Inclusion Criteria: children and adolescents from 0 to 19 years old, with lesion in the gastric mucosa regardless of size, hospitalized or undergoing treatment at the Renal Replacement Therapy Unit, who do not present contraindications for phototherapy and who accept to participate in the proposed treatment from the signing of the Age-appropriate consent form and the legal guardian's consent form.  Exclusion Criteria: patients with infection at the application site, with photosensitivity or hypersensitivity caused by laser radiation, with a pacemaker or other electronic implant, patients with malignant lesions or undiagnosed lesion on the area of the stoma to be irradiated, patients and / or legal guardian who does not accept to participate.