Not a doctor, but wifey is. The seizure is most likely a side effect of lupus and how it screws up the biochemical balance in the body, rather than the onset of an emergent condition like epilepsy. But the Doctors will watch it. At least in the USA (and I can't imagine it would be any different in any first-world country), a seizure is considered to warrant deep investigation, EEGs, MRIs, even CT Scans and the like, because it can often be one of the first warning signs of other very serious conditions.
I'll keep Ace in my thoughts; he was always cordial, intelligent, thoughtful, polite, and reasonable... traits that're usually in short supply on internet forums (yes, even on the Escapist.)