By Sara Rossi
MILAN (Reuters) - Four-time Italian Prime Minister Silvio Berlusconi spent the night in a Milan hospital to have tests on a swollen knee, sources said on Friday, confirming reports in the Italian media.
The 77-year-old billionaire media magnate checked into San Raffaele hospital on Thursday evening, the sources close to the situation said, without giving further details on his condition.
Ansa state news agency reported the news citing sources at the hospital. A spokesman for his party had no comment and the hospital could not comment on whether he was a patient.
Next week Berlusconi is scheduled to go before a judge who must decide whether he should serve a one-year sentence from a tax fraud conviction last year doing community service or under house arrest.
A year ago Italian judges were forced to postpone a hearing in the tax fraud trial after he checked into hospital with an eye condition.
A Milan judge, after an examination by a doctor hired by the court, later said the ailment was not a "legitimate impediment" and ordered the trial to continue.
Since last year's conviction Berlusconi has struggled as center-right leader. Dozens of lawmakers split with his party and they now back Prime Minister Matteo Renzi's government while Berlusconi remains in opposition.
Berlusconi's Forza Italia, or Go Italy!, party faces a major electoral test in European Parliament and local elections on May 25. Polls show it is in third place after Renzi's Democratic Party and the anti-establishment 5-Star Movement.
(Additional reporting by Giselda Vagnoni; Writing by Steve Scherer; Editing by Alison Williams)