Mr. S experienced abdominal pain and diarrhea, common symptoms of Crohn's disease involving his distal ileum and colon. Laboratory tests showed low albumin and prealbumin, indicating inflammation from IBD and insufficient protein intake. If he develops short bowel syndrome after surgery, recommended nutrition would include 6-10 mini meals per day with increased glutamine, normal macronutrient balance, and supplements if needed. His post-op energy and protein needs are 109.8g and 1820kcal but protein levels may need decreasing when eating solid food again unless labs still show low prealbumin.