A 10-year-old boy was so addicted to video gaming he had to be treated in hospital for a distended bowel and bladder that ballooned out of his pelvis after he stopped going to the toilet to stay on the games, a top paediatrician revealed yesterday.

Dr Jo Begent, a consultant paediatrician at University College Hospital (UCH) in London, said the boy was playing World of Warcraft, Call of Duty and Fifa eight hours at a time with his gaming addict father and become so seriously constipated his bowel and bladder stopped functioning.

She told the NSPCC’s annual conference yesterday that when the boy arrived at the clinic, she initially thought the hard “craggy mass” protruding out of his pelvis was a cancer but an MRI scan revealed it was the distended bowel and bladder.

Dr Begent, who is also an NSPCC trustee, said it was the worst of a regular flow of cases she has to deal with of children addicted to gaming or social media, with each accounting for one or two cases a month, including some where the child had dropped out of school.

She said the case showed gaming and social media was not only damaging the mental, emotional and educational wellbeing of children but also harming their physical health.