Turnaround times
The quoted turnaround time is from sample receipt in the laboratory, to results authorisation in the Laboratory Information Management system. The times do not include transport of specimen to the laboratory or the administrative process to print and post/email reports. Service users must allow for transport and reporting time when ordering tests.
Clinical background:
Fabry disease is an X-linked disorder caused by deficiency of lysosomal alpha-galactosidase A.Males with classical disease present during the first decade with severe pain in extremities, characteristic skin lesions, gastrointestinal problems and corneal dystrophy. Patients develop renal, cardiac and cerebrovascular disease in adulthood. Presentation of the disorder in female heterozygotes ranges from asymptomatic to the severe disease seen in males but with later onset and slower progression. Male and female patients with mild, late-onset Fabry disease may present with atypical cardiac, renal or cerebrovascular disease. Affected males are diagnosed by finding very low leucocyte alpha-galactosidase A activity, confirmed by identification of a mutation in the GLA gene. Females have normal to low enzyme activity in leucocytes and plasma. A normal result does not exclude Fabry disease. Gene mutation analysis is also recommended when investigating female patients for Fabry disease.
Specimen container paediatric:
EDTA whole blood or blood spot card
Specimen container adult:
EDTA whole blood or blood spot card
Minimum volume paediatric:
1 ml for screening test, 5ml for follow-up test
Minimum volume adult:
1 ml for screening test, 5ml for follow-up test
Transport requirements:
Samples sent at ambient temperature
Availability:
Sample sent to an external laboratory for analysis
Reference ranges:
Blood spot α-galactosidase 6.3 – 47 pmol/punch/hourPlasma α-galactosidase 3 – 20 nmol/ml/hrLeucocyte α-galactosidase 10 – 50 nmol/mg/hr
Other info:
Ensure clinical information is included with requests. Blood spot α-galactosidase is recommended as a first-line screening test. If levels are low, confirmation of leucocyte α-galactosidase is required on a 5 ml blood sample. If Fabry disease is suspected in a female patient, genetic testing is recommended as enzyme levels in female Fabry patients may overlap with control ranges.