S.C. Code Ann. § 20-7-1150
A tribunal of this State may enforce a child-support order of another state registered for purposes of modification, in the same manner as if the order had been issued by a tribunal of this State, but the registered order may be modified only if the requirements of Section 20-7-1152, 20-7-1154, or 20-7-1155.1 have been met.