Pope Francis remained in critical condition Monday but showed slight improvement in laboratory tests and resumed some work, the Vatican said, including calling a parish in Gaza City that he has kept in touch with since the war there began.

Officials said Pope Francis is in critical condition as he battles pneumonia and early kidney failure. He was awake and eating normally during his treatments. Crowds have been gathering at Vatican City to pray for his recovery. Doctors reported Sunday that blood tests showed his early kidney failure was under control.

Francis was also given blood transfusions, according to the Vatican, after blood tests revealed he was suffering from thrombocytopenia, meaning the platelet count in his blood was too low, a condition the doctors said is associated with anemia. Infections and medical treatment may lower platelet count.