POS1173 CLINICAL PRESENTATION AND TREATMENT OF STERNOCOSTOCLAVICULAR HYPEROSTOSIS (SCCH): A SYSTEMATIC REVIEW AND META-ANALYSIS OF SCATTERED EVIDENCE

Background Sternocostoclavicular hyperostosis (SCCH) is an inflammatory bone disorder within the spectrum of chronic non-bacterial osteomyelitis. SCCH can be a manifestation SAPHO syndrome, standing acronym for synovitis, acne, pustulosis, and osteitis, but also appears as isolated clinical entity without joint skin involvement 1,2 . Consensus on nomenclature, diagnostic classification, therapy currently lacking 3 Literature diffuse, spreads over wide range medical disciplines, calling first systematic overview. Objectives We critically appraised literature with aim to i) gain overview presentation features leading diagnosis ii) evaluate different treatment modalities response. focused in adults, either or part syndrome. Methods conducted review meta-analysis according PRISMA guidelines therapeutic applied adult patients. Studies covering these respective domains were selected. Risk bias was assessed using validated tools study type. Untransformed numerical data double-arcsine transformed proportional analyzed random effects model R-4.0.5; pooled proportions reported 95% confidence intervals (95%CI). Treatment response categorized good, partial, none. Results 28(i) 12(ii) studies included, containing heterogeneous 1818 A female predisposition (67%, 95%CI 60-73) major delay (5 years 3-7) noted. Clinical marked by anterior chest pain (89%, 79-96), swelling (79%, 62-91). Pustulosis palmoplantaris present 53%, 95%CI37-68, whereas acne (8%, 95%CI4-13) peripheral arthritis (24%, 11-39) less prevalent. Inflammatory markers inconsistently elevated autoantibodies HLA-B27 prevalence normal. Histopathology unspecific, cultures almost exclusively negative. Increased isotope uptake (99%, 95%CI96-100) most consistent imaging finding. Amongst manifold treatments (see Figure 1), NSAIDs mainly partially effective. Pamidronate biologicals (mainly TNF-α inhibitors) yielded though heterogeneous, 83%, 60-98 56%, 26-85 respectively. 1. their (data from trials several cohort combined) Conclusion extremely heterogeneous. Timely proves challenging follows increased nuclear examination. Biopsies, HLA-status are non-contributory, biochemical profiles only variably detected. inhibitors emerged promising therapies, powered, placebo-controlled research standardized measures warranted. Inherently, international consensus SCCH’s classification name critical improve scientific collaboration this rare disease, advance development guidelines. References [1]Saghafi M, Henderson MJ Buchanan WW. hyperostosis. YSARH 1993; 22: 215-223. 10.1016/0049-0172(93)80070-v. DOI: papers3://publication/doi/10.1016/0049-0172(93)80070-v. [2]Carroll MB. hyperostosis: review. Therapeutic advances musculoskeletal disease 2011; 3: 101-110. 10.1177/1759720X11398333. papers3://publication/doi/10.1177/1759720X11398333 [3] Kalke S, Perera SD, Patel ND, et al. The sternoclavicular syndrome: experience district general hospital results national postal survey. Rheumatology 2001; 40: 170-177. 10.1093/rheumatology/40.2.170. papers3://publication/doi/10.1093/rheumatology/40.2.170 Acknowledgements authors would like thank Drs. J.W. Schoones, information specialist at Walaeus Library, Leiden University Medical Center, his contribution search strategy selection studies. Disclosure Interests None declared