obsolete intractable diarrhea of infancy https://github.com/monarch-initiative/mondo/issues/5114 https://github.com/monarch-initiative/mondo/issues/6743 true OBSOLETE. Intractable diarrhea of infancy (IDI) is a heterogeneous syndrome that includes several diseases with different aetiologies. Provisional classification of IDI, according to villous atrophy and based on immunohistological criteria, distinguishes two clearly different groups of IDI: 1) Immune-mediated: characterized by a mononuclear cell infiltration of the lamina propria and considered as being related to T cell activation. 2) The second histological pattern includes early onset severe intractable diarrhea histologically characterized by villous atrophy with low or without mononuclear cell infiltration of the lamina propria but specific histological abnormalities involving the epithelium. IDI MONDO:0019126 Orphanet:73014