A 70-year-old female presents with chronic diarrhea for the past three months. She has lost 10 pounds during this time and reports intermittent night sweats. She also reports a history of non-Hodgkin's lymphoma treated five years ago. Stool is watery with no visible blood. What could be the potential causes?
In this patient with a history of non-Hodgkin's lymphoma and symptoms of weight loss and night sweats, the recurrence of lymphoma involving the gastrointestinal tract should be considered. Another possible cause could be lymphocytic colitis, a type of microscopic colitis, which has been associated with lymphoproliferative disorders. She should undergo colonoscopy with biopsies and other necessary imaging to check for recurrence of lymphoma.