Add health policy adviser Ezekiel Emanuel to this week's list of White House departures.

Emanuel, the special health policy adviser to the Office of Management and Budget, left the White House earlier this week to return to his job at the National Institutes of Health (NIH), Kaiser Health News reported Thursday.

Emanuel was on loan to the Obama administration from NIH for the design phase of the healthcare reform legislation. It is no surprise that Emanuel is leaving now, Joe Antos, a healthcare fellow at the American Enterprise Institute, told Kaiser Health News.

"We're now into the implementation mode," Antos said. "He was there to make high-level policy recommendations."

The departure comes during a week of personnel reshuffling at the White House. Earlier this week Pete Rouse stepped down as interim chief of staff and was succeeded by William Daley. On Friday morning, the White House announced that Gene Sperling would replace Larry Summers as head of the National Economic Council.

Dr. Emanuel is the brother of former White House chief of staff Rahm Emanuel. This is the first time the Obama administration has not included a member of the Emanuel family.