You see a 45-year-old woman 3 years after small bowel resection related to MVA with trauma to the abdomen. What do her presenting symptoms suggest?
A 45-year-old woman presents with a history of small bowel resection after a motor vehicle accident with steering wheel trauma to the abdomen. For the past 3 years she has experienced bloating, diarrhea, and diffuse abdominal pain. Results of celiac testing, thyroid function testing, and infectious pathogen stool studies were negative; CT enterography demonstrates dilated loops of bowel without obstruction.
Answer: D. Decreased serum vitamin B12. Risk factors for small intestinal bacterial overgrowth (SIBO) include surgically altered anatomy, Crohn disease, and poorly controlled diabetes. Intestinal stasis and bowel dilation are implicated in bacterial overgrowth. Enteric bacteria compete with the host for nutrients, including vitamin B12, iron, and thiamine. This results in vitamin B12 and thiamine deficiency. Folate and vitamin K levels are typically normal or increased in SIBO; iron deficiency can also be seen in SIBO.