Specialists at Our Lady's Children's Hospital Crumlin in Dublin have warned of a crisis in the gastroenterology service, with dangerously long waiting lists for children.
Figures obtained by RTÉ News show that 166 children are waiting for a bowel check or a gastrointestinal check at the hospital, which provides a national referral service.
An endoscopy is a procedure for looking inside the body, using a flexible tube, to check for bowel or gastrointestinal problems.
The next available appointment at the Crumlin hospital for a non-urgent endoscopy is between 12 and 18 months.
In a series of letters written since 2009, between doctors and hospital management and to the HSE, specialists have repeatedly warned of 'a real and immediate risk to children' due to delays in checking for conditions, such as inflammatory bowel disease, colitis and Coeliac disease.
Consultants say they are prepared to put in whatever time or effort is needed to deal with the crisis but need more resources.
Since January, 40 gastroenterology patients were referred to the National Treatment Purchase Fund.
The hospital says that all patients are prioritised by clinical need by consultants and that all patients that are deemed urgent receive their treatment in the appropriate time.