Ulcerative colitis. White exudate is present overlying an abnormal colonic mucosa that has lost its typical vascular pattern. Source: Gastrointestinal Tract, CURRENT Diagnosis & Treatment Pediatrics, 23e Citation: Hay WW, Jr., Levin MJ, Deterding RR, Abzug MJ. CURRENT Diagnosis & Treatment Pediatrics, 23e; 2016 Available at: http://accessmedicine.mhmedical.com/DownloadImage.aspx?image=/data/books/1795/ped23_ch21_f008.png&sec=125743073&BookID=1795&ChapterSecID=125742582&imagename= Accessed: December 30, 2017 Copyright © 2017 McGraw-Hill Education. All rights reserved