Twitter Auto DM Reply with a specific message and hashtag from original tweet

I am looking for a program or script that will automatically send a DM to a user after they send out a specific tweet. The DM needs to contain the same hashtag that the user tweeted plus a message. The hash tag that must be included is not known until the user tweets it. Also this must be done within a matter of seconds. If anybody knows of something like this or can develop one please let me know. Any help would be appreciated. Thanks much!

Im also interested in the answers. Can't find one anywhere.

You can't DM anyone unless they follow you.

The purpose of the program is for Nike Twitter RSVPs. They do not follow me yet I am still able to DM them. Maybe as a biz or verified acct they have a different setup. Not sure.