Comparative effectiveness of antibiotic treatment strategies for pediatric skin and soft-tissue infections

''Myth Busting in Infectious Diseases'': A Comprehensive Review

Antibiotics have played a pivotal role in modern medicine, drastically reducing mortality rates associated with bacterial infections. Despite their significant contributions, the emergence of antibiotic resistance has become a formidable challenge, necessitating a re-evaluation of antibiotic use practices. The widespread belief in clinical practice that bactericidal antibiotics are inherently superior to bacteriostatic ones lacks consistent support from evidence in randomized controlled trials (RCTs). With the latest evidence, certain infections have demonstrated equal or even superior efficacy with bacteriostatic agents. Furthermore, within clinical practice, there is a tendency to indiscriminately order urine cultures for febrile patients, even in cases where alternative etiologies might be present. Consequently, upon obtaining a positive urine culture result, patients often receive antimicrobial prescriptions despite the absence of clinical indications warranting such treatment. Furthermore, it is a prevailing notion among physicians that extended durations of antibiotic therapy confer potential benefits and mitigate the emergence of antimicrobial resistance. Contrary to this belief, empirical evidence refutes such assertions. This article aims to address common myths and misconceptions within the field of infectious diseases.

Antibiotic susceptibility and clonal distribution of Staphylococcus aureus from pediatric skin and soft tissue infections: 10-year trends in multicenter investigation in China

Background

Skin and Soft Tissue Infections (SSTIs) Surveillance Network of S. aureus In Pediatrics in China was established in 2009 to routinely report epidemiological changes. We aimed to monitor the present antibiotic sensitivity and molecular characteristics of S. aureus and methicillin-resistant S. aureus (MRSA) from SSTIs in children nationwide and track the changes over the past decade.

Methods

Patients diagnosed with SSTIs from the dermatology departments of 22 tertiary pediatric hospitals in seven geographical regions of China were recruited continuously from May 2019 to August 2021. S. aureus was isolated, and its sensitivity to 15 antimicrobials was evaluated using the broth microdilution method. The molecular characteristics of the MRSA isolates were determined through multilocus sequence typing (MLST) and staphylococcal cassette chromosome mec (SCCmec) typing. The presence of the Panton-Valentine leukocidin gene (pvl) was determined.

Results

The detection rate of S. aureus was 62.57% (1379/2204), among which MRSA accounted for 14.79% (204/1379), significantly higher than the result in previous study in 2009-2011 (2.58%, 44/1075). Compared with previous study, the sensitivity to cephalosporins and fusidic acid decreased to varying degrees, while that to chloramphenicol, ciprofloxacin, clindamycin, erythromycin, gentamicin, penicillin, and tetracycline increased significantly. The sensitivity to mupirocin, trimethoprim/sulfamethoxazole (TRISUL), and rifampicin still maintained at a high level (97.90%, 99.35% and 96.66% respectively). The leading multidrug resistance pattern of MRSA and methicillin-sensitive S. aureus (MSSA) were erythromycin-clindamycin-tetracycline (55.84%; 43/77) and erythromycin-clindamycin-chloramphenicol (27.85%, 44/158) respectively. 12 high-level mupirocin-resistant strains were detected, and notable differences in geographical distribution and seasonal variation were observed. The main types of MRSA were ST121 (46.08%, 94/204), followed by ST59 (19.61%, 40/204). SCCmec V (65.69%, 134/204) and SCCmec IV (31.86%, 65/204) were dominant epidemic types. ST121-V, ST59-IV, and ST22-V were the most prevalent clones nationwide. The detection rate of pvl had increased markedly from 9.09% (4/44) in 2009-2011 to 22.55% (46/204) in 2019-2021 (P<0.05).

Conclusion

The antibiotic sensitivity and molecular characteristics of S. aureus from pediatric SSTIs has changed significantly over the past decade. To standardize medical care, provide timely and reasonable clinical treatment, and effectively manage infection control, Chinese pediatric SSTIs guidelines are urgently needed.

Variation in Antibiotic Treatment Failure Outcome Definitions in Randomised Trials and Observational Studies of Antibiotic Prescribing Strategies: A Systematic Review and Narrative Synthesis

Antibiotic treatment failure is used as an outcome in randomised trials and observational studies of antibiotic treatment strategies and may comprise different events that indicate failure to achieve a desired clinical response. However, the lack of a universally recognised definition has led to considerable variation in the types of events included. We undertook a systematic review of published studies investigating antibiotic treatment strategies for common uncomplicated infections, aiming to describe variation in terminology and components of the antibiotic treatment failure outcomes. We searched Medline, Embase, and the Cochrane Central Register of Clinical trials for English language studies published between January 2010 and January 2021. The population of interest was ambulatory patients seen in primary care or outpatient settings with respiratory tract (RTI), urinary tract (UTI), or skin and soft tissue infection (SSTI), where different antibiotic prescribing strategies were compared, and the outcome was antibiotic treatment failure. We narratively summarised key features from eligible studies and used frequencies and proportions to describe terminology, components, and time periods used to ascertain antibiotic treatment failure outcomes. Database searches identified 2967 unique records, from which 36 studies met our inclusion criteria. This included 10 randomised controlled trials and 26 observational studies, with 20 studies of RTI, 12 of UTI, 4 of SSTI, and 2 of both RTI and SSTI. We identified three key components of treatment failure definitions: prescription changes, escalation of care, and change in clinical condition. Prescription changes were most popular in studies of UTI, while changes in clinical condition were most common in RTI and SSTI studies. We found substantial variation in the definition of antibiotic treatment failure in included studies, even amongst studies of the same infection subtype and study design. Considerable further work is needed to develop a standardised definition of antibiotic treatment failure in partnership with patients, clinicians, and relevant stakeholders.

Invasive Bacterial Infections in Infants Younger Than 60 Days With Skin and Soft Tissue Infections

OBJECTIVE

The objective of this study was to describe the frequency of invasive bacterial infections (IBIs) in young infants with skin and soft tissue infections (SSTIs) and the impact of IBI evaluation on disposition, length of stay (LOS), and cost.

METHODS

This retrospective (2009-2014) cohort study used data from 35 children's hospitals in the Pediatric Health Information System. We included infants younger than 60 days who presented to an emergency department (ED) with SSTI. Invasive bacterial infection was defined as bacteremia/sepsis, bone/joint infection, or bacterial meningitis. Readmission and return ED visits within 30 days were evaluated to identify missed IBIs for infants.

RESULTS

A total of 2734 infants were included (median age, 33 days; interquartile range [IQR], 21-44); 62% were hospitalized. Invasive bacterial infection was identified in 2%: bacteremia (1.8%), osteomyelitis (0.1%), and bacterial meningitis (0.1%). Hospitalization occurred in 78% of infants with blood cultures, 95% with cerebrospinal fluid cultures, and 23% without cultures. Median hospitalization LOS was 2 days (IQR, 1-3). Median cost was US $4943 for infants with cerebrospinal fluid cultures (IQR, US $3475-6780) compared with US $419 (IQR, US $215-1149) for infants without IBI evaluations (P < 0.001). Five infants (0.2%) returned to the ED within 30 days with new IBI diagnoses (4 bacteremia, 1 meningitis).

CONCLUSIONS

Invasive bacterial infection occurs infrequently in infants younger than 60 days who present to children's hospital EDs with SSTI. Bacteremia is the most common IBI. More extensive evaluation for IBI is associated with increased rate of admission, LOS, and cost. Further studies are needed to evaluate the safety of a limited IBI evaluation in young infants with SSTI.

IBT-V02: A Multicomponent Toxoid Vaccine Protects Against Primary and Secondary Skin Infections Caused by Staphylococcus aureus

Staphylococcus aureus causes a wide range of diseases from skin infections to life threatening invasive diseases such as bacteremia, endocarditis, pneumonia, surgical site infections, and osteomyelitis. Skin infections such as furuncles, carbuncles, folliculitis, erysipelas, and cellulitis constitute a large majority of infections caused by S. aureus (SA). These infections cause significant morbidity, healthcare costs, and represent a breeding ground for antimicrobial resistance. Furthermore, skin infection with SA is a major risk factor for invasive disease. Here we describe the pre-clinical efficacy of a multicomponent toxoid vaccine (IBT-V02) for prevention of S. aureus acute skin infections and recurrence. IBT-V02 targets six SA toxins including the pore-forming toxins alpha hemolysin (Hla), Panton-Valentine leukocidin (PVL), leukocidin AB (LukAB), and the superantigens toxic shock syndrome toxin-1 and staphylococcal enterotoxins A and B. Immunization of mice and rabbits with IBT-V02 generated antibodies with strong neutralizing activity against toxins included in the vaccine, as well as cross-neutralizing activity against multiple related toxins, and protected against skin infections by several clinically relevant SA strains of USA100, USA300, and USA1000 clones. Efficacy of the vaccine was also shown in non-naïve mice pre-exposed to S. aureus. Furthermore, vaccination with IBT-V02 not only protected mice from a primary infection but also demonstrated lasting efficacy against a secondary infection, while prior challenge with the bacteria alone was unable to protect against recurrence. Serum transfer studies in a primary infection model showed that antibodies are primarily responsible for the protective response.

Antibiotic Regimens and Associated Outcomes in Children Hospitalized With Staphylococcal Scalded Skin Syndrome

BACKGROUND

Controversy exists regarding the optimal antibiotic regimen for use in hospitalized children with staphylococcal scalded skin syndrome (SSSS). Various regimens may confer toxin suppression and/or additional coverage for methicillin-susceptible Staphylococcus aureus (MSSA) or methicillin-resistant S aureus (MRSA).

OBJECTIVES

To describe antibiotic regimens in hospitalized children with SSSS and examine the association between antistaphylococcal antibiotic regimens and patient outcomes.

DESIGN/METHODS

Retrospective cohort study of children hospitalized with SSSS using the Pediatric Health Information System database (2011-2016). Children who received clindamycin monotherapy, clindamycin plus MSSA coverage (eg, nafcillin), or clindamycin plus MRSA coverage (eg, vancomycin) were included. The primary outcome was hospital length of stay (LOS); secondary outcomes were treatment failure and cost. Generalized linear mixed-effects models were used to compare outcomes among antibiotic groups.

RESULTS

Of 1,259 children included, 828 children received the most common antistaphylococcal antibiotic regimens: clindamycin monotherapy (47%), clindamycin plus MSSA coverage (33%), and clindamycin plus MRSA coverage (20%). Children receiving clindamycin plus MRSA coverage had higher illness severity (44%) compared with clindamycin monotherapy (28%) and clindamycin plus MSSA (32%) (P =.001). In adjusted analyses, LOS and treatment failure did not differ among the 3 regimens (P =.42 and P =.26, respectively). Cost was significantly lower for children receiving clindamycin monotherapy and highest in those receiving clindamycin plus MRSA coverage (mean, $4,839 vs $5,348, respectively; P <.001).

CONCLUSIONS

In children with SSSS, the addition of MSSA or MRSA coverage to clindamycin monotherapy was associated with increased cost and no incremental difference in clinical outcomes.

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.

Staphylococcus aureus Skin and Soft Tissue Infection Recurrence Rates in Outpatients: A Retrospective Database Study at 3 US Medical Centers

Background

Staphylococcusaureus skin and soft tissue infections (SA-SSTIs) are common in healthcare and community settings, and recurrences occur at variable frequency, even after successful initial treatment. Knowing the exact burden and timing of recurrent disease is critical to planning and evaluating interventions to prevent recurrent SSTIs.

Methods

In this retrospective study, SSTI cases in patients aged ≥18 years at 3 US medical centers (Columbia, Chicago, Vanderbilt) between 2006 and 2016 were analyzed according to a biennial cohort design. Index SSTIs (with or without key comorbidities), either microbiologically confirmed to be SA-SSTI or not microbiologically tested (NMT-SSTI), were recorded within 1 calendar year and followed up for 12 months for recurrent infections. The number of index cases, proportion of index cases with ≥1 recurrence(s), time to first recurrence, and number of recurrences were collected for both SA-SSTI and NMT-SSTI events.

Results

In the most recent cohorts, 4755 SSTI cases were reported at Columbia, 2873 at Chicago, and 6433 at Vanderbilt. Of these, 452, 153, and 354 cases were confirmed to be due to S. aureus. Most cases were reported in patients without key comorbidities. Across centers, 16.4%–19.0% (SA-SSTI) and 11.0%–19.2% (NMT-SSTI) of index cases had ≥1 recurrence(s). In patients without key comorbidities, more than 60% of index SSTIs with recurrences had only 1 recurrence, half of which occurred in the first 3 months following primary infection.

Conclusions

SA-SSTI recurrences are common among healthy adults and occur in at least 1 in 6 individuals during the 1 year following the primary event.

Clinical feasibility study of an immunotropic drug for treatment of complicated pyodermas

Introduction: Given a wide range of pathogenesis of the inflammatory process in pyoderma, which involves a variety of links in the immune response, work is underway to find ways to optimize immunocorrection in this pathology. The aim of the study was to evaluate the clinical and economic effectiveness of immunocorrection in severe and chronic forms of pyoderma with drugs from different pharmacological groups.

Materials and methods: The data sources were prospective randomized comparative studies of therapy of 107 pyoderma patients aged 18 to 60 years, divided into groups. The patients of the first group additionally used a biologically active additive containing immunoactive molecules and transfer factors (TF) as an immunomodulator; the patients of the second group used glucosaminylmuramildipeptide (GMDP). The clinical effectiveness of regression of inflammatory symptoms on day 10 of treatment was analyzed. Based on the obtained data, the following types of pharmacoeconomical analysis were performed: calculation of the course price, the cost/effectiveness ratio, and the availability coefficient.

Results and discussion: The results of the study showed that the number of cured patients was 91.4% in the first group and 97.2% in the second group of patients. The treatment cost when using the drug is by 970 rubles smaller; the cost/effectiveness ratio (CER) per patient was 1.8 higher for a drug containing transfer factors and amounted to 25.9. The calculation of the availability coefficient (AC) revealed a difference in glucosaminylmuramyldipeptide which was 2.1 times smaller.

Conclusion: It was found that a drug based on glucosaminylmuramildipeptide is a more effective and cost-effective means of immunocorrection in severe forms of pyoderma. This confirms a faster regression of clinical manifestations of the disease and lower cost/effectiveness ratio and availability coefficient.

Methicillin-Resistant Staphylococcus aureus Eradication and Decolonization in Children Study (Part 2): Patient- and Parent-Centered Outcomes of Decolonization

BACKGROUND

Skin and soft tissue infections (SSTIs) due to community-acquired methicillin-resistant Staphylococcus aureus (MRSA) can lead to a number of significant known medical outcomes including hospitalization, surgical procedures such as incision and drainage (I&D), and the need for decolonization procedures to remove the bacteria from the skin and nose and prevent recurrent infection. Little research has been done to understand patient and caregiver-centered outcomes associated with the successful treatment of MRSA infection.

OBJECTIVE

This study aimed to uncover MRSA decolonization outcomes that are important to patients and their parents in order to create a set of prototype measures for use in the MRSA Eradication and Decolonization in Children (MEDiC) study.

METHODS

A 4-hour, human-centered design (HCD) workshop was held with 5 adolescents (aged 10-18 years) who had experienced an I&D procedure and 11 parents of children who had experienced an I&D procedure. The workshop explored the patient and family experience with skin infection to uncover patient-centered outcomes of MRSA treatment. The research team analyzed the audio and artifacts created during the workshop and coded for thematic similarity. The final themes represent patient-centered outcome domains to be measured in the MEDiC comparative effectiveness trial.

RESULTS

The workshop identified 9 outcomes of importance to patients and their parents: fewer MRSA outbreaks, improved emotional health, improved self-perception, decreased social stigma, increased amount of free time, increased control over free time, fewer days of school or work missed, decreased physical pain and discomfort, and decreased financial burden.

CONCLUSIONS

This study represents an innovative HCD approach to engaging patients and families with lived experience with MRSA SSTIs in the study design and trial development to determine meaningful patient-centered outcomes. We were able to identify 9 major recurrent themes. These themes were used to develop the primary and secondary outcome measures for MEDiC, a prospectively enrolling comparative effectiveness trial.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02127658; https://clinicaltrials.gov/ct2/show/NCT02127658.

Methicillin-Resistant Staphylococcus aureus Eradication and Decolonization in Children Study (Part 1): Development of a Decolonization Toolkit With Patient and Parent Advisors

BACKGROUND

Community-acquired methicillin-resistant Staphylococcus aureus (MRSA) skin and soft tissue infections affect many healthy children. A significant number of these children are hospitalized and require surgical incision and drainage (I&D). Once sent home, these children and families are asked to complete burdensome home decolonization and hygiene procedures in an effort to prevent the high rate of recurrent infections.

OBJECTIVE

This component of the Methicillin-resistant Staphylococcus aureus Eradication and Decolonization in Children (MEDiC) study aimed to develop a toolkit to assist MEDiC study participants in completing MRSA decolonization and hygiene procedures at home (the MEDiC kit).

METHODS

In all, 5 adolescents (aged 10-18 years) who had undergone an I&D procedure for a skin infection and 11 parents of children who had undergone an I&D procedure for a skin infection were engaged in a 4-hour group workshop using a human-centered design approach. The topics covered in this workshop and analyzed for this paper were (1) attitudes about MRSA decolonization procedures and (2) barriers to the implementation of MRSA decolonization and hygiene procedures. The team analyzed the audio and artifacts created during the workshop and synthesized their findings to inform the creation of the MEDiC kit.

RESULTS

The workshop activities uncovered barriers to successful completion of the decolonization and hygiene procedures: lack of step-by-step instruction, lack of proper tools in the home, concerns about adverse events, lack of control over some aspects of the hygiene procedures, and general difficulty coordinating all the procedures. Many of these could be addressed as part of the MEDiC kit. In addition, the workshop revealed that effective communication about decolonization would have to address concerns about the effects of bleach, provide detailed information, give reasons for the specific decolonization and hygiene protocol steps, and include step-by-step instructions (preferably through video).

CONCLUSIONS

Through direct engagement with patients and families, we were able to better understand how to support families in implementing MRSA decolonization and hygiene protocols. In addition, we were able to better understand how to communicate about MRSA decolonization and hygiene protocols. With this knowledge, we created a robust toolkit that uses patient-driven language and visuals to help support patients and families through the implementation of these protocols.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02127658; https://clinicaltrials.gov/ct2/show/NCT02127658.

Impact of Decolonization Protocols and Recurrence in Pediatric MRSA Skin and Soft-Tissue Infections

BACKGROUND

Methicillin-resistant staphylococcus aureus (MRSA) colonization is associated with the development of skin and soft-tissue infection in children. Although MRSA decolonization protocols are effective in eradicating MRSA colonization, they have not been shown to prevent recurrent MRSA infections. This study analyzed the prescription of decolonization protocols, rates of MRSA abscess recurrence, and factors associated with recurrence.

MATERIALS AND METHODS

This study is a single-institution retrospective review of patients ≤18 y of age diagnosed with MRSA culture-positive abscesses who underwent incision and drainage (I&D) at a tertiary-care children's hospital. The prescription of an MRSA decolonization protocol was recorded. The primary outcome was MRSA abscess recurrence.

RESULTS

Three hundred ninety-nine patients with MRSA culture-positive abscesses who underwent I&D were identified. Patients with previous history of abscesses, previous MRSA infection groin/genital region abscesses, higher number of family members with a history of abscess/cellulitis or MRSA infection, and I&D by a pediatric surgeon were more likely to be prescribed decolonization. Decolonized patients did not have lower rates of recurrence. Recurrence was more likely to occur in patients with previous abscesses, previous MRSA infection, family history of abscesses, family history of MRSA infection, Hispanic ethnicity, and those with fever on admission.

CONCLUSIONS

MRSA decolonization did not decrease the rate of recurrence of MRSA abscesses in our patient cohort. Patients at high risk for MRSA recurrence such as personal or family history of abscess or MRSA infection, Hispanic ethnicity, or fever on admission did not benefit from decolonization.

Increasing Clindamycin and Trimethoprim-Sulfamethoxazole Resistance in Pediatric Staphylococcus aureus Infections

The epidemiology of Staphylococcus aureus infection in children is dynamic. We conducted a retrospective observational study on pediatric clinical cultures, performed between 2005 and 2017, that grew S aureus to determine temporal trends in antibiotic resistance. Although methicillin resistance declined, clindamycin and trimethoprim-sulfamethoxazole resistance increased significantly, especially among community-onset isolates.

Prevention Strategies for Recurrent Community-Associated Staphylococcus aureus Skin and Soft Tissue Infections

PURPOSE OF REVIEW

Staphylococcus aureus skin and soft tissue infections (SSTI) are a major source of morbidity. More than half of patients experiencing SSTI will have at least one recurrent infection. These infections frequently cluster in households. Given the burden these infections pose to patients and healthcare, prevention strategies are of major clinical importance and represent an active area of research. Bacterial colonization is frequently an early and critical step in the pathogenesis of infection. As such, strategies to prevent reinfection have aimed to decrease staphylococcal colonization of the skin and mucus membranes, a process referred to as decolonization.

RECENT FINDINGS

Treatment of acute SSTI with incision and drainage and systemic antibiotics is the mainstay of therapy for healing of the acute infection. Systemic antibiotics also provide benefit through reduced incidence of recurrent SSTI. Education for patients and families regarding optimization of personal and household hygiene measures, and avoidance of sharing personal hygiene items, is an essential component in prevention efforts. For patients experiencing recurrent SSTI, or in households in which multiple members have experienced SSTI, decolonization should be recommended for all household members. A recommended decolonization regimen includes application of intranasal mupirocin and antiseptic body washes with chlorhexidine or dilute bleach water baths. For patients who continue to experience recurrent SSTI, periodic decolonization should be considered. Personal decolonization with topical antimicrobials and antiseptics reduces the incidence of recurrent S. aureus SSTI. Future avenues for investigation include strategies for household environmental decontamination as well as manipulation of the host microbiota.

Common Community-acquired Bacterial Skin and Soft-tissue Infections in Children: an Intersociety Consensus on Impetigo, Abscess, and Cellulitis Treatment

PURPOSE

The main objective of this article was to offer practical suggestions, given the existing evidence, for identifying and managing bacterial impetigo, abscess, and cellulitis in ambulatory and hospital settings.

METHODS

Five Italian pediatric societies appointed a core working group. In selected conditions, specially trained personnel evaluated quality assessment of treatment strategies according to the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. Only randomized controlled trials (RCTs) and observational studies were included for quality assessment according to the GRADE methodology. MEDLINE, Ovid MEDLINE, EMBASE, and Cochrane Library databases were searched with a strategy combining MeSH and free text terms.

FINDINGS

The literature review included 364 articles focusing on impetigo, skin abscess, and cellulitis/orbital cellulitis. The articles included for quality assessment according to the GRADE methodology for impetigo comprised 5 RCTs and 1 observational study; for skin abscess, 10 RCTs and 3 observational studies were included; for cellulitis and erysipelas, 5 RCTs and 5 observational studies were included; and for orbital cellulitis, 8 observational studies were included. Recommendations were formulated according to 4 grades of strength for each specific topic (impetigo, skin abscesses, cellulitis, and orbital cellulitis). Where controversies arose and expert opinion was considered fundamental due to lack of evidence, agreement according to Delphi consensus recommendations was included.

IMPLICATIONS

Based on a literature review and on local epidemiology, this article offers practical suggestions for use in both ambulatory and hospital settings for managing the most common bacterial SSTIs.

Variation in Antibiotic Selection and Clinical Outcomes in Infants <60 Days Hospitalized With Skin and Soft Tissue Infections

OBJECTIVES

To describe variation in empirical antibiotic selection in infants <60 days old who are hospitalized with skin and soft-tissue infections (SSTIs) and to determine associations with outcomes, including length of stay (LOS), 30-day returns (emergency department revisit or readmission), and standardized cost.

METHODS

Using the Pediatric Health Information System, we conducted a retrospective study of infants hospitalized with SSTI from 2009 to 2014. We analyzed empirical antibiotic selection in the first 2 days of hospitalization and categorized antibiotics as those typically administered for (1) staphylococcal infection, (2) neonatal sepsis, or (3) combination therapy (staphylococcal infection and neonatal sepsis). We examined the association of antibiotic selection and outcomes using generalized linear mixed-effects models.

RESULTS

A total of 1319 infants across 36 hospitals were included; the median age was 30 days (interquartile range [IQR]: 17-42 days). We observed substantial variation in empirical antibiotic choice, with 134 unique combinations observed before categorization. The most frequently used antibiotics included staphylococcal therapy (50.0% [IQR: 39.2-58.1]) and combination therapy (45.4% [IQR: 36.0-56.0]). Returns occurred in 9.2% of infants. Compared with administration of staphylococcal antibiotics, use of combination therapy was associated with increased LOS (adjusted rate ratio: 1.35; 95% confidence interval: 1.17-1.53) and cost (adjusted rate ratio: 1.39; 95% confidence interval: 1.21-1.58), but not with 30-day returns.

CONCLUSIONS

Infants who are hospitalized with SSTI experience wide variation in empirical antibiotic selection. Combination therapy was associated with increased LOS and cost, with no difference in returns. Our findings reveal the need to identify treatment strategies that can be used to optimize resource use for infants with SSTI.

Antibiotics for uncomplicated skin abscesses: systematic review and network meta-analysis

OBJECTIVE

To assess the impact of adjunctive antibiotic therapy on uncomplicated skin abscesses.

DESIGN

Systematic review and network meta-analysis.

DATA SOURCES

Medline, Embase, the Cochrane Central Register of Controlled Trials and ClinicalTrials.gov.

STUDY SELECTION

A BMJ Rapid Recommendation panel provided input on design, important outcomes and the interpretation of the results. Eligible randomised controlled trials (RCTs) included a comparison of antibiotics against no antibiotics or a comparison of different antibiotics in patients with uncomplicated skin abscesses, and reported outcomes prespecified by the linked guideline panel.

REVIEW METHODS

Reviewers independently screened abstracts and full texts for eligibility, assessed risk of bias and extracted data. We performed random-effects meta-analyses that compared antibiotics with no antibiotics, along with a limited number of prespecified subgroup hypotheses. We also performed network meta-analysis with a Bayesian framework to compare effects of different antibiotics. Quality of evidence was assessed with The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

RESULTS

Fourteen RCTs including 4198 patients proved eligible. Compared with no antibiotics, antibiotics probably lower the risk of treatment failure (OR 0.58, 95% CI 0.37 to 0.90; low quality), recurrence within 1 month (OR 0.48, 95% CI 0.30 to 0.77; moderate quality), hospitalisation (OR 0.55, 95% CI 0.32 to 0.94; moderate quality) and late recurrence (OR 0.64, 95% CI 0.48 to 0.85; moderate quality). However, relative to no use, antibiotics probably increase the risk of gastrointestinal side effects (trimethoprim and sulfamethoxazole (TMP-SMX): OR 1.28, 95% CI 1.04 to 1.58; moderate quality; clindamycin: OR 2.29, 95% CI 1.35 to 3.88; high quality) and diarrhoea (clindamycin: OR 2.71, 95% CI 1.50 to 4.89; high quality). Cephalosporins did not reduce the risk of treatment failure compared with placebo (moderate quality).

CONCLUSIONS

In patients with uncomplicated skin abscesses, moderate-to-high quality evidence suggests TMP-SMX or clindamycin confer a modest benefit for several important outcomes, but this is offset by a similar risk of adverse effects. Clindamycin has a substantially higher risk of diarrhoea than TMP-SMX. Cephalosporins are probably not effective.

Impact of Systemic Antibiotics on Staphylococcus aureus Colonization and Recurrent Skin Infection

Background

Staphylococcus aureus colonization poses risk for subsequent skin and soft tissue infection (SSTI). We hypothesized that including systemic antibiotics in the management of S. aureus SSTI, in conjunction with incision and drainage, would reduce S. aureus colonization and incidence of recurrent infection.

Methods

We prospectively evaluated 383 children with S. aureus SSTI requiring incision and drainage and S. aureus colonization in the anterior nares, axillae, or inguinal folds at baseline screening. Systemic antibiotic prescribing at the point of care was recorded. Repeat colonization sampling was performed within 3 months (median, 38 days; interquartile range, 22-50 days) in 357 participants. Incidence of recurrent infection was ascertained for up to 1 year.

Results

Participants prescribed guideline-recommended empiric antibiotics for purulent SSTI were less likely to remain colonized at follow-up sampling (adjusted hazard ratio [aHR], 0.49; 95% confidence interval [CI], .30-.79) and less likely to have recurrent SSTI (aHR, 0.57; 95% CI, .34-.94) than those not receiving guideline-recommended empiric antibiotics for their SSTI. Additionally, participants remaining colonized at repeat sampling were more likely to report a recurrent infection over 12 months (aHR, 2.37; 95% CI, 1.69-3.31). Clindamycin was more effective than trimethoprim-sulfamethoxazole (TMP-SMX) in eradicating S. aureus colonization (44% vs 57% remained colonized, P = .03) and preventing recurrent SSTI (31% vs 47% experienced recurrence, P = .008).

Conclusions

Systemic antibiotics, as part of acute SSTI management, impact S. aureus colonization, contributing to a decreased incidence of recurrent SSTI. The mechanism by which clindamycin differentially affects colonization and recurrent SSTI compared to TMP-SMX warrants further study.

Sulfamethoxazole-Trimethoprim (Cotrimoxazole) for Skin and Soft Tissue Infections Including Impetigo, Cellulitis, and Abscess

Skin and soft tissue infections (SSTI) affect millions of people globally, which represents a significant burden on ambulatory care and hospital settings. The role of sulfamethoxazole-trimethoprim (SXT) in SSTI treatment, particularly when group A Streptococcus (GAS) is involved, is controversial. We conducted a systematic review of clinical trials and observational studies that address the utility of SXT for SSTI treatment, caused by either GAS or Staphylococcus aureus, including methicillin-resistant (MRSA). We identified 196 studies, and 15 underwent full text review by 2 reviewers. Observational studies, which mainly focused on SSTI due to S aureus, supported the use of SXT when compared with clindamycin or β-lactams. Of 10 randomized controlled trials, 8 demonstrated the efficacy of SXT for SSTI treatment including conditions involving GAS. These findings support SXT use for treatment of impetigo and purulent cellulitis (without an additional β-lactam agent) and abscess and wound infection. For nonpurulent cellulitis, β-lactams remain the treatment of choice.

The rise of methicillin resistant Staphylococcus aureus: now the dominant cause of skin and soft tissue infection in Central Australia

This study aimed to examine the epidemiology and treatment outcomes of community-onset purulent staphylococcal skin and soft tissue infections (SSTI) in Central Australia. We performed a prospective observational study of patients hospitalised with community-onset purulent staphylococcal SSTI (n = 160). Indigenous patients accounted for 78% of cases. Patients were predominantly young adults; however, there were high rates of co-morbid disease. Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) was the dominant phenotype, accounting for 60% of cases. Hospitalisation during the preceding 6 months, and haemodialysis dependence were significant predictors of CA-MRSA infection on univariate analysis. Clinical presentation and treatment outcomes were found to be comparable for methicillin-susceptible S. aureus (MSSA) and methicillin-resistant cases. All MRSA isolates were characterised as non-multi-resistant, with this term used interchangeably with CA-MRSA in this analysis. We did not find an association between receipt of an active antimicrobial agent within the first 48 h, and progression of infection; need for further surgical debridement; unplanned General Practitioner or hospital re-presentation; or need for further antibiotics. At least one adverse outcome was experienced by 39% of patients. Clindamycin resistance was common, while rates of trimethoprim-sulfamethoxazole resistance were low. This study suggested the possibility of healthcare-associated transmission of CA-MRSA. This is the first Australian report of CA-MRSA superseding MSSA as the cause of community onset staphylococcal SSTI.

Diffusion of clindamycin-resistant and erythromycin-resistant methicillin-susceptible Staphylococcus aureus (MSSA), potential ST398, in United States Veterans Health Administration Hospitals, 2003-2014

Background

Changing phenotypic profiles of methicillin-susceptible Staphylococcus aureus (MSSA) isolates can indicate the emergence of novel sequence types (ST). The diffusion of MSSA ST can be tracked by combining established genotypic profiles with phenotypic surveillance data. ST398 emerged in New York City (NYC) and exhibits resistance to clindamycin and erythromycin but tetracycline susceptibility (“potential ST398”). Trends of potential ST398 were examined in a national cohort of all Veterans Health Administration patients with MSSA invasive infections during 2003–2014.

Methods

A retrospective cohort of all patients with MSSA invasive infections, defined as a positive clinical culture from a sterile site, during 2003–2014 was created. Only isolates tested against clindamycin, erythromycin and tetracycline were included. Annual hospital-level proportions of potential ST398 were compared according to facility distance from NYC and region.

Results

A total of 34,025 patient isolates from 136 VA medical centers met the inclusion criteria. Of those, 4582 (13.5%) met the definition of potential ST398. Potential ST398 increased over the 12-year cohort and diffused outwards from NYC. Incidence Rate Ratios of >1.0 (p < 0.01) reflect increases in potential ST398 over time in hospitals nearer to NYC.

Conclusions

We observe an increase in the phenotypic profile of potential ST398 MSSA isolates in invasive infections in a national cohort of patients in the US. The increase is not evenly distributed across the US but appears to diffuse outwards from NYC. Novel MSSA strain emergence may have important clinical implications, particularly for the use of clindamycin for suspected S. aureus infections.

Staphylococcus aureus in the Intensive Care Unit: Are These Golden Grapes Ripe for a New Approach?

Staphylococcus aureus is the leading cause of infection in the setting of critical illness and injury. This pathogen causes life-threatening infection in otherwise healthy individuals and also complicates the clinical course of patients requiring intensive care as a result of their primary medical or surgical disease processes. S. aureus infection in the intensive care unit (ICU) most commonly manifests as sepsis, ventilator-associated pneumonia, and infection of surgical sites and indwelling medical devices. With the epidemic spread of methicillin-resistant S. aureus, many cases of staphylococcal infection in the ICU are now classified as drug resistant, prompting hospital-based screening for methicillin-resistant S. aureus and implementation of both isolation practices and decolonization strategies in ICU patients. The genetic adaptability of S. aureus, heterogeneity of disease presentation, clinical course, and outcome between individual S. aureus-infected ICU patients remains enigmatic, suggesting a need to define disease classification subtypes that inform disease progression and therapy. We propose that S. aureus infection in the ICU now presents a unique opportunity for individualized risk stratification coupled with the investigation of novel approaches to mitigate disease. Given our increasing knowledge of the molecular pathogenesis of S. aureus disease, we suggest that the application of molecular pathological epidemiology to S. aureus infection can usher in a new era of highly focused personalized therapy that may be particularly beneficial in the setting of critical illness and injury.

A Randomized Trial of Clindamycin Versus Trimethoprim-sulfamethoxazole for Uncomplicated Wound Infection

BACKGROUND

With the emergence of community-associated methicillin-resistant Staphylococcus aureus (MRSA) in the United States, visits for skin infections greatly increased. Staphylococci and streptococci are considered predominant causes of wound infections. Clindamycin and trimethoprim-sulfamethoxazole (TMP-SMX) are commonly prescribed, but the efficacy of TMP-SMX has been questioned.

METHODS

We conducted a randomized, double-blind, superiority trial at 5 US emergency departments. Patients >12 years of age with an uncomplicated wound infection received oral clindamycin 300 mg 4 times daily or TMP-SMX 320 mg/1600 mg twice daily, each for 7 days. We compared the primary outcome, wound infection cure at 7-14 days, and secondary outcomes through 6-8 weeks after treatment, in the per-protocol population.

RESULTS

Subjects had a median age of 40 years (range, 14-76 years); 40.1% of wound specimens grew MRSA, 25.7% methicillin-susceptible S. aureus, and 5.0% streptococci. The wound infection was cured at 7-14 days in 187 of 203 (92.1%) clindamycin-treated and 182 of 198 (91.9%) TMP-SMX-treated subjects (difference, 0.2%; 95% confidence interval [CI], -5.8% to 6.2%; P = not significant). The clindamycin group had a significantly lower rate of recurrence at 7-14 days (1.5% vs 6.6%; difference, -5.1%; 95% CI, -9.4% to -.8%) and through 6-8 weeks following treatment (2.0% vs 7.1%; difference, -5.1%; 95% CI, -9.7% to -.6%). Other secondary outcomes were statistically similar between groups but tended to favor clindamycin. Adverse event rates were similar.

CONCLUSIONS

In settings where MRSA is prevalent, clindamycin and TMP-SMX produce similar cure and adverse event rates among patients with an uncomplicated wound infection. Further study evaluating differential effects of antibiotics on recurrent infection may be warranted.

CLINICAL TRIALS REGISTRATION

NCT00729937.

Prevention of Recurrent Staphylococcal Skin Infections

Staphylococcus aureus infections pose a significant health burden. The emergence of community-associated methicillin-resistant S aureus has resulted in an epidemic of skin and soft tissue infections (SSTI), and many patients experience recurrent SSTI. As S aureus colonization is associated with subsequent infection, decolonization is recommended for patients with recurrent SSTI or in settings of ongoing transmission. S aureus infections often cluster within households, and asymptomatic carriers serve as reservoirs for transmission; therefore, a household approach to decolonization is more effective than measures performed by individuals alone. Novel strategies for the prevention of recurrent SSTI are needed.

Optimizing antimicrobial therapy in children

Management of common infections and optimal use of antimicrobial agents are presented, highlighting new evidence from the medical literature that enlightens practice. Primary therapy of staphylococcal skin abscesses is drainage. Patients who have a large abscess (>5 cm), cellulitis or mixed abscess-cellulitis likely would benefit from additional antibiotic therapy. When choosing an antibiotic for outpatient management, the patient, pathogen and in vitro drug susceptibility as well as tolerability, bioavailability and safety characteristics of antibiotics should be considered. Management of recurrent staphylococcal skin and soft tissue infections is vexing. Focus is best placed on reducing density of the organism on the patient's skin and in the environment, and optimizing a healthy skin barrier. With attention to adherence and optimal dosing, acute uncomplicated osteomyelitis can be managed with early transition from parenteral to oral therapy and with a 3-4 week total course of therapy. Doxycycline should be prescribed when indicated for a child of any age. Its use is not associated with dental staining. Azithromycin should be prescribed for infants when indicated, whilst being alert to an associated ≥2-fold excess risk of pyloric stenosis with use under 6 weeks of age. Beyond the neonatal period, acyclovir is more safely dosed by body surface area (not to exceed 500 mg/m(2)/dose) than by weight. In addition to the concern of antimicrobial resistance, unnecessary use of antibiotics should be avoided because of potential later metabolic effects, thought to be due to perturbation of the host's microbiome.

Is Trimethoprim-Sulfamethoxazole a Valid Alternative in the Management of Infections in Children in the Era of Community-Acquired Methicillin-Resistant Staphylococcus aureus? A Comprehensive Systematic Review

Objective. To evaluate the use of TMP-SMX compared with other options available for the treatment of children with community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) infections. Data Sources. The following databases were searched: Medline and PreMedline (OivdSP interface); Excerpta Medica Database (EMBASE; Elsevier interface); Cumulative Index to the Nursing and Allied Health Literature (CINAHL; EbscoHost interface); Sciences Citation Index Expanded (SCI-EXPANDED; Web of Science interface); Cochrane Library (Wiley interface); Scopus (Elsevier interface), and DARE, HTA (CRD interface). The search strategy was the one developed by SIGN to identify randomized clinical trials and systematic reviews. Also, we conducted a hand review of all reference lists of included studies. No language or data limits were added. The last search was done on October 1, 2015. Main key words were trimethoprim or trimethoprim-sulfamethoxazole combination and Staphylococcus aureus. Study Selection. Only randomized controlled trials comparing TMP-SMX versus any other antibiotic as the first-line treatment in CA-MRSA infections in children were included. Articles were reviewed by 2 reviewers, and in case of discrepancy, the final decision was made by the study coordinator. Data Extraction. Only 27 out of 364 articles identified were randomized controlled trials and only 4 fulfilled the eligibility criteria (Jadad score >3). Data Synthesis. Evidence found only referred to use of TMP-SMX in soft tissue infections. Heterogeneity among studies precluded meta-analysis. Conclusions. Available evidence is not conclusive to promote or refuse TMP-SMX as first-line treatment in CA-MRSA infections in children. Additional well-designed studies are required to fsurther elucidate this issue.

Decreasing Duration of Antibiotic Prescribing for Uncomplicated Skin and Soft Tissue Infections

BACKGROUND AND OBJECTIVE

Short courses of antibiotics are often indicated for uncomplicated skin and soft tissue infections (uSSTIs). Our objective was to decrease duration of antibiotics prescribed in children hospitalized for uSSTIs by using quality improvement (QI) methods.

METHODS

QI methods were used to decrease duration of antibiotics prescribed upon hospital discharge for uSSTIs. We sought to accomplish this goal by increasing outpatient prescriptions for short courses of therapy (≤7 days). Key drivers included awareness of evidence among physicians, changing the culture of prescribing, buy-in from prescribers, and monitoring of prescribing. Physician education, modification of antibiotic order sets for discharge prescriptions, and continual identification and mitigation of therapy plans, were key interventions implemented by using plan-do-study-act cycles. A run chart assessed the impact of the interventions over time.

RESULTS

We identified 641 index admissions for uSSTIs over a 23-month period for patients aged >90 days to 18 years. The proportion of children discharged with short courses of antibiotics increased from a baseline median of 23% to 74%, which was sustained for 6 months. Differences in the proportion of children admitted for treatment failure or recurrence before and after project initiation were not significant.

CONCLUSIONS

Using QI methodology, we decreased duration of antibiotics prescribed in children hospitalized for uSSTIs by increasing prescriptions for short courses of antibiotics. Modification of electronic order sets for discharge prescriptions allowed for sustained improvement in prescribing practices. Our findings support the use of shorter outpatient antibiotic courses in most children with uSSTIs, and suggest criteria for complicated SSTIs.

Staphylococcus aureus-Associated Skin and Soft Tissue Infections: Anatomical Localization, Epidemiology, Therapy and Potential Prophylaxis

Skin and soft tissue infections (SSTIs) are among the most common infections worldwide. They range in severity from minor, self-limiting, superficial infections to life-threatening diseases requiring all the resources of modern medicine. Community (CA) and healthcare (HA) acquired SSTIs are most commonly caused by Staphylococcus aureus . They have variable presentations ranging from impetigo and folliculitis to surgical site infections (SSIs). Superficial SSTIs may lead to even more invasive infections such as bacteraemia and osteomyelitis. Here we describe the anatomical localization of the different SSTI associated with S. aureus, the virulence factors known to play a role in these infections, and their current epidemiology. Current prevention and treatment strategies are also discussed. Global epidemiological data show increasing incidence and severity of SSTIs in association with methicillin-resistant S. aureus strains (MRSA). CA-SSTIs are usually less morbid compared to other invasive infections caused by S. aureus, but they have become the most prevalent, requiring a great number of medical interventions, extensive antibiotic use, and therefore a high cost burden. Recurrence of SSTIs is common after initial successful treatment, and decolonization strategies have not been effective in reducing recurrence. Furthermore, decolonization approaches may be contributing to the selection and maintenance of multi-drug resistant strains. Clinical studies from the early 1900s and novel autovaccination approaches suggest an alternative strategy with potential effectiveness: using vaccines to control S. aureus cutaneous infections.

Vaccines for Staphylococcus aureus and Target Populations

Staphylococcus aureus is a leading pathogen in surgical site, intensive care unit, and skin infections, as well as healthcare-associated pneumonias. These infections are associated with an enormous burden of morbidity, mortality, and increase of hospital length of stay and patient cost. S. aureus is impressively fast in acquiring antibiotic resistance, and multidrug-resistant strains are a serious threat to human health. Due to resistance or insufficient effectiveness, antibiotics and bundle measures leave a tremendous unmet medical need worldwide. There are no licensed vaccines on the market despite the significant efforts done by public and private initiatives. Indeed, vaccines tested in clinical trials in the last two decades have failed to show efficacy. However, they targeted single antigens and contained no adjuvants and efficacy trials were performed in severely ill subjects. Herein, we provide a comprehensive evaluation of potential target populations for efficacy trials taking into account key factors such as population size, incidence of S. aureus infection, disease outcome, primary endpoints, as well as practical advantages and disadvantages. We describe the whole-blood assay as a potential surrogate of protection, and we show the link between phase III clinical trial data of failed vaccines with their preclinical observations. Finally, we give our perspective on how new vaccine formulations and clinical development approaches may lead to successful S. aureus vaccines.

Outcomes After Skin and Soft Tissue Infection in Infants 90 Days Old or Younger

BACKGROUND AND OBJECTIVES

Skin and soft tissue infections (SSTIs) are an increasingly common cause of pediatric hospital visits among infants. The optimal evaluation strategy for younger infants with SSTI is unknown because there is little information about outcomes including risks of concomitant bacterial infections and treatment failure. This study was designed to determine rates of concomitant invasive bacterial infection and hospital revisits for treatment failure as well as factors associated with treatment failure in infants presenting with SSTI.

METHODS

Retrospective study of patients≤90 days of age who received care from the 22 emergency departments and hospitals in the Intermountain Healthcare system from July 1, 2004 to December 31, 2011, with a primary discharge diagnosis of SSTI. Concomitant bacterial infections were defined as urinary tract infection (UTI; culture-confirmed) or invasive bacterial infection (IBI; culture-confirmed bacteremia and/or meningitis). Treatment failure was defined as any unplanned change in care at hospital revisit within 14 days of discharge.

RESULTS

The study included 172 infants; 29 (17%) were febrile, and 91 (53%) had ≥1 sterile site culture performed. One case of bacteremia in a febrile infant was identified giving an overall proportion with UTI/IBI of 0.58% (95% confidence interval 0.01%-3.2%). Sixteen infants (9.3%; 95% confidence interval 5.4%-14.7%) returned for treatment failure. Perianal location (P=.03) and private insurance status (P=.01) were associated with more treatment failures compared with other locations or payer types. No patients returned for missed UTI/IBI.

CONCLUSIONS

Concomitant bacterial infections were rare in infants with SSTI, with none identified in afebrile infants. Treatment failure of SSTI leading to hospital revisit was common.

Second Annual Meeting of the International Society of Pediatric Wound Care

The overarching goals of the International Society of Pediatric Wound Care (ISPeW) are to (1) set global standards for the assessment and treatment of pediatric wounds of varying etiologies; (2) provide a forum for international interprofessional collaboration among healthcare professionals, researchers, educators, and industry leaders dedicated to the care of pediatric wounds; (3) promote and support clinical research focused on the prevention, assessment, and treatment of pediatric wounds; (4) collaborate with wound care organizations worldwide on pediatric wound care issues; and (5) provide evidence-based pediatric wound care education to healthcare professionals, parents, and lay caregivers. This edition of Advances in Wound Care includes some of the work that was presented at the 2014 ISPeW meeting in Rome. The first article by Dr. Romanelli, is an in-depth description of the progression of skin physiology throughout its maturational stages and clinical implication. A cutting edge article by Dr. Timothy King then follows, with regard to scar prevention in postnatal tissues. This is followed by a comprehensive look at debridement techniques in pediatric trauma by Dr. Ankush Gosain. Next, is a cautionary article by Dr. Luca Spazzapan that examines the prevalence of diabetic foot ulcers in children and the potential for an epidemic. The last article in this series is from the keynote speaker, Dr. Amit Geffen, who eloquently examines the use of biomaterials to offload and prevent pediatric pressure ulcers.

Database Research for Pediatric Infectious Diseases

Multiple electronic and administrative databases are available for the study of pediatric infectious diseases. In this review, we identify research questions well suited to investigations using these databases and highlight their advantages, including their relatively low cost, efficiency, and ability to detect rare outcomes. We discuss important limitations, including those inherent in observational study designs and the potential for misclassification of exposures and outcomes, and identify strategies for addressing these limitations. We provide examples of commonly used databases and discuss methodologic considerations in undertaking studies using large databases. Last, we propose a checklist for use in planning or evaluating studies of pediatric infectious diseases that employ electronic databases, and we outline additional practical considerations regarding the cost of and how to access commonly used databases.

Decolonization of children after incision and drainage for MRSA abscess: a retrospective cohort study

BACKGROUND/PURPOSE

Whether decolonization following incision and drainage (I&D) for methicillin-resistant Staphylococcus aureus (MRSA) abscess decreases repeat I&D and MRSA-positive cultures in children is unknown.

MATERIALS/METHODS

Referral to the Pediatric Infectious Disease Service (PIDS) for decolonization was determined for eligible children (2003-2010), with outcomes studied over 12 months.

RESULTS

We identified 653 children; 54 had been seen by PIDS. In the PIDS group, no patients (0/54, 0%) had a repeat I&D. In the no PIDS group 36/599 (6%) had a repeat I&D, P = .06. Logistic regression modeling for repeat I&D showed no significant effect, odds ratio = 0.29; 95% confidence interval = 0.04-2.15; P = .23. In the PIDS group, 3 patients (3/54, 5.6%) had a repeat MRSA-positive culture. In the no PIDS group, 58/599 (9.7%) had a positive repeat culture, P = .46. Logistic regression modeling for positive culture showed no significant effect (odds ratio = 0.55; 95% confidence interval = 0.17-1.81; P = .32).

CONCLUSIONS

We detected no statistically significant association between decolonization and repeat I&D or MRSA-positive culture.

Failure of Emergency Department Observation Unit Treatment for Skin and Soft Tissue Infections

BACKGROUND

The effectiveness of observation unit (OU) management of skin and soft tissue infections (SSTI) has not been fully evaluated.

OBJECTIVE

This study was performed to determine the rate and risk factors.

METHODS

Retrospective cohort study of children ages 2 months to 18 years admitted to the OU for an SSTI between 2007 and 2010 from a pediatric emergency department (ED). Failure of OU therapy was defined as subsequent inpatient ward admission, re-admission after discharge from OU, initial or repeat incision and drainage after OU admission, or change in antibiotic therapy. Demographic, clinical, and lesion characteristics were collected. Comparative analyses were conducted to determine factors associated with OU failure; prolonged OU admission, defined as length of stay ≥ 36 h was evaluated.

RESULTS

One hundred ninety-two (63.2%) of 304 subjects with SSTI were eligible; mean age was 6.2 ± 5.3 years, and 52% were male. Fever (≥38°C) in the ED was present for 77 (40%). Most lesions were skin abscesses (53%) and were located on the lower extremity (36%) and buttock/genitourinary (21%). OU treatment failure occurred in 22% (95% confidence interval [CI] 16.5-28.3), primarily due to inpatient admission. Fever on ED presentation was significantly associated with OU failure (odds ratio 2.02; 95% CI 1.02-4.02). Demographics, body site, presence of abscess, and methicillin-resistant Staphylococcus aureus were not associated with OU failure. Prolonged OU admission occurred in 18 subjects (9.4%).

CONCLUSION

SSTI can be successfully treated in the OU, though febrile children with SSTI are at risk for OU treatment failure and should be considered for inpatient admission.

Clindamycin versus trimethoprim-sulfamethoxazole for uncomplicated skin infections

BACKGROUND

Skin and skin-structure infections are common in ambulatory settings. However, the efficacy of various antibiotic regimens in the era of community-acquired methicillin-resistant Staphylococcus aureus (MRSA) is unclear.

METHODS

We enrolled outpatients with uncomplicated skin infections who had cellulitis, abscesses larger than 5 cm in diameter (smaller for younger children), or both. Patients were enrolled at four study sites. All abscesses underwent incision and drainage. Patients were randomly assigned in a 1:1 ratio to receive either clindamycin or trimethoprim-sulfamethoxazole (TMP-SMX) for 10 days. Patients and investigators were unaware of the treatment assignments and microbiologic test results. The primary outcome was clinical cure 7 to 10 days after the end of treatment.

RESULTS

A total of 524 patients were enrolled (264 in the clindamycin group and 260 in the TMP-SMX group), including 155 children (29.6%). One hundred sixty patients (30.5%) had an abscess, 280 (53.4%) had cellulitis, and 82 (15.6%) had mixed infection, defined as at least one abscess lesion and one cellulitis lesion. S. aureus was isolated from the lesions of 217 patients (41.4%); the isolates in 167 (77.0%) of these patients were MRSA. The proportion of patients cured was similar in the two treatment groups in the intention-to-treat population (80.3% in the clindamycin group and 77.7% in the TMP-SMX group; difference, -2.6 percentage points; 95% confidence interval [CI], -10.2 to 4.9; P=0.52) and in the populations of patients who could be evaluated (466 patients; 89.5% in the clindamycin group and 88.2% in the TMP-SMX group; difference, -1.2 percentage points; 95% CI, -7.6 to 5.1; P=0.77). Cure rates did not differ significantly between the two treatments in the subgroups of children, adults, and patients with abscess versus cellulitis. The proportion of patients with adverse events was similar in the two groups.

CONCLUSIONS

We found no significant difference between clindamycin and TMP-SMX, with respect to either efficacy or side-effect profile, for the treatment of uncomplicated skin infections, including both cellulitis and abscesses. (Funded by the National Institute of Allergy and Infectious Diseases and the National Center for Advancing Translational Sciences, National Institutes of Health; ClinicalTrials.gov number, NCT00730028.).

Invasive Staphylococcus aureus Infections in Children in Tropical Northern Australia

BACKGROUND

Despite a high burden of staphylococcal skin disease in children and high incidence of Staphylococcus aureus bacteremia in adult Indigenous populations in northern Australia, there are few studies describing incidence or clinical information of invasive S aureus (ISA) infections in children.

METHODS

We conducted a retrospective review for all cases of S aureus bacteremia and sterile site infections, for children under 15 years, in northern Australia over a 4-year period (2007-2010). Cases were categorized as neonatal (<28 days) and pediatric (≥28 days).

RESULTS

Forty-four cases (9 neonatal, 35 pediatric) were identified. The annual incidence of ISA was 27.9 cases per 100 000 population. Among pediatric cases, the annual incidence was significantly higher in the Indigenous (46.6) compared with the non-Indigenous (4.4) population (IRR: 10.6 [95% confidence interval, 3.8-41.4]). Pediatric infections were predominantly community-associated (86%). Clinical infection sites included osteoarticular (66%), pleuropulmonary (29%), and endocarditis (9%), and multifocal disease was common (20%). Eighty-three percent of pediatric cases presented with sepsis; 34% resulted in intensive care admission. Neonatal cases were all born prematurely; 89% were late-onset infections. Overall, 27% of infections were due to methicillin-resistant S aureus (MRSA). Compared with methicillin-sensitive S aureus (MSSA), there was no difference in severity or presentation in pediatric MRSA cases, but a higher proportion of MRSA cases were readmitted.

CONCLUSIONS

The annual incidence of ISA infection in this study is among the highest described, largely due to a disproportionate burden in Indigenous children. Infections are frequently severe and infection with MRSA is common. Children presenting with suspected ISA in this region should be treated empirically for MRSA.

Quality improvement and comparative effectiveness: a review for the pediatric hospitalist

Quality improvement (QI) and comparative effectiveness research (CER) are increasingly important areas of study for the pediatric hospitalist. The focus of this article is to provide the relevant background, definitions, framework, infrastructure, and resources needed to both inform and engage the pediatric hospital medicine (PHM) community on QI and CER. In mastering these activities, PHM physicians will have a key role in shaping the health care transformation expected over the next decade and beyond.

Staphylococcus aureus - antimicrobial resistance and the immunocompromised child

Children with immunocompromising conditions represent a unique group for the acquisition of antimicrobial resistant infections due to their frequent encounters with the health care system, need for empiric antimicrobials, and immune dysfunction. These infections are further complicated in that there is a relative paucity of literature on the clinical features and management of Staphylococcus aureus infections in immunocompromised children. The available literature on the clinical features, antimicrobial susceptibility, and management of S. aureus infections in immunocompromised children is reviewed. S. aureus infections in children with human immunodeficiency virus (HIV) are associated with higher HIV viral loads and a greater degree of CD4 T-cell suppression. In addition, staphylococcal infections in children with HIV often exhibit a multidrug resistant phenotype. Children with cancer have a high rate of S. aureus bacteremia and associated complications. Increased tolerance to antiseptics among staphylococcal isolates from pediatric oncology patients is an emerging area of research. The incidence of S. aureus infections among pediatric solid organ transplant recipients varies considerably by the organ transplanted; in general however, staphylococci figure prominently among infections in the early posttransplant period. Staphylococcal infections are also prominent pathogens among children with a number of immunodeficiencies, notably chronic granulomatous disease. Significant gaps in knowledge exist regarding the epidemiology and management of S. aureus infection in these vulnerable children.

Cutaneous bacterial infections caused by Staphylococcus aureus and Streptococcus pyogenes in infants and children

Acute bacterial skin and skin structure infections (SSSIs) are among the most common bacterial infections in children. The medical burden of SSSIs, particularly abscesses, has increased nationwide since the emergence of community-acquired methicillin-resistant Staphylococcus aureus. SSSIs represent a wide spectrum of disease severity. Prompt recognition, timely institution of appropriate therapy, and judicious antimicrobial use optimize patient outcomes. For abscesses, incision and drainage are paramount and might avoid the need for antibiotic treatment in uncomplicated cases. If indicated, empiric antimicrobial therapy should target Streptococcus pyogenes for nonpurulent SSSIs, such as uncomplicated cellulitis, and S aureus for purulent SSSIs such as abscesses.

Pediatric fecal microbiota harbor diverse and novel antibiotic resistance genes

Emerging antibiotic resistance threatens human health. Gut microbes are an epidemiologically important reservoir of resistance genes (resistome), yet prior studies indicate that the true diversity of gut-associated resistomes has been underestimated. To deeply characterize the pediatric gut-associated resistome, we created metagenomic recombinant libraries in an Escherichia coli host using fecal DNA from 22 healthy infants and children (most without recent antibiotic exposure), and performed functional selections for resistance to 18 antibiotics from eight drug classes. Resistance-conferring DNA fragments were sequenced (Illumina HiSeq 2000), and reads assembled and annotated with the PARFuMS computational pipeline. Resistance to 14 of the 18 antibiotics was found in stools of infants and children. Recovered genes included chloramphenicol acetyltransferases, drug-resistant dihydrofolate reductases, rRNA methyltransferases, transcriptional regulators, multidrug efflux pumps, and every major class of beta-lactamase, aminoglycoside-modifying enzyme, and tetracycline resistance protein. Many resistance-conferring sequences were mobilizable; some had low identity to any known organism, emphasizing cryptic organisms as potentially important resistance reservoirs. We functionally confirmed three novel resistance genes, including a 16S rRNA methylase conferring aminoglycoside resistance, and two tetracycline-resistance proteins nearly identical to a bifidobacterial MFS transporter (B. longum s. longum JDM301). We provide the first report to our knowledge of resistance to folate-synthesis inhibitors conferred by a predicted Nudix hydrolase (part of the folate synthesis pathway). This functional metagenomic survey of gut-associated resistomes, the largest of its kind to date, demonstrates that fecal resistomes of healthy children are far more diverse than previously suspected, that clinically relevant resistance genes are present even without recent selective antibiotic pressure in the human host, and that cryptic gut microbes are an important resistance reservoir. The observed transferability of gut-associated resistance genes to a gram-negative (E. coli) host also suggests that the potential for gut-associated resistomes to threaten human health by mediating antibiotic resistance in pathogens warrants further investigation.

Skin and soft tissue infections

The approach to common skin and soft tissue infections (SSTIs) was previously well understood. However, the recent emergence of community-associated methicillin resistant Staphyloccocus aureus as a common pathogen has changed the epidemiology of these infections and has led clinicians to alter their practice and treatment of SSTI. This article discusses the present epidemiology of SSTI and community-acquired methicillin-resistant Staphylococcus aureus, evidence-based approach to incision and drainage, the utility of adjuvant antibiotic therapy after abscess drainage, and current antimicrobial approach to cellulitis and nondrained SSTIs. Methods to reduce transmission and recurrence of SSTI through decolonization strategies are also discussed.

Update on Epidemiology and Treatment of MRSA Infections in Children

In 2000-10 the epidemiology of pediatric MRSA infections in the United States was transformed with an epidemic of CA-MRSA infections. We review the epidemiology of MRSA in the community and in the health care setting, including intensive care units, among infants and CF patients, and in households as well as the impact that the CA-MRSA epidemic has had on hospitalization with MRSA infections. Risk factors for carriage, transmission, and initial and recurrent infection with MRSA are discussed. New studies on the treatment of pediatric MRSA infections and on the efficacy of MRSA decolonization are reviewed.

Use of electronic health record data to identify skin and soft tissue infections in primary care settings: a validation study

Background

Epidemiologic studies of skin and soft tissue infections (SSTIs) depend upon accurate case identification. Our objective was to evaluate the positive predictive value (PPV) of electronic medical record data for identification of SSTIs in a primary care setting.

Methods

A validation study was conducted among primary care outpatients in an academic healthcare system. Encounters during four non-consecutive months in 2010 were included if any of the following were present in the electronic health record: International Classification of Diseases, Ninth Revision (ICD-9) code for an SSTI, Current Procedural Terminology (CPT) code for incision and drainage, or a positive wound culture. Detailed chart review was performed to establish presence and type of SSTI. PPVs and 95% confidence intervals (CI) were calculated among all encounters, initial encounters, and cellulitis/abscess cases.

Results

Of the 731 encounters included, 514 (70.3%) were initial encounters and 448 (61.3%) were cellulitis/abscess cases. When the presence of an ICD-9 code, CPT code, or positive culture was used to identify SSTIs, 617 encounters were true positives, yielding a PPV of 84.4% [95% CI: 81.8–87.0%]. The PPV for using ICD-9 codes alone to identify SSTIs was 90.7% [95 % CI: 88.5–92.9%]. For encounters with cellulitis/abscess codes, the PPV was 91.5% [95% CI: 88.9–94.1%].

Conclusions

ICD-9 codes may be used to retrospectively identify SSTIs with a high PPV. Broadening SSTI case identification with microbiology data and CPT codes attenuates the PPV. Further work is needed to estimate the sensitivity of this method.

National surveillance of methicillin-resistant Staphylococcus aureus among hospitalized pediatric patients in Canadian acute care facilities, 1995-2007

BACKGROUND

Information relating to the epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) among hospitalized pediatric patients is limited. This report describes results of national MRSA surveillance among Canadian hospitalized pediatric patients from 1995 to 2007.

METHODS

Surveillance was laboratory-based. Clinical and epidemiologic data were obtained by reviewing the medical records. Standardized definitions were used to determine MRSA infection. Isolates were characterized by pulsed-field gel electrophoresis, staphylococcal cassette chromosome mec typing and antimicrobial susceptibility testing.

RESULTS

A total of 1262 pediatric patients were newly identified as MRSA positive from 1995 to 2007. Ages ranged from newborn to 17.9 years, 49% were infected with MRSA (51% colonized), skin and soft tissue infections accounted for the majority (59%) of MRSA infections and 57% were epidemiologically classified as community acquired (CA). The most common epidemic strain types isolated were CMRSA2/USA100/800, CMRSA10/USA300 and CMRSA7/USA400. Overall, MRSA rates per 10,000 patient days increased from 0.08 to 3.88. Since 2005, overall rates of CA-MRSA per 10,000 patient days have dramatically increased while healthcare-associated MRSA rates remained relatively stable.

CONCLUSIONS

These data suggest that the increase in MRSA among hospitalized pediatric patients is largely driven by the emergence of CA-MRSA strains with skin and soft tissue infections representing the majority of MRSA infections.