Bone mineral density and turnover in non-corticosteroid treated African American children with juvenile rheumatoid arthritis

Objective. To determine bone mineral content (BMC), bone mineral density (BMD), Z scores, and markers of bone turnover in African American children with juvenile rheumatoid arthritis (JRA). Methods. Eight children with JRA with no prior exposure to corticosteroids were evaluated. Lumbar spine (L1-L4) and total body and total hip BMC and BMD were determined using dual x-ray absorptiometry (DXA), and Z scores (BMD) were calculated. Serum samples and markers of bone turnover including pyridinoline (PYR), N-terminal propeptide of type 1 procollagen (PLNP), osteocalcin (OC), and bone-specific alkaline phosphatase (BSAP) were measured. Results. The mean Z score (BMD) at the lumbar spine (L1-L4) in patients with JRA was -1.2 ± 0.8. Z scores for total body and total hip were within 1 standard deviation of normal compared with healthy historical controls matched for age, sex, and race. Conclusion. BMD was normal for chronological age (defined as Z score ≥ 2.0) in African American children with JRA who had not previously been treated with corticosteroids. Further studies are needed on the effects of JRA on skeletal health in African American children.