Neuropathic pain in Fabry's disease:: Heterogeneous remission in three years of enzyme replacement therapy

Introduction. Fabry's disease is associated with acute neuropathic pain (NP). When six males with classic Fabry's disease ended three years of enzyme replacement therapy (ERT), studies were conducted to analyse the progression of the NP. Patients and methods. All of them received 1 mg/kg of agalsidase beta every 14 days. NP in hands and feet was evaluated at 0, 6, 12, 24 and 36 months, two modalities being considered: a) very intense pain or Fabry crises (FC), which forced the patient to rest, take analgesics and apply cold locally; b) acroparesthesias (AP), lower intensity itching, tingling and burning sensations that did not prevent them from continuing with their activities of daily living. The intensity of the FC (IFC) and the AP (IAP) were recorded using the Visual Analogue Scale, and the frequency with which both (FrFC and FrAP respectively) appeared was measured in days. The one-tailed Wilcoxon test, binomial distribution and bootstrap method were used to carry out the analysis. Results. After six months of ERT the IFC, LAP and FrCF remained the same, although the FrAP had become worse. As shown by the NP indexes that relate IFC/FrFC and IAP/FrAP, progress was therefore favourable. At one year IFC continued, but FrFC and LAP were lower At two years, the four NP measurements improved in five patients, although the FC and AP indexes did not vary in one patient. At three years, all the NP variables improved in the six patients. The slope representing NP as a function of time in all the bootstrap analyses was found to be p < 0.001. Conclusions. NP responded in a favourable, significant and heterogeneous manner and therefore justifies the early indication of ERT.