Polymeric versus elemental diet as primary treatment in active Crohn's disease: a randomized, double-blind trial

Enteral feeding is now an established primary therapy for active Crohn's disease. This first-double blind randomized trial was designed to compare the therapeutic efficacy of a polymeric diet (PD) with an elemental diet (ED).

Patients with active Crohn's disease (Crohn's disease activity index [CDAI] > 150, increased bowel uptake of Tc-HMPAO-labeled leukocytes, and abnormal C-reactive protein [CRP]), were randomized to receive either an ED or a PD. The two preparations were identical except for the nitrogen source, which was amino acid based in ED and intact protein in PD. Enteral feeding was considered successful if clinical remission was achieved as defined by a final CDAI of < or = 150, a reduction in the CDAI by at least 100 points from baseline level, and a normal CRP.

Twenty-one patients were enrolled of whom 11 were randomized to PD and 10 to ED. The two groups were comparable at entry. Clinical remission was obtained in eight (80%) patients receiving ED and six (55%) patients receiving PD, p = 0.1. The treatment failed in three and two patients in the PD and ED groups, respectively. Another two patients were intolerant to the feed (PD). Reduction in the CDAI after treatment with ED (359 +/- 67 to 112 +/- 19) was similar to that seen with PD (303 +/- 27 to 97 +/- 11). Similar changes in the CRP were also observed (16 +/- 5 to 4 +/- 1.6) and (62 +/- 20 to 9 +/- 6), respectively. Overall, enteral feeding was successful in 14 patients (63%).

Enteral nutrition is effective in treatment of active Crohn's disease. Differences in nitrogen sources of enteral feeds are not relevant to their therapeutic efficacy, as polymeric and elemental diets are equally effective.