Proposed diagnostic criteria for the diagnosis of hypophosphatasia in children and adolescents: results from the HPP International Working Group.

Hypophosphatasia (HPP) is a rare inborn error of metabolism that presents variably in both age of onset and severity. HPP is caused by pathogenic variants in the ALPL gene, resulting in low activity of tissue nonspecific alkaline phosphatase (TNSALP). Patients with HPP tend have a similar pattern of elevation of natural substrates that can be used to aid in diagnosis. No formal diagnostic guidelines currently exist for the diagnosis of this condition in children, adolescents, or adults. The International HPP Working Group is a comprised of a multidisciplinary team of experts from Europe and North America who have expertise in the diagnosis and management of patients with HPP. This group reviewed 93 papers through a Medline, Medline In-Process, and Embase search for the terms "HPP" and "hypophosphatasia" between 2005 and 2020 and that explicitly address either the diagnosis of HPP in children, clinical manifestations of HPP in children, or both. Two reviewers independently evaluated each full-text publication for eligibility and studies were included if they were narrative reviews or case series/reports that concerned diagnosis of pediatric HPP or included clinical aspects of patients diagnosed with HPP. This review focused on 15 initial clinical manifestations that were selected by a group of clinical experts.The highest agreement in included literature was for pathogenic or likely pathogenic ALPL variant, elevation of natural substrates, and early loss of primary teeth. The highest prevalence was similar, including these same three parameters and including decreased bone mineral density. Additional parameters had less agreement and were less prevalent. These were organized into three major and six minor criteria, with diagnosis of HPP being made when two major or one major and two minor criteria are present.

The challenge of hypophosphatasia diagnosis in adults: results from the HPP International Working Group Literature Surveillance.

Hypophosphatasia (HPP) is an inborn error of metabolism caused by reduced or absent activity of the tissue non-specific alkaline phosphatase (TNSALP) enzyme, resulting from pathogenic variants in the ALPL gene. Clinical presentation of HPP is highly variable, including lethal and severe forms in neonates and infants, a benign perinatal form, mild forms manifesting in adulthood, and odonto-HPP. Diagnosis of HPP remains a challenge in adults, as signs and symptoms may be mild and non-specific. Disease presentation varies widely; there are no universal signs or symptoms, and the disease often remains underdiagnosed or misdiagnosed, particularly by clinicians who are not familiar with this rare disorder. The absence of diagnosis or a delayed diagnosis may prevent optimal management for patients with this condition. Formal guidelines for the diagnosis of adults with HPP do not exist, complicating efforts for consistent diagnosis. To address this issue, the HPP International Working Group selected 119 papers that explicitly address the diagnosis of HPP in adults through a Medline, Medline In-Process, and Embase search for the terms "hypophosphatasia" and "HPP," and evaluated the pooled prevalence of 17 diagnostic characteristics, initially selected by a group of HPP clinical experts, in eligible studies and in patients included in these studies. Six diagnostic findings showed a pooled prevalence value over 50% and were considered for inclusion as major diagnostic criteria. Based on these results and according to discussion and consideration among members of the Working Group, we finally defined four major diagnostic criteria and five minor diagnostic criteria for HPP in adults. Authors suggested the integrated use of the identified major and minor diagnostic criteria, which either includes two major criteria, or one major criterion and two minor criteria, for the diagnosis of HPP in adults.

Hypophosphatasia diagnosis: current state of the art and proposed diagnostic criteria for children and adults.

BACKGROUND: This manuscript provides a summary of the current evidence to support the criteria for diagnosing a child or adult with hypophosphatasia (HPP). The diagnosis of HPP is made on the basis of integrating clinical features, laboratory profile, radiographic features of the condition, and DNA analysis identifying the presence of a pathogenic variant of the tissue nonspecific alkaline phosphatase gene (ALPL). Often, the diagnosis of HPP is significantly delayed in both adults and children, and updated diagnostic criteria are required to keep pace with our evolving understanding regarding the relationship between ALPL genotype and associated HPP clinical features. METHODS: An International Working Group (IWG) on HPP was formed, comprised of a multidisciplinary team of experts from Europe and North America with expertise in the diagnosis and management of patients with HPP. Methodologists (Romina Brignardello-Petersen and Gordon Guyatt) and their team supported the IWG and conducted systematic reviews following the GRADE methodology, and this provided the basis for the recommendations. RESULTS: The IWG completed systematic reviews of the literature, including case reports and expert opinion papers describing the phenotype of patients with HPP. The published data are largely retrospective and include a relatively small number of patients with this rare condition. It is anticipated that further knowledge will lead to improvement in the quality of genotype-phenotype reporting in this condition. CONCLUSION: Following consensus meetings, agreement was reached regarding the major and minor criteria that can assist in establishing a clinical diagnosis of HPP in adults and children.

Do subjective components of disease activity contribute to heterogeneity in opioid prescriptions in inflammatory rheumatic diseases? Results from ESPOIR and DESIR cohorts.

OBJECTIVES: To determine whether subjective components of disease activity are associated with heterogeneity in opioid prescription in inflammatory rheumatic diseases (IRDs) after accounting for objective inflammatory markers. METHODS: Data from two prospective observational cohorts of early IRDs (ESPOIR for rheumatoid arthritis (RA) and DESIR for spondyloarthritis (SpA)) were included. Opioid prescription duration (converted to monthly binary opioid prescription), disease activity (Disease activity score 28 (DAS28) for RA; Axial spondyloarthritis disease activity score-C-reactive protein (ASDAS-CRP) for SpA) and its components were measured respectively at 13 and 9 occasions spanning 10- and 6-years of follow-up. Group-based trajectory modelling defined opioid-prescription trajectories and mixed-models characterised the evolution of disease activity and its subjective components by opioid-prescription trajectories. RESULTS: Four distinct opioid-prescription trajectories: no/low (60.5% and 54.3%), declining (14.7% and 15.8%), augmenting (11.9% and 10.7%), and persistent (12.9% and 19.1%) were identified in RA and SpA respectively (60% were prescribed opioids at least once). Those with regular opioid prescriptions (up to 30%) are often older, less educated, have higher BMI and worse disease. No/low trajectory was the reference for examining evolution of disease activity and subjective components (n=810 RA, n=679 SpA). In IRDs, consistently higher disease activity throughout follow-up were seen with persistent (DAS28(ß=0.4-0.8); ASDAS-CRP(ß=0.4-0.6)), and augmenting (DAS28(ß=0.2-0.5); ASDAS-CRP(ß=0.3-0.6)) trajectories and until 3- or 4-years of follow-up (DAS28(ß=0.3-0.4); ASDAS-CRP(ß=0.2-0.3)) with declining trajectory. Likewise, despite accounting for objective inflammation, subjective components had worse scores over follow-up in augmenting and persistent trajectory. CONCLUSIONS: Non-inflammatory pain mechanisms amplify subjective outcomes, thus, worsening composite measures like disease activity.

Efficacy and management of tocilizumab in polymyalgia rheumatica: results of a multicenter retrospective observational study.

OBJECTIVES: The efficacy of anti-IL6 receptors such as Tocilizumab (TCZ) was demonstrated in patients with Polymyalgia Rheumatica (PMR) in two recent randomized controlled trials. The objective of this multicentre retrospective study was to assess the efficacy of TCZ in PMR patients requiring GC-sparing treatment, as well as different strategies for TCZ withdrawal. METHODS: We conducted a multicentre study in French tertiary health care departments for patients with PMR. PMR patients receiving off-label TCZ between 2015 and 2022 were included. The primary end point was the proportion of patients tapering to glucocorticoids (GCs) ≤5mg/day 6 months after the first TCZ infusion. The secondary endpoints were the proportion in whom GC was discontinued during follow-up, and the proportion of patients in whom TCZ was discontinued. RESULTS: Fifty-three PMR patients were included. Thirty-one (31) patients suffered from active PMR despite csDMARDs. GCs were ≤5mg/day in 77% of the patients (95% confidence interval [CI95%]: 36-89) at 6 months, and in 97% of the patients at 12 months. Six and 12 months after the first TCZ infusion, the proportions of GC-free patients were 22.5% (CI95%: 12.7-37.8) and 58.3% (CI95%: 43.2-74.1), respectively. Among TCZ withdrawal strategies, TCZ infusion spacing and TCZ dose reduction were more successful (success in 87% and 79% of attempts, respectively) than TCZ discontinuation (success in 52% of attempts; p= 0.012 and p= 0.039, respectively). CONCLUSION: In GC-dependent PMR patients, treatment with TCZ led to a drastic decrease in GC dose and remission of PMR. TCZ dose reduction or TCZ infusion spacing are good options to consider in TCZ withdrawal.

Effectiveness of Geniculate Artery Embolization for Chronic Pain after Total Knee Replacement-A Pilot Study.

PURPOSE: To evaluate the efficacy and safety of embolization of hyperemic synovial tissue for the treatment of persistent pain after total knee arthroplasty (TKA). MATERIALS AND METHODS: Twelve patients with persistent pain after TKA were enrolled in this prospective, single-center pilot study. Genicular artery embolization (GAE) was performed using 75-µm spherical particles. The patients were assessed using a 100-point Visual Analog Scale (VAS) and Knee Injury and Osteoarthritis Outcome Score (KOOS) at baseline and 3 and 6 months thereafter. Adverse events were recorded at all time points. RESULTS: A mean of 1.8 ± 0.8 abnormal hyperemic genicular arteries were identified and embolized, with a median volume of diluted embolic material of 4.3 mL in all 12 (100%) patients. The mean VAS score on walking improved from 73 ± 16 at baseline to 38 ± 35 at the 6-month follow-up (P < .05). The mean KOOS pain score improved from 43.6 ± 15.5 at baseline to 64.6 ± 27.1 at the 6-month follow-up (P < .05). At the 6-month follow-up, 55% and 73% of the patients attained a minimal clinically important change in pain and quality of life, respectively. Self-limited skin discoloration occurred in 5 (42%) patients. The VAS score increased by more than 20 immediately after embolization in 4 (30%) patients, who required analgesic treatment for 1 week. CONCLUSION: GAE is a safe method of treating persistent pain after TKA that demonstrates potential efficacy at 12 months.

Machine-learning derived algorithms for prediction of radiographic progression in early axial spondyloarthritis.

OBJECTIVES: To compare machine learning (ML) to traditional models to predict radiographic progression in patients with early axial spondyloarthritis (axSpA). METHODS: We carried out a prospective French multicentric DESIR cohort study with 5 years of follow-up that included patients with chronic back pain for <3 years, suggestive of axSpA. Radiographic progression was defined as progression at the spine (increase of at least 1 point of mSASSS scores/2 years) or at the sacroiliac joint (worsening of at least one grade of the mNY score between 2 visits). Statistical analyses were based on patients without any missing data regarding the outcome and variables of interest (295 patients).Traditional modelling: we performed a multivariate logistic regression model (M1); then variable selection with stepwise selection based on Akaike Information Criterion (stepAIC) method (M2), and Least Absolute Shrinkage and Selection Operator (LASSO) method (M3).ML modelling: using "SuperLearner" package on R, we modelled radiographic progression with stepAIC, LASSO, random forest, Discrete Bayesian Additive Regression Trees Samplers (DBARTS), Generalized Additive Models (GAM), multivariate adaptive polynomial spline regression (polymars), Recursive Partitioning And Regression Trees (RPART) and Super Learner. Accuracy of these models was compared based on their 10-fold cross-validated AUC (cv-AUC). RESULTS: 10-fold cv-AUC for traditional models were 0.79 and 0.78 for M2 and M3, respectively. The three best models in the ML algorithms were the GAM, the DBARTS and the Super Learner models, with 10-fold cv-AUC of: 0.77, 0.76 and 0.74, respectively. CONCLUSIONS: Two traditional models predicted radiographic progression as good as the eight ML models tested in this population.

The Association between Oxytocin and Lower Limb Osteoarthritis: A Prospective Cohort Study.

Oxytocin (OT), a neuropeptide best known for its role in emotional and social behaviors, has been linked to osteoarthritis (OA). This study aimed to investigate the serum OT level in hip and/or knee OA patients and to study its association with disease progression. Patients from the KHOALA cohort with symptomatic hip and/or knee OA (Kellgren and Lawrence (KL) scores of 2 and 3) and follow-up at 5 years were included in this analysis. The primary endpoint was structural radiological progression, which was defined as an increase of at least one KL point at 5 years. Logistic regression models were used to estimate the associations between OT levels and KL progression while controlling for gender, age, BMI, diabetes and leptin levels. Data from 174 hip OA patients and 332 knee OA patients were analyzed independently. No differences in OT levels were found between the 'progressors' and 'non-progressors' groups among the hip OA patients and knee OA patients, respectively. No statistically significant associations were found between the OT levels at baseline and KL progression at 5 years, the KL score at baseline or the clinical outcomes. Higher structural damage at baseline and severe structural progression of hip and knee osteoarthritis did not appear to be associated with a low serum OT level at baseline.

Management and outcome of native joint septic arthritis: a nationwide survey in French rheumatology departments, 2016-2017.

OBJECTIVES: To describe current management and outcome of native joint septic arthritis (NJSA) in French rheumatology departments. METHODS: For this retrospective, nationwide multicentric study, 127 French rheumatology departments were contacted to report up to 12 cases of NJSA that occurred between 1 January 2016 and 31 December 2017. Characteristics, diagnosis procedures, therapeutic management and outcome were recorded. RESULTS: Overall, 362 patients were included (mean age 64.0±18.6 years, median Charlson comorbidity index 3.5 (0-14)). Knee was the most frequent site (n=160 (38.9%)), and Staphylococcus sp (n=185 (51.4%)), the most frequent pathogen. All patients received antibiotics for a mean duration of 46.8 (±22.0) days, including intravenous route for a mean of 17.2 (±15.4) days. Management was heterogeneous. Surgical procedure was performed in 171 (48.3%), joint immobilisation in 128 (43.8%). During follow-up, 91 (28.3%) patients have had serious complications and 28 (9.2%) of them died. Factors associated with 1-year mortality were age (OR 1.08, 95% CI 1.04 to 1.13; p<0.001), Charlson's index (OR 1.30, 95% CI 1.06 to 1.58; p=0.012), presence of bacteraemia (OR 4.02, 95% CI 1.35 to 11.99; p=0.008), antibiotic use in the previous 3 months (OR 3.32, 95% CI 1.11 to 9.87; p=0.029) and Staphylococcus aureus NJSA compared with Streptococcus sp. NJSA (OR 7.24, 95% CI 1.26 to 41.68, p=0.027). The complete recovery with no adverse joint outcome at 1 year was observed in n=125/278 patients (55.0%). CONCLUSION: Prognosis of NJSA remained severe with a high rate of morbimortality. Its management was very heterogeneous. This study highlights the importance of the new French recommendations, published after the completion of the study, in order to facilitate NJSA management.

Socio-demographic determinants in the evolution of pain in inflammatory rheumatic diseases: results from ESPOIR and DESIR cohorts.

OBJECTIVE: To determine whether socio-demographic factors are associated with heterogeneity in pain evolution in inflammatory rheumatic diseases (IRDs) after accounting for disease-specific characteristics in a system with universal health care. METHODS: This analysis included the data from two prospective observational cohorts of early IRDs (ESPOIR for early RA and DESIR for early SpA). Data on pain was measured, respectively, on 13 and 9 occasions spanning 10 and 6 years of follow-up using the Short-Form 36 bodily pain score for 810 participants of ESPOIR, and 679 participants of DESIR. Linear mixed models were used to characterize differences in pain evolution as a function of age (tertiles), sex, ethnicity, education, marital, and professional status, after accounting for disease-related, treatment, lifestyle, and health factors. RESULTS: While transitioning from early (disease duration ≤6 months for RA and ≤3 years for SpA) to long-standing disease, differences in pain evolution emerged as a function of age (P < 0.001), sex (P = 0.050), and ethnicity (P = 0.001) in RA, and as a function of age (P = 0.048) in SpA; younger age, males, and Caucasians exhibited lower pain in the latter phases of both diseases. Highly educated participants (RA, ß = -3.8, P = 0.007; SpA, ß = -6.0, P < 0.001) for both diseases, and Caucasians (ß = -5.6, P = 0.021) for SpA presented with low pain early in the disease, with no changes throughout disease course. CONCLUSION: Being older, female, non-Caucasian and having lower education was found to be associated with worse pain in early and/or long-standing IRDs, despite universally accessible health-care. Early identification of at-risk populations and implementation of multidisciplinary strategies may reduce patient-reported health outcome disparities. TRIAL REGISTRATION REGISTRATIONS: ESPOIR: ClinicalTrials.gov, www.clinicaltrials.gov, NCT03666091. DESIR: ClinicalTrials.gov, www.clinicaltrials.gov, NCT01648907.

Fully automated opportunistic screening of vertebral fractures and osteoporosis on more than 150 000 routine computed tomography scans.

OBJECTIVE: Osteoporosis is underdiagnosed and undertreated, although severe complications of osteoporotic fractures, including vertebral fractures, are well known. This study sought to assess the feasibility and results of an opportunistic screening of vertebral fractures and osteoporosis in a large database of lumbar or abdominal CT scans. MATERIAL AND METHODS: Data were analysed from CT scans obtained in 35 hospitals from patients aged 60 years or older and stored in a Picture Archiving and Communication System in Assistance-Publique-Hôpitaux de Paris, from 2007 to 2013. Dedicated software was used to analyse the presence or absence of at least 1 vertebral fracture (VF), and the radiodensity of the lumbar vertebrae was measured Hounsfield Units (HUs). A simulated T-score was calculated. RESULTS: Data were analysed from 152 268 patients [mean age (S.D.) = 73.2 (9.07) years]. Success rates for VF assessment and HUs measurements were 82 and 87%, respectively. The prevalence of VFs was 24.5% and increased with age. Areas under the receiver operating characteristic curves for the detection of VFs were 0.61 and 0.62 for the mean HUs of the lumbar vertebrae and the L1 HUs, respectively. In patients without VFs, HUs decreased with age, similarly in males and females. The prevalence of osteoporosis (sT-score ≤ -2.5) was 23.8% and 36.5% in patients without and with VFs, respectively. CONCLUSION: It is feasible on a large scale to screen for VFs and osteoporosis during opportunistic screening in patients 60 years or older having lumbar or abdominal CT.

Costs of patient management over 18 months following a hip, clinical vertebral, distal forearm, or proximal humerus fragility fracture in France-results from the ICUROS study.

This observational study prospectively assessed direct and indirect costs related to patient management over 18 months following hip, clinical vertebral, humeral, or distal forearm fracture events in France. It appears that their levels were much higher than the previous estimates, raising the burden of osteoporosis-related fractures on public health expenditures. INTRODUCTION: This prospective observational study assessed the costs related to patient management over the 18-month period following the event of a hip, clinical vertebral, humeral, or distal forearm fracture in France. METHODS: Individuals aged ≥ 50 years old with the diagnosis of a fragility fracture in six French University Hospitals were enrolled in the International Costs and Utilities Related to Osteoporotic Fractures Study (ICUROS). All resources used over the defined period and related to fracture and the underlying osteoporosis management were collected by questionnaires at baseline, 4 months, 12 months, and 18 months. Information was collected by direct or phone contact completed by patients' records and interviews of partner, family, and general practitioners. Costs were estimated from a societal perspective, including direct and indirect costs. We implemented recursive partitioning analysis (RPA), a statistical learning algorithm to identify predictors of costs. RESULTS: Four hundred thirty-one patients (mean age 72.5 years; 84.6% women) were evaluated. Among them, 17.6% had a prior fracture in the last 5 years. Approximately half of the whole group lived alone in the community, and 56.8% were from a low- or middle-income category. Over the 18-month period of evaluation, total costs (including initial fracture-related and follow-up ones) were 23 926 €, 14 561 €, and 6 905 € for the hip, clinical vertebral, and distal forearm fracture, respectively. Over a year, costs related to a humeral fracture were 10 319 €. The RPA identified mobility impairment prior to fracture as a predictor of increase in costs related to fracture. CONCLUSIONS: Our study for the first time prospectively assessed total costs related to the four main osteoporotic fractures in France. It appears that their levels were much higher than previous estimates, raising the burden of osteoporosis-related fractures on public health expenditures.

Bone Involvement in Patients with Spondyloarthropathies.

Spondyloarthropathies (SpA) are common systemic inflammatory rheumatic diseases, in which, as in other rheumatic diseases, levels of markers of bone resorption are elevated, leading to bone loss and elevated risk of vertebral fractures. However, the diseases are also associated with new bone formation in the spine, the so-called syndesmophytes. We tried to unravel the pathogenesis of formation and growth of syndesmophytes and evaluated new diagnostic and treatment options. After a successful meeting of the Working Group on Rheumatic Diseases at the ECTS 2020, we (WL and CR) were excited about the quality of the speakers (CM, JH, AG, and GL) and their complimentary lectures. Given the relative lack of reviews on spondyloarthropathies and bone, we decided to work together on a comprehensive review that might be interesting for basic scientists and clinically relevant for clinicians. Radiographic progression in axSpA is linked to several risk factors, like male sex, smoking, HLA-B-27, increased levels of CRP, presence of syndesmophytes, and marked inflammation on MRI. The potential role of mechanical stress in the context of physically demanding jobs has been also suggested to promote structural damages. Different treatment options from NSAIDs to biologic agents like TNF inhibitors (TNFi) or IL-17inhibitors (IL-17i) result in a reduction of inflammation and symptoms. However, all these different treatment options failed to show clear and reproducible results on inhibition on syndesmophyte formation. The majority of data are available on TNFi, and some studies suggested an effect in subgroups of patients with ankylosing spondylitis. Less information is available on NSAIDs and IL-17i. Since IL-17i have been introduced quite recently, more studies are expected. IL-17 inhibitors (Il-17i) potently reduce signs and symptoms, but serum level of IL-17 is not elevated, therefore, IL-17 probably has mainly a local effect. The failure of anti-IL-23 in axSpA suggests that IL-17A production could be independent from IL-23. It may be upregulated by TNFα, resulting in lower expression of DKK1 and RANKL and an increase in osteogenesis. In active AS markers of bone resorption are increased, while bone formation markers can be increased or decreased. Bone Turnover markers and additional markers related to Wnt such as DKK1, sclerostin, and RANKL are valuable for elucidating bone metabolism on a group level and they are not (yet) able to predict individual patient outcomes. The gold standard for detection of structural lesions in clinical practice is the use of conventional radiographics. However, the resolution is low compared to the change over time and the interval for detecting changes are 2 years or more. Modern techniques offer substantial advantages such as the early detection of bone marrow edema with MRI, the fivefold increased detection rate of new or growing syndesmophytes with low-dose CT, and the decrease in 18F-fluoride uptake during treatment with TNFα-inhibitors (TNFi) in a pilot study in 12 AS patients. Detection of bone involvement by new techniques, such as low-dose CT, MRI and 18-Fluoride PET-scans, and bone turnover markers, in combination with focusing on high-risk groups such as patients with early disease, elevated CRP, syndesmophytes at baseline, male patients and patients with HLA-B27 + are promising options for the near future. However, for optimal prevention of formation of syndesmophytes we need more detailed insight in the pathogenesis of bone formation in axSpA and probably more targeted therapies.

Barriers and Expectations for Patients in Post-Osteoporotic Fracture Care in France: The EFFEL Study.

OBJECTIVES: This study aimed to quantify the relative importance of barriers to better secondary prevention of osteoporotic fractures and of care expectations expressed by patients with osteoporotic fractures in France. METHODS: A qualitative exploration of potential barriers to care and expectations was undertaken through a systematic literature review and in-depth patients interviews. A list of 21 barriers and 21 expectations was identified. These were presented to 324 subjects with osteoporotic fractures, identified in a representative sample of the French population, in the form of best-worst scaling questionnaires. Patients rated the relative importance of the attributes, and arithmetic mean importance scores were calculated and ranked. A Bayesian hierarchical model was also performed to generate a relative importance score. Latent class analysis was performed to identify potential subgroups of patients with different response profiles. RESULTS: A total of 7 barriers were rated as the most important, relating to awareness of osteoporosis and coordination of care. The highest-ranked barrier, "my fracture is not related to osteoporosis," was significantly more important than all the others (mean importance score 0.45; 95% confidence interval 0.33-0.56). A similar ranking of attributes was obtained with both the arithmetic and the Bayesian approach. For expectations, no clear hierarchy of attributes was identified. Latent class analysis discriminated 3 classes of respondents with significant differences in response profiles (the educated environmentalists, the unaware, and the victims of the system). CONCLUSIONS: Better quality of care of osteoporosis and effective secondary fracture prevention will require improvements in patient education, training of healthcare professionals, and coordination of care.

Adherence to and patient's knowledge of self-management of subcutaneous biologic therapy in chronic inflammatory rheumatic diseases: results of a multicentre cross-sectional study.

OBJECTIVES: Non-adherence to biologic therapy is an issue in chronic inflammatory rheumatic diseases (CIRDs) and might be related to poor patient knowledge of the risk of these therapies. Our aim here was to evaluate the level of patient adherence to and knowledge of self-care safety skills for biologic therapy. METHODS: This was a multicentre, cross-sectional study in which out-patients visited an office- or hospital-based rheumatologist. All the patients received subcutaneous biologic therapy for CIRDs. We collected data on: 1. the level of CIRD patient adherence to current subcutaneous biologic therapy using both the self-administered Compliance Questionnaire Rheumatology 5 items (CQR5) and a simple adherence question; 2. patients' knowledge of self-management of biologic therapy by the self-administered BIOSECURE questionnaire; 3. sources of information related to biologic therapy. RESULTS: In all, 285 patients (rheumatoid arthritis, n=103; spondyloarthritis, n=153; psoriatic arthritis, n=25) were enrolled by 19 rheumatologists. The mean (SD) biologic therapy duration was 5.9 (4.9) years. Adherence to the current biologic therapy was high (79.3% and 57.5% according to the CQR5 questionnaire and the adherence question, respectively). Level of knowledge of self-care safety skills (median BIOSECURE score 71) was in the acceptable range. Level of adherence and level of knowledge of self-care safety skills for biologic therapy were not associated. Patients declared that the main sources of information were their rheumatologist (92.6%) and the rheumatology team (30.5%). CONCLUSIONS: According to the patients' estimation, adherence to biologic therapy and the level of knowledge of self-care safety skills related to biologic therapy are acceptable, and these domains are not related (e.g. level of adherence and level of knowledge of risks).

Changes in bone formation regulator biomarkers in early axial spondyloarthritis.

OBJECTIVE: The hallmark of advanced axial SpA (axSpA) is spine ankylosis due to excessive ectopic bone formation. This prospective study aimed to describe the changes in serum levels of different regulators [sclerostin, dickkopf-1 (DKK-1)] and markers of bone formation [bone morphogenetic protein 7 (BMP-7)] over 5 years in early axSpA patients and to assess determinants of such changes. METHODS: The DEvenir des Spondyloarthropathies Indifférenciées Récentes cohort is a prospective, multicentre French study of 708 patients with early (>3 months-<3 years) inflammatory back pain suggestive of axSpA. Serum levels of BMP-7, sclerostin and DKK-1 were assessed at baseline and after 2 and 5 years. Changes in bone formation regulators over time were analysed using mixed linear models. RESULTS: Serum BMP-7 significantly increased over time, with a median relative change of 223.7% [interquartile range (IQR) 0-10 700 (0.17 pg/ml/month), P < 0.001]. Serum sclerostin significantly increased over time, with a median relative change of 14.8% [IQR -7.9-41.4% (0.001 ng/ml/month), P < 0.001]. Serum DKK-1 did not significantly change over time. Serum BMP-7 increased over time in active disease (Ankylosing Spondylitis Disease Activity Score with CRP ≥1.3, P = 0.01), but the increase was less pronounced with TNF inhibitor (TNFi) use (P < 0.001). No determinant was associated with serum sclerostin change. CONCLUSION: Serum BMP-7 change over 5 years was related with inflammation; it was increased in active disease, but the increase was low with TNFi use. Serum sclerostin levels significantly increased over time, but to a lesser degree than for serum BMP-7. CLINICAL TRIAL REGISTRATION: https://clinicaltrials.gov/, NCT01648907.

The Causes of Hypo- and Hyperphosphatemia in Humans.

Phosphate homeostasis involves several major organs that are the skeleton, the intestine, the kidney, and parathyroid glands. Major regulators of phosphate homeostasis are parathormone, fibroblast growth factor 23, 1,25-dihydroxyvitamin D, which respond to variations of serum phosphate levels and act to increase or decrease intestinal absorption and renal tubular reabsorption, through the modulation of expression of transcellular transporters at the intestinal and/or renal tubular level. Any acquired or genetic dysfunction in these major organs or regulators may induce hypo- or hyperphosphatemia. The causes of hypo- and hyperphosphatemia are numerous. This review develops the main causes of acquired and genetic hypo- and hyperphosphatemia.

Topographical analysis of structural lesions between dominant and non-dominant hands in erosive osteoarthritis.

KEY MESSAGES: No difference between both hands was observed for clinical and radiographical presentations in EHOA patients. A bilateral and symmetrical relationship was found between hand joints. HIGHLIGHTS: EHOA have symmetrical distribution and specific association in structural lesions. This study aims to analyse the preferential topographical distribution of clinical and structural lesions between the dominant and non-dominant hands in erosive hand osteoarthritis (EHOA) patients. Both hands were assessed via radiography in EHOA patients. A comparative analysis of the clinical features and structural lesions between the dominant and non-dominant hands was performed. The structural lesions were assessed according to the anatomical radiographic score of Verbruggen-Veys (VV). Next, a principal component analysis was performed to describe and highlight the relationships observed between the joints. Sixty patients were included in this study: there were 57 women, and the mean age was 66.1 (± 7.6) years. For the distal interphalangeal (DIP) joints, nodes were observed more frequently on the dominant hand (4 vs 3; p = 0.005). No difference in structural lesions was observed between the two hands except for the 2nd proximal interphalangeal (PIP) (p = 0.045). A principal component analysis with varimax rotation described relationships between the 2nd PIP, 3rd PIP, 4th PIP, 4th DIP and 5th DIP joints in both hands. No significant differences between dominant and non-dominant hands were observed for clinical and structural lesions in our sample of EHOA patients. A bilateral and symmetrical injury was observed in most EHOA joints. Trial registration Clinical trial registration number: NCT01068405.

Relationship between Oxytocin and Osteoarthritis: Hope or Despair?

Oxytocin (OT) is involved in breastfeeding and childbirth and appears to play a role in regulating the bone matrix. OT is synthesized in the supraoptic and paraventricular nuclei of the hypothalamus and is released in response to numerous stimuli. It also appears to be produced by osteoblasts in the bone marrow, acting as a paracrine-autocrine regulator of bone formation. Osteoarthritis (OA) is a disease of the whole joint. Different tissues involved in OA express OT receptors (OTRs), such as chondrocytes and osteoblasts. This hormone, which levels are reduced in patients with OA, appears to have a stimulatory effect on chondrogenesis. OT involvement in bone biology could occur at both the osteoblast and chondrocyte levels. The relationships between metabolic syndrome, body weight, and OA are well documented, and the possible effects of OT on different parameters of metabolic syndrome, such as diabetes and body weight, are important. In addition, the effects of OT on adipokines and inflammation are also discussed, especially since recent data have shown that low-grade inflammation is also associated with OA. Furthermore, OT also appears to mediate endogenous analgesia in animal and human studies. These observations provide support for the possible interest of OT in OA and its potential therapeutic treatment.

Non-acidic activation of pain-related Acid-Sensing Ion Channel 3 by lipids.

Extracellular pH variations are seen as the principal endogenous signal that triggers activation of Acid-Sensing Ion Channels (ASICs), which are basically considered as proton sensors, and are involved in various processes associated with tissue acidification. Here, we show that human painful inflammatory exudates, displaying non-acidic pH, induce a slow constitutive activation of human ASIC3 channels. This effect is largely driven by lipids, and we identify lysophosphatidylcholine (LPC) and arachidonic acid (AA) as endogenous activators of ASIC3 in the absence of any extracellular acidification. The combination of LPC and AA evokes robust depolarizing current in DRG neurons at physiological pH 7.4, increases nociceptive C-fiber firing, and induces pain behavior in rats, effects that are all prevented by ASIC3 blockers. Lipid-induced pain is also significantly reduced in ASIC3 knockout mice. These findings open new perspectives on the roles of ASIC3 in the absence of tissue pH variation, as well as on the contribution of those channels to lipid-mediated signaling.