recurring impetigo

my 2 years old son was diagnosed with impetigo 5 months ago.a lesion has started on his cheeks and after a few days on his legs and arms his pediatrician gave him augmentin and isoniazide for oral treatment and bactroban cream for the lesions it seems the wounds are healing but few days after his medication another lesions  formed, same place face and limbs. his pedtrician change his oral antibiotic to clindamycin dalacin c and maintain the bactroban, it seems to be responding the wounds dried faster but the same few days after treatment the lesions came back. we go back to his pediatrician she maintain the clyndamycin but change the cream to bactifree. same result lesions still came back. then we were advised buy the pediatrician to admit our son to the hospital so that he can be given oxcacillin and gentamycin intavenously, he was admitted for 3 days and with home meds of augmentin,skin creams are bactroban and trimycin...1 week after admission lesions still come..please help us my son is all scars and wounds what should we do?..thanks