The european registry for rare bone and mineral conditions (EuRR-Bone): results of a survey on osteogenesis imperfecta and fibrous dysplasia McCune-Albright síndrome

Abstract

Introduction: EuRR-Bone offers an electronic reporting system (e REC) that captures the occurrence of rare conditions within reference networks such as ERN BOND and Endo-ERN. Secondary surveys following the reported cases in e-REC collect a brief amount of data for understanding the clinical presentation of the reported condition. Osteogenesis Imperfecta (OI) and Fibrous Dysplasia/McCune-Albright Syndrome (FD/MAS) are two rare conditions that require expert care but the extent of variation in care delivery across expert centres is unclear. Methods: Between May 2020 and May 2021, 80 FD/MAS and 76 OI cases were reported in e-REC. Reporters were invited to complete a secure online questionnaire. The questionnaire was completed in 123/ 156 cases (68%) by 12 centres from eight countries. Results: The median age at presentation for FD/MAS was 20 years (range, 0, 72) and 3 years (range 0, 47) for OI. History, clinical findings and imaging were collected in the diagnosis of both conditions. Of 58 confirmed cases of FD/MAS 8 (14%) had genetic testing; 30/31 confirmed cases of OI had genetic testing (97%). Of 58 FD/MAS cases, endocrinopathies were tested in 38 (65%), Gonadotropin-Independent precocious puberty was the commonest pathology (24%) followed by GH excess and Hyperprolactinemia (both 8%). Mobility was assessed in 16/ 31 (51%) OI cases, using clinical data in 43%, and a 6-minute walk test in 25%. Cardiovascular morbidity was investigated in 17/31 (52%) OI cases, pulmonary problems were reported in 1/31 (3%). Quality of life was assessed in 41% of FD/MAS cases (5/25 pediatric and 20/33 adult cases) and 32% of OI cases (10/30 pediatric patients). Validated questionnaires (e.g.EQ5D, BPI) were used only in FD/MAS patients. Conclusion: Although the clinical care of OI and FD/MAS at expert centres is variable, there are some outcomes that are collected routinely by the majority and may represent the core dataset that should be used as a minimum to unify data collection across centres.