CD55 is a regulatory membrane protein of the complement system which has been suggested as a marker for the prediction of enteral nutrition associated diarrhoea. Xie et al. 2020 found CD55 to be significantly reduced in patients with severe diarrhoea receiving enteral feeding.
References:
Xie Y, Tian R, Wang T, Jin W, Hou Y, Zhou Z, Wang R. A prediction model of enteral nutrition complicated with severe diarrhea in ICU patients based on CD55. Ann Palliat Med. 2021 Feb;10(2):1610-1619.