Many who know him said that Francis, driven by a sense of mission and a discipline born of his early training, essentially worked himself into the hospital.

Pope Francis, 88, was hospitalized last Friday with bronchitis, the Vatican said, and now has a “polymicrobial infection of the respiratory tract.”

The Vatican said Pope Francis has the "onset of bilateral pneumonia," and that tests, a chest X-ray and the pope's clinical condition present a "complex picture."