Comparison between alpha-galactosidase A activity in blood samples collected on filter paper, leukocytes and plasma

ObjectivesTo compare alpha-galactosidase A activity in dried blood spots on filter paper, plasma, and leukocytes of Fabry disease patients and healthy controls, and to develop a miniaturization approach of the techniques to measure activity using plasma and leukocytes.Design and MethodsBlood was collected from healthy controls and Fabry disease patients. Two drops were spotted on filter paper. Plasma and leukocytes were separated from the remaining sample. Enzyme activity was assessed by fluorometry.ResultsSignificant positive correlation between standard and miniaturized techniques was observed. Alpha-galactosidase activity differed for male and female subjects when analyzed using filter paper and plasma. New reference and cutoff values were established based on the differences in alpha-galactosidase activity between genders. A good correlation was observed across biological materials assessed.ConclusionsThe establishment of specific values for men and women increases reliability of commonly used techniques to screen and diagnose Fabry disease.

► DBS, plasma and leukocytes GLA activity of FD patients and healthy individuals.
► DBS and plasma GLA activities for male are different to female activities.
► New reference and cutoff values were established.
► A good correlation was observed across biological materials assessed.
► We miniaturized techniques reducing the cost of these tests.