Pediatric Musculoskeletal Infections Research Articles

391. Septic Arthritis and Acute Hematogenous Osteomyelitis in Children: Disease-Specific Antibiogram and Implications for Treatment

BackgroundOsteomyelitis and septic arthritis are common pediatric musculoskeletal infections with potential to cause significant morbidity. Empiric antibiotic selection is made prior to the availability of microbiologic data. The aim of this study was to compare the epidemiology of osteoarticular infections (OAI) to antibiotic regimens and local antibiograms.MethodsA retrospective study was performed on patients aged 6 months to 18 years with a diagnosis of septic arthritis or acute hematogenous osteomyelitis in a large, free-standing children’s hospital between July 2012 and July 2017. Exclusion criteria were chronic osteomyelitis, prior trauma or surgery at the site, noninfectious arthritis, and Lyme arthritis. Data collected from the electronic medical record included demographics, initial and discharge antibiotic therapy, and microbiologic results. Data were compared with the local antibiogram during the same time period.ResultsA total of 207 patients were included: 66 patients <4 years (< 4Y) and 141 patients ≥4 years (≥4Y). Causative pathogens were identified in 70% of patients. Staphylococcus aureus comprised 55% of positive results in children < 4Y and 73% in children ≥4Y. Among S. aureus cultures, 70–76% were methicillin sensitive (MSSA). Overall clindamycin susceptibility was 97%, with all resistant strains detected in children ≥4Y with MSSA. This is strikingly different than the institutional antibiogram showing 79% overall clindamycin sensitivity in S. aureus [82% in MSSA, 72% in methicillin resistant (MRSA)]. Kingella kingae was exclusively identified in children <4Y (21% of positives), which was also the group with the highest rate of culture-negative infection (41%). Intravenous clindamycin alone was the most frequent initial antibiotic regimen, prescribed for 41% of all patients. Initial antibiotic regimens matched organism susceptibilities in 90% of MRSA and 100% of MSSA infections.ConclusionOur study revealed high rates of clindamycin-susceptible S. aureus in older children and K. kingae and culture-negative infection in children < 4 years with OAI. Antibiotic susceptibilities differing from our institutional antibiogram suggest that disease-specific antibiograms will aid with empiric treatment decisions.Disclosures All authors: No reported disclosures.

Musculoskeletal Infection in Pediatrics: Assessment of the 2018 International Consensus Meeting on Musculoskeletal Infection.

The Second International Consensus Meeting (ICM) on Musculoskeletal Infection was held in July 2018 in Philadelphia, Pennsylvania. This meeting involved contributions from an international multidisciplinary consortium of experts from orthopaedic surgery, infectious disease, pharmacology, rheumatology, microbiology, and others. Through strict delegate engagement in a comprehensive 13-step consensus process based on the Delphi technique, evidence-based consensus guidelines on musculoskeletal infection were developed. The 2018 ICM produced updates to recommendations from the inaugural ICM that was held in 2013, which primarily focused on periprosthetic infection of the hip and the knee, and added new guidelines with the expansion to encompass all subspecialties of orthopaedic surgery. The following proceedings from the pediatrics section are an overview of the ICM consensus recommendations on the prevention, diagnosis, and treatment of pediatric musculoskeletal infection.

Potential Clinical Effects of a Novel Rapid Diagnostic Panel for Pediatric Musculoskeletal Infections.

A direct-from-source rapid musculoskeletal diagnostic panel (MDP) was validated recently. We compared clinical measures to theoretical time points had MDP results been available. The MDP would have significantly decreased the time to pathogen identification (7 hours), time to definitive antimicrobial therapy (22 hours), and hospital length of stay (26.4 hours).

A Clinical Prediction Algorithm to Stratify Pediatric Musculoskeletal Infection by Severity.

There are currently no algorithms for early stratification of pediatric musculoskeletal infection (MSKI) severity that are applicable to all types of tissue involvement. In this study, the authors sought to develop a clinical prediction algorithm that accurately stratifies infection severity based on clinical and laboratory data at presentation to the emergency department. An IRB-approved retrospective review was conducted to identify patients aged 0 to 18 who presented to the pediatric emergency department at a tertiary care children's hospital with concern for acute MSKI over a 5-year period (2008 to 2013). Qualifying records were reviewed to obtain clinical and laboratory data and to classify in-hospital outcomes using a 3-tiered severity stratification system. Ordinal regression was used to estimate risk for each outcome. Candidate predictors included age, temperature, respiratory rate, heart rate, C-reactive protein (CRP), and peripheral white blood cell count. We fit fully specified (all predictors) and reduced models (retaining predictors with a P-value ≤0.2). Discriminatory power of the models was assessed using the concordance (c)-index. Of the 273 identified children, 191 (70%) met inclusion criteria. Median age was 5.8 years. Outcomes included 47 (25%) children with inflammation only, 41 (21%) with local infection, and 103 (54%) with disseminated infection. Both the full and reduced models accurately demonstrated excellent performance (full model c-index 0.83; 95% confidence interval, 0.79-0.88; reduced model 0.83; 95% confidence interval, 0.78-0.87). Model fit was also similar, indicating preference for the reduced model. Variables in this model included CRP, pulse, temperature, and an interaction term for pulse and temperature. The odds of a more severe outcome increased by 30% for every 10 U increase in CRP. Clinical and laboratory data obtained in the emergency department may be used to accurately differentiate pediatric MSKI severity. The predictive algorithm in this study stratifies pediatric MSKI severity at presentation irrespective of tissue involvement and anatomic diagnosis. Prospective studies are needed to validate model performance and clinical utility. Level II-prognostic study.

Can a Septic Hip Decision Rule Aid in the Evaluation of Suspected Pediatric Musculoskeletal Infections?

Musculoskeletal (MSK) infections can be difficult to diagnose in acute care settings. The utility of clinical decision tools for pediatric MSK infections in an emergency department has not been well studied. Our aim was to evaluate the performance of a septic hip clinical decision rule (CDR) in the evaluation of pediatric musculoskeletal infections. We performed a retrospective study of children evaluated for an MSK infection in our emergency department from 2014 to 2016. Data collection included demographics, discharge diagnoses, and clinical/laboratory predictors from the CDR. A χ2 analysis and Wilcoxon rank-sum tests compared patients with and without MSK infections. Logistic regression analysis examined the predictors for MSK infections. A receiver operating characteristic (ROC) curve was calculated to evaluate the performance of the predictors. Of 996 evaluations included in the final analysis, 109 (10.9%) had MSK infections. In a multivariable model, an adjusted odds ratio (OR) was significant for fever (OR 3.9, 95% confidence interval [CI] 2.4-6.4), refusal to bear weight/pseudoparalysis (OR 4.4, 95% CI 2.7-7.1), and C-reactive protein (CRP)>2.0mg/dL (OR 5.4, 95% CI 3.2-9.1). The probability of infection was 75.1% with five predictors present, 1.9% for zero predictors, and 5.1% if one predictor was present. An ROC curve showed an area under the curve of 0.82, indicating moderate accuracy. A septic hip CDRdemonstrates a low predicted probability of an MSK infection with zero or one clinical predictor present andmoderate predictability with all five predictors. Fever, refusal to bear weight/pseudoparalysis, and CRP > 2.0mg/dL performed best and should alert providers to considerother MSK infections in addition to septic arthritis.

C-Reactive Protein Predicts Risk of Venous Thromboembolism in Pediatric Musculoskeletal Infection.

The rate of venous thromboembolism in children with musculoskeletal infections (MSKIs) is markedly elevated compared with hospitalized children in general. Predictive biomarkers to identify high-risk patients are needed to prevent the significant morbidity and rare mortality associated with thrombotic complications. We hypothesize that overactivation of the acute phase response is associated with the development of pathologic thrombi and we aim to determine whether elevations in C-reactive protein (CRP) are associated with increased rates of thrombosis in pediatric patients with MSKI. A retrospective cohort study measuring CRP in pediatric MSKI patients with or without thrombotic complications. The magnitude and duration of elevation in CRP values correlated with the severity of infection and the development of pathologic thrombosis. In multivariable logistic regression, every 20 mg/L increase in peak CRP was associated with a 29% increased risk of thrombosis (P<0.001). Peak and total CRP were strong predictors of thrombosis with area under the receiver-operator curves of 0.90 and 0.92, respectively. Future prospective studies are warranted to further define the discriminatory power of CRP in predicting infection-provoked thrombosis. Pharmacologic prophylaxis and increased surveillance should be strongly considered in patients with MSKI, particularly those with disseminated disease and marked elevation of CRP. Level III.

Validation of a novel molecular diagnostic panel for pediatric musculoskeletal infections: Integration of the Cepheid Xpert MRSA/SA SSTI and laboratory-developed real-time PCR assays for clindamycin resistance genes and Kingella kingae detection

BackgroundPathogen detection in pediatric patients with musculoskeletal infections relies on conventional bacterial culture, which is slow and can delay antimicrobial optimization. The ability to rapidly identify causative agents and antimicrobial resistance genes in these infections may improve clinical care. MethodsConvenience specimens from bone and joint samples submitted for culture to Children's Hospital Colorado (CHCO) from June 2012 to October 2016 were evaluated using a “Musculoskeletal Diagnostic Panel” (MDP) consisting of the Xpert MRSA/SA SSTI real-time PCR (qPCR, Cepheid) and laboratory-developed qPCRs for Kingella kingae detection and erm genes A, B, and C which confer clindamycin resistance. Results from the MDP were compared to culture and antimicrobial susceptibility testing (AST) results. ResultsA total of 184 source specimens from 125 patients were tested. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the Xpert MRSA/SA SSTI compared to culture and AST results were 85%, 98%, 93%, and 95% respectively for MSSA and 82%, 100%, 100%, and 99% for MRSA. Compared to phenotypic clindamycin resistance in S. aureus isolates, the erm A, B, and C gene PCRs collectively demonstrated a sensitivity, specificity, PPV, and NPV of 80%, 96%, 67%, and 98%. In comparison to clinical truth, Kingella PCR had a sensitivity, specificity, PPV, and NPV of 100%, 99.5%, 100%, and 100%. ConclusionsThis novel MDP offers a rapid, sensitive, and specific option for pathogen detection in pediatric patients with musculoskeletal infections.

Performance of TEM-PCR vs Culture for Bacterial Identification in Pediatric Musculoskeletal Infections.

Improved diagnostics are needed for children with musculoskeletal infections (MSKIs). We assessed the performance of target-enriched multiplex polymerase chain reaction (TEM-PCR) in children with MSKI. TEM-PCR was concordant with culture in pathogen identification and antibiotic susceptibility testing, while increasing the overall yield of pathogen detection. This technology has the potential to inform judicious antimicrobial use early in the disease course.

Does Pre-Culture Antibiotic Administration Lead to Non-Diagnostic Bone and Joint Culture Results in Pediatric Osteomyelitis and Septic Arthritis: A 12-Year Retrospective Review

1) Purpose: Pediatric musculoskeletal infections can be devastating, with ramifications that can cause lasting morbidity. Children often receive antibiotics in various clinical settings prior to having cultures obtained. A commonly held notion is that administration of antibiotics prior to obtaining samples from the involved musculoskeletal site will result in negative cultures. The purpose of our study was to evaluate whether …

The Epidemiology and Regional Burden of Musculoskeletal Infection In Pediatric Orthopaedics

Purpose Pediatric musculoskeletal infection (MSKI) is a significant cause of morbidity, mortality and hospital resource utilization. Effective clinical practice guidelines are necessary to guide care and maximize the use of hospital resources. However, it is hypothesized that the burden and cause of MSKI varies widely with geography, thus may require region-specific guidelines to optimize the quality, safety, and value of care for children with MSKI. The purpose of this study was to determine the epidemiology and regional differences in burden and causative microbes in MSKI evaluated and treated by pediatric orthopaedic surgeons. Methods Seventeen CORTICES centers (Figure-1A) retrospectively reviewed a minimum of 1 year of patient charts from 2010–2016 (average 2.6 years) reporting the annual number of emergency department (ED) visits, orthopaedic consultations, MSKI-related consultations, patients with …

Clinical Care Guideline for Improving Pediatric Acute Musculoskeletal Infection Outcomes.

Acute pediatric musculoskeletal infections are common, leading to significant use of resources and antimicrobial exposure. In order to decrease variability and improve the quality of care, Children's Hospital Colorado implemented a clinical care guideline (CCG) for these infections. The purpose of this study is to evaluate clinical and resource outcomes PRE and POST this CCG. Retrospective chart review evaluated patients admitted to a large pediatric quaternary referral center (CHCO) diagnosed with acute osteomyelitis, septic arthritis, pyomyositis, and/or musculoskeletal abscess prior to and after guideline implementation. Primary outcomes included length of stay and overall antibiotic use, with additional secondary clinical, process, and therapeutic outcomes examined. 82 patients were identified in both the pre-CCG and post-CCG cohorts. There was a reduction in the median of all primary outcomes, including length of stay (0.6 median days decrease, P = .04), length of IV antibiotic therapy (4.9 median days decrease, P < .0001), and days of IV antibiotic therapy (6.4 median days decrease, P = .0004). Our median length of stay post-CCG was 4.9 days, the shortest reported length of stay for pediatric acute musculoskeletal infections to date. Additionally, there was a 24.5 hour reduction in median length of fever (P = .02), faster CRP normalization (P < .0001), 50% decrease in the number of related readmissions (P = .02), 34% decrease in central venous catheters placed (P < .0001), decreased time to first culture (P = .02), and 79% pathogen identification post-CCG (P = .056). Implementation of a CCG for acute musculoskeletal infections improves patient, process and resource outcomes.

Experience With a Care Process Model in the Evaluation of Pediatric Musculoskeletal Infections in a Pediatric Emergency Department.

Care process models (CPMs) for certain conditions have improved clinical outcomes in children. This study describes the implementation and impact of a CPM for the evaluation of musculoskeletal infections in a pediatric emergency department (ED). A retrospective pre-post intervention study was performed to analyze the impact of a musculoskeletal infection CPM. Patients were identified retrospectively through electronic order history for imaging of an extremity or joint and recommended laboratory tests. Clinical outcomes evaluated included hospital length of stay (LOS), time to magnetic resonance imaging (MRI), time to administration of antibiotics, hospital admission rate, and 30-day readmission rate. Musculoskeletal infection evaluations completed in the ED were reviewed from 1 year before implementation (n = 383) and 2 years after implementation (n = 1219) of the CPM. A significant improvement in the time to antibiotic administration for all patients (4.3 vs 3.7 hours, P < 0.05) and for patients with confirmed musculoskeletal infections (9.5 vs 4.9 hours, P < 0.05) was observed after the implementation of the CPM. The overall time to MRI (13.2 vs 10.3 hours, P = 0.29) and hospital LOS (4.7 vs 3.7 days, P = 0.11) were improved for all patients but were not statistically significant. The admission rate and 30-day readmission were similar before and after the implementation of the CPM. The implementation of a musculoskeletal infection CPM has standardized the approach to the evaluation and diagnosis of musculoskeletal infections resulting in a significant decrease in the time to administer antibiotics and a downward trend in time to MRI and hospital LOS.

Performance of TEM-PCR vs. Culture for Bacterial Identification in Pediatric Musculoskeletal Infections

BackgroundMusculoskeletal infections (MSI) in children require prompt diagnosis and treatment due to risk of local tissue damage and metastatic bacterial spread. Staphylococcus aureus is the leading cause of MSI and readily grows in culture; however, receipt of antibiotics prior to culture and the frequency of fastidious organisms in young children (e.g., Kingella kingae) often leads to negative cultures and broad treatment regimens. Thus, there is a need for improved rapid diagnostics in children with MSI. In this study, we compared the detection of MSI pathogens by culture and by target-enriched multiplex PCR (TEM-PCR™) in children with MSI.MethodsSynovial fluid and bone samples were collected from patients with MSI (n = 25, 0.5–18 years). Bacterial cultures and antibiotic susceptibility testing (AST) was performed by the Vanderbilt University Medical Center clinical laboratory. Additionally, samples were evaluated by TEM-PCR for detection of S. aureus [including methicillin and clindamycin resistance genes and the Panton–Valentine leukocidin (PVL) locus], K. kingae, Haemophilus influenzae, Streptococcus pyogenes, and Streptococcus pneumoniae.ResultsTEM-PCR detected a pathogen in 20/25 subjects (80%), compared with 17/25 (68%) by culture. S. aureus was identified in 18 subjects, one of which was identified by TEM-PCR and not by culture. TEM-PCR also identified 2 subjects with K. kingae infection; neither was identified by culture. TEM-PCR detection of methicillin resistance and clindamycin resistance was 100% concordant with AST in the clinical laboratory. Genes encoding PVL were identified in 8/18 (44%) S. aureus samples. No bacterial co-detections were identified, and no other pathogens were identified by TEM-PCR or culture. Finally, there were no subjects with positive bacterial cultures and negative TEM-PCR results.ConclusionRapid diagnostic assays, such as TEM-PCR, may be useful adjuncts to conventional, culture-based testing for children with MSI. Advantages include rapid identification of pathogen and early detection of antibiotic resistance genes. In a single multiplex assay, TEM-PCR provided reliable identification of MSI pathogens, with the potential for informing antibiotic selection early in the disease course.Disclosures J. Wood Jr., Diatherix: Investigator, Research support; C. Sesler, Diatherix Laboratories, LLC: Employee, Salary; D. Stalons, Diatherix Laboratories: Employee, Salary; E. Grigorenko, Diatherix Laboratories: Employee, Salary; C. B. Creech, Diatherix: Grant Investigator, Grant recipient; I. Thomsen, Diatherix: Investigator, Research support

Similar Clinical Severity and Outcomes for Methicillin-Resistant and Methicillin-Susceptible Staphylococcus aureus Pediatric Musculoskeletal Infections.

BackgroundPrior studies of pediatric musculoskeletal infection have suggested that methicillin-resistant Staphylococcus aureus (MRSA) infections result in worse outcomes compared with infections with methicillin-susceptible S aureus (MSSA) strains. Based on these results, clinical prediction algorithms have been developed to differentiate between MRSA and MSSA early in a patient’s clinical course. This study compares hospital outcomes for pediatric patients with MRSA and MSSA musculoskeletal infection presenting to the emergency department at a large tertiary care children’s hospital.MethodsA retrospective study identified pediatric patients with S aureus musculoskeletal infection over a 5-year period (2008–2013) by sequential review of all pediatric orthopedic consults. Relevant demographic information, laboratory values, and clinical outcomes were obtained from the electronic medical record.ResultsOf the 91 identified cases of S aureus pediatric musculoskeletal infection, there were 49 cases of MRSA infection (53%) and 42 cases of MSSA infection (47%). There were no significant differences between MRSA and MSSA infections in median hospital length of stay (4.8 vs 5.7 days, P = .50), febrile days (0.0 vs 1.5 days, P = .10), and antibiotic duration (28 vs 34 days, P = .18). Methicillin-resistant S aureus infections were more likely to require operative intervention than MSSA infection (85% vs 62%, P = .15). A logistic regression model based on C-reactive protein, temperature, white blood cell count, pulse, and respiratory rate at presentation demonstrated poor ability to differentiate between MRSA and MSSA infection.ConclusionsThe results demonstrated no significant differences between MSSA and MRSA musculoskeletal infections for most hospital outcomes measured. However, MRSA infections required more operative interventions than MSSA infections. In addition, a predictive model based on severity markers obtained at presentation was unable to effectively differentiate between MRSA and MSSA infection. The clinical utility and capacity for early differentiation of MRSA and MSSA depends on virulence patterns that may vary temporally and geographically.

Effects of Antibiotic Timing on Culture Results and Clinical Outcomes in Pediatric Musculoskeletal Infection.

Musculoskeletal infection (MSI) is a common cause of morbidity and hospital resource utilization in the pediatric population. Many physicians prefer to withhold antibiotics until tissue cultures can be taken in an effort to improve culture yields. However, there is little evidence that this practice improves culture results or outcomes in pediatric MSI. Therefore, investigating the effects of antibiotic timing may lead to improved clinical practice guidelines for treating children with MSI. An IRB-approved retrospective review was conducted that identified 113 patients aged 0 to 18 who presented to the pediatric emergency room at a tertiary care children's hospital with MSI from 2008 to 2013. Demographic data, culture results, severity markers, and intervention timing were obtained from the medical record. Logistic regression and Cox survival analysis were performed to determine the relationship of antibiotic timing with culture sensitivity and time to discharge. No difference was seen in culture sensitivity antibiotic administration in either the local (55% culture before antibiotics vs. 89% after antibiotics) or disseminated group (76% before vs. 79% after), which persisted when further accounting for disease severity with C-reactive protein. However, later administration of antibiotics in the local infection group correlated with a decreased likelihood of discharge (3.91 d when cultured before antibiotics vs. 2.93 d when cultured after antibiotics; hazard ratio, 0.53; P<0.05). In patients with disseminated infection, antibiotic administration was not shown to correlate with any difference in time to discharge (hazard ratio, 1.08). The authors were surprised to find that tissue culture sensitivities were not decreased by antibiotic administration in either local or disseminated MSI, suggesting that antibiotic administration should not be delayed to obtain tissue cultures. The correlation of earlier antibiotic administration with shorter length of stay in children with local MSI led the authors to conclude that antibiotics should be initiated as quickly as possible. Further study is necessary to confirm these findings and establish clinical practice guidelines. Level III-retrospective cohort.

A Novel Classification System Based on Dissemination of Musculoskeletal Infection is Predictive of Hospital Outcomes.

Musculoskeletal infections (MSKIs) are a common cause of pediatric hospitalization. Children affected by MSKI have highly variable hospital courses, which seem to depend on infection severity. Early stratification of infection severity would therefore help to maximize resource utilization and improve patient care. Currently, MSKIs are classified according to primary diagnoses such as osteomyelitis, pyomyositis, etc. These diagnoses, however, do not often occur in isolation and may differ widely in severity. On the basis of this, the authors propose a severity classification system that differentiates patients based on total infection burden and degree of dissemination. The authors developed a classification system with operational definitions for MSKI severity based on the degree of dissemination. The operational definitions were applied retrospectively to a cohort of 202 pediatric patients with MSKI from a tertiary care children's hospital over a 5-year period (2008 to 2013). Hospital outcomes data [length of stay (LOS), number of surgeries, positive blood cultures, duration of antibiotics, intensive care unit LOS, number of days with fever, and number of imaging studies] were collected from the electronic medical record and compared between groups. Patients with greater infection dissemination were more likely to have worse hospital outcomes for LOS, number of surgeries performed, number of positive blood cultures, duration of antibiotics, intensive care unit LOS, number of days with fever, and number of imaging studies performed. Peak C-reactive protein, erythrocyte sedimentation rate, white blood cell count, and temperature were also higher in patients with more disseminated infection. The severity classification system for pediatric MSKI defined in this study correlates with hospital outcomes and markers of inflammatory response. The advantage of this classification system is that it is applicable to different types of MSKI and represents a potentially complementary system to the previous practice of differentiating MSKI based on primary diagnosis. Early identification of disease severity in children with MSKI has the potential to enhance hospital outcomes through more efficient resource utilization and improved patient care. Level II-prognostic study.

Treating Orthopaedic Infections in Pediatric Patients

Pediatric musculoskeletal infections represent a wide spectrum of diseases and pose a treatment challenge for the orthopaedic surgeon. Prompt and accurate diagnosis and treatment are of utmost importance to prevent long-term sequelae and often require a multidisciplinary approach. Staphylococcus aureus is still reported as the most common causative organism of infection, with an increase in the number of methicillin-resistant S. aureus infections in more recent years. Treatment consists of a combination of surgical debridement and antibiotics. Close follow-up is required, as up to 6% of all infected children still suffer from permanent sequela.

Variety of Pediatric Musculoskeletal Infections Stresses Need for Accurate Diagnosis

Musculoskeletal infections are on the rise, and physicians need to recognize the patterns of variability to accurately diagnose and treat. Including magnetic resonance imaging in the diagnostic workup can help understand the full extent of a patient’s infectious disease. Proposed scoring systems can also help predict severe disease.

Microbiological culture methods for pediatric musculoskeletal infection: a guideline for optimal use.

Culture results affect the diagnosis and treatment of children with musculoskeletal infection. To our knowledge, no previous large-scale study has assessed the relative value of culture methods employed during the evaluation of these conditions. The purpose of this study was to identify an optimal culture strategy for pediatric musculoskeletal infection. Children with musculoskeletal infection were retrospectively studied to assess culture results from the infection site or blood; culture type, including aerobic, anaerobic, fungal, and acid-fast bacteria (AFB); antibiotic exposure history; and clinical history of children with positive culture results. We studied 869 children, including 353 with osteomyelitis, 199 with septic arthritis, forty-two with pyomyositis, and 275 with abscess. The 4537 cultures processed included 1303 aerobic, 903 anaerobic, 340 fungal, 289 AFB, and 1702 blood. Of 3004 specimens sent during initial work-up, positive results occurred in 677 of 1049 aerobic cultures (64.5%), 140 of 763 blood cultures (18.3%), eighteen of 722 anaerobic cultures (2.5%), five of 251 fungal cultures (2.0%), and two of 219 AFB cultures (0.9%). Staphylococcus aureus was the most common pathogen isolated, from 428 (50.7%) of 844 children for whom blood or infection-site culture material was sent (methicillin-resistant S. aureus, 252; and oxacillin-sensitive S. aureus, 176). Cultures were negative in 206 (29.0%) of the 710 children for whom culture material from the site of infection was sent. Children with true-positive anaerobic, fungal, or AFB cultures had a history of immunocompromise, penetrating inoculation, or failed primary treatment. Antibiotic exposure prior to culture-sample acquisition did not interfere with aerobic culture results from the site of infection. Our findings suggest that anaerobic, fungal, and AFB cultures should not be routinely performed during the initial evaluation of children with hematogenous musculoskeletal infection. These cultures should be performed for children with immunocompromise, clinical suspicion of penetrating inoculation, or failed primary treatment.

Recent advances in the evaluation and treatment of pediatric musculoskeletal infection

Recent advances in the evaluation and treatment of pediatric musculoskeletal infection