Has anyone shown an allergy to metal implants? how do you identify if that is the problem and what can be done?

Yes: Usually this shows up as an implant failure. An allergy to the metal can be detected by a patch skin test read at 72 or more hours. However many patients with positive patch test to a metal may have no problem with using it in the implant.

Yes, but: There is a significant controversy whether metal, particularly nickel allergy ,is associated with reactions to metal implants. As you already have reactions around your implants, see a board-certified allergist/immunologist. Patch testing may be helpful and possibly some specialized blood tests for determination of allergy. If allergy to the implants is confirmed, they may have to be replaced.