Now, to a frightening headline out of san francisco. A patient who disappeared from her hospital room, missing for 17 days, finally identified as the woman found dead this week in that hospital... See More
Now, to a frightening headline out of san francisco. A patient who disappeared from her hospital room, missing for 17 days, finally identified as the woman found dead this week in that hospital stairwell. Authorities are investigating how that happened. And abc's david wright has the story. Reporter: At san francisco general hospital, a medical mystery. A patient who checked in for a routine infection missing for more than two weeks. What happened at our hospital is horrible. Reporter: This week, that patient, 57-year-old lynn spaulding, turned up dead, in a hospital stairway. Hospital officials say they have no idea what happened. I'm committed to getting to the root cause of this tragedy. Reporter: After spaulding WENT MISSING SEPTEMBER 21st, TWO Days after she checked in, sheriff's deputies conducted an all-out search. Evidently, it wasn't a very good one. Reporter: Evidently, they missed the fourth story staircase where spaulding's body was found. The stairwell is a fire exit not routinely used by staff. Reporter: The medical examiner is trying to determine the cause and the timing of her death. We're here to take care of patients, to heal them. To keep them safe. This has shaken us to our core. Our staff is devastated. Reporter: A tragedy and a mystery at san francisco's biggest hospital. For "good morning america," david wright, abc news, los angeles.
This transcript has been automatically generated and may not be 100% accurate.