Bone Loss Study in Type 1 Gaucher Disease by Two Different Technologies

Background: Bone disease is the most important source of disability in type 1 Gaucher disease (GD1). High percentage of patients present generalized osteopenia and osteoporosis with reduced bone mass. It is important to know the risk of bone mass lost in order to avoid the bone resorption. The standard technique to evaluate bone disease is Dual-Energy X-ray Absorptiometry (DEXA) that measures bone density in the axial skeleton. Nevertheless other procedure to exam bone density using ultrasound (US) can measure the amount of mechanical energy transmitted by the bone, as well as their speed of transmission (BUA).

Aims: In order to evaluate bone disease indicators in GD1, we have planned a comparative analysis in GD1 by both techniques to exam individual variability in bone mineral density and to study the response to therapy.

Patients and Methods: 24 adults GD1 patients diagnosed in last 5 years and 15 healthy controls stratified by age and gender were analyzed. Bone marrow changes have been evaluated by a semi quantitative score (S-MRI, Roca et al 2006 Eur J Radiol). To analyse the bone density we have used the Z-score quantification in L5 and femur head, calcaneus US was performed simultaneously determined BUA and bone density, in addition GBA genotype, clinical characteristics and subrogate biomarkers profile included chitotriosidase, CCL-18, MIP- 1b were analyzed. The advantages/disadvantages of each procedure and the correlation of results with the clinical characteristics, S-MRI, response to therapy, have been analyzed.

Results: Osteopenia in GD is present in 85% of cases, it progresses with age and has been correlated with the severity of the disease and response to therapy. BMD evaluation by DEXA in GD1 is well documented but the special physio-pathological characteristics of GD make the use of US feasible and BUA results provide more information about the risk of skeletal complications.

Comments: More experience is needed in order to precisely define the role of bone US exam in the management of GD patients. This work has been partially sponsored by FIS 07/90938 and CIBERER U-752