Microscopic ileitis in diverted and nondiverted enteric segments: an underrecognized condition with a multifactorial etiology.
Microscopic ileitis has been infrequently reported in the literature with the few reported cases usually associated with concurrent microscopic colitis. Having encountered a case of collagenous ileitis involving the diverted distal limb of a loop ileostomy and sparing the proximal limb, we examined additional cases of loop ileostomy, end ileostomy, colostomy, and the accompanying diverted colorectal segment for features of microscopic ileitis and colitis. A total of 101 cases of diverted and nondiverted enteric segments were examined from 37 loop ileostomies, 16 end ileostomies, and 12 colostomies status post-Hartmann's procedure. The patients' clinical histories, including demographics and risk factors for microscopic colitis, were obtained from electronic medical records. The index case and an additional case showed collagenous ileitis: the former in the diverted distal limb, and the latter in the nondiverted proximal limb of the loop ileostomy. The latter was associated with high ileostomy output with watery diarrhea. Two additional cases showed lymphocytic ileitis: one in the nondiverted proximal limb of loop ileostomy and the other in the end ileostomy. All 4 patients had one or more risk factors for microscopic colitis. The etiology of microscopic ileitis seems to be multifactorial, and microscopic ileitis may be underdiagnosed. The diverted enteric segment may be involved by microscopic enteritis, suggesting that additional factors other than fecal stasis and altered bacterial flora may be contributing to its pathogenesis. When microscopic ileitis is encountered, identifying associated risk factors, recognizing incipient clinical symptoms of microscopic colitis, and considering other associated diseases or conditions are warranted.
['Zuo|Chunlai|C|', 'Fu|Zhiyan|Z|', 'Lee|Edward C|EC|', 'Foulke|Llewellyn|L|', 'Young|Gloria Q|GQ|', 'Cubero Rego|David|D|', 'Lee|Hwajeong|H|']
D000293:Adolescent D000328:Adult D000368:Aged D002648:Child D002675:Child, Preschool D003092:Colitis D003125:Colostomy D003967:Diarrhea D005260:Female D006801:Humans D007079:Ileitis D007081:Ileostomy D007223:Infant D007231:Infant, Newborn D007421:Intestine, Small D008297:Male D008875:Middle Aged D011183:Postoperative Complications D055815:Young Adult
Collagenous Ileitis Ileostomy Colostomy Lymphocytic Ileitis Diversion High Ostomy Output