She was booked into the Milpark Hospital in Johannesburg on Saturday, said spokesperson Victor Dlamini.
“Prior to going to the clinic, she was uncomfortable and complaining of loss of appetite and one of her legs was painful,” he said.
Dlamini said upon admission, it was discovered that Madikizela-Mandela had an infection that had affected her kidneys.
She is expected to make a full recovery.
Dlamini said she is likely to spend around a week in the hospital.
“She is constantly surrounded by family and is in high spirits. The family will keep the public informed of any developments.”