Chronic Nonbacterial Osteomyelitis Research Articles

Characteristics, Treatment Options, and Outcomes of Chronic Non-bacterial Osteomyelitis in Children

Chronic non-bacterial osteomyelitis (CNO) is an autoinflammatory bone disease most prevalent in children. In this review, we seek to highlight the most recent advances in the understanding of the pathophysiology, treatment, and outcomes of CNO. Recent observations support a pathophysiologic framework involving imbalanced expression of pro-inflammatory versus anti-inflammatory cytokines, thereby inducing increased differentiation and activation of osteoclasts. Although no medication nor protocol is yet specifically indicated in the treatment of CNO, there exists an expanding body of evidence for agents exerting their effects via interference with these pro-inflammatory pathways (namely non-steroidal anti-inflammatory drugs, disease-modifying anti-rheumatic drugs, bisphosphonates, and biologics), highlighted herein. With an incidence rivaling that of bacterial osteomyelitis, childhood CNO represents an important and growing field of study. Once thought to be benign and self-limiting, CNO is now recognized to follow a relapsing and remitting course in the majority of children, and to carry substantial risk of irreversible growth and bone sequelae. Perhaps of greatest importance to the study of CNO treatment is the recent development of the Childhood Arthritis and Rheumatology Research Alliance (CARRA) consensus treatment plans, the implementation of which will allow for prospective comparative effectiveness studies and, ultimately, the development of standardized treatment protocols.

Differential diagnosis portfolio of a pediatric rheumatologist: eight cases, eight stories.

There is no single diagnostic test for any rheumatic disease. The diagnosis of a rheumatic disease is made by the sum of the findings in history, physical examination, laboratory, and imaging tests. A differential diagnosis list in pediatric rheumatology is quite long and mainly includes malignant, infectious, and inherited metabolic disorders. We aim to present cases that were referred to a pediatric rheumatology outpatient clinic with provisional diagnosis of a rheumatic disease but finally diagnosed with a non-rheumatic disease in order to emphasize the importance of differential diagnoses. Eight cases were presented in this manuscript. Five cases were referred with the provisional diagnosis of juvenile idiopathic arthritis. Sarcoidosis, chronic non-bacterial osteomyelitis, and autoinflammatory disease were the provisional referral diagnoses in three patients. Definitive diagnoses of the patients were as follows: acute lymphoblastic leukemia (two cases), bilineage acute leukemia, Hodgkin lymphoma, brucellosis, mucolipidosis type III, anhidrotic ectodermal dysplasia, and Freiberg disease. In children presenting with rheumatic complaints malignant, infectious and inherited metabolic disorders should always be in the differential diagnosis list of a pediatric rheumatologist. Alternative diagnoses should always be considered even in patients with a rheumatic disease when the patient does not respond to treatment or follows an unusual clinical course. Key Points • Diagnosis of a rheumatic disease is made by exclusion of all other pathologies. • Malignant and infectious diseases may mimic the signs and symptoms of a rheumatic disease.

High prevalence of rare FBLIM1 gene variants in an Italian cohort of patients with Chronic Non-bacterial Osteomyelitis (CNO)

BackgroundFBLIM1 gene has been recently demonstrated to be involved in the pathogenesis of bone sterile inflammation. The aim of the study is to evaluate the prevalence of FBLIM1 gene variants in a cohort of 80 Italian patients with Chronic Non-bacterial Osteomyelitis (CNO).MethodsThe coding regions of FBLIM1 gene were sequenced in a cohort of 80 patients with CNO using DNA extracted from blood lymphocytes, and PCR products were sequenced. Only rare (global MAF < 2%), coding variants detected were considered. Clinical evaluation of patients with rare variants and those without was performed. Fisher’s exact test was used to compare categorical and ordinal data, and Student’s t-test was used to analyze continuous data.ResultsEighteen out of 80 patients (~ 22%) presented at least one rare coding variant in FBLIM1. Eight patients presented a variant never associated before with CNO. All patients presented classical features of CNO and no statistical difference between patients with presence of FBLMI1 variants and those without were found in terms of clinical manifestation, treatment, and outcome.ConclusionConsidering the high frequency of rare variants in our CNO cohort, our data seem to confirm a possible role of FBLIM1 in the pathogenesis of CNO suggesting that CNO is a disorder of chronic inflammation and imbalanced bone remodeling.

The Possible Relationship Between Familial Mediterranean Fever and Chronic Nonbacterial Osteomyelitis: Coincidence or Coexistence?

Chronic nonbacterial osteomyelitis (CNO) is an inflammatory disease characterized by recurrent attacks and remissions due to sterile bone inflammation. The CNO may be accompanied by various inflammatory diseases. The aims of our study were to determine the clinical, laboratory, and radiological characteristics of children with CNO, and to investigate the possible effect of concomitant diseases on the course of CNO. Twenty-three patients who were diagnosed with CNO between 2012 and 2019 were analyzed. Demographic characteristics, clinical courses, laboratory and imaging findings, and concomitant diseases were recorded. The characteristics of the CNO patients with and without concomitant diseases were compared. The mean ± SD age of patients at the time of diagnosis and the last follow-up was 10.46 ± 4.1 and 12.47 ± 4.47 years, respectively. The median (range) time interval between disease onset and diagnosis was 5.33 (1-55) months. The mean ± SD duration of disease was 24.71 ± 16.76 months. Twelve patients (52.2%) were male. The most commonly affected areas were femur (74%), tibia/fibula (74%), and pelvis (52.2%). Age at symptom onset, age at diagnosis, mean number of lesions, presence of sacroiliitis, acute phase reactants at the start of disease, clinical and radiological remission rates, and treatment responses were not significantly different between the 13 patients with concomitant diseases and those without. Eight patients (34.8%) had familial Mediterranean fever (FMF), and all of them had exon 10 mutations. Four patients (17.4%) had juvenile spondylarthritis, one had inflammatory bowel disease, and one had psoriatic arthritis as concomitant diseases. Clinical remission was achieved in 19 patients (82.6%) and complete remission in 11 patients (47.8%) at the time of follow-up. In our cohort, half of the patients with CNO had concomitant diseases, with FMF being the most common. We think that the coexistence of FMF and CNO is not a coincidental one and that both may result due to an abnormality of a common pathogenetic pathway.

How nonbacterial osteomyelitis could be discriminated from tuberculosis in the early stages: the simple algorithm.

Chronic nonbacterial osteomyelitis (CNО) and tuberculous osteomyelitis (TBO) are both primarily chronic inflammatory bone diseases with similar clinical and radiological findings, but entirely different in aetiology, pathogenesis, treatment, and outcomes. Our study aimed to evaluate the clinical and laboratory features which could discriminate the CNO and TBO. The study included 124 patients-91 with CNO and 33 with TBO. All patients underwent routine blood tests: WBC, platelets, ESR, C-reactive protein, haemoglobin, and imaging. The ability of each variable to discriminate CNO from TBO was evaluated with sensitivity and specificity analysis, AUC-ROC analysis, and calculating the odds ratio. Patients with TBO had less number of bone foci (p = 0.0000001), onset age (p = 0.00001), rarely articular involvement (p = 0.01), lower haemoglobin level (p = 0.02), higher incidence of TBO in the male subjects (p = 0.002), and higher leukocyte bands (p = 0.0000001). TBO is rarely characterized by spine (p = 0.0009), foot (p = 0.01), and clavicula (p = 0.047) involvement. The diagnostic rule: criteria allowing to differentiate NBO from TBO are negative bone microbiota tests (sensitivity-100.0%, specificity-100.0%) or major discriminative criteria or clavicula involvement alone (sensitivity-11.0%, specificity-100.0%) and at least four from the five additional criteria: number of foci > 1.0 (p = 0.00002), WBC ≤ 11.0 (p = 0.004), neutrophil bands ≤ 120.0 × 106/l (p = 0.002), lymphocytes ≤ 52% (p = 0.0005), and CRP > 0.2mg/l (p = 0.003). All patients with monofocal CNO required bone biopsy with microbiology assessment. The created provisional criteria may help to discriminate TBO and CNO and should be used only with other known diagnostic tools. Key Points • Nonbacterial osteomyelitis and tuberculous osteomyelitis are both primarily chronic inflammatory bone diseases with similar presentations. • Nonbacterial osteomyelitis and tuberculous osteomyelitis may be associated with other immune-mediated diseases. • Only bone biopsy can confirm and discriminate both conditions. All patients with monofocal CNO required bone biopsy with microbiology assessment.

Pamidronate in chronic non-bacterial osteomyelitis: a randomized, double-blinded, placebo-controlled pilot trial

Objective This is the first randomized double-blinded, placebo-controlled pilot trial to investigate the efficacy of pamidronate in reducing radiological and clinical disease activity in chronic non-bacterial osteomyelitis (CNO). Method Patients received pamidronate or placebo at baseline and weeks 12 and 24. Whole-body magnetic resonance imaging was performed at baseline and weeks 12 and 36, and computed tomography of the anterior chest wall (ACW) at baseline and week 36. Radiological disease activity was systematically scored in the ACW and spine. Patient-reported outcomes [visual analogue scale (VAS) pain, VAS global health, Health Assessment Questionnaire (HAQ), EuroQol-5 Dimensions (EQ-5D), and 36-item Short-Form Health Survey (SF-36)] and biomarkers of bone turnover and inflammation were assessed at baseline and weeks 1, 4, 12, 24, and 36. Data are expressed as median [interquartile range]. Results Fourteen patients were randomized and 12 were analysed. From baseline to week 36, the radiological disease activity score in the ACW decreased from 5 [4–7] to 2.5 [1–3] in the pamidronate group, but did not change in the placebo group (p = 0.04). From baseline to week 36, VAS pain and VAS global health tended to decrease more in the pamidronate than in the placebo group (p = 0.11, p = 0.08). Physical functioning (HAQ) and health-related quality of life (EQ-5D, SF-36) did not change. Biomarkers of bone turnover decreased only in the pamidronate group (p ≤ 0.02). Conclusion Pamidronate may improve radiological and clinical disease activity in CNO. Methods to score radiological disease activity in adult CNO were suggested. Clinical Trials: NCT02594878

Genetic variants in FBLIM1 gene do not contribute to SAPHO syndrome and chronic recurrent multifocal osteomyelitis in typical patient groups

BackgroundSyndrome of synovitis acne pustulosis hyperostosis osteitis (SAPHO) and chronic recurrent multifocal osteomyelitis (CRMO) present two diseases of a dermatologic and rheumatologic spectrum that are variable in manifestation und therapeutic response. Genetic risk factors have long been assumed in both diseases, but no single reliable factor has been identified yet. Therefore, we aimed to clinically characterize a patient group with syndrome of synovitis acne pustulosis hyperostosis osteitis (SAPHO) (n = 47) and chronic recurrent multifocal osteomyelitis (CRMO)/ chronic non-bacterial osteomyelitis (CNO) (n = 9) and analyze a CRMO candidate gene.MethodsClinical data of all patients were collected and assessed for different combinations of clinical symptoms. SAPHO patients were grouped into categories according to the acronym; disease-contribution by pathogens was evaluated. We sequenced coding exons of FBLIM1.ResultsPalmoplantar pustular psoriasis (PPP) was the most common skin manifestation in CRMO/CNO and SAPHO patients; most SAPHO patients had sterno-costo-clavicular hyperostosis. The most common clinical category of the acronym was S_PHO (n = 26). Lack of pathogen detection from bone biopsies was more common than microbial isolation. We did not identify autosomal-recessive FBLIM1 variants.ConclusionsS_PHO is the most common combination of symptoms of its acronym. Genetic analyses of FBLIM1 did not provide evidence that this gene is relevant in our patient group. Our study indicates the need to elucidate SAPHO’s and CRMO/CNO’s pathogenesis.

Clinical Characteristics of Acne Fulminans Associated With Chronic Nonbacterial Osteomyelitis in Pediatric Patients.

Acne fulminans (AF) is a rare, explosive systemic form of acne. Chronic nonbacterial osteomyelitis (CNO) or chronic recurrent multifocal osteomyelitis (CRMO) is a primarily pediatric autoinflammatory disorder characterized by sterile osteolytic bone lesions. Concomitant occurrence of CNO/CRMO and AF is very rare, and little is known about the epidemiological and clinical particularities of this association. The aim of this retrospective observational study was to describe the characteristics of pediatric patients with CNO/CRMO associated to AF. Electronic mailing lists of French medical societies were used to call for patients with CNO/CRMO and AF. A search for published patients with CNO/CRMO and AF was performed by screening PubMed. We identified 5 original patients and 10 patients from the literature. All patients were adolescent boys. Mean age at disease onset was 14.8 years. Nine of 15 patients had received isotretinoin before the sudden onset of AF. Osteoarticular symptoms appeared within < 1-3 months after the onset of AF. The mean numbers of clinical and radiological bone lesions were 3.6 and 5.6, respectively. The percentages of patients with involvement of vertebrae, pelvis, chest, and cranial were 40%, 40%, 33.3%, and 6.6%, respectively. Arthritis was observed in 69.2% of patients and sacroiliac arthritis in 46.2%. CNO/CRMO associated to AF occurs predominantly in male adolescents and is characterized by frequent involvement of the axial skeleton and arthritis. Epidemiological and clinical features of these patients differ from general CNO/CRMO cohorts. Clinical management requires careful handling of isotretinoin doses.

A rare case of chronic nonbacterial osteomyelitis of the mandible in a young adult male

Chronic nonbacterial osteomyelitis (CNO), also known as chronic recurrent multifocal osteomyelitis, is a rare disease of unknown etiology mainly affecting girls with a mean age of 10 years. The disease is characterized by nonbacterial osteolytic lesions and swelling of the adjacent soft tissues and has nonstandard treatment protocols. Unifocal CNO typically involves the mandible. Mandibular CNO is difficult to differentiate from bacterial osteomyelitis because of its similar radiographic profile and clinical symptoms. Therefore, magnetic resonance imaging (MRI) should be considered if infectious osteomyelitis has not been diagnosed by laboratory examination. Our patient was a young adult man with mandibular CNO presented with atypical bone fragments on MRI. Clinical symptoms improved within 3 days after surgical intervention to remove the fragments and treatment with a nonsteroidal anti-inflammatory drug (NSAID). NSAID therapy was discontinued at postoperative day 20, and the patient has experienced no recurrences at 5 months after surgery.

Response of Different Treatment Protocols to Treat Chronic Non-Bacterial Osteomyelitis (CNO) of the Mandible in Adult Patients: A Systematic Review.

(1) Background: Chronic non-bacterial osteomyelitis (CNO) is an autoinflammatory bone disease of finally unknown etiology, which can occur alone or related with syndromes (chronic recurrent multifocal osteomyelitis—CRMO; synovitis, acne, pustulosis, hyperostosis and osteitis syndrome—SAPHO). The involvement of the mandible is rather rare. (2) Methods: We carried out a systematic literature search on CNO with mandibular involvement, according to the “Preferred Reporting Items for Systematic Reviews and Meta-Analyses” (PRISMA) guidelines, considering the different synonyms for CNO, with a special focus on therapy. (3) Results: Finally, only four studies could be included. A total of 36 patients were treated in these studies—therefore, at most, only tendencies could be identified. The therapy in the included works was inconsistent. Various therapies could alleviate the symptoms of the disease. A complete remission could only rarely be observed and is also to be viewed against the background of the fluctuating character of the disease. The success of one-off interventions is unlikely overall, and the need for long-term therapies seems to be indicated. Non-steroidal anti-inflammatory drugs (NSAIDs) were not part of any effective therapy. Surgical therapy should not be the first choice. (4) Conclusions: In summary, no evidence-based therapy recommendation can be given today. For the future, systematic clinical trials on therapy for CNO are desirable.

Prevalence of cranial involvement in a cohort of Italian patients with chronic non-bacterial osteomyelitis

Chronic non-bacterial osteomyelitis (CNO) is a non-infectious inflammatory disease characterised by uni- or multi-focal bone lytic lesions. CNO mainly affects metaphysis of long bones, pelvis and shoulder girdle. Neurocranium lesions are extremely rare. The objective of the study is to describe the prevalence and clinical manifestations of CNO patients with neurocranium involvement in an Italian cohort of CNO patients. This is a retrospective study. Medical records of patients with CNO admitted to eight paediatric rheumatology centres were reviewed. Among 86 patients with CNO enrolled in the study, three of them were female and presented neurocranium involvement - multifocal lesions. Two out of the 3 patients were completely asymptomatic for cranial involvement, while one of the 3 complained of cranial bossing. Cranial involvement was detected with bone scintigraphy and then confirmed by magnetic resonance imaging and/or computed tomography. Two patients presented fever and two with skin manifestations. Laboratory inflammatory markers were increased in two of them. All patients underwent bone biopsy confirming the diagnosis. They all received NSAIDs. Two patients received corticosteroids and then methotrexate and achieved clinical remission, while one patient received pamidronate. This is the first report of neurocranium involvement in a cohort of patients affected by CNO. In our cohort no patient showed significant signs attributable to cranial involvement.

A Targeted Genetic Association Study of the Rare Type of Osteomyelitis

Chronic nonbacterial osteomyelitis is a rare bone disorder that can be found in the jaw. It is often associated with systemic conditions, including autoimmune deficiencies. However, little is known about how the genetic and immunologic background of patients influences the disease. Here, we focus on human leukocyte antigen (HLA), killer cell immunoglobulin-like receptors (KIRs), and their specific combinations that have been difficult to analyze owing to their high diversity. We employed a recently developed technology of simultaneous typing of HLA alleles and KIR haplotype and investigated alleles of the 35 HLA loci and KIR haplotypes composed of centromeric and telomeric motifs in 18 cases and 18 controls for discovery and 472 independent controls for validation. We identified an amino acid substitution of threonine at position 94 of HLA-C in combination with the telomeric KIR genotype of haplotype tA01/tB01 that had significantly higher frequency (>20%) in the case population than in both control populations. Multiple logistic regression analysis based on a dominant model with adjustments for age and sex revealed and validated its statistical significance and high predictive accuracy (C-statistic ≥0.85). Structure-based analysis revealed that the combination of the amino acid change in HLA-C and the telomeric genotype tA01/tB01 could be associated with lower stability of HLA-C. This is the first case-control study of a rare disease that employed the latest sequencing technology enabling simultaneous typing and investigated amino acid polymorphisms at HLA loci in combination with KIR haplotype.

Pediatric chronic nonbacterial osteomyelitis of the mandible: Seattle Children\u2019s hospital 22-patient experience

BackgroundStudies evaluating treatment responses for chronic nonbacterial osteomyelitis (CNO) are lacking. We aimed to measure and compare response rates of medical treatments, time to response of medical treatments among patients with CNO of the mandible, and describe bacterial contamination rates from biopsy.MethodsWe conducted a retrospective chart review of all patients diagnosed with CNO of mandible between 2003 and 2017 and extracted demographic, clinical, laboratory, imaging and surgical data. Detailed medication use and response to medications were recorded. The primary outcome was response to medical treatments defined as improvement of presenting symptoms, inflammatory markers, and imaging if available. Medical treatments included nonsteroidal anti-inflammatory drugs (NSAIDs), glucocorticoids, disease modifying anti rheumatic drugs (DMARDs), anti-tumor necrosis factor (TNF) therapy, and pamidronate. Descriptive analysis was performed when appropriate. Multivariable logistic regression and Kaplan-Meier curves were applied to compare the responses to medical treatments and time to full response.ResultsWe identified 22 patients with a median age of 11 and 36% were female. Four patients (18%) had multifocal bone lesions. CT findings (n = 21) showed lytic lesions (62%) and sclerosis (90%). MRI (n = 14) revealed hyperintensity within bone marrow (100%), soft tissue (71%) and bony expansion (71%). Non-antibiotic treatments including NSAIDs (n = 18), glucocorticoids (n = 10), DMARDs (n = 9), anti-TNF therapy (n = 5) and pamidronate (n = 6) were applied. Rates of full responses to anti-TNF therapy (60%) and pamidronate (67%) were higher than that to NSAIDs (11%) (p < 0.05). Patients receiving pamidronate responded more rapidly than those receiving anti-TNF therapy (median two vs 17 months, p = 0.01) when there was a full response. All had bone biopsies. Intraoral biopsy was performed in 12 of 13 operated in our center and the most common contaminants were Neisseria spp and Streptococcus viridians.ConclusionBoth anti-TNF and pamidronate appeared superior to NSAIDs alone in treating mandibular CNO. Patients receiving pamidronate responded faster than those receiving anti-TNF therapy.

The off-label use of anakinra in pediatric systemic autoinflammatory diseases.

Interleukin 1 (IL-1), a central mediator of innate immunity, is considered a master cytokine of local and systemic inflammation. IL-1 has emerged as pivotal in the pathogenesis of autoinflammatory diseases (AIDs), and blockade of its pathway has become a crucial target for therapy. Anakinra (ANA), a recombinant IL-1β receptor antagonist, was the first anti-IL-1 agent employed in clinical practice. ANA is currently approved for the treatment of rheumatoid arthritis, systemic juvenile idiopathic arthritis, adult-onset Still’s disease, and cryopyrin-associated autoinflammatory syndrome. It has also been successfully used for off-label treatment of various monogenic, polygenic, or undefined etiology systemic AIDs.This review describes currently available evidence for the off-label use of ANA in pediatric rheumatologic diseases. Specifically, the use of ANA in Kawasaki disease, idiopathic recurrent pericarditis, Behçet disease, monogenic AIDs, undifferentiated AIDs, chronic non-bacterial osteomyelitis, macrophage activation syndrome, and febrile infection-related epilepsy, in terms of its safety and efficacy. In selected pediatric rheumatic disorders, the off-label administration of ANA appears to be effective and safe. In order to control severe and/or relapsing disease, ANA should be considered as a valuable treatment option in children suffering from rare inflammatory diseases. However, currently available data consist of retrospective studies and short case series; thus, randomized controlled trials and larger series with long-term follow up are mandatory to better assess the efficacy and cost effectiveness of ANA in these challenging patients.

The peculiarities and treatment outcomes of the spinal form of chronic non-bacterial osteomyelitis in children: a retrospective cohort study.

Chronic non-bacterial osteomyelitis (CNO) is a group of immune-mediated diseases which appears in bone inflammation, destruction and some orthopaedic consequences, especially in the cases of spinal involvement. This study is to compare characteristics and treatment outcomes of CNO patients with spinal involvement. The retrospective cohort study included data from 91 pediatric patients with CNO. The diagnosis is based on Jannson's criteria with morphological confirmation (nonspecific chronic inflammation). Spine involvement detected by X-ray, computed tomography, magnetic resonance imaging, and bone scan in 29 (31.9%) patients. No differences in the family history, concomitant immune-mediated diseases between spinal (SpCNO) and peripheral (pCNO) forms of CNO have been revealed. Only 5 (10.2%) SpCNO patients (10.2%) had monofocal monovertebral involvement. The main risk factors of spinal involvement were female sex: RR = 2.0 (1.1; 3.9), sensitivity (Se) = 0.66, specificity (Sp) = 0.6; multifocal involvement: RR = 2.1 (0.9; 5.0), Se = 0.83, Sp = 0.37; no foot bones involvement: RR = 3.1 (1.3; 7.5), Se = 0.83, Sp = 0.5; sternum involvement RR = 2.3 (1.3; 4.1), Se = 0.24, Sp = 0.94. In the linear regression analysis only female sex (p = 0.005), multifocal involvement (p = 0.000001) and absence of foot bones involvement (p = 0.000001) were independent risk factors of spinal involvement (p = 0.000001). The response rate on bisphosphonates and tumor necrosis factor-a inhibitors was 90.9% and 66.7%, consequently. Only 4/29 (13.8%) SpCNO patients underwent surgery due to severe spinal instability or deformities. The spinal involvement is frequent in CNO and could be crucial for choosing a treatment strategy. Bisphosphonates and TNFa-inhibitors could be effective treatment options for severe SpCNO.

Proceedings From the Clinical and Scientific Innovations in Oral and Maxillofacial Surgery Conference 2019

Proceedings From the Clinical and Scientific Innovations in Oral and Maxillofacial Surgery Conference 2019

A Pilot Study of Infrared Thermal Imaging to Detect Active Bone Lesions in Children With Chronic Nonbacterial Osteomyelitis

Chronic nonbacterial osteomyelitis (CNO) is an autoinflammatory bone disease. An inexpensive and rapid imaging tool, infrared thermal imaging, was evaluated for its utility to detect active bone lesions in extremities of children with CNO. Children with suspected active CNO and healthy controls were enrolled. All subjects underwent infrared thermal imaging of the lower extremities. Patients in the CNO group also received a magnetic resonance imaging (MRI) examination. Hyperintensity within bone marrow on a fluid-sensitive T2-weighted MRI sequence was considered confirmatory for inflammation. Infrared thermal data were analyzed using custom software by dividing the leg below the knee into 3 equal segments longitudinally and adding the distal femur segment as an equal length above the knee. Median and 95th percentile temperatures were recorded for each leg segment. Temperature differences between inflamed and uninflamed segments in all subjects (both intersubject and intrasubject) were evaluated using a linear mixed-effects model. Thirty children in the suspected/known CNO group and 31 healthy children were enrolled. In the healthy control group, males had significantly higher temperature in their lower extremities than females (P < 0.05). There was no difference in temperature detected between inflamed leg segments of patients with CNO versus uninflamed leg segments of the healthy control group. However, within the CNO group, significantly higher temperatures were detected for inflamed versus uninflamed distal tibia/fibula segments (P < 0.01). Children with active CNO lesions in the distal tibia/fibula exhibited higher regional temperatures on average than healthy extremities. Larger studies are warranted to further evaluate the clinical utility of infrared thermal imaging for CNO detection.

Chronic non-bacterial osteomyelitis of clavicle

The patient was a 10-year-old girl with pain and swelling of the left clavicle. The physical examination was normal except swelling and tenderness of the left clavicular region. All the...

Development of a Scoring Tool for Chronic Nonbacterial Osteomyelitis Magnetic Resonance Imaging and Evaluation of its Interrater Reliability

Serial magnetic resonance imaging (MRI) examinations are often needed in chronic nonbacterial osteomyelitis (CNO) to determine the objective response to treatment. Our objectives in this study were (1) to develop a consensus-based MRI scoring tool for clinical and research use in CNO; and (2) to evaluate interrater reliability and agreement using whole-body (WB)-MRI from children with CNO. Eleven pediatric radiologists discussed definitions and grading of signal intensity, size of signal abnormality within bone marrow, and associated features on MRI through monthly conference calls and a consensus meeting, using a nominal group technique in July 2017. WB-MRI scans from children with CNO were deidentified for training reading and an interrater reliability study. The reading by each radiologist was conducted in a randomized order. Interrater reliability for abnormal signal and severity were assessed using free-marginal κ statistics. Radiologists reached a consensus on grading CNO-specific MRI findings and on describing bone units based on anatomy. A total of 45 sets of WB-MRI scans, including 4 sets of non-CNO MRI examinations, were selected for the final reading. The mean κ of each category of bones was > 0.7 with majority > 0.9 demonstrating substantial/almost perfect interrater reliability of readings among radiologists. The agreement on signal intensity and the size of signal abnormality within the most commonly affected bones (femur and tibia) were lower than those of other bones. The chronic nonbacterial osteomyelitis magnetic resonance imaging scoring (CROMRIS) tool is a comprehensive standardized scoring tool for MRI in children with CNO. Our interrater study demonstrated good interrater reliability and agreement of readings.

Chronic nonbacterial osteomyelitis in children: a multicenter case series.

Chronic nonbacterial osteomyelitis (CNO) is a primary autoinflammatory bone disease that presents more frequently in children and is characterized by inflammatory bone lesions in the absence of an infectious etiology. There is little information of this disease in Latin America. The objective of the study was to evaluate demographic, clinical, laboratory, imaging, histopathology characteristics, and treatment responses of pediatric CNO patients. The clinical records of 19 patients with CNO diagnosed between 2007 and 2019 at three tertiary centers in Santiago, Chile were reviewed. The median age of onset was 10years and 47% were female. Median delay in diagnosis was 12months. All patients had a pattern of recurrent multifocal disease. 37% of patients had positive antinuclear antibodies and 16% HLA-B27 positivity. 21% of patients presented arthritis or other rheumatologic comorbidity, although no association with psoriasis, inflammatory bowel disease (IBD) or palmoplantar pustulosis (PPP) was observed. Eighteen patients received treatment with nonsteroidal anti-inflammatory drugs with partial response. Twelve patients received methotrexate, and half of them received steroids at the same time reaching remission in 50%. Of the five patients who received bisphosphonates, 60% achieved remission. All four patients who received adalimumab had comorbid arthritis and 75% achieved remission. In a series of Chilean children with CNO, all patients presented with multifocal lesions. Comorbid autoimmune diseases including arthritis were frequent, but no association was observed with psoriasis, IBD, or PPP.