Aim of this prospective, parallel multi-arm, randomized, clinical trial, was to compare the clinical outcome of patients Methods.We recruited children who undergone diagnostic colonoscopy in Umberto I Pediatric Department (Rome, Italy) from 2008 to 2010. Eligibility criteria were: 1) only demonstration of LNH; 2) no concomitant disease; 3) no treatment assumed since the clinical onset. Patients were allocated 1:1:1 to dietetic (Group A) vs mesalamine (Group B) vs no treatment (Group C) for a 8-weeks period. Skin prick tests and patch test for common foods, and symptoms scoring at baseline and follow up have been performed by blinded clinicians. Chi-square test for trend was used to compare the frequency of symptoms score improvement (>1 point) among groups. The association of baseline features of patients with the clinical response was estimated by frequency analysis.

Lymphoid nodular hyperplasia (LNH) of the lower gastrointestinal tract is a common finding in pediatric colonoscopies, whose clinical significance is not yet been clearly established. Although initially considered to be a normal, age-related variant, some authors recently suggested to regard LNH as a marker of food allergy (FA).

Inclusion Criteria:

1. isolated finding of LNH[18], defined as the demonstration of a significant cluster of lymphoid nodules (>10/visible field) by endoscopy and lymphoid follicle hyperplasia by hystology;
2. negative results of preliminary evaluation

Exclusion Criteria:

1. diagnosis of concomitant inflammatory, rheumatic or infectious disease, and
2. the assumption of any dietetic or therapy since the clinical onset.