U.S. Rep. Jesse Jackson, Jr.’s office is providing few details about his unexpected medical leave of absence. His office on Monday disclosed that the Chicago Democrat, a 17-year congressional veteran, is being treated for exhaustion.

The three-sentence statement said Jackson went on medical leave just over two weeks ago, though his offices remain open.

“He asks that you respect his family’s privacy,” read the statement.

Jackson’s spokesman, Frank Watkins, said he would have no further comment.

Just last week, a Jackson fundraiser and family friend, Raghuveer Nayak, was arrested by federal authorities. The U.S. attorney said Nayak engaged in a kickback scheme to drive business to surgical centers he owned.

Nayak had also been a central figure in the trial of ex-governor Rod Blagojevich. The feds said Nayak promised to raise millions of dollars for the ex-governor’s campaign fund if Blagojevich appointed Jackson to the U.S. Senate.

Jackson has denied any knowledge of the scheme, but the issue remains part of an investigation by the U.S. House Ethics Committee. That panel has yet to decide the case.

This past March, Jackson faced a primary challenge from former U.S. Rep. Debbie Halvorson. Despite the bruising nature of the campaigns, Jackson won handily, with more than 70 percent of the vote.

In the November election, he’ll face Republican Brian Woodworth. Independent candidate Marcus Lewis also filed his paperwork with the Illinois State Board of Elections, but could face a ballot challenge.

The timing of Jackson’s announcement, released Monday after regular business hours, is curious. Monday was the deadline for independent and third party candidates in Illinois to file for the November ballot.

Jackson has already missed more than 30 votes on the U.S. House floor.