Childhood osteomyelitis: imaging characteristics

[Imaging Findings in Pediatric Musculoskeletal Infection and Inflammation]

Infections and inflammatory conditions of immature musculoskeletal systems in pediatric patients also affect the adjacent muscles, connective tissues, and joints. Rapid diagnosis leading to appropriate treatment can significantly impact the occurrence of complications and mortality rates due to these conditions. When a radiologist becomes familiar with the imaging findings of pediatric musculoskeletal infections and inflammatory diseases, rapid differential diagnoses and more timely and appropirate treatment could be possible. In this paper, we introduce the imaging findings of infectious and inflammatory diseases affecting the immature musculoskeletal system, such as osteomyelitis, pyogenic arthritis, juvenile idiopathic arthritis, and hemophilic arthritis, based on the anatomical and pathophysiological characteristics of the immature musculoskeletal system in children.

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.

Multifocal osteomyelitis in a child with sickle cell disease and review of the literature regarding best diagnostic approach

Key Clinical Message

In patients with sickle cell disease, we must be more cognizant of the possibility of multifocal osteomyelitis. Diagnosis can be challenging in this patient population as the symptoms mimic vaso-occlusive crisis. There is no gold standard in imaging.

Abstract

Osteomyelitis occurs more frequently in children with sickle cell disease. Diagnosis is challenging as it mimics vaso-occlusive crises, a common manifestation of sickle cell disease. We present a case of a 22-month-old girl with sickle cell disease and multifocal osteomyelitis. We review the literature on the utility of diagnostic imaging.

Acute musculoskeletal infection in children: assessment and management

Musculoskeletal infection in children is challenging to treat, and includes septic arthritis, deep tissue infection, osteomyelitis, discitis and pyomyositis. Delays to diagnosis and management, and under-treatment can be life-threatening and result in chronic disability. The British Orthopaedic Association Standards for Trauma include critical steps in the timely diagnosis and management of acute musculoskeletal infection in children, the principles of acute clinical care and the service delivery requirements to appropriately manage this cohort of patients. Orthopaedic and paediatric services are likely to encounter cases of acute musculoskeletal infection in children and thus an awareness and thorough understanding of the British Orthopaedic Association Standards for Trauma guidelines is essential. This article reviews these guidelines and associated published evidence for the management of children with acute musculoskeletal infection.

Magnitude of chronic osteomyelitis and its associated factors in children as diagnosed on X-ray visiting at Felege Hiwot Comprehensive Specialized Hospital, Northwest Ethiopia: A cross-sectional study

Objectives

To assess the magnitude of chronic osteomyelitis and its associated factors in children at Felege Hiwot Comprehensive Specialized Hospital, Bahir Dar, Ethiopia, in 2022.

Methods

A hospital-based cross-sectional study was done between April 15, 2022 and August 15, 2022, in children with an age of 18 years or below, who visited Felege Hiwot Comprehensive Specialized Hospital. A total sample size of 168 participants was involved in the study. The random sampling technique was applied to select the study participants. The data were collected from the patients, their charts, and X-ray requests. The data were cleaned, stored, checked for completeness, and entered into EpiData Version 3.1, which were then exported to SPSS Version 23 for analysis. Descriptive analysis was done, and bivariable and multivariable logistic regression were used for analysis.

Results

The prevalence of chronic osteomyelitis was found to be 86.3%. The tibia and femur were the most commonly involved bones, and metaphyseal involvement was very common. The most common radiological findings were sequestrum (56%) and involucrum (53%). Of the total patients with radiological evidence of chronic osteomyelitis, 16.6% had complications, the most common of which was a pathologic fracture (12.4%). Being male (adjusted odds ratio = 6.162, 95% confidence interval: 1.12-34.147), being over 10 years old (adjusted odds ratio = 4.048, 95% confidence interval: 1.032-15.886), living in a rural area (adjusted odds ratio = 4.046, 95% confidence interval: 1.236-13.364), having a discharging sinus (adjusted odds ratio = 5.237, 95% confidence interval: 1.393-19.693), having a clinical complaint lasting more than 1 year (adjusted odds ratio = 5.189, 95% confidence interval: 1.247-21.588), and a preceding event of trauma (adjusted odds ratio = =10.363, 95% confidence interval: 1.101-97.509) were the factors associated with chronic osteomyelitis.

Conclusion

The prevalence of chronic osteomyelitis is high. In this study, being male, being in the age group above 10 years, having rural residency, having a discharging sinus, having a clinical complaint duration of more than 1 year, and having a preceding event of trauma were the factors associated with chronic osteomyelitis. Therefore, healthcare providers should have a high index of suspicion of chronic osteomyelitis in older male children from rural areas with a chronic discharging sinus following trauma.

Unusual ultrasound diagnosis of hair implantation osteomyelitis of the thumb

Osteomyelitis is a challenging condition to diagnose and successfully treat. A clinician diagnosing osteomyelitis is reliant on relevant aspects of clinical history, inflammatory markers and radiological imaging such as X-rays, CT and contrast MRI. The confirmation of the presurgical diagnosis is made from microbiological analysis of the bone biopsy and/or histological analysis for features of inflammatory changes. An ultrasound scan is generally thought to have less value in osteomyelitis diagnosis due to its inability to interrogate bone. However, this investigation can be helpful in detecting the site and size of soft tissue collections secondary to osteomyelitis and the presence of any associated foreign bodies. We present a case where an ultrasound scan played a key role in supporting the diagnosis of osteomyelitis of the thumb in a dog groomer. This is the first reported case of hair implantation osteomyelitis presenting without a cutaneous sinus.

The Utility of Routine Radiographic Monitoring in Pediatric Osteoarticular Infections

BACKGROUND

Pediatric musculoskeletal (MSK) infections broadly include isolated osteomyelitis (OM), septic arthritis (SA), and combined infections (OM+SA). These diagnoses are often monitored with serum inflammatory markers and serial radiographs to monitor treatment response and development of negative sequelae, despite limited data supporting these practices. The purpose of this study is to evaluate the utility of obtaining serial radiographic follow-up for pediatric osteoarticular infections.

METHODS

An institutional review board-approved retrospective review was completed. Children 18 years and below admitted to a single institution with a culture/biopsy-proven diagnosis of OM, SA, or OM+SA. All postdischarge radiographs were reviewed and retrospectively categorized as either routine (scheduled) or reactive. Routine radiographs were obtained regardless of clinical presentation. Reactive radiographs were obtained in patients presenting with the sign of an altered clinical course. Negative sequelae, defined as growth arrest/disturbance, pathologic fracture, recurrent MSK infection, and underlying neoplastic process, were recorded and tracked. Descriptive statistics were used to summarize demographic and outcome variables. Number needed to screen (NNS) was defined as the inverse of the incidence of negative sequelae detected.

RESULTS

A total of 131 patients were included for analysis, with a mean age of 11.9 years (SD: 4.96 y). Ninety (69%) patients were diagnosed and treated for OM, 25 (19%) for SA, and 16 (12%) for combined infections. A total of 329 radiographs were obtained following discharge. Of those obtained, 287 (88%) were routine, resulting in the detection of 2 (0.7%) negative sequelae and a resultant NNS of 143 radiographs (95% confidence interval: 36-573). The remaining 39 were reactive radiographs, resulting in the detection of 2 (5.1%) negative sequelae with an NNS of 20 radiographs (95% confidence interval: 5-78).

CONCLUSIONS

While radiographs remain a widely utilized tool to screen for the development of negative sequelae in pediatric osteoarticular infections, they rarely alter management in the absence of other concerning clinical signs or symptoms such as recurrent fevers, swelling of the extremity, or limb deformity. Moreover, routine radiographic surveillance should be replaced with a reactive radiographic protocol.

LEVEL OF EVIDENCE

Level III-retrospective comparative study.

Discriminative Accuracy of Procalcitonin and Traditional Biomarkers in Pediatric Acute Musculoskeletal Infection

OBJECTIVES

Septic arthritis (SA) is responsible for 20% of pediatric musculoskeletal infections (MSKI) and can have significant consequences. Early detection of SA is critical, and procalcitonin (PCT) has emerged as a promising biomarker. This study assessed the test performance of PCT and traditional biomarkers for suspected SA.

METHODS

We conducted a prospective study at two pediatric emergency departments (ED). Data collected measured serum levels of C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), white blood cell (WBC) count, and PCT. Box and whisker plots were generated to compare the of the biomarkers by positive MSKI or a non-MSKI diagnosis. The diagnostic performance of biomarkers was examined using the area under the receiver operating characteristic curve (AUC), and optimal cut -points were identified using the Liu method.

RESULTS

Procalcitonin performed reasonably well for detection of MSKI (AUC, 0.72; confidence interval [95% CI], 0.59-0.84). However, CRP and ESR performed better (AUC, 0.88 and 0.78, respectively). White blood cell count was not predictive of MSKI. Patients with a PCT value >0.1 ng/mL, ESR values >19.5 mm/h, and a temperature higher than 99.0°F were more than twice as likely to have acute MSKI. A high CRP level was most predictive of acute MSKI, and patients with levels >2.38 mg/dL were 3.5 times more likely to have acute MSKI.

CONCLUSIONS

Procalcitonin is a potential biomarker for the clinical differential of MSKI in the pediatric ED. Additional research is warranted to establish the optimal diagnostic level for PCT, to increase sample size, and to examine any impact on cost.

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.

Imaging tests for the detection of osteomyelitis: a systematic review

BACKGROUND

Osteomyelitis is an infection of the bone. Medical imaging tests, such as radiography, ultrasound, magnetic resonance imaging (MRI), single-photon emission computed tomography (SPECT) and positron emission tomography (PET), are often used to diagnose osteomyelitis.

OBJECTIVES

To systematically review the evidence on the diagnostic accuracy, inter-rater reliability and implementation of imaging tests to diagnose osteomyelitis.

DATA SOURCES

We conducted a systematic review of imaging tests to diagnose osteomyelitis. We searched MEDLINE and other databases from inception to July 2018.

REVIEW METHODS

Risk of bias was assessed with QUADAS-2 [quality assessment of diagnostic accuracy studies (version 2)]. Diagnostic accuracy was assessed using bivariate regression models. Imaging tests were compared. Subgroup analyses were performed based on the location and nature of the suspected osteomyelitis. Studies of children, inter-rater reliability and implementation outcomes were synthesised narratively.

RESULTS

Eighty-one studies were included (diagnostic accuracy: 77 studies; inter-rater reliability: 11 studies; implementation: one study; some studies were included in two reviews). One-quarter of diagnostic accuracy studies were rated as being at a high risk of bias. In adults, MRI had high diagnostic accuracy [95.6% sensitivity, 95% confidence interval (CI) 92.4% to 97.5%; 80.7% specificity, 95% CI 70.8% to 87.8%]. PET also had high accuracy (85.1% sensitivity, 95% CI 71.5% to 92.9%; 92.8% specificity, 95% CI 83.0% to 97.1%), as did SPECT (95.1% sensitivity, 95% CI 87.8% to 98.1%; 82.0% specificity, 95% CI 61.5% to 92.8%). There was similar diagnostic performance with MRI, PET and SPECT. Scintigraphy (83.6% sensitivity, 95% CI 71.8% to 91.1%; 70.6% specificity, 57.7% to 80.8%), computed tomography (69.7% sensitivity, 95% CI 40.1% to 88.7%; 90.2% specificity, 95% CI 57.6% to 98.4%) and radiography (70.4% sensitivity, 95% CI 61.6% to 77.8%; 81.5% specificity, 95% CI 69.6% to 89.5%) all had generally inferior diagnostic accuracy. Technetium-99m hexamethylpropyleneamine oxime white blood cell scintigraphy (87.3% sensitivity, 95% CI 75.1% to 94.0%; 94.7% specificity, 95% CI 84.9% to 98.3%) had higher diagnostic accuracy, similar to that of PET or MRI. There was no evidence that diagnostic accuracy varied by scan location or cause of osteomyelitis, although data on many scan locations were limited. Diagnostic accuracy in diabetic foot patients was similar to the overall results. Only three studies in children were identified; results were too limited to draw any conclusions. Eleven studies evaluated inter-rater reliability. MRI had acceptable inter-rater reliability. We found only one study on test implementation and no evidence on patient preferences or cost-effectiveness of imaging tests for osteomyelitis.

LIMITATIONS

Most studies included < 50 participants and were poorly reported. There was limited evidence for children, ultrasonography and on clinical factors other than diagnostic accuracy.

CONCLUSIONS

Osteomyelitis is reliably diagnosed by MRI, PET and SPECT. No clear reason to prefer one test over the other in terms of diagnostic accuracy was identified. The wider availability of MRI machines, and the fact that MRI does not expose patients to harmful ionising radiation, may mean that MRI is preferable in most cases. Diagnostic accuracy does not appear to vary with the potential cause of osteomyelitis or with the body part scanned. Considerable uncertainty remains over the diagnostic accuracy of imaging tests in children. Studies of diagnostic accuracy in children, particularly using MRI and ultrasound, are needed.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42017068511.

FUNDING

This project was funded by the National Institute for Health Research Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 23, No. 61. See the NIHR Journals Library website for further project information.

Mesonephric Remnant (Paroophoron) Presenting as a Congenital Lumbar Sinus in a Child

Presence of symptomatic mesonephric duct remnants is rare in pediatric age group. These can be present in dormant physiological or symptomatic pathological states. Pathologies can vary from benign cysts to malignant tumors. We here report a rare presentation in a 2-year-old female, of a mesonephric remnant in the form of a sinus above the iliac crest.

Imaging mimics of chronic recurrent multifocal osteomyelitis: avoiding pitfalls in a diagnosis of exclusion

Chronic recurrent multifocal osteomyelitis (CRMO) is a pediatric autoinflammatory disorder that is characterized by multiple sterile inflammatory bone lesions with a relapsing and remitting course. CRMO belongs to the autoinflammatory family of rheumatologic disorders based on absence of significant titers of autoantibodies and autoreactive T-lymphocytes. In absence of pathognomonic clinical, radiographic or pathological features, diagnosis can be challenging. CRMO shares imaging features with other diseases. It is important for radiologists to be able to differentiate other diseases from CRMO because prognosis varies from completely benign to frankly malignant. In this article we first present the clinical and imaging features of CRMO to help readers gain an understanding of the disease process, then discuss our imaging approach to CRMO and review other disease processes that sometimes share similar imaging findings to CRMO and review differentiating features to help avoid misdiagnoses.

Point-of-Care Ultrasound in a Child with Chest Wall Pain and Rib Osteomyelitis

BACKGROUND

Diagnosis of acute osteomyelitis in young children can be challenging due to the lack of specific clinical signs and symptoms. Prompt diagnosis and treatment is essential to prevent complications and to improve long-term prognosis and reduce the need for operative intervention. Point-of-care ultrasound (POCUS) may be a useful tool to detect early changes associated with osteomyelitis.

CASE REPORT

A 26-month-old boy presented with 6 days of fever and 3 days of focal pain over the right anterior lower ribs without swelling, erythema, or bony deformity, and negative chest x-ray study. A POCUS was performed by the ultrasound fellows and revealed deep soft tissue swelling, periosteal elevation, and increased vascular flow with color Doppler. The patient was admitted to the pediatric service with infectious disease consultation and started on antibiotics. Magnetic resonance imaging confirmed the diagnosis of a right seventh anterior rib osteomyelitis, and the patient subsequently improved and was discharged home. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: In this case, the use of POCUS in the emergency department heightened the suspicion for acute osteomyelitis in a rare location and guided early diagnosis and treatment.

Effects of Different Volatile Anesthetics on Cytokine and Chemokine Production After Ischemia-Reperfusion Injury in Patients Undergoing Living-Donor Kidney Transplant

OBJECTIVES

Renal transplant is the treatment of choice for patients with end-stage renal disease. Ischemiareperfusion damage is a major cause of early renal dysfunction during the perioperative period. Ischemic hypoxic damage increases local inflammation, leading to secretion of cytokines and chemokines. Anesthetic conditioning is a widely described strategy to attenuate ischemia-reperfusion injury. Here, we compared the effects of desflurane and sevoflurane on serum proinflammatory cytokines and urine chemokines in living-donor kidney transplant recipients.

MATERIALS AND METHODS

Eighty donor-recipient couples were included in this randomized study. Anesthesia maintenance was provided by desflurane or sevoflurane. Patient demographic characteristics, immunologic data, clinical data, and hemodynamic parameters were recorded. Tumor necrosis factor α, interleukins 2 and 8, chemokines 9 and 10, and serum creatinine levels were studied from pretransplant, posttransplant days 1 and 7, and posttransplant months 1 and 3 sample results. Estimated glomerular filtration rates were calculated. Acute rejection episodes and graft loss within 6 months posttransplant were recorded.

RESULTS

Seventy donor-recipient couples completed the study. There were no significant differences in demographic, immunologic, and clinical data between desflurane and sevoflurane groups (P > .05). Tumor necrosis factor α, interleukin 2, chemokine 9, and chemokine 10 levels were similar preoperatively and on postoperative days 1 and 7 and months 1 and 3 (P > .05). Serum interleukin 8 levels were significantly higher in patients who received sevoflurane on postoperative days 1 (P = .045) and 7 (P = .037). No significant differences were detected in serum creatinine and estimated glomerular filtration rate between groups (P > .05). No graft loss occurred within 6 months posttransplant.

CONCLUSIONS

Although sevoflurane seemed to produce higher interleukin 8 levels posttransplant, both desflurane and sevoflurane had similar effects on posttransplant kidney function. We suggest that both agents have protective effects on ischemic-reperfusion damage in living-donor kidney transplant recipients.

An untapped potential for imaging of peripheral osteomyelitis in paediatrics using [18F]FDG PET/CT -the inference from a juvenile porcine model

PURPOSE

To examine parameters affecting the detection of osteomyelitis (OM) by [18F]FDG PET/CT and to reduce tracer activity in a pig model.

BACKGROUND

[18F]FDG PET/CT is recommended for the diagnosis of OM in the axial skeleton of adults. In children, OM has a tendency to become chronic or recurrent, especially in low-income countries. Early diagnosis and initiation of therapy are therefore essential. We have previously demonstrated that [18F]FDG PET/CT is promising in juvenile Staphylococcus aureus (S. aureus) OM of peripheral bones in a pig model, not failing even small lesions. When using imaging in children, radiation exposure should be balanced against fast diagnostics in the individual case.

METHODS

Twenty juvenile pigs were inoculated with S. aureus. One week after inoculation, the pigs were [18F]FDG PET/CT scanned. PET list-mode acquired data of a subgroup were retrospectively processed in order to simulate and examine the image quality obtainable with an injected activity of 132 MBq, 44 MBq, 13.2 MBq, and 4.4 MBq, respectively.

RESULTS

All lesions were detected by [18F]FDG PET and CT. Some lesions were very small (0.01 cm3), and others were larger (4.18 cm3). SUVmax was higher when sequesters (p = 0.023) and fistulas were formed (p < 0.0001). The simulated data demonstrated that it was possible to reduce the activity to 4.4 MBq without compromising image quality in pigs.

CONCLUSIONS

[18F]FDG PET/CT localized even small OM lesions in peripheral bones. It was possible to reduce the injected activity considerably without compromising image quality, impacting the applicability of PET/CT in peripheral OM in children.

Chronic Osteomyelitis after Seven Years Neglected Bone Exposed in 12-Year-Old Boy: A Case Report

BACKGROUND:

Access to modern medicine is still limited in some rural areas in Indonesia. This is mostly due to lack of people’s knowledge and concern for their health, especially in orthopaedic cases. Osteomyelitis is generally described as infection and inflammation of the bone, which results in local bone destruction, necrosis, and apposition of new bone. Chronic post-traumatic osteomyelitis (CPTO) is a complex condition and one of the most challenging problems in orthopaedic surgery that cause considerable morbidity.

CASE PRESENTATION:

We present a case of chronic post-traumatic osteomyelitis with radial nerve injury, in which radical surgical debridement and broad-spectrum antibiotic administration were done. A 12-year-old boy with a history of falling from the three-meter-high tree had swollen, deformed, and neglected humerus bone exposed. After stabilisation in the emergency room, surgical limb amputation was scheduled, yet the family refused this medical care and chose debridement instead.

CONCLUSION:

This case is an important addition to the literature about chronic post-traumatic osteomyelitis with neglected bone exposed and the lacking of society’s concern in regards to orthopaedic cases.

Imaging of the limping child

Limping is a challenging symptom in the pediatric patient as the diagnosis can range from traumatic, malformative, infectious/inflammatory and neoplastic diseases. In this paper, we propose a schematic imaging algorithm to the limping child in three different age groups (Toddler: 1-3years, child: 4-10 years; adolescent: 11-16 years) based on presence of signs of infection, any specific localization of pain, and history of trauma. In this setting, the most common imaging pitfalls are also summarised. Finally, a literature review of the main differential causes of limping in the pediatric patient is reported.

Pediatric Musculoskeletal Imaging: The Indications for and Applications of PET/Computed Tomography

The use of PET/computed tomography (CT) for the evaluation and management of children, adolescents, and young adults continues to expand. The principal tracer used is 18F-fluorodeoxyglucose and the principal indication is oncology, particularly musculoskeletal neoplasms. The purpose of this article is to review the common applications of PET/CT for imaging of musculoskeletal issues in pediatrics and to introduce the use of PET/CT for nononcologic issues, such as infectious/inflammatory disorders, and review the use of 18F-sodium fluoride in trauma and sports-related injuries.

Radionuclide Imaging of Infection and Inflammation in Children: a Review

With the exception of radiolabeled monoclonal antibodies, antibody fragments and radiolabeled peptides which have seen little application in the pediatric population, the nuclear medicine imaging procedures used in the evaluation of infection and inflammation are the same for both adults and children. These procedures include (1) either a two- or a three-phase bone scan using technetium-99m methylene diphosphonate; (2) Gallium 67-citrate; (3) in vitro radiolabeled white blood cell imaging (using ¹¹¹Indium-oxine or ^99mTechnetium hexamethyl-propylene-amine-oxime-labeled white blood cells); and (4) hybrid imaging with ¹⁸F-FDG. But children are not just small adults. Not only are the disease processes encountered in children different from those in adults, but there are developmental variants that can mimic, but should not be confused with, pathology. This article discusses some of the differences between adults and children with osteomyelitis, illustrates several of the common developmental variants that can mimic disease, and, finally, focuses on the increasing use of ¹⁸F-FDG PET/CT in the diagnosis and response monitoring of children with infectious and inflammatory processes. The value of and need for pediatric specific imaging protocols are reviewed.

JOURNAL CLUB: Can Coronal STIR Be Used as Screening for Acute Nontraumatic Hip Pain in Children?

OBJECTIVE

The objective of this study is to evaluate whether coronal STIR MRI can be used as a screening test for nontraumatic acute hip pain in children.

MATERIALS AND METHODS

From 2008 to 2012, we identified all patients younger than 18 years at our tertiary care facility who underwent pelvic MRI including coronal STIR for the following indications: acute hip pain, limping, or refusal to bear weight. Patients with a history of trauma were excluded. Each MR image was independently reviewed by four radiologists who were blinded to the clinical outcome. After first reviewing the coronal STIR images only, they then reviewed the full MRI studies in a random order different from that used for review of the coronal STIR images. The sensitivity and specificity of STIR-only images in identifying the presence of abnormality and specific diagnoses were calculated, with the full MRI study considered as the reference standard. Kappa values were calculated for STIR-only and full MRI studies.

RESULTS

A total of 127 patients (67 female patients and 60 male patients; median age, 9 years; range, 5 months to 17 years) were identified. The most common abnormalities (calculated as the mean of frequency values noted by four readers) were hip effusion (52%; range, 46-58%), osteomyelitis (42%; range, 29-48%), and myositis (32%; range, 20-40%). For the detection of any abnormality, STIR-only images had a mean sensitivity of 95% and a mean specificity of 67%. For approximately one-third of STIR-only studies with true-positive results, additional abnormalities were found on full MRI studies.

CONCLUSION

Coronal STIR imaging of the pelvis has high sensitivity (95%) in the detection of abnormalities associated with acute nontraumatic hip pain in children, but it often misses additional abnormalities.

The Many Faces of Osteomyelitis: A Pictorial Review

The purpose of this pictorial review is to present an overview of the radioclinical features of osteomyelitis.

The presentation of the disease may vary depending on the clinical stage (acute, subacute and chronic), the pathogenesis of the infection and the age of the patient. Thorough knowledge of the basic pathophysiological mechanisms is a prerequisite to understanding the variable imaging appearance of osteomyelitis.

Special subtypes of osteomyelitis including CRMO and SAPHO will be discussed very shortly.

Paediatric bone and joint infection

Despite advances in understanding and management, paediatric osteoarticular infections continue to pose diagnostic difficulties for clinicians. Delays in diagnosis can lead to potentially devastating morbidity.No single investigation, including joint aspiration, is sufficiently reliable to diagnose conclusively paediatric bone and joint infection. Diagnosis should be based on a combination of clinical signs, imaging and laboratory investigations. Algorithms should supplement, and not replace, clinical decision making in all cases.The roles of aspiration, arthrotomy and arthroscopy in the treatment of septic arthritis are not clearly defined. There is a very limited role for surgery in the management of acute haematogenous osteomyelitis.The ideal duration and mode of administration of antibiotic therapy for osteoarticular paediatric infection is not yet fully defined but there is increasing evidence that shorter courses (three weeks) and early conversion (day four) to oral administration is safe and effective in appropriate cases. Clear and concise antibiotic guidelines should be available based on local population characteristics, pathogens and their sensitivities.Kingella kingae is increasingly identified through polymerase chain reaction and is now recognised as the commonest pathogen in children aged under four years. Methicillin-resistant Staphylococcus aureus and Panton-Valentine leukocidin-producing strains of Staph. aureus are being increasingly reported.A multidisciplinary integrated evidence-based approach is required to optimise outcomes.Further large-scale, multicentre studies are needed to delineate the optimal management of paediatric osteoarticular infection. Cite this article: EFORT Open Rev 2017;1:7-12. DOI: 10.1302/2058-5241.2.160027.

A Rare Case of Clavicle Osteomyelitis in a Child and Literature Review

Acute clavicle osteomyelitis in children is rare representing <3% of osteomyelitis cases. We treated a 12-year-old boy who presented with acute pain in the right clavicle and high fever for 4 days. MRI showed abnormal signal in the right clavicle with periosteal reaction. Staphylococcus aureus isolated from blood was susceptible to methicillin, clindamycin, and macrolides. Clindamycin was given intravenously for 3 wks and orally for another 3 wks with no recurrence. We reviewed clavicle osteomyelitis cases in children searching PubMed English literature. From a total of 89 studies retrieved, only 6 fulfilled the criteria and were analyzed. Sixteen patients (56% female) were included with a median age of 9 yrs (range 2 wks–16 yrs). Osteomyelitis was hematogenous in most cases, with S. aureus being the most frequent cause, isolated from either blood or tissue. Symptoms included fever, swelling, and localized bone tenderness. Antimicrobial therapy lasted for 4–12 weeks (median 7.5). Three patients required drainage or curettage. Recurrence occurred in 1/16 cases (6.2%) and persistence of symptoms occurred to 2/16 cases (12.5%) reported before 90s with unknown antimicrobial susceptibility of the pathogen. Acute clavicle osteomyelitis mainly affects older children and has generally good prognosis. Staphylococcus aureus is most commonly implicated and surgery may be needed.

[Treatment and progression of acute communautary osteoarticular infections in healthy children: A retrospective monocentric study of 64 patients]

INTRODUCTION

The prognosis of osteoarticular infections has improved over the past 20 years but it still remains potentially severe. The treatment of these infections has been simplified and shortened. In 2008, the Pediatric Infectious Disease Group (GPIP) established new therapeutic guidelines in order to standardize treatment in France. The aim of this study is to analyze practices in a Parisian hospital and assess the efficacy of this treatment in short and medium terms.

MATERIALS AND METHODS

This retrospective study focused on patients older than 3 months, without comorbidities, who were hospitalized for an acute osteoarticular infection in 2012 at Trousseau Hospital (Paris), with a follow-up of at least 4 weeks. The patients were selected from the hospital register.

RESULTS

The study included 64 patients of 156, who were admitted for examination with a diagnosis of acute osteoarticular infection, bacteriologically confirmed (29/64) or presumed on the basis of bacteriological evidence (35/64). The median age of the patients was 22 months. Of the patients, 78 % were febrile; 35 patients had arthritis (54.7 %), 21 osteomyelitis (32.8 %), seven osteoarthritis (10.9 %), and one spondylitis. Preferential localizations were the knees and hips; 61 % of arthritis cases were diagnosed with ultrasound, 54 % of osteomyelitis cases with scintigraphy. The two main microorganisms found were Kingella kingae (62.1 %) and Staphylococcus aureus (24.1 %). In 98 % of cases, patients were treated by cefamandole, with or without gentamicine, for a median duration of 3 days (1-10) intravenously, with oral relay by amoxicillin-clavulanic acid, for a total duration of 6 weeks, but in association with rifampicin in 40 % of cases without explanation. The median follow-up was 13 weeks, with a treatment success rate of 86 %.

CONCLUSION

The study of local practices showed us that the GPIP guidelines are not followed, with the duration of oral treatment being too long. The trend in therapy is toward short treatments of 10-20 days, with a shorter intravenous phase.

Pediatric Emergency Magnetic Resonance Imaging: Current Indications, Techniques, and Clinical Applications

MR imaging plays an important role in the detection and characterization of several pediatric disease entities that can occur in the emergent setting because of its cross-sectional imaging capability, lack of ionizing radiation exposure, and superior soft tissue contrast. In the age of as low as reasonably achievable, these advantages have made MR imaging an increasingly preferred modality for diagnostic evaluations even in time-sensitive settings. In this article, the authors discuss the current indications, techniques, and clinical applications of MR imaging in the evaluation of pediatric emergencies.

Vertebral Osteomyelitis and Septic Arthritis Associated With Staphylococcus hyicus in a Juvenile Peregrine Falcon ( Falco peregrinus )

A 6-week-old, parent-reared peregrine falcon ( Falco peregrinus ) was presented with spastic hypertonus of its hind limbs of unknown origin and duration. Radiologic examination revealed smooth periosteal reactions ventrally at thoracic vertebrae 5 to 7. Contrast-enhanced computed tomography identified the swelling as inflammation; antibiotic, antimycotic, anti-inflammatory, and analgesic treatments were initiated, and vitamins and minerals were supplemented. Because the bird's condition did not improve after 10 days, it was euthanatized and submitted for postmortem examination. On histopathologic examination, chronic, active osteomyelitis was diagnosed in thoracic vertebrae 5 to 7, and chronic, active arthritis was present in both the right shoulder and left elbow joints. Staphylococcus hyicus was isolated from these 3 locations, as well as from lungs and liver, indicating a chronic septic staphylococcosis. Although infections with Staphylococcus species are occasional causes of vertebral osteomyelitis in juvenile poultry with active growth plates, it is only sporadically reported in raptors and companion birds. This case report is the first description of the clinical features and diagnostic and pathologic findings in a juvenile peregrine falcon with hematogenous osteomyelitis and arthritis associated with septicemia caused by S hyicus.

Bone Scintigraphic Findings in MRSA Osteomyelitis

Methicillin-resistant Staphylococcus aureus osteomyelitis is a severe form of infection characterized by multifocal or multiple segmental osseous involvement and subperiosteal abscess formation with increased frequency of extraosseous complications including pyomyositis, septic thrombus, and septic arthritis. Bone scan showed long segment and/or multifocal involvement in 4 of 5 patients with areas of abnormal increased and decreased uptake. The clinical presentations included limp and/or pain. Joint involvement was seen in 4 cases. Bone scan abnormalities correlated well with MRI findings of severe and extensive bone disease, abscess formation, muscle, as well as joint and soft tissue involvement.

Findings in patients from Benin with osteomyelitis and polymerase chain reaction-confirmed Mycobacterium ulcerans infection

BACKGROUND

Mycobacterium ulcerans is known to cause Buruli ulcer (BU), a necrotizing skin disease leading to extensive cutaneous and subcutaneous destruction and functional limitations. However, M. ulcerans infections are not limited to skin, and osteomyelitis, still poorly described in the literature, occurs in numerous young patients in Africa.

METHODS

In a retrospective matched case-control study conducted in a highly endemic area in Benin, we analyzed demographic, clinical, biological, and radiological features in all patients with M. ulcerans infections with bone involvement, identified from a cohort of 1257 patients with polymerase chain reaction-proved M. ulcerans infections.

RESULTS

The 81 patients studied had a median age of 11 years (interquartile range, 7-16 years) and were predominantly male (male-female ratio, 2:1). Osteomyelitis was observed beneath active BU lesions (60.5%) or at a distance from active or apparently healed BU lesions (14.8%) but also in patients without a history of BU skin lesions (24.7%). These lesions had an insidious course, with nonspecific clinical findings leading to delayed diagnosis. A comparison with findings in 243 age- and sex-matched patients with BU without osteomyelitis showed that case patients were less likely to have received BCG immunization than controls (33.3% vs 52.7%; P = .01). They were also at higher risk of longer hospital stay (118 vs 69 days; P = .001), surgery (92.6% vs 63.0%; P = .001), and long-term crippling sequelae (55.6% vs 15.2%; P < .001).

CONCLUSIONS

This study highlighted the difficulties associated with diagnosis of M. ulcerans osteomyelitis, with one-fourth of patients having no apparent history of BU skin lesions, including during the current course of illness. Delays in treatment contributed to the high proportion (55.6%) of patients with crippling sequelae.

The Ca, Cl, Mg, Na, and P mass fractions in human bone affected by Ewing's sarcoma

The Ca, Cl, Mg, Na, and P contents and Ca/P, Ca/Mg, Ca/Na, Cl/Ca, and Cl/Na ratios in samples of intact bone, inflamed bone, and Ewing's sarcoma tissue were investigated by neutron activation analysis with high-resolution spectrometry of short-lived radionuclides. In Ewing's sarcoma tissue, the mass fractions of Cl and Na are higher and the mass fractions of Ca and Mg are lower than those of both normal and inflamed bone tissues. It was shown that the levels of Ca and Cl mass fractions and also levels of the Ca/Cl and Cl/Na ratios can be used as an additional test for differential diagnosis between inflamed (or normal) bone and Ewing's sarcoma.

Radiolucent lesions of the mandible: a pattern-based approach to diagnosis

Objectives

Radiolucent mandibular lesions seen on panoramic radiographs develop from both odontogenic and non-odontogenic structures. They represent a broad spectrum of lesions with a varying degree of malignant potential. The purpose of this review is to illustrate the characteristic imaging findings—as well as the clinical and histological features—of common and uncommon radiolucent lesions of the mandible.

Methods

This review article is based on the retrospective evaluation of 11,725 panoramic radiographs seen in our institution during the past 6 years. It provides a comprehensive, practical approach to the radiological interpretation of radiolucent lesions of the mandible. To facilitate the diagnostic approach, we have classified radiolucent lesions into two groups: lesions with well-defined borders and those with ill-defined borders.

Results

Lesion prevalence, age of manifestation, location within the mandible, relationship to dental structures, effect on adjacent structures and characteristic findings at computed tomography (CT), cone beam CT (CBCT) and magnetic resonance imaging (MRI) with diffusion-weighted imaging (DWI) are discussed. Pitfalls including malignant lesions mimicking benign disease and pseudo-lesions are equally addressed.

Conclusion

Knowledge of the characteristic imaging features of radiolucent mandibular lesions narrows the differential diagnosis and is crucial for the identification of those lesions, where biopsy is indicated for definitive histology.

Teaching points

• Panoramic X-rays, CT and MRI are essential for the work-up of radiolucent mandibular lesions.

• Lesion borders, location within the mandible, relationship to dental structures and tissue characteristics on cross-sectional imaging are indispensable to narrow the differential diagnosis.

• High-resolution CT and CBCT play a major role for the assessment of lesion margins and their relationship to important anatomic structures, such as the inferior alveolar nerve.

• Although most radiolucent lesions with well-defined sclerotic borders are benign, MRI may reveal clinically unsuspected malignant disease.