Plasma Globotriaosylsphingosine Level as a Primary Screening Target for Fabry Disease in Patients With Left Ventricular Hypertrophy.

Background: Although previous studies have suggested a certain prevalence of Fabry disease (FD) in left ventricular hypertrophy (LVH) patients, the screening of FD is difficult because of its wide-ranging clinical phenotypes. We aimed to clarify the utility of combined measurement of plasma globotriaosylsphingosine (lyso-Gb3) concentration and a-galactosidase A activity (alpha-GAL) as a primary screening of FD in unexplained LVH patients. Methods and Results: Between 2014 and 2016, both lyso-Gb3 and alpha-GAL were measured in 277 consecutive patients (male 215, female 62, age 25-79 years) with left ventricular wall thickness >12 mm on echocardiogram: 5 patients (1.8%) screened positive (2 (0.7%) showed high lyso-Gb3 and 4 (1.4%) had low alpha-GAL levels). Finally, 2 patients (0.7%) were diagnosed with clinically significant FD. In 1 case, a female heterozygote with normal alpha-GAL levels had genetic variants of unknown significance and was diagnosed as FD by endomyocardial biopsy. The other case was a male chronic renal failure patient requiring hemodialysis, and he had a p.R112H mutation. In both cases there were high lyso-Gb3 levels. Conclusions: The serum lyso-Gb3 level can be relevant for clinically significant FD, and combined measurement of lyso-Gb3 and alpha-GAL can provide better screening of FD in unexplained LVH patients.