I certainly don't know about specific case long-term reactions, but while my feet were almost 100% covered in 3 layers of colors a couple of weeks ago my local go-to guy asked me an interesting question that might pertain to this subject, that being:
"Are you or do you know if you're allergic to Sharpies?"
Seems he has seen and discussed with other tattooists regarding occasional tattoos that take 6-7 months to heal completely - all of which seems to revolve around Sharpie hand drawn pieces. He wasn't aware of any eventual tattoo or ink failures, just exceptionally prolonged complete healing.