Even if frank manifestations of colitis are absent, inflammatory changes in the colonic mucosa are encountered frequently. The infant usually is dehydrated, and sometimes signs of malabsorption appear. Small bowel atrophy has been documented in different studies. The degree of villous atrophy can be similar to that of celiac disease. The mucosal damage causes malabsorption, hypoalbuminemia, and failure to thrive.
Some infants can present because of red blood mixed in stools.
These infants usually appear healthy, and hematochezia is the only complaint. In case of proctocolitis, the infant usually appears healthy, with normal weight gain. Genistein is a potent inhibitor of tyrosine kinases and can interfere with signal transduction pathways. Moreover, the volume intake of these products is sufficient to account for a significant high dietary intake of isoflavones. At the moment, very limited human data are available.