Long-term follow-up of children with chronic non-bacterial osteomyelitis-assessment of disease activity, risk factors, and outcome.

INTRODUCTION: Chronic non-bacterial osteomyelitis (CNO) is an autoinflammatory bone-disease of unknown origin. The National Pediatric Rheumatologic Database (NPRD) collects long-term data of children and adolescents with rheumatic diseases including CNO. OBJECTIVE: To assess characteristics, courses, and outcomes of CNO with onset in childhood and adolescence and to identify outcome predictors. METHODS: From 2015 to 2021 patients with a confirmed diagnosis of CNO, who were registered in the NPRD during their first year of disease and at least one follow-up visit, were included in this analysis and observed for up to 4 years. RESULTS: Four hundred patients with recent diagnosis of CNO were enrolled in the NRPD during the study period. After 4 years, patient data documentation was sufficient to be analyzed in 81 patients. A significant decline of clinical and radiological lesions is reported: at inclusion in the registry, the mean number of clinical lesions was 2.0 and 3.0 MRI lesions per patient. A significant decrease of manifestations during 4 years of follow-up (mean clinical lesions 0.5, p < 0.001; mean MRI lesions 0.9 (p < 0.001)) was documented. A significant improvement of physician global disease activity (PGDA), patient-reported overall well-being, and childhood health assessment questionnaire (C-HAQ) was documented. Therapeutically, an increase of disease-modifying anti-rheumatic drugs over the years can be stated, while bisphosphonates rather seem to be considered as a therapeutic DMARD option in the first years of disease. Only 5-7% of the patients had a severe disease course as defined by a PGDA > = 4. Predictors associated with a severe disease course include the site of inflammation (pelvis, lower extremity, clavicle), increased erythrocyte sedimentation rate, and multifocal disease at first documentation. The previously published composite PedCNO disease activity score was analyzed revealing a PedCNO70 in 55% of the patients at 4YFU. CONCLUSION: An improvement of physician global disease activity (PGDA), patient reported overall well-being and imaging-defined disease activity measures was documented, suggesting that inactivity of CNO disease can be reached. PedCNO score and especially PGDA, MRI-defined lesions and in a number of patients also the C-HAQ seem to be reliable parameters for describing disease activity. The identification of risk factors at the beginning of the disease might influence treatment decision in the future.

Explaining juvenile idiopathic arthritis to paediatric patients using illustrations and easy-to-read texts: improvement of disease knowledge and adherence to treatment.

INTRODUCTION: Juvenile idiopathic arthritis (JIA) is the leading chronic rheumatic disease in childhood. To achieve adherence to therapy, in-depth understanding of disease and treatment options are important. OBJECTIVE: Development of specifically designed illustrations and standardised, easy-to-read texts for children and adolescents with JIA. Education materials were tested for comprehensibility and content validity. We hypothesised that children would be able to increase their knowledge about JIA after presentation of materials. METHODS: The illustrations were designed by a graphic artist and the informative texts consecutively transformed to easy-to-read language. The materials appear as a modular system to allow individualized information for each patient. The illustrations and texts were tested for knowledge gain and improvement of self-efficacy in children affected by JIA/ rheumatic diseases and controls. Health-related quality of life (HRQoL) was tested as an overall assessment of patients' well-being. RESULTS: 46 controls (71% female) and 38 patients (48% female) with a median age of 11 years were tested in a standardised setting. In both groups knowledge gain was significant (controls: t (44) = 11.08, p < 0.001, d = 1.65; patients: t (37) = 7.48, p < 0.001, d = 1.21). The control group had a significantly higher enhancement of disease knowledge compared to patients' group (p = .046) The follow-up testing was only performed in one school class (20 controls) due to Covid-19 pandemic with significant improvement compared to the pre-test results (p = .002). The enhancement of self-efficacy through the teaching session was significantly higher in the patients' group. No impairment of HRQoL was seen. CONCLUSION: Explaining juvenile rheumatic diseases and therapeutic strategies is an important task in paediatric rheumatology. To avoid incomprehensible explanations in medical jargon, illustrations and easy-to-read texts were developed. Standardised presentation of the newly created materials resulted in a significant improvement of disease knowledge in patients and controls in addition to an enhancement of self-efficacy in patients.

First-year follow-up of children with chronic nonbacterial osteomyelitis-an analysis of the German National Pediatric Rheumatologic Database from 2009 to 2018.

OBJECTIVE: To assess the first-year features of patients with chronic nonbacterial osteomyelitis (CNO). METHODS: Patients with a diagnosis of CNO, disease duration of under 13 months, and first registration in the German National Pediatric Rheumatologic Database (NPRD) between 2009 and 2018 were included in this cross-sectional analysis. RESULTS: Of 774 documented patients, 62.8% were female, and all patients had a median age of 11 years. The most affected clinical sites were the tibia (29.7%), pelvis (28.0%), and femur (27.8%). HLA-B27 was positive in 48 of 314 analyzed patients (15.3%). In 406 patients, an X-ray was performed at the first visit; X-ray results showed osteosclerosis/-lysis in 34.0% and hyperostosis in 14.5% of the patients. MRI scans (focal and whole-body scans) were performed in 648 patients, and 81.5% showed a positive TIRM/STIR signal. A total of 84.7% of the patients were administered nonsteroidal anti-inflammatory drugs, 9.6% were administered oral glucocorticoids, 10.8% were administered disease-modifying anti-rheumatic drugs (DMARDs), and 6.1% were administered bisphosphonates. An evaluation of the patient's questionnaire showed an overall well-being (NRS 0-10) of 2.0. The PedCNO disease "activity" score revealed a 70% improvement in variables in 43% of patients in the initial 1-year follow-up. Copresentation with diagnostic criteria of pediatric enthesitis-related arthritis was rare. CONCLUSION: To our knowledge, the NPRD cohort seemed to be the largest cohort of children and adolescents suffering from CNO worldwide. Most patients were treated effectively with NSAIDs, and only a small group of patients was administered additional medication. The patient-defined measures of disease activity had a moderate impact on patients' daily lives. TRIAL REGISTRATION: Not applicable.

New Insights into Adult and Paediatric Chronic Non-bacterial Osteomyelitis CNO.

PURPOSE OF REVIEW: To describe in detail the clinical synopsis and pathophysiology of chronic non-bacterial osteomyelitis and SAPHO syndrome. RECENT FINDINGS: Chronic non-bacterial osteomyelitis (CNO) has been identified as a disease entity for almost 50 years. This inflammatory bone disorder is characterized by osteolytic as well as hyperostotic/osteosclerotic lesions. It is chronic in nature, but it can present with episodic flairs and phases of remission, which have led to the denomination "chronic recurrent osteomyelitis", with its severe multifocal form "chronic recurrent multifocal osteomyelitis" (CRMO). For almost three decades, an infectious aetiology had been considered, since especially Propionibacterium acnes had been isolated from bone lesions of individual patients. However, this concept has been challenged since long-term antibiotic therapy did not alter the course of disease and modern microbiological techniques (including PCR) failed to confirm bone infection as an underlying cause. Over recent years, a profound dysregulation of cytokine expression profiles has been demonstrated in innate immune cells of CNO patients. A hallmark of monocytes from CNO patients is the failure to produce immune regulatory cytokines interleukin-10 (IL-10) and IL-19, which have been linked with genetic and epigenetic alterations. Subsequently, a significant upregulation of pro-inflammatory, NLRP3 inflammasome-dependent cytokines (IL-1ß and TNF-α), has been demonstrated. The current knowledge on CNO, the underlying molecular pathophysiology, and modern imaging strategies are summarized; differential diagnoses, treatment options, outcome measures, as well as quality of life studies are discussed.