The 36-year-old man was walking along Edinburgh's iconic North Bridge when the beggar approached him asking for one pound. When he refused he was stabbed in the stomach with a used needle.
An unnamed source told the Edinburgh Evening News the victim had appeared remarkably calm, but was bleeding extensively after the incident.
The injured holidaymaker went into The Scotsman where he had been staying last week and asked staff to call a taxi so he could go to hospital.
The hotel source said: "He had been outside and a guy asked him for a pound. He said he didn't have money on him. Then he just came into the hotel and asked if they could order a taxi because he needed to go to hospital. He had a big hole in his belly."
It is believed he has undergone tests for HIV and hepatitis in hospital.
Police arrested a 38-year-old man, who made his first appearance in court on Monday.
A police spokeswoman confirmed the victim attended the Edinburgh Royal Infirmary for treatment. A police spokeswoman said: "Police received a report of an assault on North Bridge that occurred on Saturday. A 36-year-old man subsequently attended the Edinburgh Royal Infirmary where he received treatment. A 38-year-old man was traced, arrested and charged in connection with this incident and appeared at Edinburgh Sheriff Court."
Local councillor Joanna Mowat said she was relieved that an arrest had been made. She also expressed concerns about aggressive beggars in Edinburgh. "We should look at ourselves and say, 'is this appropriate?' We can't afford for this to happen again. We have to answer questions about how we can stop this happening."
Cllr Mowat said the shocking incident would "strike deep" in the heart of a city with such a popular reputation with tourists.
She added: "Can you imagine what you would think about the city if this happened to you when you were visiting? We pride ourselves on being a safe city but an unprovoked attack is always going to be worrying. I think we can do better than having people begging on the street."
In February this year, police were called to the nearby five-star Balmoral Hotel in Princes Street after a man was found in the foyer in possession of a bloodstained syringe.
And in March last year, a security guard was stabbed with a used syringe after he challenged a shoplifter in the Lidl supermarket in Nicolson Street.
The man "struggled violently" with the guard and stabbed him a number of times with a syringe before running off.