Multiple sclerosis and fabry Disease, two sides of the coin? The case of an Italian family

Background: Multiple Sclerosis (MS) is considered among possible differential diagnosis of Fabry Disease (FD), especially in early stages when findings are suggestive but not diagnostic for MS. We report the case of a family in which FD and MS coexist, offering an overview on clues for differential diagnosis and speculating on shared etiopathogenic mechanisms for these conditions. Methods: Taking as starting point the diagnosis of FD in a dialysis patient during a screening programme, we retrospectively rebuilt his family history and revised clinical and imaging examinations of his five siblings, two of which with previous diagnosis of MS. Results: After genetic testing, two subjects were found positive to a new α-galactosidase A mutation, probably causative for FD classical variant. The two subjects meeting diagnostic criteria for MS were found negative to any GLA gene mutation, therefore initial diagnosis was confirmed. The remaining two siblings resulted unaffected, with neither clinical nor instrumental evidence of FD and MS. Conclusions: Differential diagnosis between FD and MS may be challenging, especially in early clinical stages when only extensive clinical evaluation and correct MRI interpretation may reduce the risk of misdiagnosis. Moreover this report allows speculating on potential etiological and pathogenic mechanisms, common both to FD and MS.