Nelson Mandela has gallstone surgery. Via Newsday

JOHANNESBURG - Nelson Mandela underwent successful surgery to remove gallstones yesterday, the office of President Jacob Zuma said, as the 94-year-old anti-apartheid icon recovers from a lung infection.
Doctors treating Mandela, South Africa's first democratically elected president, had waited to perform the endoscopic surgery to attend first to his lung ailment, presidential spokesman Mac Maharaj said.

In the gallstone procedure, a patient usually receives sedatives and an anesthetic to allow a surgeon to put an endoscope down the throat. The stones, small, crystal-like masses that can cause tremendous pain, can then be removed.

"The procedure was successful and Madiba is recovering," Maharaj said, using Mandela's clan name as many do as a sign of affection.

Occasionally, the procedure may also require removal of the gallbladder, medical experts say. Maharaj's statement offered no other details, however, about what additional care Mandela may require. Mandela was admitted Dec. 8 to a hospital in Pretoria.

The Nobel laureate has a history of lung problems, falling ill with tuberculosis in 1988 near the end of his 27 years in prison, before his release and subsequent presidency. While doctors said at the time the disease caused no permanent damage to his lungs, medical experts say tuberculosis can cause problems years later