What would cause lactoferrin stool test to be negative but stool calprotectin to be 230 ?

IBD: These are markers of inflammatory bowel disease although 20 % of people with simple irritable bowel syndrome may have elevated levels but under 250. These markers don't tell us what type of inflammatory bowel disease is present-only that real inflammation is present. In view of your negative lactoferrin and lowish calprotectin, you most likely don't have inflammatory bowel disease.