Lethal multiple colon necrosis and perforation due to fulminant amoebic colitis: a surgical case report and literature review

Abstract

Background: Amoebiasis caused by the protozoan species Entamoeba histolytica rarely develops into fulminant amoebic colitis (FAC), but when it does, it shows an aggressive clinical course including colonic perforation, necrotizing colitis, and high mortality. Surgical treatment for FAC patients should be carried out urgently. However, even after surgery, the mortality rate can be 40-50%. Although FAC is one of the most unfavorable surgical diseases with a poor prognosis, there are a few reports on the perioperative diagnosis and management of FAC based on autopsy findings. We herein report the surgical case of a 64-year-old man who developed multiple colon necrosis and perforation due to FAC. A detailed autopsy revealed FAC as the cause of death. Additionally, we reviewed the existing literature on FAC patients who underwent surgery and followed their perioperative diagnosis and management.

Case presentation: A 64-year-old man presented with anorexia, diarrhea, and altered consciousness on arrival to our hospital. Computed tomography revealed a large mass in the upper right lobe of his lung, and the patient was admitted for close investigation. Bloody diarrhea, lower abdominal pain, and hypotension were observed soon after admission. Urgent abdominal contrast-enhanced computed tomography scan revealed extensive intestinal ischemia, intestinal pneumatosis, and free intra-abdominal gas. The preoperative diagnosis was bowel necrosis and perforation with intussusception of the small intestinal tumor. Emergency subtotal colectomy and enterectomy were performed soon after the contrast-enhanced computed tomography. He was taken to an intensive care unit after surgery. However, he could not recover from sepsis and died with disseminated intravascular coagulation and multiple organ failure on the 10th-day post-surgery. A histopathological examination of the resected colon showed transmural necrosis and massive amoebae invasion. He was diagnosed with FAC. An autopsy revealed that he had developed pulmonary large cell carcinoma with small intestinal metastasis. The death was caused by intestinal ischemia, necrosis and the perforation of the residual bowel caused by amoebae invasion.

Conclusions: Since FAC is a lethal disease with a high mortality rate and antibiotic therapies except metronidazole are ineffective, preoperative serological testing and perioperative metronidazole therapy in FAC patients can dramatically improve their survival rates.

Keywords: Bowel perforation; Colectomy; Fulminant amoebic colitis; Intestinal necrosis; Metronidazole; Serological testing.

Fig. 1

Computed tomography findings. a Intestinal ischemia was noted in almost all intestinal tracts. Extensive free intra-abdominal gas was noted in the upper and lower abdomen (arrowheads). Intestinal pneumatosis and intussusception of the small intestinal tumor were noted in the right lower abdomen (circle). b A large mass was found in the upper right lobe of patient’s lung (circle)

Fig. 2

Intraoperative findings. a A jejunal tumor telescoped inside of the oral jejunum which caused intussusception. b The jejunum had necrotic or ischemic change. c The transverse colon had necrotic or ischemic change

Fig. 3

Findings in the resected specimen. In this figure, the first and second intestinal tracts, from the top, correspond to the resected jejunum and part of the ileum. The small intestinal tumor was found in the oral side of the resected jejunum (circle). The third intestinal tract from the top represents the resected transverse colon and descending colon. The fourth intestinal tract from the top is the resected sigmoid colon. The dark-red colored segments of resected specimens showed ischemic changes. Particularly, the resected white colored segment of colon had multiple necroses with ulceration

Fig. 4

Histopathological findings in the resected colon. Massive amoebae invasion was observed using periodic acid–Schiff stains

Fig. 5

Autopsy findings in the residual bowel. Amoebae invasion was observed in the residual ileum (a) and rectum (b) using periodic acid–Schiff stains