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.

Pope Francis slept comfortably without additional complications but remained in critical condition with kidney and respiratory issues, the Vatican said Monday morning.

ROME — Pope Francis remained in critical condition Sunday and blood tests show early kidney failure but he remains alert and “well-oriented,” and attended Mass, the Vatican said, as the 88-year-old pontiff battles pneumonia and a complex lung infection.