Julian Assange's health is "compromised" and he is suffering from osteoperosis and dental problems, the Mirror has been told.
But the Wikileaks founder remains defiant after being arrested for breaching bail by claiming asylum in the Ecuadorian embassy.
But he was branded a "narcissist" by a judge as he was found guilty of skipping bail.
Appearing in court, Mr Assange's lawyer said the alleged computer hacker had said all along that the legal case against him was a ruse to deliver him into the hands of the United States.
Sources close to Wikileaks said a US extradition request had been filed in December 2017, but not made public until shortly after his arrest.
Barrister Liam Walker told the court: "It's been proved Mr Assange was absolutely right."
Speaking outside court, his lawyer Jennifer Robinson said Assange's message to supporters was: "I told you so."
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A source close to Wikileaks said Mr Assange’s health is “compromised” after spending seven years in the confines of the Ecuadorian embassy.
They said: “He's as well as can be expected.
“He is fighting on, but his health is compromised because he's been in an embassy for however many years, and he's not had sunlight and he's not been able to move around.
“I don't think people understand that it's a very small space, the Ecuadorian embassy. They're not a country with a massive pile in Knightsbridge, it's a few rooms.
“He's got dental problems. He's got osteoporosis because he's had a lack of vitamin D. And he's got other ailments.
“I’ve seen him and he's...you know, he's suffering. He's a human being, he's suffering. Whatever the reason for that, it's a fact.”
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Earlier, Mr Assange had been branded a "narcissist" by a judge as he faced court after struggling with police as he was dragged from the Ecuadorian embassy.
Finding Assange guilty of breaching the Bail Act, the judge said of Assange: "He has chosen not to give evidence, he has chosen to make assertions about a senior judge not having the courage to place himself before the court for the purpose of cross-examination.
"Those assertions made through counsel are not evidence as a matter of law.
"I find they are not capable of amounting to a reasonable excuse."
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He went on to describe Assange's defence as "laughable", adding: "Mr Assange's behaviour is that of a narcissist who cannot get beyond his own selfish interests.
"He hasn't come close to establishing 'reasonable excuse'.
"His behaviour through his counsel is shameful."
Remanding Assange in custody, the judge told him he will be sentenced at a date to be set in Southwark Crown Court, the judge added: "This is a case which merits the maximum sentence, which is 12 months in the Crown Court."
'Selfish narcissist' Julian Assange found guilty of skipping bail
He will next appear at Westminster Magistrates' Court on May 2 by prison video-link in relation to the extradition case, which will be listed for a mention hearing every seven days.
In a final barbed remark, the judge suggested Assange should "get over to the US" and "get on with your life".
