Spontaneous Free Perforated Small Bowel (Jejunum) in Crohn Disease: A Case Report

Abstract

Abstract

Background:

Free perforation of the bowel in Crohn disease is one of the indications for emergency surgery. Spontaneous free perforation is an uncommon event and perforation of the small bowel (jejunum) is rare in Crohn disease. The present study reports a case of spontaneous free perforation of the jejunum in Crohn disease before diagnosis of Crohn disease.

Case Presentation:

A 24-year-old female presented with a one-month history of intermittent abdominal pain and diarrhea. She had severe abdominal pain and fever and visited the emergency department. An abdominal computed tomography (CT) scan showed small bowel perforation. Emergency exploratory laparotomy was performed. Jejunal perforation with inflammation was present and inflammation was also found intra-operatively at the long segment of the jejunum. Segmental resection was performed on the jejunum. Final pathology of the resected jejunum showed chronic transmural inflammation with ulcer, perforation, stricture, and lymphoid follicles, consistent with Crohn disease.

Crohn disease is a chronic, multi-systemic, lifelong disease that can affect any gastrointestinal site from the mouth to the anal canal. Crohn disease can cause progressive transmural inflammation of the mucosa at the affected gastrointestinal site. The etiology and pathophysiology of Crohn disease remain unknown [1]. Free perforation is one of the complications in Crohn disease that requires emergency surgery but the incidence is rare. Free perforation in Crohn disease is defined as a spontaneous perforation of the small or large bowel accompanied by the flow of the bowel contents into the peritoneal cavity. The incidence of free perforation in Crohn disease has been reported to be 1.0% to 2.0% in Western countries [2–4]. The incidence of free perforation in Crohn disease is also rare in Asian countries. While the incidence of Crohn disease remains lower in Asian countries than in Western countries, the incidence has been increasing recently [5]. Nevertheless, Crohn disease and free perforation of the small bowel in Crohn disease is rare in Asian countries. This case report presents the spontaneous solitary free perforation of the small bowel (jejunum) in Crohn disease in a Korean patient before diagnosis of Crohn disease.

Case Presentation

A 24-year-old female presented with a one-month history of intermittent abdominal pain and diarrhea. She had no history of medical disease or surgery. She visited the emergency department because of severe abdominal pain and fever. Laboratory testing revealed a white blood cell (WBC) count of 14,200 cells/mm³, C-reactive protein (CRP) of 4.12 mg/dL (reference range, 0–0.5 mg/dL), and hemoglobin count of 9.8 g/dL. The other laboratory tests were normal. She had fever (37.1°C), abdominal pain, and hypotension (systolic pressure, 80; diastolic pressure, 60). An abdominal pelvic computed tomography (CT) scan revealed pan-peritonitis caused by perforation of the small bowel loops (Fig. 1). An emergency exploratory laparotomy was performed. Jejunal perforation with inflammation was found intra-operatively, as well as inflammation at the long segment of the jejunum (Fig. 2). The lumen of the long segment of jejunum with inflammation was filled with a lymphoidal mass. Segmental resection of the perforated and inflamed jejunum was performed. A side-to-side anastomosis was performed using the staple technique. Final pathology reported chronic transmural inflammation with ulcer, perforation, stricture, and lymphoid follicles, consistent with Crohn disease (Fig. 3). The patient was discharged two weeks after surgery in good condition.

FIG. 1.

Abdomen pelvic computed tomography (CT) finding: pan-peritonitis caused by perforation of small bowel loops.

FIG. 2.

Intra-operative finding: perforation and inflammation of the jejunum.

FIG. 3.

(A) Resected small bowel: ulcerated mucosa and perforated wall, macroscopic (arrow). (B) Ulcerated mucosa and perforated wall, microscopic (arrow). (C) Chronic transmural inflammation. (D) Lymphoid follicle.

Discussion

The reported incidence and prevalence rates of Crohn disease are higher in Western countries than in Asian countries. However, those rates are increasing around the globe [5]. In Korea, the annual incidence rate of Crohn disease between 2001 and 2005 was reported to be 1.34 per 100,000 inhabitants compared with 0.05 per 100,000 inhabitants between 1986 and 1990 [6]. Disease location of Crohn disease is usually classified as L1 (terminal ileum), L2 (colon), or L3 (ileocolon) using the Montreal classification [7]. The most commonly involved site in Western countries is L2 (30%–40%) [8]. In contrast, in Korea the most common site is L3 (53%–71%), followed by L2 (21%–32%) and L2 (7%–14%) [9]. The disease behavior of Crohn disease is usually differentiated as inflammatory (B1), structuring (B2), or penetrating (B3). The proportion of disease behaviors is inflammatory (B1; 68.5%), structuring (B2; 14.4%), penetrating (B3; 17.1%), and active peri-anal fistula or a reported history of peri-anal fistula (21.3%) in Korea [9]. Free perforation of the small bowel in Crohn disease is a rare disease behavior, especially perforation of the jejunum rather than the ileum.

The incidence of free perforation in Crohn disease in a Korean study (Crohn's Disease Clinical Network and Cohort [CONNECT] study) was reported as 6.5% (n=88/1346) in 1982–2008. Among the cases of free perforation in Crohn disease, 52% of patients (n=46) had presenting signs associated with a diagnosis of Crohn disease [10]. The incidence of free perforation in Crohn disease in Japanese studies was reported as 1.5%–10.5% among patients with Crohn disease [11]. The site of the free perforation in the present case was the jejunum, which is also a rare perforation site. The more common sites of free perforation in Crohn disease involve the ileum (n=81/94; 86.2%), jejunum (n=6/94; 6.4%), and colon (n=7/94; 7.9%) as reported in the CONNECT Study [10]. The Japanese studies (1974–2002) reported only seven jejunal perforations (n=7/126), with higher rates of ileal perforations (n=102/126) and 17 colonic perforations (n=17/126) [11].

Usually, segmental resection is performed at the site of free perforation in Crohn disease. Post-operative complications of free perforation in Crohn disease are anastomotic leak, enterocutaneous fistula, wound dehiscence, wound infection, and prolonged ileus [12]. In the present case, segmental resection of the jejunum was performed, and the site showed infection on post-operative day 7. There were no other complications after surgery.

Risk factors associated with free perforation of Crohn disease are bowel stricture and age over 30 years when Crohn disease is diagnosed [10]. The CONNECT Study reported that bowel strictures were significantly more frequent in the free perforation group compared with the non-perforated group (40.9% versus 25.7%, p=0.001). Age older than 30 years when Crohn disease was diagnosed was also reported (p=0.002) as a risk factor in multivariable logistic regression analysis [10]. Steroids [13] and tumor necrosis factor (TNF) [14] have also been reported as risk factors associated with free perforation of Crohn disease. The mechanism of free perforation in Crohn disease is unknown, but two theories suggest that (1) increase in the intra-luminal pressure proximal to a stenosis causes bowel distension, perforating the thin layer overlying a deep ulcer [15] and (2) bowel ischemia may be attributed to inflammation of the small vessels without dilatation and strictures [16]. Both theories may contribute to perforation as reported in the present case. The patient had ulcer, stenosis, and inflammation of the jejunum but no bowel distension in the intra-operative findings.

The duration of Crohn disease before free perforation was 25 months (range, 0.3–214 months) in the Japanese study. Seventy-two (72) patients (57.1%) were confirmed as having Crohn disease for the first time at laparotomy for free perforation [11]. The median time interval between the first symptom of free perforation and a diagnosis of Crohn disease was 5.1 (0–276.6) months in the Korean study [10]. The present case had first symptom (abdominal pain and diarrhea) one month prior. The present case is a rare occurrence of a complication of Crohn disease before diagnosis of the disease. The present case reports spontaneous solitary free perforation of the small bowel (jejunum) in Crohn disease.