OBJECTIVES: Fabry-Anderson disease  (α-galactosydase A deficiency) is a rare , x-linked lysosomal storage disorder that can cause early death from renal, cardiac and cerebrovascular involvement. The specific treatment currently available for Fabry-Anderson disease consists of intravenous enzymatic replacement therapy  (ERT) every 2 weeks of the enzyme α-galactosidase A. The aim of the study was to evaluate the economic impact of the Fabry-Anderson Disease treatment. METHODS: The study was a naturalistic, longitudinal retrospective Cost of Treatment study. Patients were enrolled during the 2001-2004 period and followed until 2007. Direct healthcare resources attributable to disease management (drugs, ambulatory care, day case treatments, hospitalizations, specialist visits, diagnostics and laboratory exams) were quantified using National Health Service (NHS) tariffs expressed in Euro 2008. NHS perspective was adopted.Health-related quality of life information were also collected using SF-36 questionnaire at the enrolment and after 2 and 5 years of treatment. METHODS: T RESULTS: We enrolled 15 patients (males 53.3%, mean age of 40.27±14.76 y.o.) from the Nephrology Department of the University “Federico II” of Naples, with a  mean follow-up of 5.53±1.13 years.The average monthly cost of care was  €22,536.46±€2,247.93 per patient, mainly because of treatment products.  ERT therapy represented 96.2% of the expenses.SF-36 results showed a significant improvement in all the domains in particular in the physical domains. CONCLUSIONS: This is the first study evaluating the socio-economic impact of Fabry-Anderson Disease treatment in Italy. This study showed that this rare disease requires large  amounts of resources  for the management, but it also demonstrated that effective care provides a satisfactory quality of life.To the best of our knowledge this seems to be the highest cost of treatment.