After the third time he nearly died but before the fourth, David Fajgenbaum embraced a new motto: Think it, do it. "I got out of the hospital with this profound sense of, you need to make the most of every second," he says. A former college football player with close-cropped dark hair and a firm handshake, Fajgenbaum, 31, is the picture of youthful vigor now. But that belies a frightening reality. Tomorrow the symptoms with which he's all too familiar could return, sending him to the intensive care unit (ICU) with every organ failing.
