Severe diarrhea in a neonate or infant may be due to a common or rare inherited disorder.


Common causes of diarrhea:

(1) infection

(2) toxic exposure

(3) food allergy


Features of hereditary forms:

(1) family history

(2) early onset and persistent

(3) persistent despite bowel rest

Rare Causes of Intractable Diarrhea


Tricho-Hepato-Enteric (THE) syndrome (syndromic or phenotypic diarrhea)

facial dysmorphism, hair abnormalities

microvilllous atrophy (MVA), microvillous inclusion disease (MVID)

small bowel biopsy (PAS-positive granules, microvillous atrophy, abnormal enterocytes)

intestinal epithelial dysplasia (tufting enteropathy)

small bowel biopsy (disorganized surface enteroxytes with focal crowding that resembles tufts

congenital chloride diarrhea (CLD)

watery diarrhea with high chloride content

congenital sodium diarrhea (CSD)

watery diarrhea with high sodium and bicarbonate

glucose-galactose malabsorption (GGM)

ceases if glucose, galactose and lactose are removed from diet

autoimmune or immune-related enteropathy

may respond to immunosuppression or steroid therapy

mitochondria-related disorders




• Diarrhea in a family could be due to a hereditary cause, or shared exposure to infection or toxin.


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