Intractable Diarrhea Of Infancy

Intractable diarrhea of infancy (IDI) is a heterogeneous syndrome that includes several diseases with different etiologies. Provisional classification of IDI, according to villous atrophy and based on immunohistological criteria, distinguishes two clearly different groups of IDI: 1) Immune-mediated: characterised 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 characterised by villous atrophy with low or without mononuclear cell infiltration of the lamina propria but specific histological abnormalities involving the epithelium.

Clinical description

Based on recent advances in the genetics of autoimmune enteropathy as well as the pathophysiology and clinical presentation, autoimmune enteropathy can be classified into three different types: the classical form of autoimmune enteropathy, identical to the so-called immune dysregulation-polyendocrinopathy-enteropathy-X-linked (IPEX) syndrome (autoimmune enteropathy type 1); autoimmune enteropathy type 2 (without extra-intestinal manifestations) and autoimmune enteropathy type 3 (in girls). Microvillus inclusion disease (MVID) and Intestinal epithelial dysplasia (IED), also known as tufting enteropathy, are congenital enteropathies presenting with villous atrophy and are thought to be related to abnormal enterocytes. Another form of IDI that should be considered in a different way from the two other groups is so-called 'phenotypic diarrhoea'' or 'syndromatic diarrhoea''. This form of IDI presents with severe early onset diarrhea resisting bowel rest, non-specific villous atrophy and very characteristic extra-digestive (facial and hair dysmorphy) manifestations.

Diagnostic methods

Clinically, IDI may be easy to diagnose on the basis of the symptoms onset, clinical presentation and associated disorders. Histopathological analysis confirms the diagnosis.

Prognosis

Infants with IDI remain dependent on parenteralnutrition for months, years and, in most cases, forever because of the permanent intestinal failure associated with the high rate of digestive loss. As long-term parenteral nutrition is associated with complications and/or poor quality of life, alternative treatments, such as intestinal transplantation, have to be considered.