PEOPLE with diabetes have been warned to check if they have a faulty blood glucose meter at home that could give a false reading and delay treatment.

Around 22,000 people are thought to be using either of two models of the OneTouch Verio meter that have a fault.

It causes them to either switch off or give a false low reading if the blood glucose level is extremely high, the Medicines and Healthcare products Regulatory Agency (MHRA) said.

Manufacturer LifeScan, which has a major research and development base in Inverness, has recalled the OneTouch Verio Pro with serial numbers starting with RA, RB, RC, RD or RE and the OneTouch Verio IQ with serial numbers starting with TA or TB.

The problem also affects all OneTouch Verio meters used only in healthcare settings, which have been alerted, the MHRA said.

It said the fault could mean diagnosis and treatment are delayed.

MHRA director of medical devices, John Wilkinson, said: "Extremely high blood glucose levels in people are rare, but if they do occur the person will require immediate medical attention.

"Protecting public health is our priority. If you have a Lifescan OneTouch Verio blood glucose meter, please phone LifeScan on 0800 279 9118."

More than one-quarter of a million Scots have diabetes and thousands use blood glucose meters daily to manage their condition. If blood glucose levels are not monitored carefully, patients risk suffering a number of complications such as damage to organs and eye disease.

Diabetes UK, the charity which supports people affected by the condition, has issued an alert on its website.

It said: "At extremely high blood glucose levels of 56.8 mmol/l and above, the meters do not operate as intended. This could lead to incorrect treatment or delay proper treatment of extreme hyperglycaemia, potentially resulting in serious injury.

"While the likelihood of experiencing an extremely high blood glucose level of 56.8 mmol/l or higher is rare, when such a blood glucose level occurs, it is a serious health risk requiring immediate medical attention."

Diabetes UK spokesman Simon O'Neill added: "People using these meters should contact the manufacturer. If they are concerned about their readings they should consult with their diabetes care team."

Patients using the meters can contact LifeScan, which will provide a replacement free of charge. OneTouch Verio strips and other models of LifeScan meters are not affected.

LifeScan is a world leader in blood glucose monitoring and is one of the biggest private employers in the Highlands, with around 1100 staff in Inverness.

In June last year First Minister Alex Salmond announced the city was to be the company's new home for all diabetes research and development into blood glucose monitoring.