Conversation: The conversation between human and AI assistant.
[|Human|] My 97 year old father is basically healthy & well-functioning.  However his hemoglobin levels keep dropping.  The doctor(s) put him in hospital for a blood transfusion or 2 or 3 and it drops again.  What type of doctor is best to consult with?  He has a primary care, hematologist, oncologist, radiologist, cardiac .. he appears to be leaking blood probably in the upper GI tract.   What field of medicine is best for another opinion?
[|AI|]  Hello and welcome to Chat Doctor, Fall in hemoglobin can occur in a number of conditions. Gastrointestinal tract is a very common site of bleeding and thus fall in hemoglobin. Blood loss can occur in cases of ulcers, polyps, or growths. In elderly there is increased risk of development of malignant tumors. Thus, as first line investigation, complete hologram and peripheral blood smear examination should be done. In addition, stool for occult blood should also be done. Presence of occult blood in stools suggests bleeding from gastrointestinal tract and thus requires colonoscopy for further assessment. Thanks and take care Chat Doctor.