LAUSR

Inflammatory bone syndromes, such as SAPHO (synovitis, acne, pustulosis, hyperostosis and osteitis) and CRMO (chronic recurrent multifical osteomyelitis) are rare and have not been extensively described in the existing literature. Although there have been proposed classification and diagnostic criteria, there is still limited consensus and uniformity of approach in identifying and treating these patients. This may be due to a lack of data and understanding about the nature and prognosis of these conditions. Attempts to characterise, especially in adult populations, has been limited thus far. As a tertiary metabolic bone service with an allied regional sarcoma service, we present further data on these conditions in an adult population. Retrospective analysis of notes of patients, with a diagnosis of SAPHO and CRMO, that were registered on a departmental database was performed. Data on demographics, symptom onset and character, serum and radiological tests and treatment were analysed. 77 adults were identified with a diagnosis of SAPHO and CRMO, with a 60:40 % split respectively. Female preponderance was noted with 74% of this cohort represented. SAPHO patients tended to present slightly later with a mean age of symptom onset of 37 years as compared to 24 years in the CRMO group. Diagnostic delay was evident with mean time to diagnosis averaging 34 months. Pain and bony swelling were the most common symptoms (99% and 39% respectively), with the clavicle, sternum and spine being the most common sites involved. Osteitis was a universal feature in both groups, whereas skin and inflammatory joint involvement was more of a feature of SAPHO patients (59% vs 39%). There is limited consensus on appropriate diagnostic tests. This was reflected in this cohort with variable testing of inflammatory markers, serological testing of HLA B27 and extent and modality of imaging. Non-steroidal anti-inflammatories (NSAIDS), intravenous bisphosphonates, steroids and anti-microbials were all employed as treatment options, although efficacy was difficult to establish in this retrospective analysis, a significant source of referrals were from the local Sarcoma Unit; this may have introduced a degree of bias in our results. As rare conditions, promoting awareness, having an index of suspicion and early referral to specialist centres would help address current issues faced by this patient population. Several national and international disease registries are in development and will undoubtly help to standardise data collection in order to guide further work in this area. Future studies examining treatment efficacy in current as well as emerging biological therapies, such as anti-tumour necrosis factor, anti- interleukin 1 and 17 agents, would be of significant value. T. Gill None. J. Bubbear None. R. Keen None.