Cardinal Francis George is spending his fourth night at Loyola Medical Center in Maywood Monday with the flu.
NBC 5 has learned George was admitted to the hospital suffering from dehydration on Friday.
Archdiocese spokesperson Colleen Dolan says the decision to hospitalize George was made out of an abundance of caution for two reasons -- to receive intravenous fluids and antibiotics so he could make a full recovery, and because of the new round of chemotherapy he just started to treat an aggressive form of cancer in his right kidney.
Dolan says there is no reason to be alarmed, and that he's in "good spirits and feels good."
George, 77, was forced to cancel his public appearances and travel schedule, including an eagerly-anticipated trip this week to the Diocese he once led in Yakima, Washington, where he was scheduled to bless a gymnasium named in his honor.
George is expected to return home from the hospital sometime this week.