Assessment of disease activity using a whole-body MRI derived radiological activity index in chronic nonbacterial osteomyelitis

Abstract

Background Based on the recently developed ChRonic nonbacterial Osteomyelitis MRI Scoring tool (CROMRIS), we developed a radiological activity index (RAI-CROMRIS) to obtain a quantification of the overall bone involvement in individual patients. Methods Whole Body Magnetic Resonance Imaging (WB-MRI) images were scored according to parameters included in the RAI-CROMRIS: bone marrow hyperintensity, signal extension, soft tissue/periosteal hyperintensity, bony expansion, vertebral collapse. These parameters were evaluated for each bone unit yielding a score from 0 to 7 and summed up as RAI-CROMRIS including all bone units. We assessed clinical disease activity using a physician global assessment (PGA) and radiological findings in 76 treatment-naïve patients; 46 of 76 were evaluated at 6 and 12 months after initial WB-MRI. Quantitative variables were compared using the Mann-Whitney U test for unmatched groups and the Wilcoxon signed-rank test for paired groups. Correlation was evaluated using Spearman’s rank coefficient (rs). Results There was a significant correlation between RAI-CROMRIS and PGA (rs = 0.32; p = 0.0055), between RAI-CROMRIS and presence of elevated erythrocyte sedimentation rate (p = 0.013) and C-reactive protein (p = 0.0001) at baseline. The RAI-CROMRIS decreased from a median of 17 at baseline to 12 at 6 months (p = 0.004) and remained stable (median 11) at 12 months. A correlation between the RAI-CROMRIS and the PGA was observed at baseline (rs = 0.41; p = 0.004) and during follow up at 6 months (rs = 0.33; p = 0.025) and 12 months (rs = 0.38; p = 0.010). The baseline RAI-CROMRIS (median 20) was significantly higher in patients who subsequently received bisphosphonates than in patients who received other treatments (median 12) and decreased significantly after bisphosphonates (p = 0.008). Conclusions The RAI-CROMRIS was correlated with clinical and laboratory measures of disease activity showing significant short-term changes following treatment with bisphosphonates. This tool could be used in clinical practice and clinical trials after validation.

Update on treatment responses and outcome measure development in chronic nonbacterial osteomyelitis

“…Each bone is scored on a scale based on presence or absence of imaging findings pertaining to CNO. There was a significant association of the RAI-CROMRIS with disease activity parameters, including the physician global assessment, presence of functional impairment, and increased inflammatory markers in patients at baseline, suggesting that the burden of radiological activity, as measured by the RAI-CROMRIS, reflects the overall degree of clinical activity of each individual patient [60 ▪ ]…”

Updates zur chronisch nichtbakteriellen Osteomyelitis (CNO)

“…Beide Scores beinhalten Größe von Knochenläsionen, Knochenödem, Bindewegebsauffälligkeiten und vertebrale Veränderungen zur Bewertung der Krankheitsaktivität 67 . Beide Scores sollen eine standardisierte Interpretation für Knochenläsionen ermöglichen, ihre Verwendbarkeit in der Routineversorgung ist jedoch begrenzt.…”

Feasibility of Conducting Comparative Effectiveness Research and Validation of a Clinical Disease Activity Score for Chronic Nonbacterial Osteomyelitis

“…Furthermore, the CHAQ includes many assessments of upper extremity function that are less useful for CNO which primarily affects the lower extremities. MRI scoring tools have been developed (15,19,20), but the clinical significance of asymptomatic MRI lesions remains unknown and the weighting of lesions at different sites has not been systematically identified. Thus, a clinical disease activity assessment tool that is independent of MRI is urgently needed for the assessment of therapies.…”

“…Historically, pain has been used as a surrogate for response to therapy, but this approach is limited due to secondary amplified pain syndrome that can occur in CNO. Magnetic resonance imaging (MRI) can provide detailed information of CNO lesions (14)(15)(16)(17)(18)(19)(20) and is used often to evaluate the disease burden for children with CNO at the time of diagnosis. Although whole body MRI (WBMRI) and regional MRI are clinically useful, patients can have asymptomatic lesions in locations not considered at high risk for permanent bone damage, and whether these lesions require treatment is uncertain.…”

“…It remains unclear whether all asymptomatic lesions require treatment. Several MRI scoring tools have been developed (18,22,23), but the weighting of lesions at different sites has not been systematically identified. In 2010, Beck et al (24) developed a core set of CNO outcome variables, PedCNO.…”