The bill for translating medical diagnoses to non-English speakers at doctors' surgeries and clinics has doubled since 2003.

Kingston Primary Care Trust (PCT) has spent £176,000 over the past five years and is set to spend another £50,000 next year.

The figures shed light on the numbers of people using the NHS locally who do not speak English as their first language.

Sandra O'Hagan associate director of public health at Kingston PCT described the service as an "equality" issue.

She said: "It is about equality of access of service. Previously, a lot of non-English patients would be taking relatives and friends along to be translators, which evidently can be open to lots of misinterpretations from the family's point of view. That is a service we must provide and continue to provide."

Dialects from the mountains of Afghanistan to the deserts of Somalia have needed interpretation.

Interpreters have changed medical jargon into 42 different languages, with 1,204 face-to-face interviews and 44 telephone interviews.

The diverse languages include Amharic, Somali, Ewe, Pashto, Krio and Dari as well as French, German and Spanish.

Deaf or hard of hearing people have been assisted by interpreters 17 times, using British sign language to make sense of medical jargon.

The PCT has also paid for translated audio taping and NHS documents as well.

Ms O'Hagan could not put a finger on why the budget had increased at such a rate.

She said: "We don't know if there is an increase in people getting interpreters or more aware of it because we have a better service.

"We are committed to it and that is why we have increased investment over the years."

Rebecca Mear, director of Refugee Action Kingston, said the service was invaluable for her clients because Government cuts in English language learning courses had deprived them of a chance to learn.

She said: "Despite the fact that many people are determined to learn English, it may not be enough to fully comprehend important information.

"My impression is it is only the people who really need it use it. It would be tied with lack of education in their own country or mental health issues or the trauma of coming here."