceptibility of Staphylococcus aureus in a US Pediatric Population

Potential therapeutic agents of Bombyx mori silk cocoon extracts from agricultural product for inhibition of skin pathogenic bacteria and free radicals

Background

Pathogenic bacteria are the cause of most skin diseases, but issues such as resistance and environmental degradation drive the need to research alternative treatments. It is reported that silk cocoon extract possesses antioxidant properties. During silk processing, the degumming of silk cocoons creates a byproduct that contains natural active substances. These substances were found to have inhibitory effects on bacterial growth, DNA synthesis, the pathogenesis of hemolysis, and biofilm formation. Thus, silk cocoon extracts can be used in therapeutic applications for the prevention and treatment of skin pathogenic bacterial infections.

Methods

The extract of silk cocoons with pupae (SCP) and silk cocoons without pupae (SCWP) were obtained by boiling with distilled water for 9 h and 12 h, and were compared to silkworm pupae (SP) extract that was boiled for 1 h. The active compounds in the extracts, including gallic acid and quercetin, were determined using high-performance liquid chromatography (HPLC). Furthermore, the total phenolic and flavonoid content in the extracts were investigated using the Folin-Ciocalteu method and the aluminum chloride colorimetric method, respectively. To assess antioxidant activity, the extracts were evaluated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. Additionally, the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of silk extracts and phytochemical compounds were determined against skin pathogenic bacteria. This study assessed the effects of the extracts and phytochemical compounds on growth inhibition, biofilm formation, hemolysis protection, and DNA synthesis of bacteria.

Results

The HPLC characterization of the silk extracts showed gallic acid levels to be the highest, especially in SCP (8.638-31.605 mg/g extract) and SP (64.530 mg/g extract); whereas quercetin compound was only detected in SCWP (0.021-0.031 mg/g extract). The total phenolics and flavonoids in silk extracts exhibited antioxidant and antimicrobial activity. Additionally, SCP at 9 h and 12 h revealed the highest anti-bacterial activity, with the lowest MIC and MBC of 50-100 mg/mL against skin pathogenic bacteria including Staphylococcus aureus, methicillin-resistant S. aureus (MRSA), Cutibacterium acnes and Pseudomonas aeruginosa. Hence, SCP extract and non-sericin compounds containing gallic acid and quercetin exhibited the strongest inhibition of both growth and DNA synthesis on skin pathogenic bacteria. The suppression of bacterial pathogenesis, including preformed and matured biofilms, and hemolysis activity, were also revealed in SCP extract and non-sericin compounds. The results show that the byproduct of silk processing can serve as an alternative source of natural phenolic and flavonoid antioxidants that can be used in therapeutic applications for the prevention and treatment of pathogenic bacterial skin infections.

Recent development and fighting strategies for lincosamide antibiotic resistance

SUMMARYLincosamides constitute an important class of antibiotics used against a wide range of pathogens, including methicillin-resistant Staphylococcus aureus. However, due to the misuse of lincosamide and co-selection pressure, the resistance to lincosamide has become a serious concern. It is urgently needed to carefully understand the phenomenon and mechanism of lincosamide resistance to effectively prevent and control lincosamide resistance. To date, six mobile lincosamide resistance classes, including lnu, cfr, erm, vga, lsa, and sal, have been identified. These lincosamide resistance genes are frequently found on mobile genetic elements (MGEs), such as plasmids, transposons, integrative and conjugative elements, genomic islands, and prophages. Additionally, MGEs harbor the genes that confer resistance not only to antimicrobial agents of other classes but also to metals and biocides. The ultimate purpose of discovering and summarizing bacterial resistance is to prevent, control, and combat resistance effectively. This review highlights four promising strategies, including chemical modification of antibiotics, the development of antimicrobial peptides, the initiation of bacterial self-destruct program, and antimicrobial stewardship, to fight against resistance and safeguard global health.

Epidemiological and microbiological characteristics of S. aureus pediatric infections in Colombia 2018-2021, a national multicenter study (Staphylored Colombia)

Background

Staphylococcus aureus infections are a significant cause of morbidity and mortality in pediatric populations worldwide. The Staphylo Research Network conducted an extensive study on pediatric patients across Colombia from 2018 to 2021. The aim of this study was to describe the epidemiological and microbiological characteristics of S. aureus in this patient group.

Methods

We analyzed S. aureus isolates from WHONET-reporting centers. An "event" was a positive culture isolation in a previously negative individual after 2 weeks. We studied center characteristics, age distribution, infection type, and antibiotic susceptibilities, comparing methicillin sensitive (MSSA) and resistant S. aureus (MRSA) isolates.

Results

Isolates from 20 centers across 7 Colombian cities were included. Most centers (80%) served both adults and children, with 55% offering oncology services and 85% having a PICU. We registered 8,157 S. aureus culture isolations from 5,384 events (3,345 MSSA and 1,961 MRSA) in 4,821 patients, with a median age of 5 years. Blood (26.2%) and skin/soft tissue (18.6%) were the most common infection sources. Most isolates per event remained susceptible to oxacillin (63.2%), clindamycin (94.3%), and TMP-SMX (98.3%). MRSA prevalence varied by city (<0.001), with slightly higher rates observed in exclusively pediatric hospitals. In contrast, the MRSA rate was somewhat lower in centers with Antimicrobial Stewardship Program (ASP). MRSA was predominantly isolated from osteoarticular infections and multiple foci, while MSSA was more frequently associated with recurrent infections compared to MRSA.

Conclusions

This is the largest study of pediatric S. aureus infections in Colombia. We found MSSA predominance, but resistance have important regional variations. S. aureus remains susceptible to other commonly used antibiotics such as TMP-SMX and clindamycin. Ongoing monitoring of S. aureus infections is vital for understanding their behavior in children. Prospective studies within the Staphylored LATAM are underway for a more comprehensive clinical and genetic characterization.

Antimicrobial Resistance Patterns of Outpatient Staphylococcus aureus Isolates

Importance

Oral non-β-lactam antibiotics are commonly used for empirical therapy of Staphylococcus aureus infections, especially in outpatient settings. However, little is known about potential geographic heterogeneity and temporal trends in the prevalence of S aureus resistance to non-β-lactams in the US.

Objective

To characterize the spatiotemporal trends of resistance to non-β-lactam antibiotics among community-onset S aureus infections, including regional variation in resistance rates and geographical heterogeneity in multidrug resistance.

Design, Setting, and Participants

This cross-sectional study used data from Veterans Health Administration clinics collected from adult outpatients with S aureus infection in the conterminous 48 states and Washington, DC, from January 1, 2010, to December 31, 2019. Data were analyzed from January to November 2023.

Exposures

Resistance to lincosamides (clindamycin), tetracyclines, sulfonamides (trimethoprim-sulfamethoxazole [TMP-SMX]), and macrolides.

Main Outcomes and Measures

Spatiotemporal variation of S aureus resistance to these 4 classes of non-β-lactam antibiotics, stratified by methicillin-resistant S aureus (MRSA) and methicillin-sensitive S aureus (MSSA), and subdivided by regions of the US (Northeast, Midwest, South, and West). Trend tests and bivariate mapping were used to determine significant changes in resistant proportions over time and identify counties where rates of resistance to multiple non-β-lactams were high.

Results

A total of 382 149 S aureus isolates from 268 214 unique outpatients (mean [SD] age, 63.4 [14.8] years; 252 910 males [94.29%]) were analyzed. There was a decrease in the proportion of MRSA nationwide, from 53.6% in 2010 to 38.8% in 2019. Among MRSA isolates, we observed a significant increase in tetracycline resistance (from 3.6% in 2010 to 12.8% in 2019; P for trend < .001) and TMP-SMX resistance (from 2.6% in 2010 to 9.2% in 2019; P for trend < .001), modest and not significant increases in clindamycin resistance (from 24.2% in 2010 to 30.6% in 2019; P for trend = .34), and a significant decrease in macrolide resistance (from 73.5% in 2010 to 60.2% in 2019; P for trend < .001). Among MSSA isolates, significant upward trends in clindamycin, tetracyclines, and TMP-SMX resistance were observed. For example, tetracycline resistance increased from 3.7% in 2010 to 9.1% in 2019 (P for trend < .001). Regional stratification over time showed that the Northeast had slightly higher rates of clindamycin resistance but lower rates of tetracycline resistance, while the South had notably higher rates of resistance to tetracyclines and TMP-SMX, particularly among MRSA isolates. Bivariate mapping at the county scale did not indicate clear regional patterns of shared high levels of resistance to the 4 classes of antimicrobials studied.

Conclusions and Relevance

In this study of outpatient S aureus isolates, MRSA became less common over the 10-year period, and MRSA isolates were increasingly resistant to tetracyclines and TMP-SMX. Geographic analysis indicated no spatial overlap in counties with high rates of resistance to both tetracyclines and TMP-SMX. Examining the regional spatial variation of antibiotic resistance can inform empirical therapy recommendations and help to understand the evolution of S aureus antibiotic resistance mechanisms.

Clonal Diversity, Antibiotic Resistance, and Virulence Factor Prevalence of Community Associated Staphylococcus aureus in Southeastern Virginia

Staphylococcus aureus is a significant human pathogen with a formidable propensity for antibiotic resistance. Worldwide, it is the leading cause of skin and soft tissue infections (SSTI), septic arthritis, osteomyelitis, and infective endocarditis originating from both community- and healthcare-associated settings. Although often grouped by methicillin resistance, both methicillin-resistant (MRSA) and methicillin-sensitive (MSSA) strains are known to cause significant pathologies and injuries. Virulence factors and growing resistance to antibiotics play major roles in the pathogenicity of community-associated strains. In our study, we examined the genetic variability and acquired antibiograms of 122 S. aureus clinical isolates from SSTI, blood, and urinary tract infections originating from pediatric patients within the southeast region of Virginia, USA. We identified a suite of clinically relevant virulence factors and evaluated their prevalence within these isolates. Five genes (clfA, spA, sbi, scpA, and vwb) with immune-evasive functions were identified in all isolates. MRSA isolates had a greater propensity to be resistant to more antibiotics as well as significantly more likely to carry several virulence factors compared to MSSA strains. Further, the carriage of various genes was found to vary significantly based on the infection type (SSTI, blood, urine).

Antibiotic resistance in bloodstream isolates from high-complexity paediatric units in Madrid, Spain: 2013-2021

BACKGROUND

Antimicrobial resistance (AMR) has become a significant challenge in high-complexity healthcare settings.

AIM

To evaluate the prevalence of AMR in bloodstream isolates from high-complexity paediatric units in Spain over a nine-year period.

METHODS

A retrospective observational multicentre study was conducted in three tertiary hospitals, analysing bloodstream isolates from patients aged <18 years admitted to the paediatric intensive care, neonatology, and oncology-haematology units between 2013 and 2021. Demographics, antimicrobial susceptibility, and resistance mechanisms were analysed in two periods (2013-2017 and 2017-2021).

FINDINGS

In all, 1255 isolates were included. AMR was more prevalent in older patients and those admitted to the oncology-haematology unit. Multidrug resistance was observed in 9.9% of Gram-negative bacteria (GNB); 20.0% of P. aeruginosa vs 8.6% of Entero-bacterales (P < 0.001), with an increase in Enterobacterales from 6.2% to 11.0% between the first and the second period (P = 0.021). Difficult-to-treat resistance was observed in 2.7% of GNB; 7.4% of P. aeruginosa vs 1.6% of Enterobacterales (P < 0.001), with an increasing trend in Enterobacterales from 0.8% to 2.5% (P = 0.076). Carbapenem resistance among Enterobacterales increased from 3.5% to 7.2% (P = 0.029), with 3.3% producing carbapenemases (67.9% VIM). Meticillin resistance was observed in 11.0% of S. aureus and vancomycin resistance in 1.4% of Enterococcus spp., with both rates remaining stable throughout the study period.

CONCLUSION

This study reveals a high prevalence of AMR in high-complexity paediatric units. Enterobacterales showed a concerning increasing trend in resistant strains, with higher rates among older patients and those admitted to oncology-haematology units.

Retrospective Study on Staphylococcus aureus Resistance Profile and Antibiotic Use in a Pediatric Population

The growing phenomenon of antibiotic resistance and the presence of limited data concerning the pediatric area prompted us to focus on Staphylococcus aureus infection in this study, its antibiotic resistance profile, and the therapeutic management of affected children. We conducted a retrospective study by collecting clinical data on infants and children with antibiogram-associated S. aureus infection. We enrolled 1210 patients with a mean age of 0.9 years. We analyzed the resistance patterns and found 61.5% resistance to oxacillin, 58.4% resistance to cephalosporins, 41.6% resistance to aminoglycosides, and 38.3% resistance to fluoroquinolones. Importantly, we found no resistance to glycopeptides, a key antibiotic for MRSA infections whose resistance is increasing worldwide. We also found that the main risk factors associated with antibiotic resistance are being aged between 0 and 28 days, the presence of devices, and comorbidities. Antibiotic resistance is a growing concern; knowing the resistance profiles makes it possible to better target the therapy; however, it is important to use antibiotics according to the principles of antibiotic stewardship to limit their spread.

Community-acquired and healthcare-associated Staphylococcus aureus infections in a pediatric hospital in southern Brazil over 8 years: how common is MRSA?

Backgrounds

Both healthcare-associated and community-acquired methicillin-resistant Staphylococcus aureus (MRSA) infections are relevant in children. The objective of our study was to evaluate their impact in a pediatric hospital in southern Brazil.

Methods

Data from patients under 18 years of age with S. aureus infections between January 2013 and December 2020 were retrospectively analyzed. Data were collected regarding infection site, infection type (community-acquired or healthcare-associated), susceptibility to oxacillin [methicillin-susceptible S. aureus (MSSA) or MRSA] and other antimicrobials. We analyzed the evolution of the susceptibility rates for the isolates over this period.

Results

A total of 563 patients were included, among whom the prevalences of community- and hospital-acquired MRSA infections were 46.1% and 8.1%, respectively. No significant change occurred in these prevalences over the study period. In community-acquired infections, MSSA was significantly more associated with osteoarticular infections and MRSA was more associated with respiratory and intra-abdominal infections. In healthcare-associated infections, there was an association between MSSA and primary bloodstream infections and between MRSA, skin/soft tissue infections, and respiratory infections. Community-acquired MRSA were highly susceptible to trimethoprim-sulfamethoxazole (96.1%), clindamycin (88.4%), and doxycycline (99.0%).

Conclusion

Our study draws attention to the high rates of MRSA in community-acquired staphylococcal infections in this population, indicating a need to review initial protocols for severe staphylococcal infections according to local epidemiology.

Twenty-Five Year Trend Change in the Etiology of Pediatric Invasive Bacterial Infections in Korea, 1996-2020

BACKGROUND

The coronavirus disease-2019 (COVID-19) pandemic has contributed to the change in the epidemiology of many infectious diseases. This study aimed to establish the pre-pandemic epidemiology of pediatric invasive bacterial infection (IBI).

METHODS

A retrospective multicenter-based surveillance for pediatric IBIs has been maintained from 1996 to 2020 in Korea. IBIs caused by eight bacteria (Streptococcus pneumoniae, Haemophilus influenzae, Neisseria meningitidis, Staphylococcus aureus, Streptococcus agalactiae, Streptococcus pyogenes, Listeria monocytogenes, and Salmonella species) in immunocompetent children > 3 months of age were collected at 29 centers. The annual trend in the proportion of IBIs by each pathogen was analyzed.

RESULTS

A total of 2,195 episodes were identified during the 25-year period between 1996 and 2020. S. pneumoniae (42.4%), S. aureus (22.1%), and Salmonella species (21.0%) were common in children 3 to 59 months of age. In children ≥ 5 years of age, S. aureus (58.1%), followed by Salmonella species (14.8%) and S. pneumoniae (12.2%) were common. Excluding the year 2020, there was a trend toward a decrease in the relative proportions of S. pneumoniae (r_s = -0.430, P = 0.036), H. influenzae (r_s = -0.922, P < 0.001), while trend toward an increase in the relative proportion of S. aureus (r_s = 0.850, P < 0.001), S. agalactiae (r_s = 0.615, P = 0.001), and S. pyogenes (r_s = 0.554, P = 0.005).

CONCLUSION

In the proportion of IBIs over a 24-year period between 1996 and 2019, we observed a decreasing trend for S. pneumoniae and H. influenzae and an increasing trend for S. aureus, S. agalactiae, and S. pyogenes in children > 3 months of age. These findings can be used as the baseline data to navigate the trend in the epidemiology of pediatric IBI in the post COVID-19 era.

Molecular Characteristics of Methicillin-Resistant and Susceptible Staphylococcus aureus from Pediatric Patients in Eastern China

Staphylococcus aureus is an opportunistic pathogen that causes invasive infections in humans. In recent years, increasing studies have focused on the prevalence of S. aureus infections in adults; however, the epidemiology and molecular characteristics of S. aureus from Chinese pediatric patients remain unknown. The present study examined the population structure, antimicrobial resistance, and virulent factors of methicillin-resistant and -susceptible S. aureus isolated from Chinese pediatric patients from one medical center in eastern China. A total of 81 cases were screened with positive S. aureus infections among 864 pediatric patients between 2016 and 2022 in eastern China. Molecular analysis showed that ST22 (28.4%) and ST59 (13.6%) were the most typical strains, and associations between different clonal complex (CC) types/serotype types (ST) and the age of pediatric patients were observed in this study. CC398 was the predominant type in neonates under 1 month of age, while CC22 was mainly found in term-infant (under 1 year of age) and toddlers (over 1 year of age). Additionally, 17 S. aureus isolates were resistant to at least three antimicrobials and majority of them belonged to CC59. The blaZ gene was found in 59 isolates and mecA gene was present in 26 strains identified as methicillin-resistant. Numerous virulent factors were detected in S. aureus isolated from present pediatric patients. Remarkably, lukF-PV and lukS-PV were dominantly carried by CC22, tsst-1 genes were detected in CC188, CC7, and CC15, while exfoliative toxin genes were found only in CC121. Only 41.98% of the S. aureus isolates possessed scn gene, indicating that the sources of infections in pediatric patients may include both human-to-human transmissions as well as environmental and nosocomial infections. Together, the present study provided a phylogenetic and genotypic comparison of S. aureus from Chinese pediatric patients in Suzhou city. Our results suggested that the colonization of multi-drug resistant isolates of S. aureus may raise concern among pediatric patients, at least from the present medical center in eastern China.

Acute bacterial skin and skin structure infections in pediatric patients: potential role of dalbavancin

INTRODUCTION

Acute bacterial skin and skin structure infections (ABSSSIs) are a subtype of skin and soft tissue infections (SSTI), usually sustained by Gram-positive bacteria, whose incidence is high among children. ABSSSIs are responsible for a considerable number of hospitalizations. Moreover, as multidrug resistant (MDR) pathogens become widespread, the pediatric category seems burdened with an increased risk of resistance and treatment failure.

AREAS COVERED

To obtain a view on the status of the field, we describe the clinical, epidemiological, and microbiological aspects of ABSSSI in children. Old and new treatment options were critically revised with a focus on the pharmacological characteristics of dalbavancin. Evidence on the use of dalbavancin in children was collected, analyzed, and summarized.

EXPERT OPINION

Many of the therapeutic options available at the moment are characterized by the need for hospitalization or repeated intravenous infusions, safety issues, possible drug-drug interactions, and reduced efficacy on MDRs. Dalbavancin, the first long-acting molecule with strong activity against methicillin-resistant and also many vancomycin-resistant pathogens represents a game changer for adult ABSSSI. In pediatric settings, the available literature is still limited, but a growing body of evidence supports dalbavancin use in children with ABSSSI, demonstrating this drug to be safe and highly efficacious.

Skin Antiseptics for Atopic Dermatitis: Dissecting Facts From Fiction

Staphylococcus aureus is a known trigger and cause of infectious complications in atopic dermatitis (AD). Various antiseptics have been used in an attempt to decrease the burden of S. aureus in AD. In this Commentary, we present the evidence for and against some of the commonly used antiseptics in clinical and research settings. These agents remain attractive as an adjunct therapy for AD owing to their relative low cost and potential benefits of reducing S. aureus. Although a number of studies have evaluated the use of dilute bleach, its mechanisms remain controversial. A higher concentration of bleach than the commonly used 0.005% is likely needed for its anti-S. aureus effect. Silver-coated textiles have demonstrated anti-S. aureus effects in various studies; however, their efficacy and side effects in AD remain to be confirmed. Other antiseptics including chlorhexidine, triclosan, and triclocarban are also discussed. Variables that may affect the outcomes of these studies include length of use, concurrent application of moisturizers, and anti-inflammatory medications.

Trends in pediatric community-onset Staphylococcus aureus antibiotic susceptibilities over a five-year period in a multihospital health system

The epidemiology of community-onset Staphylococcus aureus infections is evolving. We performed a multihospital, retrospective study of pediatric community-onset S. aureus susceptibilities between 2015 and 2020. Oxacillin and clindamycin susceptibility remained lower at 67% and 75%, respectively. Tetracycline and trimethoprim-sulfamethoxazole susceptibility remained high at >90%. Oxacillin susceptibility was highest in invasive infections.

Microbiology of fracture related infections

Fracture related infection remains a challenging complication that creates a heavy burden for orthopaedic trauma patients, their families, treating physicians and healthcare systems. Even current curative approaches (radical debridement, revision surgery and long-term antibiotics) often result in significant socioeconomic costs and the risk of life-long functional impairment to the patient. The prevalence of osteomyelitis due to trauma and surgical complications does not seem to be diminishing in our society and the emergence of antimicrobial resistance is a major health related concern with global relevance. Despite multi-drug resistant bacteria being on the rise universally, perioperative antibiotic prophylaxis in orthopaedic trauma care has only slightly changed in the last 25 years. Staphylococcus infections remain an increasing global concern, partially due to the resistance mechanisms developed by staphylococci to evade the host immune system and antibiotic treatment, and as such antibiotics are becoming increasingly ineffective. This paper will address fracture related infections in trauma patients, looking at the bacteriology of these infections, its clinical implications and evolving nature.

Changes in Etiology of Invasive Bacterial Infections in Infants Under 3 Months of Age in Korea, 2006-2020

OBJECTIVES

Invasive bacterial infection (IBI) causes a significant burden in infants. In this study, we analyzed changes in epidemiology of IBI among infants in Korea.

METHODS

A retrospective multicenter-based surveillance for IBIs in infants <3 months of age was performed during 2006-2020. Cases were classified as an early-onset disease (EOD) (0-6 days) or late-onset disease (LOD) (7-89 days). The temporal trend change in proportion of pathogens was analyzed.

RESULTS

Among 1545 cases, the median age was 28 days (IQR: 12, 53) and EOD accounted for 17.7%. Among pathogens, S. agalactiae (40.4%), E. coli (38.5%), and S. aureus (17.8%) were the most common and attributed for 96.7%. Among EOD (n = 274), S. agalactiae (45.6%), S. aureus (31.4%), E. coli (17.2%) and L. monocytogenes (2.9%) were most common. Among LOD (n = 1274), E. coli (43.1%), S. agalactiae (39.3%), S. aureus (14.9%) and S. pneumoniae (1.3%) were most common. In the trend analysis, the proportion of S. aureus (r s = -0.850, P < 0.01) decreased significantly, while that of S. agalactiae increased (r s = 0.781, P < 0.01).

CONCLUSION

During 2006-2020, among IBI in infants <3 months of age, S. agalactiae, E. coli, and S. aureus were most common and an increasing trend of S. agalactiae was observed.

Omphalitis Hospitalizations at a US Children's Hospital

OBJECTIVES

To describe demographics, presentation, resource use, and outcomes of patients diagnosed with omphalitis.

METHODS

This was a retrospective descriptive study of infants with omphalitis at a children's hospital system between January 2006 and December 2020. Presentation, resource use, and outcomes (omphalitis complications [eg, necrotizing fasciitis], 30-day related cause revisit, and death) were described.

RESULTS

Ninety-one patients had a primary or secondary International Classification of Diseases, Ninth or 10th Revision, code for omphalitis. Seventy-eight patients were included in analysis (47 with omphalitis as primary reason for admission). Patients with omphalitis as the primary reason for admission presented with rash (44 of 47, 93.6%), fussiness/irritability (19 of 47, 40.4%), and fever (6 of 47, 12.8%). C-reactive protein was minimally elevated, with a median of 0.4 mg/dL (interquartile range 0.29-0.85).Among all patients, blood cultures were positive in 3 (3 of 78, 3.8%) and most had positive wound cultures (70 of 78, 89.7%), with primarily gram-positive organisms. Median duration of intravenous antibiotics was 5 days (interquartile range 3-7). No patients had complications of omphalitis or death. Five patients (5 of 78, 6.4%) had a 30-day revisit for a related cause.

CONCLUSIONS

We found variation in presentation and management of patients with omphalitis at our tertiary children's hospital system. Wound cultures, but not blood tests, were helpful in guiding management in the majority of cases. There were no complications of omphalitis or deaths.

Staphylococcus aureus Colonization in Healthy Children during the First Year of the Severe Acute Respiratory Syndrome Coronavirus 2 Pandemic

The early severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic was temporally associated with a reduction in many childhood infections, although the impact on bacterial colonization is unknown. We longitudinally assessed Staphylococcusaureus colonization prior to and through the first year of the pandemic. We observed a decline in methicillin-resistant Staphylococcus aureus colonization associated with SARS-CoV-2 prevention mandates.

Role of Daptomycin in Cutaneous Wound Healing: A Narrative Review

Daptomycin is active against Gram-positive bacteria, including methicillin-resistant Staphylococcus aureus (MRSA) and the on-label indications for its use include complicated skin and skin structure infections (cSSSI). We performed a narrative review of the literature with the aim to evaluate the role of daptomycin in the skin wound healing process, proposing our point of view on the possible association with other molecules that could improve the skin healing process. Daptomycin may improve wound healing in MRSA-infected burns, surgical wounds, and diabetic feet, but further studies in humans with histological examination are needed. In the future, the combination of daptomycin with other molecules with synergistic action, such as vitamin E and derivates, IB-367, RNA III-inhibiting peptide (RIP), and palladium nanoflowers, may help to improve wound healing and overcome forms of antibiotic resistance.

Antimicrobial Resistance Patterns of Bacterial and Fungal Isolates in COVID-19

Background: The pattern of bacterial infection in coronavirus disease 2019 (COVID-19) patients differ worldwide. Objectives: This study aimed to determine the patterns of bacterial infections and the antibiotic resistance profile by VITEK 2 (bioMérieux, France) in the culture of blood samples from hospitalized patients with COVID-19. Methods: This retrospective descriptive cross-sectional was conducted on a total of 25 patients with critical COVID-19 admitted to Imam Reza Hospital in Mashhad, Iran, during the first three COVID-19 peaks (2019 - 2020). Results: Among Gram-positive bacteria, two strains isolated from Staphylococcus aureus were methicillin-resistant S. aureus at a concentration of > 2 μg/mL. Enterococcus was vancomycin-resistant Enterococcus at a concentration of higher than 4 μg/mL (the minimum inhibitory concentration [MIC] ≥ 32). Among Gram-negative bacteria, three strains of Acinetobacter baumannii complex were extensively drug-resistant. Conclusions: There is evidence of the remarkable increase of various antibiotics’ MIC during the COVID-19 pandemic, which highlights the impact of the use of steroids on the risk of developing antimicrobial resistance during the COVID-19 pandemic.

Skin and Soft Tissue Infection Treatment and Prevention Practices by Pediatric Emergency Medicine Providers

OBJECTIVE

The aim of the study was to evaluate skin and soft tissue infection (SSTI) treatment and prevention practices among pediatric emergency medicine (PEM) clinicians in the context of current clinical practice guidelines and contemporary evidence.

METHODS

This was a cross-sectional survey of PEM clinicians belonging to the American Academy of Pediatrics Section on Emergency Medicine Survey listserv. Four varying hypothetical clinical scenarios of children with SSTI were posed to respondents; subsequent items assessed SSTI treatment and prevention practices. Provider demographics were collected.

RESULTS

Of 160 survey respondents, more than half stated that they would prescribe oral antibiotics for each clinical scenario, particularly for more complex presentations (small uncomplicated abscess, 51.8%; large uncomplicated abscess, 71.5%; recurrent abscess, 83.5%; febrile abscess, 90.3%; P < 0.001). Most commonly selected antibiotics were clindamycin and trimethoprim-sulfamethoxazole. Across scenarios, more than 80% selected a duration of treatment 7 days or more. Of the 121 respondents who prescribe preventive measures, 85.1% recommend hygiene measures; 52.5% would prescribe decolonization with topical antibiotic ointment and 77.5% would recommend antiseptic body washes. Half of the respondents reported that their institution has standard guidance for SSTI management.

CONCLUSIONS

Although current evidence supports adjuvant antibiotics for all drained SSTI and decolonization for the index patient and household contacts, PEM clinicians do not consistently adhere to these recommendations. In light of these findings, development and implementation of institutional guidelines are necessary to aid PEM clinicians' point-of-care decision making and improving evidence-based practice.

A Multicenter Analysis of Changes in Pediatric Antibiotic Susceptibilities Among Staphylococcus aureus and Pseudomonas aeruginosa Isolates: 2014–2018

OBJECTIVE

To describe antibiotic susceptibilities for Staphylococcus aureus and Pseudomonas aeruginosa among pediatric institutions in 2018. To assess correlations between antibiotic utilization and susceptibilities.

METHODS

Institutional antibiograms from 2018 were compiled among 13 institutions via a survey. Resistant pathogens and antibiotic days of therapy/1000 patient days (PD) were collected from 6 institutions over 5 years. Correlations were assessed as pooled data among all institutions and relative changes within individual institutions.

RESULTS

All 8552 S aureus isolates in 2018 were vancomycin susceptible and 40.1% were methicillin resistant (MRSA). Among MRSA, 96.3% and 78.8% were susceptible to trimethoprim/sulfamethoxazole and clindamycin, respectively. Pooled yearly MRSA/1000 PD decreased from 2014–2018 and correlated with pooled yearly decreases in vancomycin utilization (R = 0.983, p = 0.003). Institutional relative decreases in vancomycin utilization from 2014–2018 did not correlate with institutional relative decreases in MRSA susceptibility (R = −0.659, p = 0.16). Susceptibility to meropenem was 90.9% among 2315 P aeruginosa isolates in 2018. Antipseudomonal beta-lactam susceptibility ranged from 89.4% to 92.3%. Pooled yearly meropenem-resistant P aeruginosa/1000 PD and meropenem utilization did not significantly decrease over time or correlate (both p &gt; 0.6). Institutional relative change in meropenem utilization from 2013–2017 correlated with the institutional relative change in P aeruginosa susceptibility to meropenem from 2014–2018 (Rs = −0.89, p = 0.019).

CONCLUSIONS

Among included institutions, the burden of MRSA decreased over time. Institutional MRSA prevalence did not consistently correlate with institutional vancomycin utilization. Institutional changes in meropenem utilization correlated with P aeruginosa susceptibility the following year. Pooled analyses did not illustrate this correlation, likely owing to variability in utilization between institutions.

High prevalence of multidrug-resistant Gram-negative bacteria carriage in children screened prospectively for multidrug resistant organisms at admission to a paediatric hospital, Hamburg, Germany, September 2018 to May 2019

Background

Increasing resistance to antibiotics poses medical challenges worldwide. Prospective data on carriage prevalence of multidrug resistant organisms (MDRO) in children at hospital admission are limited and associated risk factors are poorly defined.

Aim

To determine prevalence of MDRO carriage in children at admission to our paediatric hospital in Hamburg and to identify MDRO carriage risk factors.

Methods

We prospectively obtained and cultured nasal/throat and inguinal/anal swabs from children (≤ 18 years) at admission between September 2018 and May 2019 to determine prevalence of meticillin-resistant Staphylococcus aureus (MRSA), multidrug-resistant Gram-negative bacteria (MRGN) and vancomycin-resistant enterococcus (VRE) and associated species. We collected medical histories using a questionnaire and evaluated 31 risk factors using logistic regression models.

Results

MDRO carriage prevalence of 3,964 children was 4.31% (95% confidence interval (CI): 3.69–5.00). MRSA carriage prevalence was 0.68% (95% CI: 0.44–0.99), MRGN prevalence was 3.64% (95% CI: 3.07–4.28) and VRE prevalence 0.08% (95% CI: 0.02–0.22). MDRO carriage was associated with MRGN history (odds ratio (OR): 6.53; 95% CI: 2.58–16.13), chronic condition requiring permanent care (OR: 2.67; 95% CI: 1.07–6.13), antibiotic therapy (OR: 1.92, 95% CI: 1.24–2.94), living in a care facility (OR: 3.34; 95% CI: 0.72–12.44) and refugee status in previous 12 months (OR: 1.91; 95% CI: 0.27–8.02). Compared to established practice, screening using risk-factors had better diagnostic sensitivity (86.13%; 95% CI: 80.89–91.40) and specificity (73.54%; 95% CI: 72.12–74.97).

Conclusion

MRGN carriage was higher than MRSA and VRE. Extended risk-factor-based admission screening system seems warranted.

Improving Vancomycin Stewardship in Critically Ill Children

BACKGROUND AND OBJECTIVES

Inappropriate vancomycin use is common in children's hospitals. We report a quality improvement (QI) intervention to reduce vancomycin use in our tertiary care PICU.

METHODS

We retrospectively quantified the prevalence of infections caused by organisms requiring vancomycin therapy, including methicillin-resistant Staphylococcus aureus (MRSA), among patients with suspected bacterial infections. Guided by these data, we performed 3 QI interventions over a 3-year period, including (1) stakeholder education, (2) generation of a consensus-based guideline for empiric vancomycin use, and (3) implementation of this guideline through clinical decision support. Vancomycin use in days of therapy (DOT) per 1000 patient days was measured by using statistical process control charts. Balancing measures included frequency of bacteremia due to an organism requiring vancomycin not covered with empiric therapy, 30-day mortality, and cardiovascular, respiratory, and renal organ dysfunction.

RESULTS

Among 1276 episodes of suspected bacterial infection, a total of 19 cases of bacteremia (1.5%) due to organisms requiring vancomycin therapy were identified, including 6 MRSA bacteremias (0.5%). During the 3-year QI project, overall vancomycin DOT per 1000 patient days in the PICU decreased from a baseline mean of 182 DOT per 1000 patient days to 109 DOT per 1000 patient days (a 40% reduction). All balancing measures were unchanged, and all cases of MRSA bacteremia were treated empirically with vancomycin.

CONCLUSION

Our interventions reduced overall vancomycin use in the PICU without evidence of harm. Provider education and consensus building surrounding indications for empiric vancomycin use were key strategies.

Aligning Provider Prescribing With Guidelines for Soft Tissue Infections

OBJECTIVE

Despite evidence-based guidelines, antibiotics prescribed for uncomplicated skin and soft tissue infections can involve inappropriate microbial coverage. Our aim was to evaluate the appropriateness of antibiotic prescribing practices for mild nonpurulent cellulitis in a pediatric tertiary academic medical center over a 1-year period.

METHODS

Eligible patients treated in the emergency department or urgent care settings for mild nonpurulent cellulitis from January 2017 to December 2017 were identified by an International Classification of Diseases, Tenth Revision, code for cellulitis. The primary outcome was appropriateness of prescribed antibiotics as delineated by adherence with the Infectious Diseases Society of America guidelines. Secondary outcomes include reutilization rate as defined by revisit to the emergency department/urgent cares within 14 days of the initial encounter.

RESULTS

A total of 967 encounters were evaluated with 60.0% overall having guideline-adherent care. Common reasons for nonadherence included inappropriate coverage of MRSA with clindamycin (n = 217, 56.1%) and single-agent coverage with sulfamethoxazole-trimethoprim (n = 129, 33.3%). There were 29 revisits within 14 days of initial patient encounters or a reutilization rate of 3.0%, which was not significantly associated with the Infectious Diseases Society of America adherence.

CONCLUSIONS

Our data show antibiotic prescription for nonpurulent cellulitis as a potential area of standardization and optimization of care at our center.

Management and Prevention of Staphylococcus aureus Infections in Children

Staphylococcus aureus is a common skin commensal with the potential to cause severe infections resulting in significant morbidity and mortality. Up to 30% of individuals are colonized with S aureus, though infection typically does not occur without skin barrier disruption. Infection management includes promptly addressing the source of infection, including sites of metastatic infection, and initiation of effective antibiotics, which should be selected based on local antibiotic susceptibility patterns. Given that S aureus colonization is a risk factor for infection, preventive strategies are aimed at optimizing hygiene measures and decolonization regimens for outpatients and critically ill children with prolonged hospitalizations.

Differences Between Methicillin-susceptible Versus Methicillin-resistant Staphylococcus aureus Infections in Pediatrics: Multicenter Cohort Study Conducted in Bogotá, Colombia, 2014-2018

BACKGROUND

The epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-susceptible S. aureus (MSSA) has changed in recent years. The present article is intended to establish differences between clinical, laboratory and imaging findings and outcomes of MSSA and MRSA infections, as well as among subgroups of infection such as skin and soft tissue infection, osteoarticular, bacteremia or pneumonia in a pediatric population from Bogota, Colombia.

METHODS

Retrospective cohort study using clinical records of patients under 18 years of age treated at the participating centers in Bogota, Colombia, between 2014 and 2018. The first positive S. aureus culture was studied. MSSA and MRSA were compared. The χ2 test, Fisher exact test, and Kruskal-Wallis test were calculated, and the statistical significance was presented using the difference and its 95% CI.

RESULTS

Five hundred fifty-one patients were included; 211 (38%) corresponded to MRSA and 340 (62%) to MSSA for a total of 703 cultures. A significantly higher probability of having an MSSA infection than MRSA was found in patients with previous heart disease (3.3% vs. 0.5%), neurologic disease (5.9% vs. 2.5%), recent major surgeries (11% vs. 5%) or who has an implanted device (11% vs. 4%). In contrast, in severe MRSA infections (bacteremia, osteoarticular infections and pneumonia), a higher rate of complications was seen (admission to the pediatric intensive care unit, mechanical ventilation and vasoactive support), and in osteoarticular MRSA, more than 1 surgery per case was seen (89% vs. 61%). Laboratory results and mortality were similar.

CONCLUSIONS

MRSA was associated with a more severe course in bacteremia, osteoarticular infections and pneumonia. Some classical risk factors associated with MRSA infections were found to be related to MSSA. In general, with the exception of skin and soft tissue infection, there was an increased risk of pediatric intensive care unit admission and mechanical and inotropic support with MRSA in a pediatric population.

Clonal Distribution and Antibiotic Susceptibility of Staphylococcus aureus from Pediatric Patients: 8-Year Trends in a Children's Hospital in Colombia

Emergence of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) strains in healthcare settings has changed the hospital epidemiology of MRSA in the last few years. Despite a global increase in MRSA frequency, infections caused by methicillin-susceptible S. aureus (MSSA) have persisted in healthcare settings and the community. Staphylococcus aureus isolates were collected between 2009 and 2017 at the Children's Hospital of a Caribbean city in South America. Methicillin-resistant isolates were subjected to SCCmec typing. Representative isolates were analyzed by multilocus sequence typing (MLST) and spa typing. Antibiotic susceptibility was assessed by agar dilution method. D-zone test was performed in erythromycin-resistant isolates to determine macrolide/lincosamide/streptogramin resistance. Spa typing revealed 10 different spa types. The main epidemic clones circulating during the study period were: ST8-MRSA-IVc, ST923-MRSA-IVa and ST8-MRSA-IVa. The study found high frequencies of PVL genes and resistance to erythromycin and clindamycin in the isolates. This study provides the first description of the population structure of MRSA and MSSA causing infections attended in the participating Children's Hospital. ST8-MRSA-IVc, ST923-MRSA-IVa and ST8-MRSA-IVa were the most prevalent in the isolate population.

Quantifying Empiric Antibiotic Use in US Children's Hospitals

OBJECTIVES

Empirical broad-spectrum antibiotics are routinely administered for short durations to children with suspected bacteremia while awaiting blood culture results. Our aim for this study was to estimate the proportion of broad-spectrum antibiotic use accounted for by these "rule-outs."

METHODS

The Pediatric Health Information System was used to identify children aged 3 months to 20 years hospitalized between July 2016 and June 2017 who received broad-spectrum antibiotics for suspected bacteremia. Using an electronic definition for a rule-out, we estimated the proportion of all broad-spectrum antibiotic days of therapy accounted for by this indication. Clinical and demographic characteristics, as well as antibiotic choice, are reported descriptively.

RESULTS

A total of 67 032 episodes of suspected bacteremia across 42 hospitals were identified. From these, 34 909 (52%) patients were classified as having received an antibiotic treatment course, and 32 123 patients (48%) underwent an antibiotic rule-out without a subsequent treatment course. Antibiotics prescribed for rule-outs accounted for 12% of all broad-spectrum antibiotic days of therapy. Third-generation cephalosporins and vancomycin were the most commonly prescribed antibiotics, and substantial hospital-level variation in vancomycin use was identified (range: 16%-58% of suspected bacteremia episodes).

CONCLUSIONS

Broad-spectrum intravenous antibiotic use for rule-out infections appears common across children's hospitals, with substantial hospital-level variation in the use of vancomycin in particular. Antibiotic stewardship programs focused on intervening on antibiotics prescribed for longer durations may consider this novel opportunity to further standardize antibiotic regimens and reduce antibiotic exposure.

Pediatric osteoarticular infection: trend in surgically treated patients and association of methicillin-resistant Staphylococcus aureus with requirement of secondary procedures

Acute pediatric osteoarticular infection demonstrates variability in both presentation and response to treatment. Many respond to antibiotics ± single operation, while some require multiple surgeries. Currently, it is difficult to predict who may require additional procedures. Infections due to methicillin-resistant Staphylococcus aureus (MRSA) have been associated with more complications. The purpose of this study is to determine MRSA trends and degree of association with the occurrence of multiple procedures. We performed a retrospective analysis of surgically treated pediatric (1 month-18 years) patients for acute osteomyelitis and septic arthritis at a tertiary children's hospital from 2003-2017. The cohort was divided into single-procedure and multiple-procedure groups. A total of 753 patients were studied with a mean age of 7.05 years (2.4 months-17.9 years). We identified 645/753 (85.6%) patients who were treated with a single-procedure and 108/753 (14.4%) patients who required multiple- procedures. The lower extremity (hip, knee, tibia, and femur) was most commonly involved. The epidemiologic trend runs almost parallel between two groups with a peak in 2009. The odds ratio for multiple-procedures was 2.0 [95% confidence interval (CI), 1.2-3.1; P = 0.002] with dual infection (osteomyelitis + septic arthritis), 2.6 (95% CI, 1.6-4.4; P = 0.001) with high-risk conditions and 4.6 (95% CI, 3.0-7.1; P < 0.001) if MRSA was present. MRSA significantly predicts the requirement of additional operative procedures for the treatment of osteoarticular infections in children. Besides clinical deterioration and other markers, the presence of MRSA can be a considerable indicator for a planned secondary-procedure. Level III retrospective cohort study.

Clonal Diversity and Molecular Characteristics of Methicillin-Susceptible and -Resistant Staphylococcus aureus from Pediatric Patients in Myanmar

The spread of multidrug-resistant and virulent Staphylococcus aureus among children is a public health concern, but the actual conditions in Myanmar have not been characterized. In this study, a total of 244 clinical isolates of S. aureus collected from pediatric patients in Yangon Children's Hospital during a 1-year period were analyzed for their drug resistance and genetic features. Methicillin-resistant S. aureus (MRSA) accounted for 19.7% of isolates associated with staphylococcal cassette chromosome mec (SCCmec) type III, IV, or V. Panton-Valentine leukocidin (PVL) genes were detected in 61.5% of all isolates, with a significantly higher prevalence in methicillin-susceptible S. aureus (MSSA; 67.9%) than in MRSA (35.4%) isolates. Sequence type (ST) 239/SCCmec-III was the most common MRSA clone lacking PVL genes, while PVL-positive MRSA belonged to mostly ST361/SCCmec-V and ST772/SCCmec-V. Among MSSA isolates, ST121, ST2990, ST88, and ST1930 were dominant, harboring mostly PVL genes. ST239 MRSA isolates exhibited the highest resistance rates to antimicrobials, and quinolone resistance was found in the dominant MRSA clones (ST239, ST361, and ST772) and some MSSA lineages. The present study revealed the prevalence and clonal diversity of MRSA/MSSA in children in Myanmar in relation to drug resistance and virulence determinants.

Staphylococcus aureus infections in children

PURPOSE OF REVIEW

Staphylococcus aureus is the most common invasive bacterial pathogen infecting children in the U.S. and many parts of the world. This major human pathogen continues to evolve, and recognition of recent trends in epidemiology, therapeutics and future horizons is of high importance.

RECENT FINDINGS

Over the past decade, a relative rise of methicillin-susceptible S. aureus (MSSA) has occurred, such that methicillin-resistant S. aureus (MRSA) no longer dominates the landscape of invasive disease. Antimicrobial resistance continues to develop, however, and novel therapeutics or preventive modalities are urgently needed. Unfortunately, several recent vaccine attempts proved unsuccessful in humans.

SUMMARY

Recent scientific breakthroughs highlight the opportunity for novel interventions against S. aureus by interfering with virulence rather than by traditional antimicrobial mechanisms. A S. aureus vaccine remains elusive; the reasons for this are multifactorial, and lessons learned from prior unsuccessful attempts may create a path toward an effective preventive. Finally, new diagnostic modalities have the potential to greatly enhance clinical care for invasive S. aureus disease in children.

Risk factors for surgical site infection in pediatric posterior fossa tumors

PURPOSE

Posterior fossa tumors are the most frequent pediatric solid tumor. Its main treatment is a surgical resection. Being a frequent procedure does not mean that it is exempt from complications, such as surgical site infections (SSI). The main objective of this paper is to study the risk factors associated with SSI following a resection of posterior fossa tumors in a purely pediatric population.

METHODS

A retrospective case-control study including all posterior fossa tumor surgeries performed at our hospital between January 2014 and December 2019 was conducted. All patients with a diagnosis of a postoperative SSI have been included as cases, and those who had surgery and no infectious complications have been considered as controls.

RESULTS

When analyzing risk factors, we have found that patients with ventriculoperitoneal shunt (VPS) (p = 0.03) or external ventricular drainage (EVD) (p = 0.005) placement had a greater chance of presenting a postoperative surgical site infection. Prolonged operative time (p < 0.001) and cerebrospinal fluid (CSF) leak through the wound (p = 0.002) also caused an increase in the risk of SSI in the postoperative period. A higher hemoglobin value (p = 0.002) would seem to be a preventive factor.

CONCLUSIONS

Some strategies that could help to reduce the risk of infections are managing hydrocephalus preferably with endoscopic third ventriculostomy, minimizing the needed operative time to perform the procedure, obtaining an adequate serum hemoglobin level, and avoiding CSF leak through the wound.

Pediatric impetigo: an expert panel opinion about its main controversies

Bacterial impetigo is one of the most common skin infection in childhood. Uncertainty exists about its management. This article offers practical suggestions, given the existing evidence and experts' opinions, for correctly managing pediatric impetigo in both hospital and ambulatory settings. Italian physicians with an expertise on pediatric impetigo appointed a working group. A preliminary literature search using Pubmed/MEDLINE and Cochrane Library databases has been performed. The most common controversial issues about pediatric impetigo have been identified and then discussed from multidisciplinary perspectives, according to the 'structured controversy' methodology, a technique discovered and designed to get engaged in a controversy and then guide participants to seek consensus. The expert panels identified 10 main controversies about pediatric impetigo. All of them have been discussed from dermatological, pediatric, pharmacological and microbiological points of view reaching consensus. Each controversy has been revised thus giving practical issues for an easy use in clinical practice. Based on clinical experts' opinion, local epidemiology and literature review this article offers practical suggestions for the management of pediatric impetigo trying to reduce uncertainty in this setting of care.

Clinical Epidemiology and Outcomes of Pediatric Musculoskeletal Infections

OBJECTIVES

To understand the epidemiology of acute hematogenous osteomyelitis and septic arthritis, including clinical and demographic features, microbiology, treatment approaches, treatment-associated complications, and outcomes.

STUDY DESIGN

Retrospective cohort study of 453 children with acute hematogenous osteomyelitis and/or septic arthritis from 2009 to 2015.

RESULTS

Among the 453 patients, 218 (48%) had acute hematogenous osteomyelitis, 132 (29%) had septic arthritis, and 103 (23%) had concurrent acute hematogenous osteomyelitis/septic arthritis. Treatment failure/recurrent infection occurred in 41 patients (9%). Patients with concurrent acute hematogenous osteomyelitis/septic arthritis had longer hospital stays, longer duration of antibiotic therapy, and were more likely to have prolonged bacteremia and require intensive care. Staphylococcus aureus was identified in 228 (51%) patients, of which 114 (50%) were methicillin-resistant S aureus. Compared with septic arthritis, acute hematogenous osteomyelitis and concurrent acute hematogenous osteomyelitis/septic arthritis were associated with higher odds of treatment failure (OR, 8.19; 95% CI, 2.02-33.21 [P = .003]; and OR, 14.43; 95% CI, 3.39-61.37 [P < .001], respectively). The need for more than 1 surgical procedure was also associated with higher odds of treatment failure (OR, 2.98; 95% CI, 1.18-7.52; P = .021). Early change to oral antibiotic therapy was not associated with treatment failure (OR, 0.64; 95% CI, 0.24-1.74; P = .386). Most (73%) medically attended treatment complications occurred while on parenteral therapy.

CONCLUSIONS

Musculoskeletal infections are challenging pediatric infections. S aureus remains the most common pathogen, with methicillin-resistant S aureus accounting for 25% of all cases. Concurrent acute hematogenous osteomyelitis/septic arthritis is associated with more severe disease and worse outcomes. Fewer treatment-related complications occurred while on oral therapy. Early transition to oral therapy was not associated with treatment failure.

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.

Adoptive Transfer of Serum Samples From Children With Invasive Staphylococcal Infection and Protection Against Staphylococcus aureus Sepsis

A successful Staphylococcus aureus vaccine remains elusive, and one controversy in the field is whether humans generate a protective adaptive immune response to infection. We developed a bacterial challenge murine assay that directly assesses the protective capacity of adoptively transferred human serum samples. We first validated the model by showing that postpneumococcal vaccine serum samples from humans induced effective clearance of Streptococcus pneumoniae in mice. We then found that human serum samples adoptively transferred from children with invasive S. aureus infections exhibited protection from disease in a murine model, with some samples conferring near complete protection. These findings demonstrate that human serum samples are capable of conferring a protective adaptive response generated by humans during invasive staphylococcal disease, allowing for the study of protective factors in a murine model. Identification of the protective factors present in the most efficacious serum samples would be of high interest as potential staphylococcal vaccine candidates or passive therapeutics.

Antibiotic Resistance in Pediatric Infections: Global Emerging Threats, Predicting the Near Future

Antibiotic resistance is a public health threat of the utmost importance, especially when it comes to children: according to WHO data, infections caused by multidrug resistant bacteria produce 700,000 deaths across all ages, of which around 200,000 are newborns. This surging issue has multipronged roots that are specific to the pediatric age. For instance, the problematic overuse and misuse of antibiotics (for wrong diagnoses and indications, or at wrong dosage) is also fueled by the lack of pediatric-specific data and trials. The ever-evolving nature of this age group also poses another issue: the partly age-dependent changes of a developing system of cytochromes determine a rather diverse population in terms of biochemical characteristics and pharmacokinetics profiles, hard to easily codify in an age- or weight-dependent dosage. The pediatric population is also penalized by the contraindications of tetracyclines and fluoroquinolones, and by congenital malformations which often require repeated hospitalizations and pharmacological and surgical treatments from a very young age. Emerging threats for the pediatric age are MRSA, VRSA, ESBL-producing Enterobacteriaceae, carbapenem-resistant Enterobacteriaceae and the alarming colistin resistance. Urgent actions need to be taken in order to step back from a now likely post-antibiotic era, where simple infections might cause infant death once again.

Safety and Efficacy of Oral and/or Intravenous Tedizolid Phosphate From a Randomized Phase 3 Trial in Adolescents With Acute Bacterial Skin and Skin Structure Infections

BACKGROUND

Tedizolid phosphate is an oxazolidinone prodrug approved in 2014 for treatment of adults with acute bacterial skin and skin structure infections (ABSSSIs); however, efficacy has not previously been evaluated in children. This study compared the safety and efficacy of tedizolid (administered as tedizolid phosphate) with active antibacterial comparators for the treatment of ABSSSIs in adolescents.

METHODS

This was a randomized, assessor-blind, global phase 3 study of tedizolid versus active comparators for the treatment of Gram-positive ABSSSIs in adolescents (12 to <18 years of age; NCT02276482). Enrolled participants were stratified by region and randomized 3:1 to receive tedizolid phosphate 200 mg (oral and/or intravenous) once daily for 6 days or active comparator, selected by investigator from an allowed list per local standard of care, for 10 days. The primary endpoint was safety; blinded investigator's assessment of clinical success at the test-of-cure visit (18-25 days after the first dose) was a secondary efficacy endpoint. Statistical comparisons between treatment groups were not performed.

RESULTS

Of the 121 participants enrolled, 120 were treated (tedizolid, n = 91; comparator, n = 29). Treatment-emergent adverse events were balanced between treatment groups (tedizolid, 14.3%; comparator, 10.3%). Overall, 3 participants (3.3%) in the tedizolid group and 1 (3.4%) in the comparator group experienced a single drug-related TEAE. Clinical success rates were high in both treatment groups: 96.7% and 93.1% at the test-of-cure visit for the tedizolid and comparator groups, respectively.

CONCLUSIONS

Tedizolid demonstrated safety and efficacy similar to comparators for the treatment of ABSSSIs in adolescents.

Genomic analysis revealed a novel genotype of methicillin-susceptible Staphylococcus aureus isolated from a fatal sepsis case in dengue patient

Staphylococcus aureus (S. aureus) is an opportunistic pathogen capable of causing serious health implications in susceptible individuals once it invades the host’s protective barriers. Methicillin-susceptible S. aureus (MSSA) often receives lesser attention although it has been frequently associated with serious infections in human. We aim to investigate the genomic features of a highly virulent yet pan susceptible MSSA strain (coded as HS-MSSA) which caused concurrent bacteraemia in a dengue patient, ultimately resulted in sepsis death of the patient. Whole genome sequence analysis was performed. The draft genome of HS-MSSA is approximately 2.78 Mb (GC content = 32.7%) comprising of 2637 predicted coding sequences. In silico genotyping of the HS-MSSA strain revealed a novel combined genotype (t091/ST2990). The HS-MSSA carries a SaPIn1-like pathogenicity island that harbours the staphylococcal enterotoxin and enterotoxin-like genes (sec3 and selL). The strain-specific β-lactamase (blaZ)-bearing plasmid region was identified in HS-MSSA. Core genome phylogeny showed that the HS-MSSA strain shared a common ancestry with the European MRSA clone. We report herein the genomic features of an MSSA lineage with novel genotype previously not reported elsewhere.

National Trends in Incidence of Purulent Skin and Soft Tissue Infections in Patients Presenting to Ambulatory and Emergency Department Settings, 2000-2015

Nationally representative data from 2000-2015 demonstrated a rise in the incidence of outpatient visits for skin infections, peaking in 2010-2013, followed by a plateau. While cephalexin was the most frequently prescribed antibiotic at the beginning, trimethoprim-sulfamethoxazole was most frequently prescribed by the end of the study period.

Optimizing the Use of Antibiotic Agents in the Pediatric Intensive Care Unit: A Narrative Review

Antibiotics are one of the most prescribed drug classes in the pediatric intensive care unit, yet the incidence of inappropriate antibiotic prescribing remains high in critically ill children. Optimizing the use of antibiotics in this population is imperative to guarantee adequate treatment, avoid toxicity and the occurrence of antibiotic resistance, both on a patient level and on a population level. Antibiotic stewardship encompasses all initiatives to promote responsible antibiotic usage and the PICU represents a major target environment for antibiotic stewardship programs. This narrative review provides a summary of the available knowledge on the optimal selection, duration, dosage, and route of administration of antibiotic treatment in critically ill children. Overall, more scientific evidence on how to optimize antibiotic treatment is warranted in this population. We also give our personal expert opinion on research priorities.

The infectious complications of atopic dermatitis

OBJECTIVE

Atopic dermatitis (AD) is a chronic inflammatory skin disease that is complicated by an increased risk for skin and systemic infections. Preventive therapy for AD is based on skin barrier improvement and anti-inflammatory treatments, whereas overt skin and systemic infections require antibiotics or antiviral treatments. This review updates the pathophysiology, diagnosis, management, controversy of antibiotic use, and potential treatments of infectious complications of AD.

DATA SOURCES

Published literature obtained through PubMed database searches and clinical pictures.

STUDY SELECTIONS

Studies relevant to the mechanisms, diagnosis, management, and potential therapy of infectious complications of AD.

RESULTS

Skin barrier defects, type 2 inflammation, Staphylococcusaureus colonization, and cutaneous dysbiosis are the major predisposing factors for the increased infections in AD. Although overt infections require antibiotics, the use of antibiotics in AD exacerbation remains controversial.

CONCLUSION

Infectious complications are a comorbidity of AD. Although not common, systemic bacterial infections and eczema herpeticum can be life-threatening. Preventive therapy of infections in AD emphasizes skin barrier improvement and anti-inflammatory therapy. The use of antibiotics in AD exacerbation requires further studies.

Staphylococcus aureus Nasal Colonization in Spanish Children. The COSACO Nationwide Surveillance Study

Objective

To assess the prevalence and risk factors for S. aureus and methicillin-resistant S. aureus (MRSA) nasal colonization in Spanish children.

Methods

Cross-sectional study of patients <14 years from primary care centers all over Spain. Clinical data and nasal aspirates were collected from March to July 2018.

Results

A total of 1876 patients were enrolled. Prevalence of S. aureus and MRSA colonization were 33% (95% CI 30.9–35.1) and 1.44% (95% CI 0.9–2), respectively. Thirty-three percent of the children (633/1876) presented chronic conditions, mainly atopic dermatitis, asthma and/or allergy (524/633). Factors associated with S. aureus colonization were age ≥5 years (OR 1.10, 95% CI 1.07–1.12), male sex (OR 1.43, 95% CI 1.17–1.76), urban setting (OR 1.46, 95% CI 1.08–1.97) and the presence of asthma, atopic dermatitis or allergies (OR 1.25; 95% CI: 1.093–1.43). Rural residence was the only factor associated with MRSA colonization (OR 3.62, 95% CI 1.57–8.36). MRSA was more frequently resistant than methicillin-susceptible S. aureus to ciprofloxacin [41.2% vs 2.6%; p<0.0001], clindamycin [26% vs 16.9%; p=0.39], and mupirocin [14.3% vs 6.7%; p=0.18]. None of the MRSA strains was resistant to tetracycline, fosfomycin, vancomycin or daptomycin.

Conclusions

The main risk factors for S. aureus colonization in Spanish children are being above five years of age, male gender, atopic dermatitis, asthma or allergy, and residence in urban areas. MRSA colonization is low, but higher than in other European countries and is associated with rural settings.

Antibiotic Resistance - A Cause for Reemergence of Infections

This article can rightly be called 'the rise of the microbial phoenix'; for, all the microbial infections whose doomsday was predicted with the discovery of antibiotics, have thumbed their noses at mankind and reemerged phoenix like. The hubris generated by Sir Alexander Fleming's discovery of Penicillin in 1928, exemplified best by the comment by William H Stewart, the US Surgeon General in 1967, "It is time to close the books on infectious diseases" has been replaced by the realisation that the threat of antibiotic resistance is, in the words of the Chief Medical Officer of England, Dame Sally Davies, "just as important and deadly as climate change and international terrorism". Antimicrobial resistance threatens to negate all the major medical advances of the last century because antimicrobial use is linked to many other fields like organ transplantation and cancer chemotherapy. Antibiotic resistance genes have been there since ancient times in response to naturally occurring antibiotics. Modern medicine has only driven further evolution of antimicrobial resistance by use, misuse, overuse and abuse of antibiotics. Resistant bacteria proliferate by natural selection when their drug sensitive comrades are removed by antibiotics. In this article the authors discuss the various causes of antimicrobial resistance and dwell in some detail on antibiotic resistance in gram-positive and gram-negative organisms. Finally they stress on the important role clinicians have in limiting the development and spread of antimicrobial resistance.

Microbiology and radiographic features of osteomyelitis in children and adolescents with sickle cell disease

BACKGROUND

Children with sickle cell disease (SCD) are at increased risk for bacterial infections including osteomyelitis (OM). Fever and bone pain, key presenting symptoms of OM, are common in SCD, thus complicating diagnosis. We reviewed presentation, imaging features, and microbiologic etiologies of children with SCD treated for OM.

METHODS

The comprehensive SCD clinical database of children and adolescents with SCD followed at a single, large tertiary pediatric center were searched to identify all diagnostic coding for potential cases of osteomyelitis in children ages 6 months to 21 years from 2010 to 2019. Medical charts were reviewed to determine OM diagnostic probability based on radiographic and microbiologic findings and the duration of prescribed antibiotic treatment for OM.

RESULTS

Review of 3553 patients (18 039 person-years) identified 20 episodes of probable OM in 19 children. Magnetic resonance imaging (MRI) findings to support OM were definitive in 4/19 (21%), probable in 10/19 (53%), suspected in 5/19 (26%), based on blinded radiologist review. Blood and/or operative cultures from bone and tissue debridement isolated Salmonella species in seven (35%) cases and methicillin-susceptible Staphylococcus aureus (MSSA) in two (10%). Six patients received antibiotic treatment prior to obtainment of cultures. Of culture-positive cases, MRI findings for OM were definitive or probable in six of nine (67%), suspected in three of nine (33%).

CONCLUSIONS

Distinction between OM and sickle-related bone infarct or vasoocclusion is difficult based on imaging findings alone. Early attainment of blood and operative cultures increases the likelihood of identifying and adequately treating OM.

Clinical and molecular epidemiology of invasive Staphylococcus aureus infection in Utah children; continued dominance of MSSA over MRSA

BACKGROUND

Invasive Staphylococcus aureus infections are a common cause of morbidity and mortality in children. In the early 2000's the proportion of infections due the methicillin-resistant S. aureus (MRSA) increased rapidly. We described the clinical and molecular epidemiology of invasive S. aureus disease in a pediatric population.

METHODS

We prospectively identified children in Utah with invasive S. aureus infections. Medical records were reviewed to determine diagnosis and clinical characteristics. Isolates were genotyped using multi-locus sequence typing. The presence of genes encoding the Panton-Valentine leukocidin (PVL) was determined using polymerase chain reaction.

RESULTS

Over a 4-year period between January 2009 and December 2012, we identified 357 children, hospitalized at Primary Children's Hospital, with invasive S. aureus infections and isolates available for the study. Methicillin-susceptible S. aureus (MSSA) caused 79% of disease, while MRSA caused only 21% of disease. Mortality associated with invasive S. aureus infection was 3.6%. The most common diagnoses were osteoarticular infections (38%) followed by central line associated blood stream infections (19%) and pneumonia (12%). We identified 41 multi-locus sequence types. The majority of isolates belonged to 6 predominant clonal complexes (CC5, CC8, CC15, CC30, CC45, CC59). PVL was present in a minority (16%) of isolates, of which most were ST8 MRSA.

CONCLUSIONS

MSSA was the primary cause of invasive S. aureus infections at our institution throughout the study period. A limited number of predominant strains accounted for the majority of invasive disease. The classic virulence factor PVL was uncommon in MSSA isolates. Further study is needed to improve our understanding of S. aureus virulence and disease pathogenesis.

Cefazolin Inoculum Effect and Methicillin-Susceptible Staphylococcus aureus Osteoarticular Infections in Children

Select methicillin-susceptible Staphylococcus aureus (MSSA) strains may produce β-lactamases with affinity for first-generation cephalosporins (1GCs). In the setting of a high inoculum, these β-lactamases may promote the cleavage of 1GCs, a phenomenon known as the cefazolin inoculum effect (CzIE). We evaluated the prevalence and impact of CzIE on clinical outcomes among MSSA acute hematogenous osteomyelitis (AHO) cases. MSSA AHO isolates obtained from two children's hospitals between January 2011 and December 2018 were procured through ongoing surveillance studies. Isolates were tested for CzIE via a broth macrodilution assay using an inoculum of 10⁷ CFU/ml; CzIE was defined as a cefazolin MIC of ≥16 μg/ml. Isolates were characterized by accessory gene regulator group (agr). The progression from acute to chronic osteomyelitis was considered an important outcome. A total of 250 cases with viable isolates were included. Notably, 14.4% of isolates exhibited CzIE with no observed temporal trend; and 4% and 76% of patients received a 1GC as an empirical and definitive therapy, respectively. CzIE isolates were more often resistant to clindamycin, belonged to agrIII, and associated with the development of chronic osteomyelitis. In multivariable analyses, agrIII, multiple surgical debridements, delayed source control, and CzIE were independently associated with progression to chronic osteomyelitis. A higher rate of chronic osteomyelitis was observed with CzIE isolates regardless of definitive antibiotic choice. CzIE is exhibited by 14.4% of MSSA AHO isolates in children. CzIE is independently associated with progression to chronic osteomyelitis in cases of AHO irrespective of final antibiotic choice. These data suggest that negative outcomes reported with CzIE may more accurately reflect strain-dependent virulence factors rather than true antibiotic failure.

Amoxicillin-Clavulanic Acid Empirical Oral Therapy for the Management of Children with Acute Haematogenous Osteomyelitis

According to the Guidelines of the European Society of Pediatric Infectious Diseases (ESPID), in low methicillin-resistant Staphylococcus aureus (MRSA) prevalence settings, short intravenous therapy is recommended in uncomplicated cases of acute haematogenous osteomyelitis (AHOM), followed by empirical oral therapy, preferentially with first/second-generation cephalosporin or dicloxacillin or flucloxacillin. However, several practical issues may arise using some of the first-line antibiotics such as poor palatability or adherence problems. Clinical, laboratory and therapeutic data from children with AHOM hospitalized in one Italian Paediatric Hospital between 2010 and 2019 were retrospectively collected and analyzed. The aim of the study was to highlight the extent of the use and the possible role of amoxicillin-clavulanic acid in the oral treatment of children with AHOM. Two hundred and ten children were included. S.aureus was identified in 42/58 children (72.4% of identified bacteria); 2/42 S.aureus isolates were MRSA (4.8%). No Kingella kingae was identified. Amoxicillin-clavulanic acid was the most commonly used oral drug (60.1%; n = 107/178) and it was associated with clinical cure in all treated children. Overall, four children developed sequelae. One (0.9%) sequela occurred among the 107 children treated with amoxicillin-clavulanic acid. Our results suggest that amoxicillin-clavulanic acid might be an option for oral antibiotic therapy in children with AHOM.

Vancomycin Therapeutic Drug Monitoring in Children: New Recommendations, Similar Challenges

The American Society of Health-System Pharmacists, the Infectious Diseases Society of America, the Pediatric Infectious Diseases Society, and the Society of Infectious Diseases Pharmacists have recently published revised guidelines for the therapeutic monitoring of vancomycin. Previous iterations of the guideline largely focused on targeting vancomycin trough concentrations (VTCs) in the range of 15 to 20 mg/L for therapeutic efficacy. The revised guidelines shift the focus of therapeutic monitoring directly to AUC/MIC-based therapeutic monitoring for children, with a suggestion of a goal AUC/MIC 400 to 800. The primary hesitation in applying these recommendations to children stems from the absence of pediatric clinical data demonstrating correlations with clinical outcomes and either VTC or AUC and no benefit in other secondary outcomes (e.g., recurrence, duration of bacteremia). One can glean indirectly from this that such aggressive dosing and monitoring strategies are unnecessary to achieve therapeutic success in the majority of children with serious methicillin-resistant Staphylococcus aureus infections. Providers should carefully weigh the potential unknown benefits of targeting vancomycin AUC 400 to 800 mg*hr/L in children with the known risks of acute kidney injury associated with increasing the dose of vancomycin as well as the substantial time, effort, and costs of this process.

Current Epidemiology, Etiology, and Burden of Acute Skin Infections in the United States

The US burden of acute skin infections is substantial. While Staphylococcus aureus and Streptococcus spp. are the most common causes, gram-negative bacteria and mixed infections can occur in some settings. These mixed infections are more likely to result in inappropriate empiric antibiotic therapy. Important challenges remain in diagnosing and treating acute skin infections.