Background Chronic recurrent multifocal osteomyelitis (CRMO) is a rare autoinflammatory disorder that has sterile bone inflammation as a main phenotypic feature. Diagnosis of CRMO is based on typical clinical and radiologic findings and presence of some inflammatory markers. Plain radiographs, technetium bone scan and MRI may be used for diagnosis of children with suspected CRMO. Despite data for other imaging methods in chidren with CRMO, little information is available regarding the bone mineral density.

Objectives The aim of the study was to evaluate bone mineral density (BMD) findings in children with CRMO at time of diagnosis.

Methods The medical records of children with CRMO were reviewed retrospectively. Children who met Bristol diagnostic criteria were included in the study. Clinical and laboratory findings, bone scan and MRI features were analyzed. Bone mineral density was measured by DEXA technique at femoral neck and lumbar spine regions; a Z-score$<-$2 was considered as osteoporosis.

Results A total of 6 patients, one girl and 5 boys, with a median age of 10 years (4 – 14 years) and a median follow-up period of 38.5 months (3 – 72 months) were included in the study. MRI and whole body technetium bone scan were performed at 6 and 4 children, respectively and detected at least two lesions MRI or bone scans. Osteoporosis was detected in 5 patients at diagnosis. Bone mineral density Z-scores were median -2.9 [-4.9±(-2,4)] and -2.9 [-4,1 – (-1,8)] at femoral neck and lumbar spine, respectively.

Conclusions Osteoporosis is common in children with CRMO, it may be related with disease spectrum. Evaluation of bone mineral density abnormalities at time of diagnosis and during therapy may be a part of primary care in children with CRMO.

Disclosure of Interest None declared