The Brazilian damaged knee cartilage while on international duty against Colombia last Friday, while Aurier sustained a head injury against Cameroon while representing the Ivory Coast.
And after returning to the French capital for medical tests, PSG remain in the dark of the duo's availability for their trip to Brittany this weekend.
A club statement read: "Following a left knee injury that occurred during the match between Brazil and Colombia, the evolution of the injury to David Luiz is favorable but persistent pain require further treatment before resuming training.
"Serge Aurier remained under observation last night with the Ivorian team in the aftermath of his head injury.
"Paris Saint-Germain is in constant contact with the player and the medical staff of the Ivorian team.
"He traveled to Abidjan where he spent a CT scan before returning to Paris for further examination."
