Pope Francis remains in critical condition, with blood tests showing mild signs of kidney failure “which is currently under control,” the Vatican said Sunday, as the 88-year-old pontiff battles pneumonia in both his lungs.

The pontiff's condition is touch-and-go, given his age, fragility and pre-existing lung disease, according to doctors.

ROME -- Pope Francis was resting Monday morning after a quiet night, on the 10th day of his hospitalization for a complex lung infection that has provoked the early stages of kidney failure, the Vatican said. The one-line statement didn’t say if Francis, 88, had woken up. “The night passed well, the pope slept and is resting,” it said.