Twitter widget methods for dynamic widget updating

I am trying to add an option to a profile page for twitter widget and I have a field where users can add their twitter accounts and below it shows a preview of the widget. It works fine if I enter an account and click save and come back. But what I am trying to do is make it dynamic, to refresh the widget with corresponding account when blur event occurs on the text-field.

I have the following code:

var twitterWidget = new TWTR.Widget({
  version: 2,
  type: 'profile',
  rpp: 4,
  interval: 6000,
  width: 'auto',
  height: 300,
  theme: {
    shell: {
        background: '#cccccc',
        color: '#333333'
        },
    tweets: {
        background: '#ffffff',
        color: '#333333',
        links: '#0099cc'
        }
  },
  features: {
    scrollbar: false,
    loop: false,
    live: false,
    hashtags: true,
    timestamp: true,
    avatars: true,
    behavior: 'all'
  }
});
twitterWidget.setUser(twitterUser).render().start();

    $('#twitter_widget_id').change(function(){          
        twitterWidget.setUser($(this).val()).render().start();
    });

In this case it works wrong: it shows only the newest tweets from all the accounts that I entered and in general I'm getting an empty widget.

If I delete the object and create a new one it makes the page blank and then adds the widget.

Does anyone know some public methods for the TWTR.Widget() like re-render() or something like that?

Thanks.