The effects of provocation by foods with raised IgG antibodies and additives on the course of Crohn's disease: a pilot study

This study was designed to assess the role of foods with raised IgG antibodies and additives on the symptoms and inflammation of Crohn's disease. Eight patients with Crohn's disease in remission were studied. They followed a strict diet during phase I. Then, provocations with two, three-day periods (phases II and III) followed: in phase II, pure forms of foods with high IgG antibodies and in phase III, off-the-shelf forms of those foods were added. Stool samples were collected for fecal calprotectin assay. Blood samples were taken on the 11th and 17th days for highly sensitive C-reactive protein, ferritin, erythrocyte sedimentation rate, white blood cells, and platelets. Patients kept a diet-symptom diary. Increased Crohn's disease activity index scores were found statistically significant (p=0.012) between pre- and during the provocation weeks. There were significant increases according to Harvey-Bradshaw Index when the highest values during the phases I, II (p=0.027) and I, III (p=0.027) were compared. The increases in highly sensitive C-reactive protein (p=0.025) and white blood cells (p= 0.036) were found statistically significant. Fecal calprotectin levels showed day-to-day variability. When compared, the levels of fecal calprotectin increased in all patients on the last day of the restriction (10th day) and the first day of the provocation (11th day) with the exception of one patient. Foods with raised IgG antibody levels and food additives can provoke the symptoms and may stimulate the inflammation in patients with Crohn's disease. Addition of a proper diet with restriction of those foods may be beneficial in the medical treatment.