If you have previously been treated for keloids of the earlobes, it would be very imprudent (DUMB!) to have them repierced. The incidence of recurrence of keloids of the earlobes with repiercing may not be exactly 100% but it is extremely high - and not worth the attendant risks. It would be far more advisable to use clip on earrings if you must.
Repiercing is likely to produce regrowth of the keloid and is inadvisable. The keloid should be compressed with pressure earrings. These are sold in a variety of designs and, while not an ideal solution, are beneficial in assisting in the goal of preventing regrowth of the keloid as further surgery can result in additional scarring.