User Management System in node.js
I use sails framework and there are some packages that integrates with sails. For authentication i found this package: https://github.com/kasperisager/sails-generate-auth, maybe it help you.
To build on Victor's answer, there is a comprehensive user/role management system for express called sails-permissions that is based on sails.js.
I think you will have to use Drywall and customize it to use mySQL. It's uncommon to use mySQL for node.js as you know already.
Maybe this article will help you with the mySQL integration: