title: Globotriaosylsphingosine (lyso-Gb3) might not be a reliable marker for monitoring the long-term therapeutic outcomes of enzyme replacement therapy for late-onset Fabry patients with the Chinese hotspot mutation (IVS4+919G>A).
abstract: BACKGROUND
  In Taiwan, DNA-based newborn screening showed a surprisingly high incidence (1/875 in males and 1/399 in females) of a cardiac Fabry mutation (IVS4 + 919G > A). However, the natural course, long-term treatment outcomes and suitable biomarkers for monitoring the therapeutic outcomes of these patients are largely unknown.
  
  
  METHODS
  Fabry disease (FD) patients who had received enzyme replacement therapy (ERT) for more than 1 year were enrolled in this study from December 2008 to April 2013. Periodic echocardiography and serum globotriaosylsphingosine (lyso-Gb3) analysis were carried out. Before and after ERT, left ventricular mass index (LVMI) and serum lyso-Gb3 level were compared and the correlation between the change of LVMI and the change of serum lyso-Gb3 were also analyzed.
  
  
  RESULTS
  Thirty-six patients, in four patient groups, were enrolled: (1) 16 males with IVS4 + 919G > A mutation; (2) 7 females with IVS4 + 919G > A mutation; (3) 2 males with classical mutations; and (4) 11 females with classical mutations. The follow-up period was 13-46 months. There were significant LVMI reductions after ERT in all four groups after excluding confounding factors. However, interestingly, serum lyso-Gb3 decreased significantly in the early period after ERT in all groups, but increased gradually after an average of 11.1 months after ERT in late-onset male and female Fabry groups, even when their LVMI still decreased or remained stable. Furthermore, there was no correlation between the change of serum lyso-Gb3 and the change of LVMI in both classical and IVS4 + 919G > A FD patients.
  
  
  CONCLUSIONS
  Although lyso-Gb3 has a high diagnostic sensitivity in late-onset Fabry patients and has a good response to ERT during the early stages, it might not be a reliable marker for monitoring the long-term therapeutic outcomes of ERT for late-onset Fabry patients with the Chinese hotspot mutation (IVS4 + 919G > A).
authors.forename: Hao-Chuan
authors.initials: HC
authors.lastname: Liu
authors.forename: Hsiang-Yu
authors.initials: HY
authors.lastname: Lin
authors.forename: Chia-Feng
authors.initials: CF
authors.lastname: Yang
authors.forename: Hsuan-Chieh
authors.initials: HC
authors.lastname: Liao
authors.forename: Ting-Rong
authors.initials: TR
authors.lastname: Hsu
authors.forename: Chiao-Wei
authors.initials: CW
authors.lastname: Lo
authors.forename: Fu-Pang
authors.initials: FP
authors.lastname: Chang
authors.forename: Chun-Kai
authors.initials: CK
authors.lastname: Huang
authors.forename: Yung-Hsiu
authors.initials: YH
authors.lastname: Lu
authors.forename: Shuan-Pei
authors.initials: SP
authors.lastname: Lin
authors.forename: Wen-Chung
authors.initials: WC
authors.lastname: Yu
authors.forename: Dau-Ming
authors.initials: DM
authors.lastname: Niu
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000378:metabolism*; D056947:Enzyme Replacement Therapy; D000795:Fabry Disease / Q000235:genetics / Q000378:metabolism / Q000628:therapy*; D005260:Female; D006017:Glycolipids / Q000378:metabolism*; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D009154:Mutation; D015997:Neonatal Screening; D013107:Sphingolipids / Q000378:metabolism*; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D015415:Biomarkers; D006017:Glycolipids; D013107:Sphingolipids; C063288:globotriaosyl lysosphingolipid