Association Between Serum Vitamin D Levels, Clinical Disease Activity and Magnetic Resonance Imaging Lesion Burden in Pediatric Chronic Recurrent Multifocal Osteomyelitis.

BACKGROUND

Chronic recurrent multifocal osteomyelitis is a rare autoinflammatory bone disorder in children. Vitamin D regulates immune and inflammatory pathways, but its impact on chronic recurrent multifocal osteomyelitis remains unclear. This study investigated the relationship between serum 25-hydroxyvitamin D levels and clinical, laboratory, and radiological characteristics of pediatric chronic recurrent multifocal osteomyelitis.

METHODS

Pediatric chronic recurrent multifocal osteomyelitis patients and age- and sex-matched healthy controls were retrospectively evaluated. Serum 25-hydroxyvitamin D, inflammatory markers, clinical disease activity score, and whole-body magnetic resonance imaging findings were analyzed.

RESULTS

Thirty-one chronic recurrent multifocal osteomyelitis patients and 31 controls were included. Chronic recurrent multifocal osteomyelitis patients had significantly lower 25-hydroxyvitamin D levels and a higher frequency of vitamin D deficiency (p<0.001). Serum 25-hydroxyvitamin D levels showed no correlation with C-reactive protein, erythrocyte sedimentation rate, or the neutrophil-to-lymphocyte ratio, but were inversely correlated with the clinical disease activity score (r=- 0.429 and p=0.020) and the number of magnetic resonance imaging-detected skeletal lesions (r=- 0.376 and p=0.044). Logistic regression confirmed vitamin D deficiency as independently associated with chronic recurrent multifocal osteomyelitis (odds ratio=0.59, 95% confidence interva: 0.41-0.88, and p=0.007).

CONCLUSIONS

Vitamin D deficiency is highly prevalent in pediatric chronic recurrent multifocal osteomyelitis and correlates with disease severity, reflected by clinical activity and lesion burden, independent of systemic inflammation. These findings suggest vitamin D as a potential biomarker in chronic recurrent multifocal osteomyelitis and highlight the need for prospective studies assessing its therapeutic role.