LONDON – Almost a fifth of “medical tourists” have suffered problems after travelling abroad for treatment, according to consumer group Which?

A growing number of Britons are choosing to travel abroad for surgery, attracted by big cost savings, but 18 percent of them concede the experience was problematic.

They included a tummy tuck patient who ended up with septicaemia and a liposuction patient whose stomach wound up “leaking cellulite”.

More than a quarter said they did not receive the necessary follow-up care and 8 percent were forced to turn to the National Health Service for emergency help when they got home.

A Which? mystery shopper survey also uncovered poor sales practices.

One researcher was told that a knee replacement operation was risk-free and would not require medical follow-up treatment. In reality, half of patients need physiotherapy and all cases need to be reviewed.

“Unprepared patients may find themselves on NHS waiting lists for vital physiotherapy or seeing a doctor who’s reluctant to follow up unknown work,” said Stephen Cannon, an orthopaedic consultant and Which? expert.

Around 80,000 Britons were “medical tourists” in 2006 and that figure rose to an estimated 100,000 last year, according to the Web site.

The savings can be significant. For example, a dental implant can cost 2,200 pounds in the UK, but as little as 750 pounds in Hungary, while a tummy tuck in Poland could be around half the British price of 4,000 pounds.

But Which? urges potential medical tourists to check doctors’ qualifications and registration with a professional body and to remember that legal rights differ across countries.

Editor Neil Fowler said: “Medical tourists must do their homework before jumping on the plane — and avoid rushing back too quickly — if they want to avoid potential problems.

“Ask the right questions beforehand, speak to UK health professionals and don’t assume you’ll have a safety net if things don’t go according to plan.”

Which? surveyed 300 Britons who had received treatment abroad in the past five years, and called 10 companies offering treatment abroad.