Bone Abstracts

Objectives: Juvenile idiopathic arthritis (JIA) – is a chronic inflammatory disease of joints which can affect optimal linear growth, risk of fractures and bone quality during the childhood and adult life. The aim of our study was to detect the simple clinical and laboratorial markers which can predict the realization of low bone mineral density (LBMD <−2 S.D.) in children with JIA.

Methods: 198 children (82 boys and 116 girls) with JIA were included in our study. For assessment of JIA activity we used onset age, duration of morning stiffness, number of active joints, white blood cells (WBC) count, Westergren erythrocyte sedimentation rate (ESR), C-reactive protein. Physician global assessment (PGA) of disease activity, measured on a 10-cm visual analog scale (VAS) where 0=no activity and 10=maximum activity; parent/patient global assessment of well-being, measured on a 10-cm VAS where 0=very well and 10=very poor. We utilized combined indexes for assessment disease activity – DAS28, JADAS71, CDAI.

Bone mineral density (BMD) was measured by lumbar spine (L1–L4) DXA with pediatric reference database. Osteocalcin, CTX, parathyroid hormone, total and ionized calcium, inorganic phosphate, total alkaline phosphatase activity was utilized for assessment of bone metabolism.

Results: Low weight and linear growth (<10 and 25%), BMI <16.6, MD VAS >5.0, DAS >2.9, DAS28 >4.2, JADAS 10>15.6, JADAS 27>15.1, CDAI >18.1, Steinbrocker’s functional class >2, systemic arthritis, corticosteroid treatment, arthritis duration >4.5 years, number of active joints >5, number of painful joints >9, morning stiffness >90 min, parental overall JIA activity (VAS) >5.8, ESR >16 mm/h, CRP >22.6 mg/l increased the risk of LBMD in JIA children. Among metabolic markers Ca total ≤2.42 mmol/l and Pi >1.59 mmol/l also increased the possibility of LBMD.

Conclusion: Our data can help in identification the group of risk of JIA patients with LBMD and suggest the indications for densitometry evaluation of JIA children.

Disclosure: The authors declared no competing interests.