Table 3 Summary of confirmatory tests for LOPD
Test | Description | Pompe presentation |
|---|---|---|
Lymphocytes for GAA | GAA assayed in purified lymphocyte preparations | GAA activity reduced |
Fibroblast cultures for GAA | GAA assayed in cultured fibroblasts from skin biopsy | GAA activity reduced |
Genetic testing | Targeted mutational analysis, full sequence analysis, or deletion/duplication analysis | Pathogenic mutations may be detected |
Muscle biopsy | Histology or immuno-histology of muscle biopsy samples | Vacuoles that stain positively for glycogen, with accumulation in the lysosomes and cytosol observed in the advanced stages of the disease |
GAA activity reduced | ||
May be normal or show non-specific changes |