Teaching Case

A 73-year-old male presented to our ED with acute abdominal pain along with symptoms of fever and vomiting. Physical examination revealed abdominal tenderness at the right lower quadrant with guarding and rebound. Blood investigations revealed markedly elevated white cell count (13,640cells/μL) and deranged renal function.

Subsequently, he underwent a CT scan of the abdomen without intravenous contrast agent, due to elevated serum creatinine. His abdominal non- contrast CT revealed asymmetrical thickening of the cecal wall with air layers (Figure1).  Pericolic fat stranding and free intraperitoneal fluid were also present (Figure 2). Additionally, CT demonstrated severe atherosclerotic changes of the aorta and the superior mesenteric artery and its terminal branches (Figure 3). Considering the possibility of Isolated cecal ischemia (ICI) the patient underwent immediately an exploratory laparotomy which revealed gangrene of the caecum and a right colectomy was performed (Figure 4). Conversely, the operative findings showed no visible evidence of major vascular occlusion or embolisation, while the appendix and the remainder of the intestine appeared normal. After the resection of the damaged intestine, extracorporeal end to end anastomosis was performed. Pathological examination of the specimen depicted ischemic necrosis of the caecum involving mucosa with focal necrosis. The patient recovered after surgery with uneventful postoperative course and was discharged home one month later.

Isolated cecal ischemia (ICI) represents an uncommon variety of bowel ischemia that affects most commonly the elderly population.  It has been proposed that the caecum, like the splenic flexure and the rectosigmoid, is a ‘watershed area’, regarding its blood supply [1]. The caecum is mainly supplied by the anterior and posterior cecal arteries. These are terminal branches which arise from the ileal or the colic branch of the ileocolic artery. Rist et al (2) suggested that the absence of a vascular arcade between the ileal and colic branches in some individuals makes the caecum vulnerable to ischemia. Moreover, it has been suggested that anatomic variations such as an absence of the posterior cecal artery may also play an important role in the pathogenesis of the ICI [2].

ICI typically presents with an abrupt onset of right-sided abdominal pain and rectal bleeding while diarrhea, leukocytosis and fever may also be present [3,4]. Due to it rarity and lack of pathognomonic clinical symptoms, ICI can pose a diagnostic dilemma. CT is the diagnostic modality of choice as it can distinguish ICI from other conditions with overlapping clinical presentations, such as acute appendicitis, allowing a more confident diagnosis. On CT, cecal infarction typically presents as isolated, circumferential thickening of the cecal wall, although this finding is non-specific [4]. A mural stratification pattern, associated with the ‘target sign’, reflects the presence of submucosal oedema in the bowel wall [5]. Intramural air has also been described in cases of ICI, such as in our case [6,5].  Perceval inflammation, stranding of the adjacent fat and pericolic fluid may also be commonly identified [4]. Other CT findings of ICI reported in the literature include focal or diffuse bowel dilatation, engorged mesentery and portal or mesenteric venous gas [5]. Pneumoperitoneum is an ominous CT sign as it indicates perforation of the infarcted bowel segment. 

ICI is a rare, but potentially life-threatening cause of acute right-sided abdominal pain with an ambiguous clinical presentation. Cecal ischemia should be included in the differential diagnosis of elderly patients presenting with acute right lowerquadrant pain, apart from acute appendicitis and bowel obustruction. CT should be used to exclude the presence of other more common and relevant causes of abdominal pain and to confirm the diagnosis. An early diagnosis and urgent resection of the damaged intestine are essential for the successful treatment and uneventful outcome of patients with ICI.