Songstress Amy Winehouse may have to pull out of Glastonbury and the Nelson Mandela concert amid fears she has emphysema.

Earlier reports suggested that she may have developed tuberculosis, but the singer's father Mitch Winehouse has come out as saying that she is experiencing symptoms associated with the chronic lung disease.

The troubled singer is booked to play at Mr Mandela's 90th birthday concert in Hyde Park on Friday June 27, followed by an appearance at Glastonbury, where she is due to perform immediately before headliner Jay-Z.

However, Winehouse, who has fought an addiction to heroin and crack cocaine, is still in a London clinic awaiting the results of tests following her collapse at home.

A spokesman said Winehouse still intends to perform at both high-profile events, but that doctors will decide whether she was well enough to take to the stage.

He said: "Amy has undergone more scans and tests today and we are awaiting the verdict of her doctors. At present, she still intends to perform at the two scheduled dates next week."

"However, a decision will be made entirely upon the advice of her doctors and in her best interests," he added.

Winehouse, 24, has been in the London clinic since being taken there by her father after fainting at her home in Camden, north London, last Monday.

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