Current Concepts in Pediatric Septic Arthritis

Native and prosthetic septic arthritis in a university hospital in Saudi Arabia: A retrospective study

BACKGROUND

Septic arthritis, whether native or prosthetic, poses a significant challenge in clinical practice due to its potentially devastating consequences. Despite its clinical importance, there remains a dearth of comprehensive studies and standardized diagnostic criteria, particularly in the Kingdom of Saudi Arabia.

AIM

To investigate the epidemiology, microbiological profiles, and clinical characteristics of native and prosthetic septic joints in the Saudi Arabian population.

METHODS

Medical records of patients diagnosed with septic arthritis between January 1, 2015, and December 31, 2022, were retrospectively reviewed. Data regarding patient demographics, clinical presentation, microbiological cultures, treatment modalities, and outcomes were analyzed.

RESULTS

In a retrospective review of 52 cases of septic arthritis, a balanced gender distribution was observed (1:1 ratio), with the knee being the most commonly affected joint (80.8%). Methicillin-resistant Staphylococcus aureus predominated in native joints (24.2%), while Brucella spp. was more prevalent in prosthetic joints (21.1%). Joint preservation was achieved in most cases (84.6%), with no significant difference in clinical features between native and prosthetic joints. However, certain comorbidities were more common in native joint cases, including renal impairment (P = 0.002), hemodialysis (P = 0.004), heart disease (P = 0.013), and chronic liver disease (P = 0.048). At the same time, osteoarthritis was more prevalent in prosthetic joint cases (P = 0.013). Vancomycin was the most frequently used antibiotic (26.9%), and most patients received antibiotics before joint aspiration (57.7%). Surgical intervention, predominantly arthrotomy, was required in most cases (32.7%). Notably, a significant association was found between joint type and mortality (odds ratio = 0.587, P = 0.048), as well as the Charlson comorbidity index and mortality (P = 0.001).

CONCLUSION

This study highlighted distinctive microbiological profiles and etiological factors in septic arthritis cases in the Saudi Arabian population.

Outcomes of paediatric septic arthritis patients: rates of re-admission, re-operation, and unplanned emergency room visits after discharge

PURPOSE

This study is aimed at determining the rates and predictors of re-operation and re-admission in children with septic arthritis treated at an institution without routine clinical practice guidelines.

METHODS

This is a retrospective cohort study of patients less than 18 years old who underwent surgery for septic arthritis between January 1, 2009, and January 1, 2019, at a single tertiary-care paediatric institution. Uni- and multivariate analysis was performed to identify any risk factors associated with re-operation or unplanned visits to the emergency department after hospital admission compared to patients who had an uncomplicated post-operative course.

RESULTS

One hundred and forty-four patients were included. The mean age was five years (range 1 month-17 years), and the most commonly affected joint was the hip. The re-admission rate was 1% (n = 2), and the re-operation rate was 8% (n = 12). Twenty percent of patients (n = 29) had unplanned presentations to the emergency department (ED) after discharge. Discharge CRP level was not significantly higher in patients with unplanned presentations to the ED or re-operation. Positive joint fluid culture and infection of any other joint than the hip increased the likelihood of re-operation. Patients who had septic arthritis of the hip were more likely to have an unplanned ED presentation.

CONCLUSIONS

Rates of re-admission and re-operation were similar to literature despite lack of a standardized treatment pathway or discharge protocol. Outcomes of pediatric septic arthritis did not correlate with discharge CRP level. There was a high rate of unplanned ED visits after discharge.

Droplet digital PCR aids in the diagnosis of children with fever of unknown origin --A typical case report

Many clinical conditions can cause fever of unknown origin (FUO) in children, but the etiological diagnosis remains challenging despite the variety of inspection methods available at present. This study aims to investigate the effectiveness of droplet digital polymerase chain reaction (ddPCR) in identifying pathogens in children with FUO as a novel application. A 7-month-old boy failed to obtain etiology evidence for his disease through various tests. After collecting peripheral blood for ddPCR analysis, Staphylococcus aureus and Escherichia coli were detected, and Sanger sequencing confirmed the pathogens. During the disease, the child developed septic arthritis and osteomyelitis in the femur. Despite the patient's fever being removed, his limb activity improving, and inflammatory biomarkers decreasing, avascular necrosis of the femoral head remained after targeted antibiotic treatment and surgery. If the patient had undergone ddPCR analysis at an early stage, it may be possible to avoid sequelae. ddPCR helps identify pathogens in the diagnosis of children with FUO and could be a promising complementary tool.

Increased risk of osteomyelitis and septic arthritis in osteogenesis imperfecta

We investigated the prevalence of osteomyelitis and septic arthritis in individuals with osteogenesis imperfecta (OI) as compared to the general population. We performed a retrospective cohort study utilizing the TriNetX Analytics platform, a federated, aggregated electronic health record (EHR) research network containing national, deidentified EHR data. We queried patients with OI, based on encounter diagnoses. Patients in this group with any occurrence of osteomyelitis or septic arthritis were recorded. A control cohort was established to compare the prevalence in patients without OI. Of 8444 individuals with OI, 433 (5.13%) had encounter diagnoses for osteomyelitis and 61 (0.72%) had encounter diagnoses for septic arthritis. In comparison, of 79 176 436 patients without OI, 352 009 (0.44%) had encounter diagnoses for osteomyelitis, while 106 647 (0.13%) had encounter diagnoses for septic arthritis. The relative risk for osteomyelitis in OI patients was 11.53 (95% CI: 10.52-12.64), while the relative risk for septic arthritis was 5.36 (95% CI: 4.18-6.89). The relative risk for osteomyelitis in pediatric OI patients was 30.55 (95% CI: 24.35-38.28). To our knowledge, this is the first study investigating musculoskeletal infections in patients with OI, as well as the first to report the overall prevalence in the general population. Clinicians may benefit from a high index of suspicion for musculoskeletal infections in OI patients with corresponding symptoms. Further study is warranted to investigate if modifications to conventional diagnostic pathways and criteria are valuable in this population. Level of evidence: Retrospective Cohort Study - Level II.

Does rickets carry an increased risk of osteomyelitis and septic arthritis? An aggregated electronic health record data study

To investigate the prevalence of osteomyelitis and septic arthritis in pediatric patients with rickets, compared to the general population. A retrospective cohort study was conducted using the TriNetX analytics network, which aggregates deidentified electronic health record data from over 105 million US patients. We queried pediatric patients with rickets, based on ICD-10-CM (International Classification of Diseases, Tenth Revision, Clinical Modification) encounter diagnoses. Patients with any ICD-10-CM encounter diagnoses of osteomyelitis or septic arthritis were reported. We established a control cohort of pediatric patients without rickets. Of 7337 pediatric patients (≤18 years old) with a rickets diagnosis, 96 [1.31%, 95% confidence interval (CI): 1.05%-1.57%] had a diagnosis of osteomyelitis and 28 (0.38%, 95% CI: 0.24%-0.52%) had a diagnosis of septic arthritis. In comparison, of the 17 240 604 pediatric patients without a rickets diagnosis, 16 995 (0.10%, 95% CI: 0.10%-0.10%) had a diagnosis of osteomyelitis and 8521 (0.05%, 95% CI: 0.05%-0.05%) had a diagnosis of septic arthritis. The relative risk for an osteomyelitis diagnosis in pediatric patients with a rickets diagnosis was 13.27 (95% CI: 10.86-16.23), while the relative risk for a septic arthritis diagnosis was 7.72 (95% CI: 5.33-11.18). Pediatric patients with a diagnosis of rickets have over 10- and 5-times higher relative risks for having a diagnosis of osteomyelitis and septic arthritis, respectively, compared to those without a diagnosis of rickets. This is the first study to explore musculoskeletal infections in rickets patients, highlighting the importance of clinicians being vigilant about these conditions.

A devastating complication from neonate knee septic arthritis due to conservative treatment: A case report

INTRODUCTION

Septic arthritis in the neonate is a devastating condition that affects children and causes irreversible limb dysfunction or deformity. Neonatal septic arthritis is harmful and will end with skeletal abnormalities.

PRESENTATION OF CASE

Neonate born with ileal atresia and underwent surgical treatment. Postoperatively, the patient experienced sepsis and was accompanied by septic arthritis. The patient was given triple IV antibiotic treatment without surgical debridement. Ten months later the deformity became prominent with physeal destruction of the affected area at distal femur. At age six the patient came to the orthopaedic outpatient clinic and there was a 3 cm limb-length discrepancy of both legs.

DISCUSSION

Early diagnosis of septic arthritis is critical for successful treatment, since neonates with delayed proper diagnosis have been shown to have poor long-term prognosis. In our case the patient was only managed by IV antibiotics administration and continued with oral antibiotics. The reason for this decision due to general condition was improved after medication although clinically he still has a small amount of knee swelling.

CONCLUSION

Neonatal septic arthritis is dangerous and may have a devastating long term complication. Surgical management should be considered as treatment of choice if there is a lack or no progression from clinical and laboratory examination after antibiotic adiminstration. Growth arrest on the distal femur will result in leg length disparity and angular deformity.

[Septic arthritis and transient synovitis of the hip]

CLINICAL/METHODICAL ISSUE

Differentiating between septic arthritis and transient synovitis can be challenging but is very important as a late diagnosis of septic arthritis can lead to sepsis and joint damage. For correct diagnosis and prediction of complications, the right combination of physical examination, laboratory and radiological studies is needed.

STANDARD RADIOLOGICAL METHODS

Hip ultrasound is easy to learn and has a high sensitivity for joint effusion. Faster diagnosis and therapy are possible due to increasing use of ultrasound. Magnetic resonance imaging (MRI) is primarily used to rule out co-infections (osteomyelitis, pyomyositis) and differential diagnoses. X‑ray is typically nonremarkable in septic arthritis.

PRACTICAL RECOMMENDATIONS

Routine use of ultrasound in nontraumatic pediatric hip pain. Generous use of MRI in case of elevated inflammatory markers or inconclusive clinical findings. Using only few sequences may be appropriate to avoid sedation, primarily fluid sensitive sequences (fat-saturated T2, TIRM, STIR), in case of positive findings, accompanied by T1-weighted images.

Septic Arthritis of the Elbow in a Premature Neonate: An Uncommon Disease in an Uncommon Location

Septic arthritis (SA) is an infrequent diagnosis in the neonate. This case illustrates the presentation of SA within the elbow, an atypical location for neonatal SA. SA should be considered in any neonate with joint swelling, as symptoms are often subtle. Constitutional symptoms of infection, including fever, may not be present in the neonate. Staphylococcus aureus is the most common etiologic organism, and neonatal SA is often caused by hematogenous spread partially due to unique neonatal intraosseous anatomy. Joint aspiration can provide a definitive diagnosis and aid in targeted antimicrobial therapy. Other laboratory tests, including C-reactive protein and erythrocyte sedimentation rate, can aid in diagnosis. Ultrasound and magnetic resonance imaging can demonstrate joint effusion along with osteomyelitis, which is often seen concurrently with neonatal SA. There are no definitive guidelines for the treatment of neonatal SA. Conservative therapy with antimicrobials along with surgical intervention are the mainstays of treatment. Prompt diagnosis and treatment are crucial to decrease permanent joint damage. [Pediatr Ann. 2023;52(8):e292-e296.].

Pyogenic flexor tenosynovitis due to Kingella kingae in an infant

Pyogenic flexor tenosynovitis is relatively common but is seldom reported in young children. Kingella kingae is increasingly recognised as a causative agent. We report on an infant who presented with a palmar deep space infection and pyogenic flexor tenosynovitis caused by K. kingae K. kingae is a fastidious, often culture-negative, organism which has been increasingly recognised as a cause of paediatric orthopaedic infections, including flexor tenosynovitis. Clinical suspicion should be heightened, and antibiotic coverage broadened in the setting of a positive physical examination and negative blood cultures.

Neonatal Septic Arthritis of the Hip: A Case Report

Neonatal septic arthritis is a bacterial infection that, if not identified and treated right away, can affect human joints and result in osteonecrosis, joint destruction, and permanent abnormalities. Around 0.3 out of every 1,000 live births are impacted by septic arthritis worldwide. Although there is very little available data on the newborn population, we present a novel case of neonatal hip septic arthritis that was presented to our hospital and was successfully treated with surgical irrigation and debridement through arthrotomy with the Smith-Petersen approach in addition to antibiotics, despite its early vague presentation and lack of complications. Thus, it is crucial to clinically and radiologically evaluate neonates presenting with obscure symptoms and signs to prevent future disabilities and complications resulting from septic arthritis.

An update on recent progress of the epidemiology, etiology, diagnosis, and treatment of acute septic arthritis: a review

Acute septic arthritis is on the rise among all patients. Acute septic arthritis must be extensively assessed, identified, and treated to prevent fatal consequences. Antimicrobial therapy administered intravenously has long been considered the gold standard for treating acute osteoarticular infections. According to clinical research, parenteral antibiotics for a few days, followed by oral antibiotics, are safe and effective for treating infections without complications. This article focuses on bringing physicians up-to-date on the most recent findings and discussions about the epidemiology, etiology, diagnosis, and treatment of acute septic arthritis. In recent years, the emergence of antibiotic-resistant, particularly aggressive bacterial species has highlighted the need for more research to enhance treatment approaches and develop innovative diagnosis methods and drugs that might combat better in all patients. This article aims to furnish radiologists, orthopaedic surgeons, and other medical practitioners with contemporary insights on the subject matter and foster collaborative efforts to improve patient outcomes. This review represents the initial comprehensive update encompassing patients across all age groups.

Mitigating Lactate-Associated Immunosuppression against Intracellular Bacteria Using Thermoresponsive Nanoparticles for Septic Arthritis Therapy

Intracellular bacteria are the major contributor to the intractability of septic arthritis, which are sequestered in macrophages to undermine the innate immune response and avoid the antibacterial effect of antibiotics due to the obstruction of the cell membrane. Herein, we report a thermoresponsive nanoparticle, which consists of a phase-change material shell (fatty acids) and an oxygen-producing core (CaO₂-vancomycin). Under external thermal stimulation, the shell of the nanoparticle transforms from a solid phase to a liquid phase. Then the CaO₂-Vancomycin core is exposed to the surrounding aqueous solution to release vancomycin and generate Ca(OH)₂ and oxygen, thereby depleting accumulated lactate to mitigate lactate-associated immunosuppression, stabilizing hypoxia-inducible factor-1α (HIF-1α) to enhance M1-like polarization of macrophages, and increasing reactive oxygen species (ROS) and reactive nitrogen species (RNS) production. This combined effect between the controlled release of antibiotics and enhancement of host innate immunity provides a promising strategy to combat intracellular bacteria for septic arthritis therapy.

Seasonal Variation of Pediatric Septic Arthritis in the United States: A PHIS Database Study

BACKGROUND

The presence of seasonal patterns in pediatric septic arthritis cases is a common orthopaedic teaching. Seasonal variation has been seen in centers outside of the United States and with other inflammatory and infectious joint-related conditions within the country, but it is unknown if a seasonal pattern exists among different regions of the United States. The purpose of this study was to examine the seasonal variation of septic arthritis within specific regions across the United States.

METHODS

The Pediatric Health Information System database was queried for all patients 19 years or younger who were treated for septic arthritis. Data from 34 pediatric hospitals in the Pediatric Health Information System initiative were included. Centers were organized by geographical region, and season of presentation was determined using equinoxes/solstices. χ 2 tests were performed to detect seasonal differences in septic arthritis for the entire cohort and separated by geographical region. Proportion differences along with 95% CIs were provided.

RESULTS

Between 2016 and 2019, there were 5764 cases of septic arthritis. Median age at diagnosis was 6.2 years (range: 0 to 19.0 y). Each season contributed 24% to 25% of the total septic arthritis cases, and there were no significant differences detected between the 4 seasons ( P =0.66). There was no seasonal variation seen in the Midwest, South, or West ( P =0.71, 0.98, 0.36, respectively). However, there was seasonal variation in the Northeast ( P =0.05), with fall and summer having a higher percentage of cases (28%) than the winter (21%).

CONCLUSIONS

This study showed no clear seasonal variation in septic arthritis in children across the United States using a national database of pediatric hospital centers. However, there is regional seasonal variation in the Northeast, which may relate to climate differences. With no clear seasonal variation across the United States, continued diligence is needed in diagnosing septic arthritis throughout the year.

LEVEL OF EVIDENCE

Prognostic II.

Case report: Acinetobacter baumannii septic arthritis in an immunocompetent infant

Acinetobacter baumannii is a gram-negative coccobacilli, mainly causing nosocomial infections with poor prognosis, especially in patients with prolonged hospitalization or antibiotics administration. A. baumannii pneumonia is the most common clinical form and usually occurs in critically ill patients in the intensive care unit. However, septic arthritis caused by A. baumannii is rarely reported. In this report, we describe a case of A. baumannii septic arthritis combined with incomplete Kawasaki disease in an infant. The child's chief complaint was a 2-week intermittent fever with poor response to antibiotics. Initial physical examination revealed swollen lymph nodes in the neck, pharynx congestion, and the appearance of rashes. Combined with laboratory tests, the diagnosis of incomplete Kawasaki disease was considered. After administration of high-dose intravenous immunoglobulin and corticosteroids, the child's fever improved and periungual desquamation appeared simultaneously. Swelling of the right knee occurred 5 days after the fever improved and imaging tests of MRI and ultrasound suggested the existence of infection. A diagnosis of septic arthritis was established subsequently, and arthroscopy was carried out. A. baumannii was finally identified by metagenomics next-generation sequencing of joint draining fluid for pathogenic microorganisms. Treatment with meropenem was then started. The patient eventually recovered and was discharged from the hospital after 23 days of treatment with meropenem. Although A. baumannii is not a common bacterium of septic arthritis, this rare infection can still occur in infants. Early diagnosis, pathogenic identification, and target antibiotic treatment are important to reduce the occurrence of joint sequelae.

Pediatric Emergency MRI

There is an overall increase in the use of imaging in the pediatric emergency room setting, which is accompanied by a reduction in computed tomography examinations performed mainly due to the increased awareness of the risks of ionizing radiation. Advances in MRI technology have led to shortened scan time, decreased motion sensitivity, and improved spatial resolution. With increased access to MRI in the emergency room setting, the goal of this article is to review major applications of MR in pediatric emergency room patients.

Is Early Surgical Intervention Necessary for Acute Neonatal Humeral Epiphyseal Osteomyelitis: A Retrospective Study of 31 Patients

Objective: To review the treatment experience of neonatal humeral epiphyseal osteomyelitis retrospectively. Study design: Retrospective cohort study of infants with neonatal humeral epiphyseal osteomyelitis. Patients were divided into conservative group and surgical group, and the surgical group was subdivided into early and delayed surgical group. Results: In total, there were 7 patients in the conservative group and 24 in the surgical group. The length of hospital stay and intravenous course of antibiotic therapy were both significantly shorter in the surgical group (p < 0.001). The full recovery rate was also higher in the surgical group (83.3%) than the conservative group (14.3%) (p < 0.001). Early surgery group (n = 14) had an insignificantly higher positive rate of pus/aspirate culture and full recovery rate than delayed surgery group (n = 10). Conclusion: Surgical treatment for neonatal humeral epiphyseal osteomyelitis demonstrated significantly higher rates of positive culture for the pathogen, a shorter course of intravenous oral antibiotics, and lower incidence of growth abnormality than conservative treatment. In our institution, most of culture outcome Gram-positive bacteria, and early surgical treatment was recommended with better outcome than delayed surgical group. Empirical antibiotics should be tailored to the epidemiological characteristics of local virulent bacteria.

Hospital care and medical costs of septic arthritis in Spain: a retrospective multicenter analysis

OBJECTIVES

This study aimed to review the characteristics of patients admitted with septic arthritis in Spanish hospitals and to measure the associated direct medical costs.

METHODS

Hospital admission records of patients with septic arthritis as a primary diagnosis registered between 2010 and 2019 were evaluated in a retrospective study. Admission cost in the database is based on the diagnosis-related group-based hospital payment systems, determined by the Spanish Ministry of Health.

RESULTS

Files from 16,438 patients were evaluated; median age was 56 years and 62.8% of patients were males. Staphylococcus was the most frequently registered pathogen, and 2.7% of admissions registered an antibiotic-resistant infection. Median hospitalization time was 14 days for adult patients and 8 days for children, with an in-hospital mortality rate of 3.7% for adult patients, and no deaths registered in children. The median length of intensive care unit (ICU) stay was 3 days. The mean admission cost was €6,382 per patient, with no significant differences between age groups. Admission costs increased significantly with the length of hospital stay. The total medical cost reached 12.7 million euros per year, considering all patients in the database.

CONCLUSIONS

This study provides new data on the medical costs of septic arthritis in Spain, providing a basis for the revision of resource allocation decisions in order to reduce the burden of this condition at the healthcare system level. Further research will be required to quantify the total burden associated with this condition.