QPR had appealed Leigertwood's dismissal for a high tackle on Lee Carsley 45 minutes into the home side's 1-0 win against Blues at Loftus Road on Tuesday night.
However, the Football Association have rejected the appeal and handed the midfielder an extra one game ban as they considered the appeal for wrongful dismissal was deemed to have no prospect of success.
He will now have to serve a four game suspension starting with immediate effect.