Great Ormond Street children’s hospital unnecessarily gave patients potentially dangerous drugs, subjected them to invasive tests and wrongly diagnosed them with a rare allergy, it can be revealed.

An inquiry into the world-renowned London hospital’s care of children with gut conditions found it was putting patients’ physical and mental health at risk, previously unpublished documents show. Misdiagnosis and over-treatment also saw patients put on very strict “exclusion diets” which brought no benefit.

The hospital’s own top doctor said that its gastroenterology department was managing eosinophilic gastrointestinal disorders (EGID) in a clinically “aggressive” and risky way that was at odds with usual medical practice.

EGID is an inflammation of the gut which can cause vomiting, diarrhoea and stomach pain, sometimes described as a complex food allergy as children cannot eat some foods.

Patients’ families, hospital staff and senior doctors in other hospitals began raising concerns about the gastroenterology department as far back as 2011. However, they have still not been completely resolved, despite several inquiries and major improvements having been made.

The controversy has been uncovered in a year-long investigation by the Bureau of Investigative Journalism and Amazing Productions, whose documentary airs on ITV on Wednesday. Secret hospital documents obtained by the BIJ show it called in outside experts in 2011, 2012 and 2015 to inquire into practices within the department after receiving unusually high numbers of complaints from families and after doctors both internally and externally expressed alarm. It is unclear how many patients were wrongly treated, although one document from 2015 saysGOSH’s gastroenterology team was treating “around 400 children” who had been diagnosed with the disorder. The full findings of the last of those three probes, an “invited review” by the Royal College of Paediatrics and Child Health, have never been disclosed – until today.

The Royal College panel of four leading experts wrote to the hospital before starting the inquiry, saying they had “specific patient safety concerns … which leads us to believe the way the service is currently delivered may be causing avoidable harm to children”. Hospital staff and other NHS medics believed “the gastroenterology team ‘over-investigates’ and ‘over-diagnoses’. This, they felt, results in children undergoing invasive procedures and treatments which could unnecessarily compromise their physical or psychological wellbeing”, the letter added.

The hospital has admitted failings and apologised to patients affected. It has identified an unspecifiednumber of patients to the Care Quality Commission, the NHS watchdog, who, it admitted, had come to harm.

The Royal College also highlighted how some patients being treated for EGID had undergone “initial or multiple … gastroscopies and other invasive or lengthy procedures” before their symptoms had been properly considered, referring to a potentially unpleasant procedure in which a tiny camera is put down the throat to let doctors assess someone’s gullet and stomach.

GOSH staff had also diagnosed gastrointestinal conditions, including EGID, “excessively”, the panel found. In an extraordinary move, doctors in other hospitals were so concerned that they had stopped sending patients to Great Ormond Street .

In a 2016 briefing, Great Ormond Street had admitted that some approaches had been 'at the aggressive end of the spectrum'

“Several clinical leads in secondary and tertiary trusts told us that they will no longer send patients to [GOSH] for second opinions because they are worried that they will return with an unexpected rare condition diagnosis and consequent treatment plan”, the experts wrote in July 2015 to Dr Vinod Diwakar, GOSH’s then medical director.

Great Ormond Street then brought in more external doctors to review the care given to more than 300 patients.

In a briefing to NHS England and the Care Quality Commission in December 2016, the hospital admitted that some approaches had been “at the aggressive end of the spectrum” and “some patients were exposed to the risks of unnecessary invasive investigations, difficult food-exclusion diets and drugs with potentially serious side effects”.

It also said some children had in fact been suffering from reflux or constipation, reviewers believed some endoscopies were unnecessary and some children should have been observed before being put on strong anti-inflammatory drugs.

Anxiety about the gastroenterology service forced the hospital to stop accepting most new referrals in 2015. The restriction is still in place. A recent follow-up report from the RCPCH found that that suspension had created “utter chaos” for other hospitals, which then had to look after an influx of medically complex patients who would normally have gone to GOSH.

The Royal College report found that the hospital was making “good progress” towards changes experts recommended in 2015, but some children still had diagnostic tests after too few checks and some of the gastroenterology consultants had not accepted the need to change their practices.

In a statement, the hospital said: “This is an incredibly complex area of medicine where there are no agreed clinical guidelines. Within this context while we always strive to provide the best possible care, we have acknowledged that we haven’t always got this right. For that we are very sorry.”

It added that experts believe the vast majority of care was good and there was no evidence of long-term consequences for any patients.

• Great Ormond Street: the Child First and Always? will be broadcast on ITV on Wednesday 18 April at 10.40pm.

