Thanks for posting your query at DoctorSpring.com
I am Dr.R.K and I am pleased to assist you.
In about 5% of the cases the bleeding per rectum is from the upper GI source.
You have had lesions in the upper GI tract which was diagnosed way back in 2007.
I would advise you to get an upper GI scopy done again.
Your colonoscopy and stool test are normal.
If the upper GI endoscopy also does not reveal anything, then the next step is to explore the small bowel to look for lesions.
This can be either done with an enteroscopy or a capsule endoscopy.
As far as the abnormal liver function is concerned, the most common cause of raised ALT is fatty liver disease. But your CT scan shows a normal liver. I would advise you to get the liver function test repeated after 4 weeks, If the repeat liver function test also shows abnomal values, then further testing may be done.
You can discuss with your doctor about these things.
Let me know if I can assist you further.