Robert F. DeMayo MD, Presenter: Nothing to Disclose

Andrew Halldor Haims MD, Abstract Co-Author: Nothing to Disclose

Matthew Christian McRae, Abstract Co-Author: Nothing to Disclose

Ruhua Yang, Abstract Co-Author: Nothing to Disclose

Pramod Kumar Mistry MD, PhD, Abstract Co-Author: Nothing to Disclose

To correlate skeletal pathology in Gaucher Disease (GD), as quantified by the MR-based bone marrow burden (BMB) score, with genotype and spleen status.

Two radiologists retrospectively reviewed MR examinations of the lumbar spine and femora in 47 individuals with GD (generally representative of the Gaucher patient population in the U.S. in terms of distribution of genotypes and prevalence of enzyme replacement therapy) and determined BMB scores by consensus based on previously published criteria. BMB scores were then correlated with genotype and spleen status.

With respect to genotype, N370S compound heterozygotes had significantly higher BMB scores than N370S homozygotes overall, in the lumbar spine and in the femora. Among the three most common compound heterozygotes, the N370S/L444P and N370S/IVS2+1 genotypes had consistently high BMB scores, while the N370S/84GG genotype had more variable BMB scores, but these differences were not statistically significant. With respect to spleen status, there was a significant positive correlation between an enlarged or surgically absent spleen and BMB scores overall, in the lumbar spine and in the femora. Femur and lumbar spine BMB scores had a significant but weak positive correlation.

Skeletal pathology in GD, as encapsulated in the BMB score, is significantly correlated with genotype (specifically, the number of copies of the N370S allele) and spleen status. The N370S allele has an ameliorative influence on marrow disease, while splenectomy or splenomegaly is a marker for greater marrow infiltration. Femur and lumbar spine BMB scores independently illustrated both the protective effect of the N370S allele and the adverse implication of splenectomy but were only weakly correlated, suggesting axial and appendicular components of disease are related but distinct and supporting the utility of multicompartment imaging evaluation.

BMB scoring effectively encapsulates clinically relevant associations between marrow infiltration, genotype and spleen status and conveys distinct information by assessing axial marrow pathology.

DeMayo, R, Haims, A, McRae, M, Yang, R, Mistry, P, Correlation of MR-based Bone Marrow Burden Score with Genotype and Spleen Status in Gaucher Disease.  Radiological Society of North America 2007 Scientific Assembly and Annual Meeting, November 25 - November 30, 2007 ,Chicago IL. http://archive.rsna.org/2007/5012267.html