[Treatment of adult chronic non-bacterial osteitis in Germany : Comparison of real-world practice and current expert consensus recommendations].

The non-interventional observational study employed both retrospective and prospective approaches to analyze the treatment reality of 114 patients with adult chronic non-bacterial osteitis (CNO) at three German university centers over the period 1985-2025. The primary objective was to characterize treatment courses among adult CNO patients in Germany for and to compare these with the international consensus recommendations published in 2024. According to these recommendations, nonsteroidal anti-inflammatory drugs (NSAIDs) are preferred as first-line therapies, whereas tumor necrosis factor inhibitors (TNFi) or bisphosphonates are advised as second-line options.The results indicate that although 61% of patients initially received NSAIDs, only 20% were treated at the recommended first-line dosage. In contrast, 46% of patients received conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) as first-line therapy. Owing to their limited efficacy, csDMARDs are currently recommended only in selected cases with overlapping features of adult CNO and either axial spondyloarthritis (axSpA) or psoriatic arthritis (PsA). Our data demonstrate that overlap was present in 70% of the adult CNO cohort. As recommended, TNFi were the predominant second-line therapy (n = 32/86; 37%), whereas bisphosphonates were administered to only one patient.The observed therapeutic response, assessed by the rate of treatment discontinuation within 12 months, reached a maximum of 53%. These findings underscore the importance of current consensus recommendations in standardizing terminology and optimizing treatment strategies for CNO. However, the lack of a dedicated ICD-10 code and the absence of regulatory approval for the recommended therapeutic agents in Germany remain unresolved challenges.