Painful swelling of the anterior chest wall caused by osteitis and hyperostosis in the sternocostoclavicular region are characteristically observed in patients suffering from SAPHO syndrome. Autoimmune triggering of inflammation and bacterial infection is hypothesized to be involved in the pathogenesis. Promising treatment modalities include antirheumatic and antibiotic medications.
Ten patients with SAPHO syndrome and symptomatic osteitis in the sternocostoclavicular region were treated by a single instillation of glucocorticosteroids (20 mg triamcinolone) into the sternocostoclavicular joints. The disease activity was evaluated on the basis of a questionnaire asking for osteitis activity (quantified for complains on a scale of 0-6), by Health Assessment Questionnaire (HAQ) score, erythrocyte sedimentation rate, C-reactive protein, and magnet resonance imaging (MRI) scanning of the sternocostoclavicular region (osteitis scores quantified for inflammation on a scale of 0-2 by the radiologist) prior to injection and after 12 weeks. No changes of the preexisting antirheumatic therapy were allowed during the observation interval.
All patients continued the study during the follow-up. The osteitis score changed from 4.2 (mean; standard error (SE) ±0.3) to 3.2 (±0.4), [P = 0.062], the erythrocyte sedimentation rate from 19.0 (range from 12 to 30) to 19.9 (from 12 to 27), [P = 0.430], and the MRI score from 1.6 (±0.2) to 1.5 (±0.2) [P = 1.0]. One patient developed an increase of the clinical osteitis activity from 3 to 5 according the scoring system; only 2 patients showed a reduction of the MRI activity score from 2 to 1.
Intra-articular glucocorticosteroid instillation does not appear to reduce osteitis in the sternocostoclavicular region in patients with SAPHO syndrome.