Archbishop Desmond Tutu was readmitted to a South African hospital over the weekend, his family told CNN.
The 84-year-old was showing signs of an infection following a surgery he had just days ago.
After a three week stay in a Cape Town hospital, the Nobel laureate left last Wednesday.
He was first admitted to treat a recurring infection and had a minor surgery for the issue.
What forced Tutu to return to the hospital, according to his wife Leah, was that the surgical wound itself was showing signs of infection.
Tutu was also tested for a persistent infection in 2013. In 2014 he cancelled travel plans following his battle with prostate cancer, which was first diagnosed in 1997.
Tutu is the first black archbishop of Cape Town. He received the Nobel Peace Prize in 1984 for his work in ending apartheid.