James also spent time in hospital in 2007 following abdominal surgery

Blues legend Etta James is being treated in hospital in California after suffering from various ailments, including a blood infection.

"She's been in a pretty big battle," her son Donto James told Reuters. The singer has been in hospital for a week.

Mr James said his mother, 72, became ill while in a detoxification clinic for treatment to an addiction to painkillers and other medicines.

The R&B star is probably best known for 1961 ballad, At Last.

Beyonce sang the track at President Barack Obama's inaugural ball last year.

Hall of fame

James is being treated for a number of problems including the blood infection sepsis, believed to have started with a urinary tract infection, her son said.

Mr James said his mother was also suffering from speech difficulties, the cause of which is still being investigated.

He said doctors at the Riverside hospital were hoping to discharge his mother "very soon" and she would be moved to a nursing home for follow-up care.

Discovered by legendary band leader Johnny Otis, James's career has spanned five decades.

The singer developed a heroin addiction in the 1960s that was to last for more than a decade, and saw her spend time in a psychiatric hospital.

After kicking her drug habit, she remained a popular concert performer - although further chart success largely eluded her.

She was inducted into the US Rock and Roll Hall of Fame in 1993, and won the first of three Grammy awards for 1994's Mystery Lady: The Songs of Billie Holiday.

A year later, she scored a top 10 hit in the UK when her version of I Just Wanna Make Love To You was featured in an advertisement for Coca-Cola.

In 2007, the singer spent several weeks in hospital after suffering complications during abdominal surgery in Los Angeles.