ICD-10-CM > M00-M99 > M30-M36 > M33 > M33.2 M33.2 Polymyositis Non-Billable/Non-Specific Codes M33.20Polymyositis, organ involvement unspecifiedM33.21Polymyositis with respiratory involvementM33.22Polymyositis with myopathyM33.29Polymyositis with other organ involvement