CMS published MLN Matters article number SE1521, which states:

“For redeterminations and reconsiderations of claims denied following a post-payment review or audit, CMS has instructed MACs and QICs to limit their review to the reason(s) the claim or line item at issue was initially denied.”

What this means is that if you have an audit and a claim is denied for a reason, e.g. not medically necessary, then when you appeal that denial, the MAC cannot deny the claim for a different reason, e.g. signature not legible. The same applies to a denial in the Redetermination decision as the QIC cannot deny for a different reason than what was stated in the original denial. Thus, the Redetermination decision and the Reconsideration decision are limited to the original reason for the denial.

This went into effect for Redetermination and Reconsideration requests received by a MAC or QIC on or after August 1, 2015.

It does not apply to denials that result from failing to submit requested documentation needed to process the claim. It also does not apply to denials from pre-payment reviews.