Viral infections and phenotypic heterogeneity in Gaucher disease

Gaucher disease, the most common lysosomal storage disorder, is remarkable for its tremendous phenotypic heterogeneity even among patients with the same genotype. Beyond mutations at the 1q21 locus, there may be other genetic and environmental factors that impact on the natural course of Gaucher disease and indeed may trigger symptoms and signs. Among candidate events are viral infections such as the Epstein-Barr virus (EBV) or cytomegalovirus (CMV). The purpose of this study was to ascertain if indeed prior infection with EBV or CMV in patients homozygous for the most common mutation, N370S (1226G), is predictive of a more severe phenotype. Evidence for an EBV virus was IgG and IgM antibodies to early antigen and IgG anti-EBNA. For CMV infection, IgG and IgM antibodies were sought. This study failed to demonstrate any correlation between prior EBV or CMV infection and clinical course of Gaucher disease in patients homozygous for the N370S (1226G) mutation. The only positive finding was a higher level of anti-EBNA antibodies among patients with moderate/severe disease. In conclusion, other than a small subset of patients who showed a pattern comparable to immunosuppression, there was no association between severity of Gaucher disease and prior EBV or CMV infection.