Standardized reporting and quantification of whole-body MRI findings in children with chronic non-bacterial osteomyelitis treated with pamidronate

Abstract

Objectives The objectives were to assess changes in radiological disease activity in children with chronic non-bacterial osteomyelitis (CNO) receiving pamidronate therapy and to test a modified radiological index for non-bacterial osteitis (mRINBO) in CNO. mRINBO was used for standardized reporting and quantification of whole-body MRI (WBMRI) findings resulting in an individual summary patient score. Methods WBMRI was retrospectively assessed in 18 children with CNO at baseline and after receiving pamidronate therapy for one year. Parameters of interest were: number and anatomic site of radiologically active bone lesions (RAL), size of RAL, extramedullary affection, spinal involvement and changes in mRINBO, which includes both the number and maximal size of RAL (RALmax) in addition to extramedullary and chronic changes. Results At the time of diagnosis, the mean age of the children was 9.8 (sd, 8.7–10.9) years and 11/18 were females. The number of RALs per patient decreased from median [interquartile range] 4.5 [3–8] to 3 [2–5] RALs per patient (p = 0.02) and extramedullary inflammatory changes regressed. Sixty-one percent of all RALs occurring at baseline resolved and three children became without active inflammatory lesions by WBMRI. The median size of RALs did not change when taking new lesions occurring in 7/18 children into account, but RALmax decreased significantly from 39 [29–45] mm at baseline to 28 [20–40] mm (p < 0.01) at year-one with a concomitant decrease of mRINBO from a median of 5 [4–7] to 4 [3–5] (p = 0.05). Conclusions Pamidronate therapy resulted in a decrease of mRINBO from baseline to year one. mRINBO may be a potential scoring method to quantify changes in radiological disease activity in children with CNO. However, further studies are needed to test feasibility and validity of mRINBO.

Chronic non-bacterial osteomyelitis (CNO) and chronic recurrent multifocal osteomyelitis (CRMO) with a focus on pamidronate therapy

“…The maximal index value is 10. Recently, the modified RINBO (mRINBO) index assessing CNO/CRMO patients treated with pamidronate was published by Andreasen et al, showing its clinical utility 32 .…”

“…Thus, mRINBO might be a potential scoring method to quantify changes in radiological disease activity. However, testing of the feasibility and validity of mRIN-BO is needed 32 . Recently, Reiser et al suggested that a combination of improvement in physician global disease activity (PGDA), patient-reported overall well-being and imaging-defined disease activity measures might document the inactivity of CNO disease 43 .…”

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

“…The data shown for bisphosphonates in Table 1[37 ▪▪ ,38 ▪ ,39,40,41 ▪ ,42 ▪ ,43 ▪ ,44,45,46,47 ▪▪ ] and TNFi in Table 2[37 ▪▪ ,38 ▪ ,39,40,41 ▪ ,42 ▪ ,43 ▪ ,44,45,47 ▪▪ ,48 ▪ ] demonstrates the difficulty of comparing retrospective outcome studies. The dosing regimens were different, and some studies used clinical outcomes measures while others reported imaging outcomes.…”

“…Standard protocols have been established and include short tau inversion recovery (STIR) or fat saturation sequences of coronal views of the whole body, the sagittal view of total spine and feet, and an axial view of the pelvis and knees [56 ▪ ,57,58 ▪ ]. Several groups have developed detailed CNO MRI scoring tools including bone marrow ‘edema’ (hyperintensity on STIR), soft tissue inflammation, hyperostosis (bony expansion), vertebral compression, and growth plate damage all showing sensitivity to change [36,47 ▪▪ ,57,59]. Further, an international group of pediatric radiologists and rheumatologists developed the CROMRIS (ChRonic nonbacterial Osteomyelitis MRI Scoring) tool through a consensus on grading CNO-specific MRI findings and on describing bone units based on anatomy [57].…”

Die Chronisch Nichtbakterielle Osteomyelitis (CNO) im Kindes- und Jugendalter

“…In den letzten Jahren wurden verschiedene bildgebende Instrumente (RINBO, CROMRIS) zur Unterstützung der Diagnosestellung beschrieben [53][54][55]. Hierbei wurden folgende Merkmale in der GK-MRT-Befundung herangezogen: Ausmaß der Knochenödeme und Weichteilentzündungen, Bewertung der Periostreaktion, Hyperostose, Wachstumsschädigung und Wirbelkompression [54][55][56]. Eine Validierung dieser radiologischen Diagnostiksysteme ist bisher nicht erfolgt.…”