Lost bones: differential diagnosis of acro-osteolysis seen by the pediatric rheumatologist.

INTRODUCTION: Acro-osteolysis is a radiographic finding which refers to bone resorption of the distal phalanges. Acro-osteolysis is associated with various conditions and its presence should prompt the clinician to search for the underlying etiology. The aim of this review is to discuss disorders with which acro-osteolysis is associated and their distinguishing features, with a focus on the pediatric population. METHODS: A targeted literature review was performed using the term "acro-osteolysis" in combination with other key terms. The primary search results were supplemented using reference citations. Articles published prior to the year 2000 were included if they described additional associations not encountered in the more recent literature. RESULTS: Genetic disorders (particularly primary hypertrophic osteoarthropathy and skeletal dysplasias) and rheumatic diseases (particularly psoriatic arthritis and systemic sclerosis) are the most frequently encountered conditions associated with acro-osteolysis in children. Hyperparathyroidism, neuropathy, local trauma and thermal injury, and spinal dysraphism should also be included in the differential diagnosis. CONCLUSION: Although acro-osteolysis is uncommon, its presence should prompt the clinician to consider a differential diagnosis based on clinical and radiographic features.

Hallmark trials in ANCA-associated vasculitis (AAV) for the pediatric rheumatologist.

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) refers to a complex group of systemic vasculitides that are characterized by primary small-to-medium sized blood vessel inflammation with the presence of autoantibodies known as ANCA. AAV diseases include Granulomatosis with Polyangiitis (GPA), Eosinophilic Granulomatosis with Polyangiitis (EGPA), and Microscopic Polyangiitis (MPA). AAVs are challenging conditions associated with high cumulative disease and treatment related morbidity and mortality. Given its rarity and the resulting paucity of pediatric-specific clinical trial evidence, pediatric rheumatologists have had to often extrapolate from adult literature for management and therapeutic decisions. The aim of this review is to provide a comprehensive overview of the important findings and overall conclusions of critical landmark clinical trials in the induction and maintenance treatments in adult AAV for the pediatric rheumatologist. This review also highlights the outcomes of recent pediatric AAV observational studies and discusses the future research priorities in pediatric AAV management.

Proposed Core Set of Items for Measuring Disease Activity in Systemic Juvenile Idiopathic Arthritis.

OBJECTIVE: To date, there are no standardized disease activity tools for systemic juvenile idiopathic arthritis (sJIA). We developed a core set of disease activity measures for sJIA. METHODS: We conducted a validation study in patients with sJIA recruited from 3 Canadian institutions. Disease activity scores were based on questionnaires, clinical factors, and laboratory measures. The physician's global assessment was our criterion standard. We determined the strength of association of each item with the criterion standard. We then surveyed international experts to determine the top 10 items. Finally, we used the experts' responses to generate a proposed core set of disease activity measures. RESULTS: We enrolled 57 subjects - 26 with moderately or severely active disease, and 31 with mildly active or inactive disease. Items that most strongly correlated with the criterion standard were number of active joints (r = 0.79), parent's global assessment of disease activity (r = 0.53), erythrocyte sedimentation rate (ESR; r = 0.62), and C-reactive protein (CRP; r = 0.61). The response rate from international experts was 82% (154/187). Items with the most votes, in descending order, were number of active joints, number of days with fever in the preceding 2 weeks, patient's and parent's global assessments of disease activity, sJIA rash, ESR, CRP, and hemoglobin level. CONCLUSION: We propose a core set of items for measuring disease activity in sJIA. Future research should be aimed at further validation of this core set in the international context.

Validity of the Stage of Exercise Scale in Children with Rheumatologic Conditions.

OBJECTIVE: To determine the face, content, and construct validity of the Stages of Exercise Scale (SOES) in children with rheumatologic conditions [juvenile idiopathic arthritis (JIA) and juvenile dermatomyositis (JDM)], and if the validity of the SOES differs by disease type by comparing it with a disease control with a chronic respiratory illness [cystic fibrosis (CF)]. METHODS: Sixty-seven children and adolescents (43 female) ages 11 to 18 years with a diagnosis of either JDM (n = 15), JIA (n = 39), or CF (n = 13) completed the SOES; scales of sensibility, process of change, decisional balance, and self-efficacy; the Child Health Assessment Questionnaire; and patient/physician ratings of disease severity. Physical activity was measured by an accelerometer. Relationships among SOES and measured constructs were determined by ANOVA and with logistical modeling. RESULTS: SOES, decisional balance, and self-efficacy as well as behavioral and cognitive processes from the process of change demonstrated significant differences across the staging subgroups. Disease groups did not significantly differ on the scoring across the SOES. Children and adolescents in higher stages participated in more minutes of vigorous physical activity compared with those in the lower stages. CONCLUSION: The SOES demonstrated good face, content, and construct validity in children and adolescents with rheumatic disease.

The relationship between physical activity levels and pain in children with juvenile idiopathic arthritis.

OBJECTIVE: Pain and reduced physical activity levels are common in children with juvenile idiopathic arthritis (JIA). Currently, there is no consensus about the role of physical activity in managing pain in JIA. The purpose of our study was to assess the relationship between physical activity level and pain in children ages 11 to 18 years with JIA. METHODS: A random sample of 50 patients with JIA were approached by mailed questionnaires. Physical activity was determined using the Physical Activity Questionnaire (PAQ). Pain measures included the Numerical Rating Scale (pain severity), SUPER-KIDZ body diagram (number of painful areas), and the Child Activities Limitations Inventory-21 (pain interference). Generalized linear models were used to assess the relationship between physical activity and pain, as well as the roles of sex and age. RESULTS: The response rate was 84%. Thirty-four respondents completed the questionnaire package. The median age was 15 years. The mean PAQ score was 2.16/5. Physical activity declines with increasing age in youth with JIA (r = 0.53, p = 0.0014). Lower physical activity is associated with greater pain interference (r = 0.39, p = 0.0217) and more severe pain (r = 0.35, p = 0.0422). CONCLUSION: Children with JIA report significantly less activity than healthy children based on PAQ scores, with physical activity declining throughout adolescence. Physical activity is inversely related to pain interference and severity in children with JIA. Our findings suggest that physical activity interventions may play an important role in the management of pain in JIA.