Weight loss and continued diarrhea is of concern.
I am glad that his colonoscopy was normal. I am
assuming they also did a biopsy at that time.
There is a condition called "Microscopic Colitis" and
can only be diagnosed with a biopsy.
Irritable Bowel Syndrome
is associated with bloating,
and diarrhea.Weight loss is not.
Heavy alcohol abuse
can affect the liver but it can also
damage the pancreas.If he has chronic pancreatitis
repeated inflammation,he could have enzyme deficiency
that causes malabsorption
of nutrients.Usually the stoopl
is fatty,greasy,foamy and floats in the toilet bowl.
Low white cell count is also of concern.
He needs to have a complete set of blood tests including
Celiac panel,thyroid tests,upper GI and small bowel
X-rays to rule out Crohn's disease.
Hope with thos information, you can discuss with your
Wish him well.