Childhood osteomyelitis-incidence and differentiation from other acute onset musculoskeletal features in a population-based study

[Arthritis and osteomyelitis in childhood and adolescence-Bacterial and nonbacterial]

Bacterial arthritis and osteomyelitis are usually acute diseases, which in this way differ from the often insidious course of nonbacterial osteomyelitis; however, there is often an overlap both in less acute courses of bacterial illnesses and also in nonbacterial osteitis. The overlapping clinical phenomena can be explained by similar pathophysiological processes. In bacteria-related illnesses the identification of the pathogen and empirical or targeted anti-infectious treatment are prioritized, whereas no triggering agent is known for nonbacterial diseases. The diagnostics are based on the exclusion of differential diagnoses, clinical scores and magnetic resonance imaging (MRI). An activity-adapted anti-inflammatory treatment is indicated.

A case report: Osteomyelitis of the ischiopubic synchondrosis with abscess formation

Osteomyelitis of the ischiopubic synchondrosis is an uncommon condition with high morbidity rates that present with nonspecific symptoms in the pediatric population. In this article, we report a case of a 10-year-old female who presented with right hip pain and fever following a trivial trauma. Laboratory tests revealed leukocytosis and elevated inflammatory markers. Despite negative blood culture and deceptively normal plain radiographs, magnetic resonance imaging demonstrated osteomyelitis of the ischiopubic synchondrosis with intra-osseous and intra-muscular abscess which was managed surgically by incision and drainage. We highlight the clinical importance of familiarity with such uncommon condition and the role of early magnetic resonance imaging in establishing the diagnosis to facilitate prompt surgical intervention.

A Novel Risk Score to Guide the Evaluation of Acute Hematogenous Osteomyelitis in Children

OBJECTIVES

To identify independent predictors of and derive a risk score for acute hematogenous osteomyelitis (AHO) in children.

METHODS

We conducted a retrospective matched case-control study of children >90 days to <18 years of age undergoing evaluation for a suspected musculoskeletal (MSK) infection from 2017 to 2019 at 23 pediatric emergency departments (EDs) affiliated with the Pediatric Emergency Medicine Collaborative Research Committee. Cases were identified by diagnosis codes and confirmed by chart review to meet accepted diagnostic criteria for AHO. Controls included patients who underwent laboratory and imaging tests to evaluate for a suspected MSK infection and received an alternate final diagnosis.

RESULTS

We identified 1135 cases of AHO matched to 2270 controls. Multivariable logistic regression identified 10 clinical and laboratory factors independently associated with AHO. We derived a 4-point risk score for AHO using (1) duration of illness >3 days, (2) history of fever or highest ED temperature ≥38°C, (3) C-reactive protein >2.0 mg/dL, and (4) erythrocyte sedimentation rate >25 mm per hour (area under the curve: 0.892, 95% confidence interval [CI]: 0.881 to 0.901). Choosing to pursue definitive diagnostics for AHO when 3 or more factors are present maximizes diagnostic accuracy at 84% (95% CI: 82% to 85%), whereas children with 0 factors present are highly unlikely to have AHO (sensitivity: 0.99, 95% CI: 0.98 to 1.00).

CONCLUSIONS

We identified 10 predictors for AHO in children undergoing evaluation for a suspected MSK infection in the pediatric ED and derived a novel 4-point risk score to guide clinical decision-making.

Treatment of bone infections in children in low-income countries - A practical guideline based on clinical cases

In low-income countries (LIC), the management of bone infections is a huge challenge. A high number of patients are in the pediatric age group. Children and adolescents exhibit good bone healing potential offering treatment options that mainly rely on the biological response of the infected bone. The purpose of this article is to highlight treatment options for these patients in LIC, which is based on clinical cases that illustrate the principles of the treatment, focusing on bone reaction and healing potential. First, identification of emergency cases is of importance. Sepsis of the patient due to bone infections is a life-threatening disease that requires immediate surgical attention with abscess incision. It should be tailored to the surgeon's experience and local conditions to avoid unwanted complications, such as excessive bleeding, fracture or bone loss. In non-septic patients, uncomplicated cases should be distinguished from complicated cases as the first might often require only abscess incision, particularly in small children, without any other major surgical intervention. Biomechanical stability and bone formation capacity, soft tissue conditions and joint involvement are decisive factors differentiating uncomplicated from complicated cases. Central treatment column is the immobilization of the infected bone with simple methods, such as plaster of Paris, braces or external fixation. This is intended to provide sufficient stability to allow for new bone formation that subsequently downsizes the infection site and that can bridge previously infected non-union sites or bone defects. In most cases, antibiotic treatment is not performed as antibiotics are not available or affordable. Severe soft tissue defects remain a major challenge as microvascular surgical experience is often required for reliable coverage, for which referral to one of the very few specialized centers is recommended. Major bone defects should also be treated in centers with sufficient expertise for bone reconstruction procedures. Regular follow-ups are important to ensure healing and to avoid aggravation of the disease. Encouraging success rates can be achieved by these treatment principles. However, it should not be forgotten that poverty in these countries, including limited access to health care, remains one of the world's most important problems.

Clinical study of drug-loaded calcium sulfate in the treatment of hematogenous osteomyelitis in children

BACKGROUND

At present, good results have been obtained in the treatment of hematogenous osteomyelitis(HO) in children by the use of drug-loaded calcium sulfate, but there are few clinical studies reported. The aim of this study was to investigate the clinical efficacy of radical debridement combined with drug-laden calcium sulphate antibiotics in paediatric haematogenous osteomyelitis.

METHODS

In this study, we retrospectively analyzed the clinical data of 15 cases of pediatric hematogenous osteomyelitis admitted to our hospital in recent years. A total of 15 pediatric patients with HO treated in our hospital from January 2018 to February 2022 were included for evaluation.

RESULTS

All 15 patients were treated with drug-laden calcium sulfate, and the antibiotic of choice was vancomycin in 14 cases and vancomycin combined with gentamicin in 1 case. The follow-up period ranged from 12 to 36 months, with a mean follow-up time of 24.73 months, and all children were treated with drug-laden calcium sulfate with satisfactory clinical outcomes. The results of serological examination showed that the preoperative white blood cell count level, C-reactive protein and erythrocyte sedimentation rate were higher than the postoperative ones, and the differences were statistically significant (P < 0.05).After the operation, referring to the treatment standard of McKee's osteomyelitis, 15 cases were cured without recurrence; According to the Lower Extremities Functional Scale, 12 cases were excellent, 2 cases were good and 1 case was moderate, with an excellent rate of 93.33%. Children with lower limb involvement could walk with full weight bearing, and gait was basically normal.

CONCLUSION

Drug-loaded calcium sulfate is a good therapeutic method for the treatment of hematogenous osteomyelitis in children, with a effect of reducing complications and reducing recurrence.

Risk factors of deep vein thrombosis in children with osteomyelitis

OBJECTIVE

To investigate the risk factors for deep vein thrombosis (DVT) in children with osteomyelitis and provide diagnostic and treatment strategies for the prevention, early detection and treatment of DVT.

STUDY DESIGN

The clinical data of nine children diagnosed with osteomyelitis and DVT between July 2012 and March 2021 were collected at our hospital, including age, sex, clinical manifestations, body temperature, coagulation function and other data, as well as the clinical data of 27 children diagnosed with osteomyelitis without DVT during the same period. Thirty-six children were divided into thrombus and thrombus-free groups. The clinical characteristics and risk factors for DVT in children with osteomyelitis were analysed.

RESULTS

Among the 36 children in this study, nine cases of thrombus formation mainly occurred in the femoral vein, popliteal vein and iliac vein, all near the infection site. The main clinical manifestations were lower extremity pain, swelling and pulmonary embolism in three cases. Among them, intensive care unit (ICU) admission, sepsis, higher D-dimer, higher body temperature during hospitalization, and pathogen culture showed that methicillin-resistant Staphylococcus aureus (MRSA) was associated with DVT. MRSA was the independent risk factor for DVT.

CONCLUSIONS

Admission to ICU, sepsis, higher D-dimer, higher body temperature during hospitalization, and MRSA are risk factors for thrombosis. MRSA is the independent risk factor for DVT. For patients with related risk factors, timely ultrasound examination of the infected site should be considered to achieve early detection and treatment.

Efficacy and Safety of Antibiotic Impregnated Microporous Nanohydroxyapatite Beads for Chronic Osteomyelitis Treatment: A Multicenter, Open-Label, Prospective Cohort Study

Chronic osteomyelitis is still a serious health problem that causes disabling conditions and has an impact on the quality of life. The objective of this study was to determine the clinical efficacy and safety of localized antibiotics delivery via impregnated microporous nanohydroxyapatite (nHA-ATB) beads for chronic osteomyelitis treatment. A total of 62 patients were enrolled in this study. After radical surgical debridement, the bone defect was filled with three types of antibiotics (vancomycin or gentamicin or fosfomycin) impregnated HA beads. The follow-up period was 48 weeks. It was found that the success rate was approximately 98% with a re-infection in only one patient. Quality of life of all patients after treatment improved significantly over time. Systemic exposure to vancomycin and gentamicin after beads implantation was limited and high local antibiotics concentrations were found in wound drainage fluid at 24, 48 and 72 h. Blood biochemistry measurements did not show any nephrotoxic or hepatotoxic effects. 20 adverse events were reported, but 90% of the events were resolved without having to remove the beads and the patients recovered. Satisfactory outcomes were observed in terms of success rate, quality of life and adverse effect. nHA-ATB beads impregnated by vancomycin or gentamicin or fosfomycin could potentially be employed as an alternative product of choice for localized antibiotics delivery in chronic osteomyelitis treatment.

Pediatric musculoskeletal infections

PURPOSE OF REVIEW

The aim of this article is to review the recent guidelines and literature regarding the diagnosis and the treatment of common pediatric musculoskeletal infections: septic arthritis, osteomyelitis, pyomyositis, and Lyme disease.

RECENT FINDINGS

In the last decade, a better understanding of the causative organisms of common bacterial infections, including Kingella , leads to prompt targeted antimicrobial coverage in all musculoskeletal infections. Prompt diagnosis and treatment continues to be the mainstay in the treatment of children with osteoarticular infections. Efforts to improve early detection have lead to improving rapid lab diagnostic testing; however, more advanced diagnostics such as arthrocentesis for septic arthritis and MRI for osteomyelitis and pyomyositis, remain the gold standard. Shorter and narrowed antibiotic courses, with appropriate transition to outpatient oral treatment provide effective infection clearance and reduction in complications of disease.

SUMMARY

Advances in diagnostics, including pathogen identification as well as imaging continues to improve our ability to diagnose and treat these infections, although still lack ability to provide definitive diagnosis without more invasive nor advanced techniques.

Measures of Admission Immunocoagulopathy as an Indicator for In-Hospital Mortality in Patients with Necrotizing Fasciitis: A Retrospective Study

Necrotizing fasciitis is a rapidly progressive infection with a high mortality rate. Pathogens evade the host containment and bactericidal mechanisms by hijacking the coagulation and inflammation signaling pathways, leading to their rapid dissemination, thrombosis, organ dysfunction, and death. This study examines the hypothesis that measures of immunocoagulopathy upon admission could aid in the identification of patients with necrotizing fasciitis at high risk for in-hospital mortality.

Methods

Demographic data, infection characteristics, and laboratory values from 389 confirmed necrotizing fasciitis cases from a single institution were analyzed. A multivariable logistic regression model was built on admission immunocoagulopathy measures (absolute neutrophil, absolute lymphocyte, and platelet counts) and patient age to predict in-hospital mortality.

Results

The overall in-hospital mortality rate was 19.8% for the 389 cases and 14.6% for the 261 cases with complete measures of immunocoagulopathy on admission. A multivariable logistic regression model indicated that platelet count was the most important predictor of mortality, followed by age and absolute neutrophil count. Greater age, higher neutrophil count, and lower platelet count led to significantly higher risk of mortality. The model discriminated well between survivors and non-survivors, with an overfitting-corrected C-index of 0.806.

Conclusions

This study determined that measures of immunocoagulopathy and patient age at admission effectively prognosticated the in-hospital mortality risk of patients with necrotizing fasciitis. Given the accessibility of neutrophil-to-lymphocyte ratio and platelet count measurements determined from a simple complete blood-cell count with differential, future prospective studies examining the utility of these measures are warranted.

Level of Evidence

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Surveillance of osteoarticular infections caused by Staphylococcus aureus in a paediatric hospital in Mexico City

Staphylococcus aureus is the main aetiologic agent of osteoarticular infections (OAIs) in paediatric patients. The aim of this prospective unicenter study was to describe the phenotypic and genotypic characteristics of S. aureus isolates obtained from OAIs in paediatric patients admitted to tertiary care hospital. Through a surveillance program called OsteoCode, a multidisciplinary team was created and we identified 27 patients with OAIs caused by S. aureus from 2019 to 2021. The susceptibility profile, virulence factors, biofilm formation, pulsed-field gel electrophoresis (PFGE), clonal complex (CC) and sequence type (ST) were determined. In addition, the clinical characteristics and evolution of the patients presented six months after the diagnosis of OAIs were described. Ninety-two percent of the isolates were methicillin-sensitive S. aureus (MSSA). In methicillin-resistant S. aureus (MRSA), SCCmec-II and SCCmec-V were detected. The pvl gene was only observed in MSSA (18.5%) and was associated with highest fever (p=0.015), multiple localization (p=0.017), and soft tissue sites of infection beyond the bone (pyomyositis, pulmonary abscess) (p=0.017). Biofilm formation was detected in 55.6% of isolates. The most common CC were CC5 and CC30 which represent the most common linages for bone and joint infections worldwide. The isolates were distributed in different STs, and ST672 was predominant. MRSA were associated with a longer duration of intravenous treatment and a prolonged hospital stay (p=0.023). Recurrent infection occurred in five children and orthopaedic complications in 33.3% of patients. This is the first study that reflects the epidemiology of S. aureus in OAIs in paediatric patients in Mexico; a clear predominance of MSSA distributed in different STs was observed. Our findings highlight that a multidisciplinary team is required for the diagnosis and treatment of OAIs.

Fever and Knee Effusion in the Pediatric Patient

ABSTRACT

The pediatric patient with fever and knee effusion is always a cause for clinical concern. A thorough history and physical examination is required to guide appropriate diagnostic evaluation and management. Although pediatric knee effusions are common in the setting of trauma, the presence of fever should prompt consideration of infectious, rheumatologic, vasculitic, and malignant etiologies. This review covers the key components of the history, physical examination, diagnostic strategies, common etiologies, and initial management of the pediatric patient with fever and knee effusion.

Clinical report and predictors of sequelae of 319 cases of pediatric bacterial osteomyelitis

Pediatric osteomyelitis is an insidious disease that can lead to permanent sequelae, the management of which still relies on lengthy intravenous antibiotic therapy. The purpose of this study is to report and describe the clinical course and outcome of pediatric bacterial osteomyelitis in our experience. We reported the clinical, diagnostic, and treatment characteristics of all cases of osteomyelitis in children younger than 18 years of age who were hospitalized between January 2010 and December 2021 at the Bambino Gesù Children’s Hospital in Rome, Italy, we compared patients with and without complications at follow-up, to identify any predictive factor for sequelae. The study sample included 319 cases of pediatric bacterial osteomyelitis. The median age was 7.77 years. Males (60.8%) were more affected than females. The most affected bones were the femur, tibia, and spine. Etiology was identified in 40.1% of cases, with S.aureus as the most common causative agent. Sequelae were reported in 43 cases (13.5%). The main predictors of sequelae were sepsis on admission and hypergammaglobulinemia. Our results show that a severe presentation with sepsis and hypergammaglobulinemia on admission may be associated with a higher frequency of late sequelae. Early recognition and aggressive treatment of this subgroup of patients may lead to a reduction in complications.

Effects of prophylactic antibiotic administration and antibiotic timing on culture results and clinical outcomes of paediatric musculoskeletal infection: a protocol for a randomised controlled clinical trial

INTRODUCTION

Musculoskeletal infection (MSI) is a common cause of morbidity among the paediatric population. Some clinicians recommend withholding prophylactic antibiotics until culture collection with an aim to improve the culture sensitivity. However, a recent retrospective study reported that prophylactic antibiotic administration did not affect culture sensitivities in either disseminated or local MSI in paediatric population, which is surprising. The aim of the present study is to investigate the effects of prophylactic antibiotic administration and the timing of antibiotic administration on culture sensitivity and clinical outcomes of paediatric MSI.

METHODS AND ANALYSIS

A randomised controlled clinical trial will be carried out. Individuals aged 0-18 years with a diagnosis of MSI will be screened and evaluated at the Shenzhen Children's Hospital. The participants will be randomly allocated into four groups, and they will receive the antibiotic treatment at different time points, that is, 1 week, 3 days, 1 day prior to tissue culture collection and 1 day after tissue culture collection, respectively. The primary outcome will be culture sensitivity. In addition, the disease-related markers including white blood cell count, C reactive protein, erythrocyte sedimentation rate, vital signs as well as the length of hospital stay will be measured or recorded accordingly. Using χ² tests, the rates of positive cultures will be compared between different groups. Statistical comparisons between the different patient groups regarding the confounding and outcome variables will be conducted using independent t-tests, Mann-Whitney U tests, χ² tests and Fisher's exact tests as appropriate with the significance level set to 5% (p<0.05).

ETHICS AND DISSEMINATION

This study has received ethical approval. The findings will be disseminated both in scientific conferences and peer-reviewed journal.

TRIAL REGISTRATION NUMBER

ChiCTR2100041631.

Practice Variation in the Surgical Management of Children With Acute Hematogenous Osteomyelitis

INTRODUCTION

The surgical indications to manage children with acute hematogenous osteomyelitis (AHO) remain poorly defined. The purpose of this study was to identify if practice pattern variation exists in the surgical management of pediatric AHO among tertiary pediatric medical centers across the United States. A secondary purpose was to evaluate variables that may impact the rate of surgical intervention among these institutions.

METHODS

Children with AHO were retrospectively analyzed between January 1, 2010, and December 31, 2016, from 18 pediatric medical centers throughout the United States. The rates of surgery were identified. Admission vitals, labs, weight-bearing status, length of stay, and readmission rates were compared between those who did and did not undergo surgery. Multivariate regression and classification and regression tree analyses were performed to identify the variables that were associated with surgical intervention.

RESULTS

Of the 1003 children identified with AHO in this retrospective, multicenter database, 619/1003 (62%) were treated surgically. Multivariate analysis revealed institution, inability to ambulate, presence of multifocal infection, elevated admission C-reactive protein, increased admission platelet count, and location of the osteomyelitis were significant predictors of surgery (P<0.01). Patients who underwent surgery were more than twice as likely to have a recurrence or readmission and stayed a median of 2 days longer than those who did not have surgery. In the classification and regression tree analysis, 2 distinct patterns of surgical intervention were identified based on institution, with 12 institutions operating in most cases (72%), regardless of clinical factors. A second cohort of 6 institutions operated less routinely, with 47% receiving surgery overall. At these 6 institutions, patients without multifocal infection only received surgery 26% of the time, which increased to 74% with multifocal infection and admission erythrocyte sedimentation rate >37.5 mm/h.

CONCLUSIONS

This study is the first to objectively identify significant differences in the rates of surgical management of pediatric AHO across the United States. Variation in the surgical management of AHO appears to be driven primarily based on institutional practice. Twelve institutions operated on 72% of patients, regardless of the severity of disease, indicating that the institution custom or dogma may drive the surgical indications. Six institutions relied more on clinical judgment with significant variability in rates of surgical intervention (26% vs. 74%), depending on the severity of the disease. Surgical intervention is associated with increased recurrence, readmission, and hospital length of stay. As a result of these findings, it is essential to prospectively study the appropriate surgical indications and measure the outcomes in children with pediatric AHO.

LEVEL OF EVIDENCE

Level III.

ACR Appropriateness Criteria® Osteomyelitis or Septic Arthritis-Child (Excluding Axial Skeleton)

Imaging plays an integral role in the evaluation of suspected musculoskeletal infections in children, not only in the accurate identification of infection such as osteomyelitis or septic arthritis, but also in guiding management. Various diagnostic modalities serve different purposes in the assessment of suspected pediatric musculoskeletal infections. The purpose of this document is to provide imaging guidance in the most frequently encountered clinical scenarios in which osteomyelitis and/or septic arthritis are suspected, outside of the axial skeleton. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion.

Osteomyelitis of the Rib in a Child With Indolent Symptoms

We describe a case of osteomyelitis of the rib caused by methicillin-susceptible Staphylococcus aureus. The patient presented with a subtle, indolent course leading to a suspected 2-year delay in diagnosis. This case highlights that the diagnosis of rib osteomyelitis, which can readily mimic other diagnoses, such as costochondritis, intraabdominal infections, pneumonia, or malignancies warrants a high index of suspicion. Albeit rare, pediatricians should be aware of the possibility of rib osteomyelitis in healthy children to help ensure a prompt diagnosis and appropriate, timely management.

Surgery's role in contemporary osteoarticular infection management

The treatment paradigm for osteoarticular infections (OAIs) has changed drastically over the past 80 years, from the advent of penicillin to the use of broad-spectrum antibiotics. Before these drugs, surgery was the only available treatment for OAIs; today, antibiotic therapy is considered the primary response to them. As a result, surgical treatment of OAIs is thus far more rarely indicated, sometimes even considered outdated and obsolete. However, long experience has taught us that many OAI contexts can still benefit from surgical management, constituting an essential complement to medical treatment. The present article seeks to contextualize this discussion by providing a chronological review of the surgical treatments used in cases of OAI and describing the quality of evidence supporting their rehabilitation in well-established situations.

Osteomyelitis in Immunocompromised children and neonates, a case series

BACKGROUND

Osteomyelitis in immunocompromised children can present differently from immunocompetent children and can cause devastating sequelae if treated inadequately. We aim to review the aetiology, clinical profile, treatment and outcomes of immunocompromised children with osteomyelitis.

METHODS

Retrospective review of all immunocompromised children aged < 16 years and neonates admitted with osteomyelitis in our hospital between January 2000 and January 2017, and referred to the Paediatric Infectious Disease Service.

RESULTS

Fourteen patients were identified. There were 10 boys (71%), and the median age at admission was 70.5 months (inter-quartile range: 12.3-135.0 months). Causal organisms included, two were Staphylococcus aureus, two were Mycobacterium bovis (BCG), and one each was Mycobacterium tuberculosis, Pseudomonas aeruginosa, Stenotrophomonas maltophilia, Burkholderia pseudomallei and Rhizopus sp. One patient had both Clostridium tertium and Clostridium difficile isolated. Treatment involved appropriate antimicrobials for a duration ranging from 6 weeks to 1 year, and surgery in 11 patients (79%). Wherever possible, the patients received treatment for their underlying immunodeficiency. For outcomes, only three patients (21%) recovered completely. Five patients (36%) had poor bone growth, one patient had recurrent discharge from the bone and one patient had palliative care for underlying osteosarcoma.

CONCLUSIONS

Although uncommon, osteomyelitis in immunocompromised children and neonates can be caused by unusual pathogens, and can occur with devastating effects. Treatment involves prolonged administration of antibiotics and surgery. Immune recovery also seems to be an important factor in bone healing.

Pediatric Musculoskeletal Infections: Imaging Guidelines and Recommendations

Pediatric musculoskeletal infections often pose a diagnostic challenge due to their frequently vague and nonspecific clinical presentation. Imaging evaluation is a crucial component to diagnostic workup of these entities. Changed epidemiology of these infections over the past 2 decades has resulted in increases in both disease incidence and severity in the pediatric population. Prompt and accurate diagnosis is essential in order to reduce the risk of morbid sequelae, and to optimize patient management. In this article, the unique pathophysiology of musculoskeletal infections and characteristic imaging findings in children compared with adults are reviewed.

The Epidemiology of Osteomyelitis in Children

Pediatric osteomyelitis remains challenging to treat. Detailed epidemiological data are required to estimate future developments. Therefore, we aimed to analyze how the incidence has changed over the last decade depending on age, gender, osteomyelitis subtype, and anatomical localization. Cases were quantified for patients aged 20 years or younger, using yearly reported ICD-10 diagnosis codes from German medical institutions for the time period 2009 to 2019. Incidence rates of osteomyelitis increased by 11.7% from 8.2 cases per 100,000 children in 2009 to 9.2 cases per 100,000 children in 2019. The age-specific incidence rate revealed the highest occurrence of osteomyelitis in patients aged 10–15 years (15.3/100,000 children), which increased by 23% over the observation period, followed by the age group 5–10 years (9.7/100,000 children). In 2019, out of all diagnoses, 39.2% were classified as acute, 38.4% as chronic, and 22.4% were unspecified, whereby chronic cases increased by 38.7%. The lower extremity was mainly affected, with 58.9% of osteomyelitis diagnoses in 2019. In conclusion, pediatric osteomyelitis is a serious issue, even in a developed and industrialized country such as Germany. Considering the recent incidence increase, the permanent need for appropriate treatment should let pediatricians and orthopedic surgeons deal with diagnosis and treatment protocols.

PET/MRI in paediatric disease

Nuclear medicine and molecular imaging have a small but growing role in the management of paediatric and neonatal diseases. During the past decade, combined PET/MRI has emerged as a clinically important hybrid imaging modality in paediatric medicine due to diagnostic advantages and reduced radiation exposure compared to alternative techniques. The applications for nuclear medicine, radiopharmaceuticals and combined PET/MRI in paediatric diagnosis is broadly similar to adults, however there are some key differences. There are a variety of clinical applications for PET/MRI imaging in children including, but not limited to, oncology, neurology, cardiovascular, infection and chronic inflammatory diseases, and in renal-urological disorders. In this article, we review the applications of PET/MRI in paediatric and neonatal imaging, its current role, advantages and disadvantages over other hybrid imaging techniques such as PET/CT, and its future applications. Overall, PET/MRI is a powerful imaging technology in diagnostic medicine and paediatric diseases. Higher soft tissue contrasts and lower radiation dose of the MRI makes it the superior technology compared to other conventional techniques such as PET/CT or scintigraphy. However, this relatively new hybrid imaging has also some limitations. MRI based attenuation correction remains a challenge and although methodologies have improved significantly in the last decades, most remain under development.

Clinical Practice Guideline by the Pediatric Infectious Diseases Society and the Infectious Diseases Society of America: 2021 Guideline on Diagnosis and Management of Acute Hematogenous Osteomyelitis in Pediatrics

This clinical practice guideline for the diagnosis and treatment of acute hematogenous osteomyelitis (AHO) in children was developed by a multidisciplinary panel representing Pediatric Infectious Diseases Society (PIDS) and the Infectious Diseases Society of America (IDSA). This guideline is intended for use by healthcare professionals who care for children with AHO, including specialists in pediatric infectious diseases, orthopedics, emergency care physicians, hospitalists, and any clinicians and healthcare providers caring for these patients. The panel's recommendations for the diagnosis and treatment of AHO are based upon evidence derived from topic-specific systematic literature reviews. Summarized below are the recommendations for the diagnosis and treatment of AHO in children. The panel followed a systematic process used in the development of other IDSA and PIDS clinical practice guidelines, which included a standardized methodology for rating the certainty of the evidence and strength of recommendation using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) approach. A detailed description of background, methods, evidence summary and rationale that support each recommendation, and knowledge gaps can be found online in the full text.

Culture-negative chronic hematogenous osteomyelitis in a two months old girl: a case report

Background

Previous articles have focused on the diagnosis and treatment of acute hematogenous osteomyelitis. Here, we present a case of chronic hematogenous osteomyelitis in a 2-month-old girl. The diagnostic procedure was unusual and difficult due to negative culture results.

Case presentation

A girl aged 2 months and 23 days had fever and swelling in her right lower leg for 7 days. On the basis of her medical history, physical, and histological examination results; and radiologic and magnetic resonance imaging findings, a diagnosis of chronic osteomyelitis was made. The patient underwent surgical treatment and was discharged successfully. The patient showed good recovery and no sequelae at the 12-month follow-up.

Conclusion

Hematogenous osteomyelitis in babyhood is different from that at any other age. Hematogenous osteomyelitis-related bone destruction in babyhood is more serious and occurs faster. The transition from acute hematogenous osteomyelitis to chronic hematogenous osteomyelitis takes only 7 days. To the best of our knowledge, this chronic hematogenous osteomyelitis patient is the youngest ever reported.

Radiological changes in the formation of Brodie's abscess by sequential magnetic resonance imaging: a case report

Brodie's abscess is a relatively rare subacute form of osteomyelitis. Early diagnosis is challenging because of its insidious onset and vague symptoms. Magnetic resonance imaging is helpful in the diagnosis of Brodie's abscess; however, to date, no study has described the imaging findings of this disease in the early stage. Here, we present the case of a 14 year-old boy with Brodie's abscess in the proximal tibia. The lesion initially presented as a bone marrow edema in the proximal metaphysis of the left tibia on MRI and was misinterpreted as a bone bruise. Further radiological examination was performed 1 month later; this revealed the formation of an abscess cavity, which suggested Brodie's abscess. The patient was referred to our hospital and underwent curettage and debridement, which led to the definitive diagnosis of Brodie's abscess on histopathological findings and bacterial culture. On careful retrospective evaluation, the initial radiological findings suggested a microabscess on the metaphyseal side of the growth plate and bone marrow edema spreading from the lesion to the epiphysis. These radiological changes could be reliable evidence proving that the metaphyseal side of the growth plate is the origin of Brodie's abscess. Moreover, bone marrow edema with suspected microabscess in the metaphysis of the long bones can be the initial stage of the formation of Brodie's abscess and should be carefully followed up.

Fusobacterial Pelvic Osteomyelitis with Brodie's Abscess in a 10-Year-Old Boy Requiring Surgical Evacuation: A Case Report

CASE

A 10-year-old boy presented with pain in the lateral hip and buttock area and fever. Magnetic resonance imaging revealed osteomyelitis of the pelvis with extensive Brodie's abscess (2.6 × 4.5 × 10.0 cm) continuing into the pelvic cavity. Surgical evacuation through the ilioinguinal approach was performed. In prolonged culture and in polymerase chain reaction of pus, the Fusobacterium nucleatum was found.

CONCLUSION

Pelvic osteomyelitis caused by Fusobacterium is very rare. In this case, surgical treatment was required after conservative treatment with antibiotics was ineffective.

What is the burden of osteomyelitis in Germany? An analysis of inpatient data from 2008 through 2018

Background

The epidemiology of osteomyelitis in Germany is unknown, which makes it difficult to estimate future demands. Therefore, we aimed to analyse how the numbers of cases have developed over the last decade as a function of osteomyelitis subtype, age group, gender, and anatomical localization.

Methods

Osteomyelitis rates were quantified based on annual ICD-10 diagnosis codes from German medical institutions between 2008 through 2018, provided by the Federal Statistical Office of Germany (Destatis).

Results

Overall osteomyelitis prevalence increased by 10.44% from 15.5 to 16.7 cases per 100,000 inhabitants between 2008 through 2018. Out of 11,340 cases in 2018, 47.6% were diagnosed as chronic, 33.2% as acute and 19.2% as unspecified osteomyelitis. Men were often affected than women with 63.4% of all cases compared to 36.6%. The largest proportion of patients comprised the age group 60–69 years (22.1%), followed by 70–79 years (21.7%). A trend towards more osteomyelitis diagnoses in older patients was observed. Lower extremities were most frequently infected with 73.8% of all cases in 2018 (+ 10.8% change).

Conclusions

Osteomyelitis remains a serious problem for orthopedic and trauma surgery. Prevention methods and interdisciplinary approaches are strongly required.

Contemporary clinical isolates of Staphylococcus aureus from pediatric osteomyelitis patients display unique characteristics in a mouse model of hematogenous osteomyelitis

Osteomyelitis can result from the direct inoculation of pathogens into bone during injury or surgery, or from spread via the bloodstream, a condition called hematogenous osteomyelitis (HOM). HOM disproportionally affects children, and more than half of cases are caused by Staphylococcus (S.) aureus. Laboratory models of osteomyelitis mostly utilize direct injection of bacteria into the bone or the implantation of foreign material, and therefore do not directly interrogate the pathogenesis of pediatric hematogenous osteomyelitis. In this study, we inoculated mice intravenously and characterized resultant musculoskeletal infections using two strains isolated from adults (USA300-LAC and NRS384) and five new methicillin-resistant S. aureus isolates from pediatric osteomyelitis patients. All strains were capable of creating stable infections over five weeks, although the incidence varied. Micro-computed tomography (microCT) analysis demonstrated decreases in trabecular bone volume fraction but little effect on bone cortices. Histologic assessment revealed differences in the precise focus of musculoskeletal infection, with varying mixtures of bone-centered osteomyelitis and joint-centered septic arthritis. Whole genome sequencing of three new isolates demonstrated distinct strains, two within the USA300 lineage and one USA100 isolate. Interestingly, this USA100 isolate showed a distinct predilection for septic arthritis, compared to the other isolates tested, including NRS384 and LAC, which more frequently led to osteomyelitis or mixed bone and joint infections. Collectively, these data outline the feasibility of using pediatric osteomyelitis clinical isolates to study the pathogenesis of HOM in murine models and lay the groundwork for future studies investigating strain-dependent differences in musculoskeletal infection.

Neonatal osteomyelitis: an Italian multicentre report of 22 cases and comparison with the inherent literature

OBJECTIVE

The primary objective of this study is to report and compare our data with the most relevant literature of the past decade about neonatal osteomyelitis.

STUDY DESIGN

We retrospectively review the data of 22 subjects aged 35 days or less who were admitted to three different sites in Italy with a radiological diagnosis of osteomyelitis. The inherent literature was searched and reviewed: five studies were considered for comparison with our data.

RESULTS

All the neonates, except three (two pre-term and one post-term), were born at term. The male to female ratio was 1.75 (14 males and 8 females). The mean age at presentation was 19.5 days. The most common presenting signs of the infection were local swelling and reduced mobility of the affected segment. The most common sites of infection were the femur, humerus, and tibia. The mean duration of intravenous antibiotic therapy was 29.5 days. In most neonates the diagnosis was prompt and the antibiotic treatment immediate. A low rate of sequelae was reported. All infants survived through follow up. The data from the inherent literature showed a wide variability, probably owing to the setting and the historical period of the different studies.

CONCLUSION

Neonatal osteomyelitis is an alarming yet poorly understood disease. Nonetheless, our report suggests that a quick diagnosis and treatment can be easily achieved, with good outcome on the remarkably plastic structure of neonatal bones.

Updates and Advances: Pediatric Musculoskeletal Infection Imaging Made Easier for Radiologists and Clinicians

Infants and children often present with a wide range of musculoskeletal (MSK) infections in daily clinical practice. This can vary from relatively benign superficial infections such as cellulitis to destructive osseous and articular infections and life-threatening deep soft tissue processes such as necrotizing fasciitis. Imaging evaluation plays an essential role for initial detection and follow-up evaluation of pediatric MSK infections. Therefore, a clear and up-to-date knowledge of imaging manifestations in MSK infections in infants and children is imperative for timely and accurate diagnosis that, in turn, can result in optimal patient management. This article reviews an up-to-date practical imaging techniques, the differences between pediatric and adult MSK infections, the spectrum of pediatric MSK infections, and mimics of pediatric MSK infections encountered in daily clinical practice by radiologists and clinicians.

Pediatric Acetabular Osteomyelitis Treated With Hip Arthroscopy

Osteomyelitis of the acetabulum is a rare condition accounting for only 12% of pelvic osteomyelitis cases. This report describes a previously healthy 10-year-old girl with subacute acetabular osteomyelitis and subsequent development of secondary septic arthritis of the hip. The patient presented with 3 weeks of groin pain, elevated erythrocyte sedimentation rate and C-reactive protein, synovial thickening of the hip on ultrasonography and diffuse signal uptake in the acetabulum on magnetic resonance imaging. Despite antibiotic therapy, her symptoms worsened clinically, and repeat Magnetic resonance imaging images showed worsening of the osteomyelitis with likely extension through the acetabulum and into the joint. A hip aspirate was positive for Fusobacterium, an atypical anaerobe. Hip arthroscopy, with identification of the site of extrusion and then extensive débridement and irrigation, was successful in helping to control and ultimately eradicate the infection. The patient regained normal hip function and returned to full activities. This case demonstrates how hip arthroscopy can serve as an important surgical treatment modality for acetabular osteomyelitis with intraarticular extension in addition to septic arthritis of the hip.

Unremitting Pain and Fever in a 15-Year-Old Boy With Osteomyelitis

A previously healthy 15-year-old boy from a rural county in the southeastern United States was evaluated in the emergency department with fever and worsening toe pain in the absence of trauma. He initially presented to his primary care physician 4 weeks before with upper respiratory symptoms and was treated with corticosteroids for presumed reactive airway disease. His respiratory symptoms resolved. One week after this presentation, he developed fever and right great toe pain and presented to an outside hospital. Inflammatory markers were elevated. MRI confirmed a diagnosis of osteomyelitis with associated periosteal abscess. He was treated with intravenous antibiotics and drainage of the abscess. Ten days after his discharge from the outside hospital, he developed fever and had increasing drainage of the toe and pain refractory to oral pain medications. He presented to our facility for further evaluation. Repeat MRI and inflammatory markers corroborated his worsening disease, and he was admitted to the hospital for intravenous antibiotics and underwent serial surgical debridement. He developed painful subcutaneous nodules on his lower extremities and was found to have lung abnormalities on chest radiograph. A multispecialty team collaborated in the management of this patient and unveiled a surprising diagnosis.

Improving Care and Outcomes for Pediatric Musculoskeletal Infections

BACKGROUND

Pediatric musculoskeletal infection (MSKI) is a common cause of hospitalization with associated morbidity. To improve the care of pediatric MSKI, our objectives were to achieve 3 specific aims within 24 months of our quality improvement (QI) interventions: (1) 50% reduction in peripherally inserted central catheter (PICC) use, (2) 25% reduction in sedations per patient, and (3) 50% reduction in empirical vancomycin administration.

METHODS

We implemented 4 prospective QI interventions at our tertiary children's hospital: (1) provider education, (2) centralization of admission location, (3) coordination of radiology-orthopedic communication, and (4) implementation of an MSKI infection algorithm and order set. We included patients 6 months to 18 years of age with acute osteomyelitis, septic arthritis, or pyomyositis and excluded patients with complex chronic conditions or ICU admission. We used statistical process control charts to analyze outcomes over 2 general periods: baseline (January 2015-October 17, 2016) and implementation (October 18, 2016-April 2019).

RESULTS

In total, 224 patients were included. The mean age was 6.1 years, and there were no substantive demographic or clinical differences between baseline and implementation groups. There was an 81% relative reduction in PICC use (centerline shift 54%-11%; 95% confidence interval 70-92) and 33% relative reduction in sedations per patient (centerline shift 1.8-1.2; 95% confidence interval 21-46). Empirical vancomycin use did not change (centerline 20%).

CONCLUSIONS

Our multidisciplinary MSKI QI interventions were associated with a significant decrease in the use of PICCs and sedations per patient but not empirical vancomycin administration.

Whole-body MRI in the diagnosis of paediatric CNO/CRMO

Chronic recurrent multifocal osteomyelitis (CRMO) is an auto-inflammatory disorder affecting the skeleton of children and adolescents. Whole-body MRI (WBMRI) is key in the diagnosis and follow-up of CRMO. Imaging protocols should include sagittal short Tau inversion recovery of the spine, imaging of the hands and feet, and T1 images for distinguishing normal bone marrow. CRMO lesions can be metaphyseal, epiphyseal and physeal-potentially causing growth disturbance and deformity. Spinal lesions are common, important and can cause vertebral collapse. Lesion patterns include multifocal tibial and pauci-focal patterns that follow a predictable presentation and course of disease. Common pitfalls of WBMRI include haematopoietic marrow signal, metaphyseal signal early on in bisphosphonate therapy and normal high T2 signal in the hands and feet. Pictorial reporting assists in recording lesions and follow-up over time. The purpose of this paper is to review the different WBMRI protocols, imaging findings, lesion patterns and common pitfalls in children with CRMO.

Acute hematogenous osteomyelitis in pediatric patients: epidemiology and risk factors of a poor outcome

Objective

Methods

Results

Conclusions

A Comparison of the Epidemiology, Clinical Features, and Treatment of Acute Osteomyelitis in Hospitalized Children in Latvia and Norway

Background and objectives: Paediatric acute osteomyelitis (AO) may result in major life-threatening and limb-threatening complications if not recognized and treated early. The management of AO may depend on local microbial prevalence and virulence factors. This study compares the approach to paediatric AO in hospitals in two countries—Latvia and Norway. Materials and Methods: The study includes patients with AO hospitalized in the paediatric department in the Norwegian hospital Sørlandet Sykehus Kristiansand (SSK), in the period between the 1st of January 2012 and the 31st of December 2019. The results from SSK are compared to the results of a published study of AO in patients hospitalized at the Children’s Clinical University Hospital (CCUH) in Riga, Latvia. Results: The most isolated pathogen from cultures in both hospitals was S. aureus (methicillin-sensitive). The lower extremity was the most affected body part (75% in CCUH, 95% in SSK), the main clinical symptom was pain (CCUH 92%, SSK 96.6%). Deep culture aspiration was most often taken intraoperatively in CCUH (76.6%) and percutaneously in SSK (44.8%). Oxacillin was the most applied antibiotic in CCUH (89.4%), and Cloxacillin in SSK (84.6%). Combined treatment with anti-Staphylococcal penicillins and Clindamycin was administered in 25.5% and 33.8% of CCUH and SSK patients, respectively. The median duration of the intravenous antibacterial treatment in CCUH and SSK was 15 and 10 days, respectively, and a switch to oral therapy was mainly made at discharge in both hospitals. The median total duration of antibiotic treatment was 25 days in CCUH and 35 days in SSK. 75% of CCUH and 10.3% of SSK patients were treated surgically. Complications were seen in 47% of patients in CCUH and in 38% in SSK. Conclusions: The transition to oral antibacterial treatment in both hospitals was delayed, which suggests a lack of criteria for discontinuation of intravenous therapy and could potentially contribute to longer hospitalization, higher cost of treatment and risk of complications. The use of more invasive techniques for deep culturing and significantly more common surgical interventions could possibly be linked to a higher complication rate in AO patients treated at the Latvian hospital.

Spondylodiscitis in Children: A Retrospective Study and Comparison With Non-vertebral Osteomyelitis

Objectives: The aim of this study is to provide new data on pediatrics spondylodiscitis for an optimal clinical management of this site-specific osteomyelitis. Methods: We reported 48 cases of pediatric spondylodiscitis and made three comparisons between: (1) tubercular and non-tubercular cases; (2) patients aged more or less than 5 years; (3) children with spondylodiscitis and 62 controls with non-vertebral osteomyelitis. Results: A higher rate of sequelae was reported in patients with tubercular spondylodiscitis, but no significant differences were noted at the cut-off of 5 years of age. Compared to non-vertebral osteomyelitis, pediatric spondylodiscitis affects younger children of both genders, usually presenting with afebrile back pain, and requiring longer time to admission, hospitalization, and antibiotic therapy. Conclusion: Pediatric spondylodiscitis is an insidious disease with a non-specific presentation in childhood and peculiarities of its own. However, when clinical remission is obtained by an early start of broad-spectrum antibiotics, prolonging the therapy does not improve, nor worsens, the outcome. Surgical management is mandatory in case of vertebral instability and neurological signs but can be avoided when the infection is promptly treated with antibiotic therapy.

Acute Hematogenous Osteomyelitis in Children: Clinical Presentation and Management

Acute hematogenous osteomyelitis (AHO) is a common invasive infection encountered in the pediatric population. In addition to the acute illness, AHO has the potential to create long-term morbidity and functional limitations. While a number of pathogens may cause AHO, Staphylococcus aureus is the most common organism identified. Despite the frequency of this illness, little high-quality data exist to guide providers in the care of these patients. The literature is reviewed regarding the epidemiology, microbiology and management of AHO in children. A framework for empiric therapy is provided drawing from the available literature and published guidelines.

A 10-year retrospective survey of acute childhood osteomyelitis in Stockholm, Sweden

AIM

Children with osteomyelitis present with a range of signs and symptoms and with varying degree of severity. The purpose of this study was to provide data on a population-based 10-year material of children with acute osteomyelitis.

METHODS

All children, 0-14 years in Stockholm Region with acute osteomyelitis hospitalised in July 2005-June 2015, were retrospectively studied. Time to hospital presentation, disease localization, inflammation markers, imaging procedures, microbiology, severity classified by the presence of complications, surgical procedures, hospital length of stay and seasonal variation were recorded.

RESULTS

There were 430 children with acute osteomyelitis; 61% were boys. The incidence per 100 000 person-years was 11.6; 9.3 in girls and 13.1 in boys. Median age at admission was 2.9 years with no peak later in childhood. Median time from first symptom to diagnosis was 4 days (range 1-21) and 48% of the cases were localised to femur or tibia. Mean C-reactive protein was 59 mg/L (range 1-376). Blood (n = 82) or tissue cultures (n = 54) were positive in 118 (28%) children. The most common pathogen was Staphylococcus aureus (n = 88) followed by Streptococcus pyogenes (n = 12). Surgery was performed in 71 children (17%). There was no mortality. Severe complications were seen in 14 (3.3%) children, five of whom were admitted to intensive care. Median hospital length of stay was 4 days (range 1-60).

CONCLUSIONS

Osteomyelitis in children is a diagnostic challenge with a low yield of positive bacterial cultures. Few children with uncomplicated disease need surgery, but the risk of severe complications is not negligible.

Existing and emerging methods of diagnosis and monitoring of pediatric musculoskeletal infection

Methods of diagnosing and monitoring pediatric musculoskeletal infections are rapidly evolving. Key serologic tests are typically used in screening patients with suspected infections, and remain an integral part of the initial work-up. Synovial studies from arthrocentesis in possible septic arthritis, and source-specific cultures have been the foundation of our treatment algorithm. Given the prevalence of soft tissue abscesses and osteoarticular infections, advanced imaging is an advantageous tool. More affordable use and expanded access to MRI has made it a valuable adjunct to clinical picture and existing tests in order to comprehensively visualize the extent of musculoskeletal infections in children. Ongoing validation for criteria to help determine the patients that stand to benefit the most from MRI, even when surgical intervention may be delayed, remains of significant clinical interest. Given the rates of culture-negative infections, and the need for timely diagnosis, new diagnostic techniques are always being considered. The search for more accurate biomarkers, and technology such as Whole genome sequencing (WGS) and next-generation sequencing (NGS) that can rapidly identify pathogens of all types of phyla based on a small sample of DNA, has promising clinical implications. While once novel and prohibitively expensive, these tests are now being applied in university and tertiary care centers in certain scenarios. Applying these techniques to pediatric musculoskeletal will require a large change in lab workflow and training. However, the benefits of acquiring diagnostic information along with will make them a superior tool in our arsenal of diagnostic tests.

Diagnosing and treating native spinal and pelvic osteomyelitis in adolescents

STUDY DESIGN

Retrospective case series.

OBJECTIVES

To describe how pediatric patients with spinal and pelvic osteomyelitis are diagnosed and treated and assess the diagnostic value of magnetic resonance imaging (MRI), needle aspiration biopsy (NAB), and blood cultures in this population. Spinal and pelvic osteomyelitis de novo are uncommon in children and minimal literature exists on the subject. Research has shown that NAB and blood cultures have variable diagnostic yield in adult native osteomyelitis. At our institution, there is no standard protocol for diagnosing and treating pediatric spinal and pelvic osteomyelitis de novo.

METHODS

All diagnoses of spinal and pelvic osteomyelitis at a pediatric tertiary care center from 2003 to 2017 were reviewed. Patients aged 0-21 at diagnosis were included. Patients with osteomyelitis resulting from prior spinal operations, wounds, or infections and those with chronic recurrent multifocal osteomyelitis were eliminated. All eligible patients' diagnoses were confirmed by MRI.

RESULTS

29 patients (18 men, 11 women) met the inclusion criteria. The median age at diagnosis was 11 years old (range 1-18). More than half of all cases (17/29, 59%) affected the lumbar spine. The most common symptoms were back pain (20/29, 69%), fever (18/29, 62%), hip pain (11/29, 38%), and leg pain (8/29, 28%). The majority of NABs and blood cultures performed were negative, but of the positive tests Staphylococcus aureus was the most prevalent bacteria. 86% (25/29) had an MRI before a diagnosis was made and 72% (13/18) had an NAB performed post-diagnosis.

CONCLUSIONS

MRI is a popular and helpful tool in diagnosing spinal osteomyelitis de novo. NAB cultures are often negative but can be useful in determining antibiotic treatment.

LEVEL OF EVIDENCE

Level IV.

Short-course antibiotic treatment of bone and joint infections in children: a retrospective study at Montpellier University Hospital from 2009 to 2013

BACKGROUND

Acute haematogenous bone and joint infections (AHBJI) represent a diagnostic and therapeutic emergency in children, with significant potential sequelae in the case of delayed treatment. Although historically the recommendations for treatment have been based on surgery and prolonged antibiotic therapy, recent studies have demonstrated that short-course antibiotic therapy is also effective.

OBJECTIVES

We evaluated a short-term antibiotic protocol for both osteomyelitis and septic arthritis in a 6 year retrospective study at the University Hospital of Montpellier.

METHODS

This protocol was based on an initial intravenous treatment with a re-evaluation after 48 h and an early switch to oral therapy in the case of a favourable clinical course for a minimum total duration of 15 days. Antibiotics were selected based on local microbiological epidemiology and systematically adapted to bacteriological results.

RESULTS

One hundred and seventy-six cases of AHBJI were included, comprising 56 patients with osteomyelitis, 95 with septic arthritis and 25 who had both of these. The aetiological agent was identified in 42% of the cases, with the main pathogens being Staphylococcus aureus (39%) and Kingella kingae (27%). The mean intravenous treatment duration was 4 days, while the total treatment duration was 15 days. There were no treatment failures, mild sequelae occurred in 1% of the cases and the secondary surgical revision rate was 7%.

CONCLUSIONS

The results of this study are comparable to those reported for evaluations of prolonged antibiotic therapy protocols, thus indicating that a common short-term antimicrobial therapy for the management of both osteomyelitis and septic arthritis (minimum of 15 days) is a viable option for treating AHBJI in children. Further prospective studies to confirm these findings are hence warranted.

Clinical and Microbiologic Variables Predictive of Orthopedic Complications Following Staphylococcus aureus Acute Hematogenous Osteoarticular Infections in Children

BACKGROUND

Staphylococcus aureus is the most common cause of acute hematogenous osteoarticular infections (AHOAIs) in children. The risk factors for the development of orthopedic complications (OC) after AHOAI are poorly understood. We sought to describe clinical and microbiologic variables present on the index admission that may predict OC in S. aureus AHOAI.

METHODS

Staphylococcus aureus AHOAI cases were identified from 2011-2017 at Texas Children's Hospital and reviewed for the development of OC. OC included chronic osteomyelitis, growth arrest, avascular necrosis, chronic dislocation, and pathologic fracture. All S. aureus isolates were characterized by pulsed-field gel electrophoresis and agr group.

RESULTS

A total of 286 cases were examined of which 27 patients (9.4%) developed OC. Patients who developed OC more often had infection with an agr group III organism (P = .04), bacteremia (P = .04), delayed source control (P < .001), ≥2 surgical procedures (P < .001), intensive care unit admission (P = .09), and fever >4 days after admission (P = .008). There was no association with OC and patient age, methicillin resistance, or choice/route of antibiotics. In multivariable analyses of OC, infection with agr group III S. aureus, prolonged fever, and delayed source control remained statistically significant.

CONCLUSIONS

OC develop following S. aureus AHOAI in 9.4% of cases. Although the development of OC is likely multifactorial, agr group III organisms, prolonged fever, and delayed source control are independently associated with OC. Moreover, early aggressive surgical source control may be beneficial in children with S. aureus AHOAI.

Acute osteomyelitis of the distal fibula in children: Treatment options and long-term follow-up

INTRODUCTION

Acute osteomyelitis of the distal fibula is a rare disease in children and is characterized by special features compared with other sites. The objective of this study was to report the functional outcome at long-term follow-up.

METHODS

We reviewed retrospectively, between January 2000 and December 2010, all cases of acute osteomyelitis of the distal fibula. Epidemiological and bacteriological data as well as therapy and outcome factors were analyzed. At the last follow-up, functional outcome was studied based on ankle motion, growth disturbance, and radiological sequelae.

RESULTS

Seven cases of acute osteomyelitis of the distal fibula were found. The mean age was patients was 7.71 years and the sex ratio was 2.5. The portal of entry of the pathogen was a skin injury in 57% of cases. Staphylococcusaureus was identified in 71% of cases. The mean duration of antibiotic therapy was 33.2 days. At a mean of 12.85 years of follow-up, no growth disturbance was found. The mean plantar and dorsal flexion was 41° and 27.7°, respectively. The mean postoperative American Orthopedics Foot and Ankle score (AOFAS) was 96.71 points.

CONCLUSION

Acute osteomyelitis of the distal fibula in children is scarce and rarely reported in the literature. It occurs more often in boys at an average age of 7 years. Local symptoms are usually more obvious than general symptoms. Surgical debridement of the subperiosteal abscess without bone trepanation seems to lead to a satisfactory outcome.

LEVEL OF EVIDENCE

Level IV - case series. IRB: Sahloul Hospital Human Research Ethics Committee.

NF-κB/TWIST1 Mediates Migration and Phagocytosis of Macrophages in the Mice Model of Implant-Associated Staphylococcus aureus Osteomyelitis

Staphylococcus aureus (S. aureus) infection-induced osteomyelitis is a great challenge in clinic treatment. Identification of the essential genes and biological processes that are specifically changed in mononuclear cells at an early stage of S. aureus osteomyelitis is of great clinical significance. Based on transcriptional dataset GSE16129 available publicly, a bioinformatic analysis was performed to identify the differentially expressed genes of osteomyelitis caused by S. aureus infection. ERBB2, TWIST1, and NANOG were screened out as the most valuable osteomyelitis-related genes (OMRGs). A mice model of implant-associated S. aureus osteomyelitis was used to verify the above genes. We found significantly up-regulated expression of TWIST1 in macrophages and accumulation of macrophages around the infected implant. Meanwhile, S. aureus infection increased the expression of TWIST1, MMP9, and MMP13, and stimulated the migration and phagocytosis function of Raw 264.7 cells. Additionally, knock-down of the expression of TWIST1 by siRNA could significantly down-regulate MMP9 and MMP13 and suppress the migration and phagocytosis ability of macrophages in response to S. aureus infection. Furthermore, we found that NF-κB signaling was activated in Raw 264.7 cells by S. aureus and that inhibition of NF-κB signaling by Bay11-7082 blocked the expression of TWIST1, MMP9, and MMP13 as well as cell migration and phagocytosis evoked by S. aureus. Our findings demonstrate that NF-κB/TWIST1 is necessary for migration and phagocytosis of macrophages in response to S. aureus infection. Our study highlights the essential role of NF-κB/TWIST1 in early innate immune response to S. aureus infection in bone.