How do you approach the decision to repeat small-bowel biopsies in a patient with persistent gastrointestinal symptoms, like abdominal pain and diarrhea, when prior biopsies performed years earlier were normal?”  

I typically do not repeat small bowel biopsies IF the symptoms have not changed in intensity or frequency. Repeat endoscopic evaluation and biopsies are done in patients with persistent GI symptoms if any changes have occured: these may include significant worsening of symptoms, of symptoms occur ...