BUENOS AIRES, Argentina (October 2, 2009)--Argentine folk singer Mercedes Sosa's health is deteriorating further at the Buenos Aires clinic where she is in critical condition, doctors said.

The Trinidad Clinic said Sosa is in a "pharmacological coma and breathing with a respirator."

According to a statement issued Friday, her prognosis has "worsened in the last 24 hours."

Sosa, 74, entered the hospital 13 days ago for liver problems.

She has since been suffering from progressive kidney failure and cardiac arrest.

Sosa has recorded more than 70 albums and is best known for her signature song "Gracias a la vida," or "Thanks to Life."

Her latest record, "Cantora 1," is up for three Latin Grammy awards next month in Las Vegas.