TOPLINE:

In France, inflammatory bowel disease (IBD)-associated chronic non-bacterial osteomyelitis (CNO) was a rare paediatric condition, with an estimated incidence of 0.12%; it typically presented with chronic bone pain mainly affecting the lower limbs and pelvis, and most patients achieved remission with anti-TNF-alpha therapy.

METHODOLOGY:

• Researchers aimed to describe a national paediatric cohort with coexisting IBD and CNO and to estimate the incidence of this association.
• They retrospectively collected all reported cases of the IBD-CNO association from French paediatric gastroenterology and rheumatology centres (2000-2024), and the incidence of IBD-CNO was estimated using data from the EPIMAD registry.
• A total of 37 children diagnosed with IBD-CNO (median age at diagnosis, 13.5 years; 20 boys) between 2011 and 2024 were included.
• Inflammation was assessed using standard laboratory markers (C-reactive protein levels and/or erythrocyte sedimentation rates), and CNO was identified on whole‑body MRI on the basis of findings consistent with inflammatory bone disease.
• Remission and relapse were assessed over a median follow‑up duration of 3 years.

TAKEAWAY:

• The estimated incidence of IBD-CNO in France was 0.12%, corresponding to approximately one case per 20,000 patient-years.
• IBD and CNO were diagnosed simultaneously in 35.1% of patients; CNO preceded IBD in 29.7%, and IBD preceded CNO in 35.1%, with a median interval of 1 year between diagnoses. Crohn's disease was the predominant IBD subtype (67.6%).
• Patients had a median of eight bone lesion localisations, with 55.2% of lesions involving the lower limbs and 20.0% involving the pelvis; dermatologic manifestations were reported in 37.8% of patients.
• At the end of follow-up, 75.7% of patients achieved remission, whereas 24.3% experienced relapse. Anti-TNF-alpha therapy was used in 73.0% of patients and was associated with higher rates of remission vs relapse (82.1% vs 44.4%; P = .041).

IN PRACTICE:

"CNO is a rare but possible association with pediatric IBD and should be considered in cases of osteoarticular pain after excluding more common peripheral arthritis," the authors wrote. "Multidisciplinary care management is recommended, involving gastroenterologists, rheumatologists, and dermatologists," they added.

SOURCE:

This study was led by Valérie Bertrand, Hôpital Jacques Monod, Le Havre, France. It was published online on June 16, 2026, in the Journal of Pediatric Gastroenterology and Nutrition.

LIMITATIONS:

The study had a retrospective design, which made it difficult to determine whether these lesions were paradoxical reactions or extraosseous manifestations. Additionally, because clinicians only recently recognised this disease in the 1990s, some cases likely went undiagnosed — particularly before the 2010s — potentially leading to an underestimation of its true incidence.

DISCLOSURES:

The study did not receive any specific funding. The authors declared having no conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.