Karine Jean-Pierre admits Biden has seen a neurologist three times but refuses to say why Parkinson's expert visited the White House in chaotic press briefing

The White House on Monday said that President Joe Biden was not being treated for Parkinson's disease during a bad-tempered press briefing when officials were accused of hiding his medical details.

Press Secretary Karine Jean-Pierre at times struggled to be heard amid a cacophony of questions about the 81-year-old president's health.

She confirmed he had been examined three times by a neurologist but refused to say why a specialist in Parkinson's disease visited the White House eight times in eight months, citing privacy and security concerns.

But that simply triggered a hubbub of questions from the usually docile front row of reporters who wanted a fuller explanation.

'Ed, a little respect please,' said Jean-Pierre to CBS News senior White House correspondent Ed O'Keefe, who wanted to know why she was not prepared to discuss details of Dr. Kevin Cannard's visits, when they were already a matter of public record, revealed by visitor logs. 

The extraordinary scenes cut to the heart of the crisis enveloping the White House and Biden's reelection effort. 

The president's health has been under intense scrutiny since his stumbling performance during his first debate showdown with Donald Trump.

Democratic donors have urged him to stand aside for a younger candidate and nine elected representatives have followed suit.

On top of that, journalists say the White House is not being straight with its answers. 

The result was a string of inquiries about possible neurological conditions, such as Parkinson's disease or hydrocephalus, and a question .  

More questions were raised when it emerged that Cannard visited the White House eight times, including once for a meeting with the president's personal physician, in a period of eight months. 

'I hear you guys, guys, hold on a second,' said Jean-Pierre.

'There's no reason to get back and go back and forth with me in this aggressive way. 

'We are miffed around here about how information's been shared with the press corps,' said O'Keefe.

In particular, reporters pointed out that they last week had asked Jean-Pierre whether the president had received 'any medical exams' since his full February physical. She answered: 'We were able to talk to his doctor about that and that is a no.'

Officials later had to clarify her answer, saying that Biden had in fact been seen by his doctor in the wake of the debate.

'He did not have a medical exam,' she said Monday, as she fended off hostile questions, saying she has not meant to mislead anyone. 'And I stand by that. Matter of fact, the president still stands by that. He had a verbal check in.'

At one point, Jean-Pierre tried to ask for a friendly face to intervene to bring the ranks of journalists. 'Kelly O?' she asked, turning to the Kelly O'Donnell of CBS News, who is the president of the White House Correspondents Association.

'I am not going to devolve [sic] somebody's name and or confirm someone. I'm not going to do that,'she said. 

'That is as privacy for that person. I'm not going to do that. It doesn't matter how hard you push me, it doesn't matter how angry you get with me.'

Monday wasn't supposed to be like this. It began with the president striking a defiant tone in a letter to congressional Democrats saying he would not abandon his campaign.

Then he made a surprise call to MSNBC's 'Morning Joe' show to criticize elites that he said did not understand his support among the Democratic base.

He challenged the naysayers to run against him at the convention. 

'I'm getting so frustrated by the elites. Not talking about you guys by the way ... the elites in the party,' he said.

'They know so much more? If any of these guys don't think I should run ... run against me. Announce for president. Challenge me at the convention.'

The president is also banking on a Thursday press conference as a chance to show that he can still cope with the rigors and scrutiny of being president.