May 2026 Research Update

This month added a clearer picture that more than one anti-inflammatory approach can line up with symptom relief in children who have CNO/CRMO or very similar bone inflammation. The strongest new human data came from a single-center group treated with intravenous neridronate, where most children were classified as having at least a partial response and some had fewer bone lesions on whole-body MRI after treatment. Two single-patient reports also described meaningful improvement, one with naproxen for CRMO and one with tocilizumab for a CRMO-like picture in a different autoinflammatory disease. [1] [2] [3]

In 27 children treated with neridronate (a bisphosphonate medicine often used for bone conditions), 21 of 27 were reported as responders, including 6 complete responses and 15 partial responses. Inflammation in blood tests showed mixed movement, with ESR dropping while CRP did not clearly change in this group. In the subset with repeat MRI scoring available, bone lesion counts went down for those receiving neridronate alone, while they did not change in those also receiving other anti-inflammatory drugs, which makes it harder to separate which medicine drove which effect. [1]

Safety reporting in the neridronate group mainly involved short-term infusion-related effects, including acute phase reactions after the first infusion and mild, temporary low calcium levels, with one transient low neutrophil count reported. In the CRMO clavicle case, naproxen was followed by substantial pain relief and the child remained symptom-free at 6 months, with no side effects described. In the genetic autoinflammatory case (mevalonate kinase deficiency) with CNO-like bone lesions, tocilizumab (an IL-6 blocker) was followed by rapid improvement and year-long stability with only one mild flare reported. [1] [2] [3]

For patients and caregivers, this month mainly adds practical context about what has been reported to help pain and bone inflammation, rather than providing definitive answers about which option works best. The neridronate findings come from a small retrospective cohort (so it reflects real-world experience but cannot prove cause and effect), and the naproxen and tocilizumab reports are single patients (so they may not apply broadly). Still, together these studies help clarify that improvement can be tracked in more than one way, including day-to-day pain and function plus whole-body MRI lesion burden, and that responses may differ depending on the situation (such as early treatment timing or whether spine involvement is present). What remains uncertain is how these approaches compare head-to-head, and which patients are most likely to respond to each option. [1] [2] [3]

This month strengthened the idea that some simple lab measures might relate to how active CRMO is, but in a more specific way than standard inflammation tests. In one pediatric study, vitamin D levels were lower in children with CRMO than in matched healthy peers, and lower levels went along with higher clinical disease activity and a higher number of lesions on whole-body MRI. At the same time, vitamin D did not track with common inflammation markers like CRP or ESR in this dataset, suggesting it may reflect a different aspect of the condition than routine blood inflammation tests. [4]

The study compared 31 children with CRMO to 31 healthy controls and reported a higher frequency of vitamin D deficiency in the CRMO group. Within the CRMO group, lower vitamin D was linked with higher scores on a clinical activity measure and more MRI-detected skeletal lesions. The authors also reported that vitamin D deficiency remained independently linked with having CRMO in their statistical model, but the study design cannot show whether low vitamin D is a cause, a result, or simply a parallel finding. [4]

For families, this is most useful as a research update about monitoring and understanding disease activity, not as a proven way to predict flares or guide treatment choices. The finding that vitamin D levels lined up with symptom activity and MRI lesion burden may matter in the future if confirmed in larger, forward-looking studies, because it could offer an additional piece of information alongside imaging and symptoms. What remains uncertain is whether changing vitamin D levels would change CRMO activity, since this study only measured levels and did not test vitamin D as a treatment. [4]

This month reinforced that CRMO is usually approached as a whole-body condition where imaging and follow-up matter, even when symptoms seem focused in one place. A German pediatric consensus document highlighted whole-body MRI as a central tool for diagnosis and for monitoring over time, and it laid out a stepwise set of treatment and follow-up concepts. A separate clavicle case report showed how doctors sometimes combine whole-body MRI with a bone biopsy to support the diagnosis when a single bone lesion could otherwise look like something else. [5] [2]

In the guideline document, whole-body skeletal imaging (usually MRI) was presented as part of the diagnostic workup, and long-term follow-up after stopping treatment was recommended. The paper also described a general treatment ladder that starts with NSAIDs and may escalate to other immune-targeting medicines or bisphosphonates, with rapid escalation discussed for vertebral involvement. Because this is consensus-based and evidence levels were described as low to moderate, it summarizes current practice thinking rather than proving which approach is best for every child. [5]

In the clavicle case, whole-body MRI supported that the lesion looked like CRMO rather than an aggressive bone process, and a biopsy reported inflammatory changes without infection or cancer. After naproxen, the child had substantial pain relief and improved shoulder function and remained symptom-free for 6 months, which illustrates how symptom improvement can follow once CRMO is recognized and treated. As a single case, it mainly serves as an example of the diagnostic pathway and short-term outcome rather than a general prediction. [2]

For patients and caregivers, this section mostly clarifies what to expect from the diagnostic and monitoring process, rather than introducing a new test that is ready to replace current practice. The guideline and the case both point to whole-body MRI as important for seeing the full extent of bone involvement and for tracking changes over time, which can matter when symptoms do not match the number or location of lesions. What remains uncertain is how often biopsy is needed, since the case shows one reason it may be used (to rule out other causes), but guidelines and practice can vary by situation and center. [5] [2]