The study included 30 patients with gastroenteritis and pneumatosis intestinalis, seen at the pediatric hospital of the IMSS, who followed a satisfactory course. Complications and associated diseases were found in these patients to be less severe than in other patients who died. Lethality in this type of patients (33%) is analyzed together with the clinical records in 33 cases of death from gastroenteritis and pneumatosis intestinalis during the period from January 1974 to April 1975. It was found that the period of hospital stay was shorter than in the group that recovered; that complications leading to death were severe and of acute evolution among which, bronchopneumonia, septic shock, intestinal infarct and others, predominated. Decrease in lethality may be considered to lie in an earlier diagnosis together with prevention and treatment of pneumatosis intestinalis and its complications.