Gangliosides are complex lipids which are found on the surfaces of some neurons.
What the test showed is that there are antibodies of the IgM and IgG classes specific of one ganglioside (GD1a) present in your blood at levels above the reference range of the lab which did the analysis. This can be indicative of Guillain–Barré syndrome.
I would be inclined to discuss the possibility of Guillain–Barré syndrome with your doctor. This general information about it may help you with this
Guillain–Barre syndrome - Wikipedia .