A doctor told a patient who he had allegedly performed oral sex on at Ealing Hospital "you were giving me the impression you were in the mood", a court heard.
Paul Andrew Fox , of Rosebury Road, Fulham , stands charged of causing the person to engage in sexual activity without consent, involving the penetration of the defendant's mouth with the complainant's penis when he did not consent.
It is alleged the incident occurred at Ealing Hospital's GUM Sexual Health Clinic on September 1, 2015.
The 52-year-old had pleaded not guilty on May 16 at Isleworth Crown Court earlier this year.
Jurors at same court heard on Monday December 5 the alleged victim had initially attended the clinic in June 2015.
In the afternoon of day one of the trial, jurors were played an alleged recording between Dr Fox and the claimant, which was said to have been recorded on the claimant's iPhone.
Eloise Marshall, prosecuting, told jurors the claimant "asked why Dr Fox had sucked his penis" in the recorded conversation.
Ms Marshall added that, in the recording, Dr Fox had said: "You were giving me the impression you were in the mood".
The claimant is alleged to have said in the recording "what was that for?"
The court heard that Dr Fox had allegedly replied in the recording: "I apologise for that, it was not part of the test.
"Do you have sex with men?
"Just take it as a sign of appreciation".
Earlier in the trial at Isleworth Crown Court, the jury heard the alleged victim had initially attended the clinic in June 2015.
He was later diagnosed with prostatitis, a non-sexual infection.
The alleged victim was referred to Fox, who undertook an examination, the court heard, before a follow up appointment was arranged, which the alleged victim did not attend.
Following this, Fox contacted the complainant by phone call asking him why he was absent, the court heard.
The complainant, who was aged 21 at the time, then undertook a prostatitis exam on September 1, 2015, the court heard, performed by Dr Fox.
Jurors were told the complainant took off all his clothes and was asked to sit in the "doggy position", lying on his hands and knees.
A prostatitis exam, the court heard, involves the massaging of the prostate for a fluid sample.
After a sample had been taken, Dr Fox continued to touch the claimant's penis, jurors were told.
The claimant was asked to stand up, where at some point during the examination he felt his penis was "semi erect" and recalls Dr Fox saying "I think we're getting it", it was alleged.
Fox continued touching the patient before he "sucked" the defendant's penis, it was said.
Eloise Marshall, prosecuting, said: "It was at this point that Dr Fox took his penis and placed it in his mouth and sucked it.
"(The complainant) was shocked by this. He touched Dr Fox's shoulder in a bid to get this to stop.
"After a short period he ejaculated in to Dr Fox's mouth.
"He did not see what Dr Fox did with the semen in his mouth but it is his belief that Dr Fox swallowed it.
"The victim felt confused, angry and felt upset at what just happened".
Following the alleged incident, Fox told the complainant to "take it as a sign of appreciation", the court heard.
The trial continues.
The defendant is currently suspended from Ealing Hospital.
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