Prognostic Factors From an Epidemiologic Evaluation of Fibrous Dysplasia of Bone in a Modern Cohort: The FRANCEDYS Study

Abstract

Fibrous dysplasia of bone (FD) is a rare genetic but sporadic bone disease that can be responsible for bone pain, fracture, and bone deformity. The prognosis may be difficult to establish because of the wide spectrum of disease severity. We have analyzed the data from the French National Reference center for FD. We have established a database from standardized medical records. We have made descriptive statistics of the various forms of FD and examined the prognostic factors by multivariable logistic regression analysis, with a parsimonious stepwise method. The primary outcome was a clinically relevant composite index combining bone pain (visual analogic scale >3) and/or incident fracture. In our modern cohort of 372 patients, the median age at diagnosis was 23 years. The revealing symptom (at a median age of 18 years) was bone pain in 44% of patients and a fracture in 9%, but the diagnosis was fortuitous in 25% of cases. Monostotic forms represented 58% of patients and polyostotic forms 42%. The femur was the most commonly affected bone (44% of patients), followed by the skull (38%). Twelve percent of patients had McCune-Albright syndrome (MAS). With a median duration of follow-up of 7 years among 211 patients, we observed an incidence of fracture of 17% and 51% of patients had no bone pain at the end of follow-up (with or without bisphosphonate therapy). In univariate analysis, younger age at diagnosis, renal phosphate wasting, a polyostotic form, prevalent fracture, and bisphosphonate use were significant predictors. In the multivariate model, the polyostotic form and bisphosphonate use remained significant predictors. In conclusion, in a national referral center for FD, one patient on follow-up out of six had incident fracture. A polyostotic form was the main risk factor of a poorer outcome. © 2016 American Society for Bone and Mineral Research.

The value of 99mTc-methylene diphosphonate single photon emission computed tomography/computed tomography in diagnosis of fibrous dysplasia

“…Patients are usually asymptomatic and detected incidentally on imaging studies that are performed for other purposes. In rare symptomatic cases, FD can present as bone pain, deformity, or pathologic fracture [1, 2]. 99m Tc-MDP ( 99m Tc-labeled methylene diphosphonate) whole-body bone scans (WBS) has been widely used for detection of metastasis for various malignant diseases.…”

Effect of Intranasal Calcitonin in a Patient with McCune-Albright Syndrome, Fibrous Dysplasia, and Refractory Bone Pain

“…Benhamou et al [8] recently conducted an analysis of 372 patients with FD, 42% of whom were diagnosed with a polyostotic form and 12% with MAS. The main symptom at diagnosis was bone pain, which occurred in 44% of patients, followed by fracture in 9%.…”

Clinical and translational pharmacological aspects of the management of fibrous dysplasia of bone

“…An essential first step before considering the use of any antiresorptive agent, however, is the identification and treatment of FGF23‐mediated hypophosphataemia, potentially leading to increased pain, deformity and increased fracture risk . Treatment of FGF23‐mediated hypophosphataemia requires the use of active vitamin D metabolites or analogues due to the inhibitory effects of increased levels of FGF23 on the renal α‐hydroxylase enzyme resulting in low circulating levels of 1,25‐dihydoxy vitamin D, as also observed in X‐linked hypophosphataemic rickets .…”