P853 Amoebic colitis mimicking inflammatory bowel disease: a report of four cases

Abstract

Background Amoebic colitis, caused by Entamoeba histolytica is an emerging diagnostic challenge for gastroenterologists in developed countries. Due to the similarity of symptoms and endoscopic findings, it can be easily misdiagnosed as inflammatory bowel disease (IBD) with a potentially devastating outcome especially if patient receives immunosuppression. The aim of this study is to look into the misdiagnosed cases to identify the challenges in differentiating amoebic colitis from IBD and to outline strategies to avoid this Methods Clinical and electronic case notes for the 4 patients, who were misdiagnosed as IBD between September 2015 to February 2019 at University Hospitals of Leicester U.K. were reviewed. The histology of resected colon specimens and endoscopic colonic biopsies were re-reviewed specifically for amoebic trophozoites. Results Three were male and 1 female. 1 patient was Caucasian while 3 patients were British Asian. Their mean age was 47.75 years (range 28–71). 3 cases were new IBD presentations while 1 patient was misdiagnosed as IBD since 2015. Two patients had a travel history to India and travelled to South East Asia 12 months prior to presentation. The travel history for 1 patient was not available. All 4 cases presented with bloody diarrhoea and had an endoscopic examination around the time of diagnosis which suggested acute inflammation likely IBD. Three were treated as ulcerative colitis while 1 patient was treated as Crohn’s disease. One patient required rescue therapy with cyclosporin while on intravenous steroids. As clinical symptoms worsened with rescue therapy, the patient required a subtotal colectomy. Similarly the patient who was treated for Crohn’s disease with Azathioprine and intravenous steroids, required subtotal colectomy due to recurrent flare ups. The other two cases were successfully treated with antimicrobial after the diagnosis of amoebic colitis although one of them received adalimumab prior to the correct diagnosis. The diagnosis of amoebic colitis was made through histological examination of the resected colon in 2 patients, colonic biopsy in 1 patient and stool E. histolytica DNA polymerase chain reaction (PCR) in 1 patient. Conclusion All 4 cases who were misdiagnosed as IBD had the diagnostic challenge of differentiating IBD from amoebic colitis due to similarity of symptoms and the endoscopic findings. Travel history is an important clue and should be considered for any patient presenting with colitis. New local guidelines were introduced to screen all patient with colitis for E. histolytica with serology and stool PCR. Patients requiring immunosuppression for suspected IBD are commenced on antimicrobial cover until E. histolytica results are available.

Amoebic colitis: A case series of a recurring missed diagnosis

“…8 Finally, Tufail et al described a case series of amoebic colitis in the United Kingdom masquerading as IBD. 9 Guidelines were suggested by the authors to screen for E. histolytica in all patients presenting with colitis, with amoebic antimicrobial cover to be empirically commenced in patients receiving immunosuppression until results are available. 9 The Australian Therapeutic Guidelines recommend treatment of acute amoebic colitis (dysentery) using metronidazole 600 mg orally every eight hours for seven days.…”

“…Finally, Tufail et al . described a case series of amoebic colitis in the United Kingdom masquerading as IBD 9 . Guidelines were suggested by the authors to screen for E. histolytica in all patients presenting with colitis, with amoebic antimicrobial cover to be empirically commenced in patients receiving immunosuppression until results are available 9 …”