Mo. Rev. Stat. § 354.554

Each community-based health maintenance organization shall offer coverage that allows an enrollee who suffers from a life-threatening condition or a degenerative, disabling condition requiring a regimen of specialized medical treatment lasting for six months or more to receive a standing referral for specialty care case management by a physician or specialty care center with expertise in treating the condition. Under such specialty care case management, the provider shall coordinate primary and specialty care for the enrollee under a treatment plan approved by the health maintenance organization in consultation with the enrollee's primary care provider and the specialist physician or specialty care center.