A charity has warned some hospitals are doing “more harm than good” to people with diabetes, after an audit suggested thousands of patients each year could be developing a life-threatening but preventable complication due to poor care.

Over a five-day period, 61 patients developed diabetic ketoacidosis during their hospital stay.

If the figures are extrapolated, it could mean that as many as 4,400 diabetic patients suffer from the condition while in hospital each year.

Charity Diabetes UK said it is “appalling” that any patients should develop the complication - which is caused by a shortage of insulin.

And a third of patients in hospitals in England and Wales experienced a “medication error” during the National Diabetes Inpatient Audit.

The audit, conducted by the Health and Social Care Information Centre, which examined data from 13,400 patients in September last year, also found that a fifth of patients suffered from hypoglycaemia while in hospital.

Bridget Turner, director of policy and care improvement at Diabetes UK, said: “It is appalling that some people with diabetes are being so poorly looked after in hospitals that they are being put at risk of dying of an entirely preventable life-threatening condition.

“Even a single case of diabetic ketoacidosis developing in hospital is unacceptable, because it suggests that insulin has been withheld from that person for some time.

“The fact that this is regularly happening raises serious questions about the ability of hospitals to provide even the most basic level of diabetes care.

“In every aspect of hospital diabetes care that this report shines a light on, the picture that emerges is profoundly disturbing.

“Medication errors are being made with alarming regularity, large numbers of people are not getting foot checks that we know can help prevent amputation, while one in 10 people’s blood glucose level is dropping dangerously low during their hospital stay.

“Put together, this adds up to a situation where, in too many cases, hospitals are doing people with diabetes more harm than good.”

Audit lead clinician Dr Gerry Rayman said: “The purpose of this annual audit is to drive improvements in care for inpatients with diabetes, so I am pleased to see there has been some progress on problems highlighted in previous years’ reports, for instance around insulin prescribing.

“But staffing levels remain low, and it is of grave concern that some patients are developing DKA, which is a potentially life-threatening complication, in hospital. This is due to their needs being neglected and should simply never happen.”