Partial enteral nutrition has no benefit on bone health but improves growth in paediatric patients with quiescent or mild Crohn's disease

Background and aims: Exclusive enteral nutrition induces remission, improves bone health and growth in paediatric Crohn's disease (CD) patients, but is highly demanding for patients. We investigated efficacy of partial enteral nutrition (PEN) on bone health, growth and course in CD patients and assessed microbial and metabolic changes induced by PEN. Methods: We performed a two centre, non-randomized controlled intervention study in quiescent CD patients aged <19 years. Patients in intervention group received a liquid formula providing ~25% of daily energy for one year. At baseline, after 3, 6, 9 and 12 months, we collected data on bone, muscle (peripheral quantitative computertomography), anthropometry, disease activity (weighted paediatric CD activity index), metabolomic profile (liquid chromatography mass spectrometry), and faecal microbiome (16S rRNA gene sequencing). Results: Of 41 CD patients, 22 received the intervention (PEN) (mean age 15.0 ± 1.9 years, 50% male), 19 served as controls (non-PEN) (12.8 ± 3.1 years, 58% male). At baseline, mean bone quality was comparable to reference population with no improvement during the intervention. Relapse rate was low (8/41, PEN 4/22 and non-PEN 4/19, ns). PEN was not associated with microbiota community changes (beta diversity) but significantly reduced species diversity. Metabolome changes with upregulation of phosphatidylcholines in PEN patients are likely related to lipid and fatty acid composition of the formula. PEN significantly improved growth in a subgroup with Tanner stage 1–3. Conclusion: In our cohort of paediatric CD patients, PEN did not affect bone health but improved growth in patients with a potential to grow.