Prospective Study on the Safety of the Postbiotic Lactobacillus LB (Lactéol®) in Immuocompromised Pediatric Patients With Diarrhoeal Disease Treated at the Federico Gómez Children's Hospital of Mexico.

This prospective, interventional, single-center, open-label, phase 1 clinical trial to assess the safety of the Postbiotic Lactobacillus LB in immunocompromised paediatric patients with diarrhoeal disease will be performed at Federico Gomez Children's Hospital of México. Patients will be screened by investigators from hospitalized patients. For eligible children, parents will be invited to participate in the study and provide written consent, in patients of age 8 years and older, informed assent will also be required. Once enrolled, patients' demographic and stratification information will be obtained from the clinical record when applicable, if not, it will be directly collected by the investigator. Patients who have immunocompromise, as per investigator assessment, irrespective of the cause, will receive Lactobacillus LB (Lactéol®) sachets twice daily for 14 days for patients with acute diarrhoeal disease (<72 hours of onset) and for 28 days for patients with chronic diarrhoea (≥15 days). Patients will continue follow-up while receiving treatment in hospital, whereas patients who are discharged during the treatment period will continue follow-up via phone calls once weekly and a final evaluation of outcome variables in outpatient clinic at the end of the intervention. Data regarding adverse events, as well as the stop of diarrhoea (<3 bowel movements in 24 hours or return to habitual bowel movement frequency) and improvement in stool consistency (at least one point decrease in Bristol Stool Scale) will be collected in every evaluation. Afterwards, the presence or absence of adverse events will be established with a binomial test. As efficacy evaluation is not the main objective of the study, efficacy will be assessed as exploratory variables as presence or absence of efficacy endpoints with the binomial test. If feasible, results may be stratified according to nutritional status, time of onset of diarrhoea, and treatment compliance.