I checked snopes a googled all i could and I can't find anything that reports this as fake or a hoax.
Still not convinced though. Perisalsis should have forced all the feces in her lower intestines into her colon. Then if it sat there for a week she should have developed what is called a 'fecal impaction'. All the fiber and such would have actuallly furthered this process of fecal impaction (which has to be removed surgically).
However, IF this is real... That woman/man is my new personal hero.
One Love,
SFW