Rihanna was trolled by James Cook children's nurse Paul Stephens. Getty

A children's nurse has been dismissed after tweeting that pop superstar Rihanna looked like a 'borderline lesbian'.

Paul Stephens, who worked at Middlesbrough's James Cook University Hospital, made abusive comments about Islam, homosexuality, and disabled people on social media site Twitter and on two blogs, a tribunal has heard.

Stephens had been publishing remarks on his 'Musings of a Madman' and 'Thirty Four not out' blogs and Twitter for almost three months before bosses received a complaint letter on 15 October 2012 from his ex-wife Emma Barber, raising concerns about his online trolling.

One particular entry was submitted while he was on duty and used foul language to refer to a boy he was caring for in a paediatric unit.

With the help of IT services, Jane Wiles, a senior colleague at James Cook University Hospital, was able to access the defamatory remarks and he was subsequently sacked. He now faces being struck off by the Nursing and Midwifery Council (NMC).

During the tribunal to determine his fate, Wiles said: "I felt that as Paul was a children's nurse he was meant to be acting as a role model, and I was concerned that children could access Paul's comments that he was posting.

"Paul perceived the comments as writing in jest and being funny. In my opinion there was a significant naivety on Paul's part."

Stephens admits all charges including using social media platforms to post discriminatory comments in relation to disabled people, gay people, and Islam, but insists he was "just trying to be funny".

"It was an admittedly stupid way of letting off steam," he said in a letter to the NMC.

The hearing continues.