Case Report: Acute peritonitis inaugurating Crohn's disease with spontaneous perforation in the peritoneal cavity

Introduction

Crohn’s disease (CD) is a chronic transmural inflammation that can affect the gastrointestinal tract from the mouth to the anal margin.¹ Inaugural spontaneous perforation with generalized peritonitis is infrequent and potentially life-threatening occurrence.² Herein, we present a case study of acute generalized peritonitis caused by the perforation of a distal ileal loop, leading to the diagnosis of Crohn's disease.

Case presentation

A 43-year old man presented to the emergency department with a one-day history of abdominal pain and vomiting. There were no signs of bowel obstruction or fever. The patient had no medical or surgical history, and was a non-smoker. He reports paroxysmal abdominal pain and diarrhea for the last year.

On examination, his temperature was 37.4 °C and generalized abdominal tenderness were noticed. The maximum pain was at the level of the right iliac fossa. Hemodynamic state remained stable, and the respiratory rate was normal.

Laboratory data showed elevated white blood cell count (18500/mm³) and C-reactive protein level (140 mg/l). The results of the serum electrolyte and kidney function tests were normal.

Acute appendicitis complicated with peritonitis were considered and the patient underwent urgent laparoscopic exploration, without morphologic exploration.

The peroperative exploration of the abdominal cavity found a free purulent fluid caused by a perforation in the anti-mesenteric border at the distal ileum (Figure 1), 40 cm from the ileocecal valve. Furthermore, we observed the presence of an inflammatory-looking conglomerate of small bowel loops associated with sclerolipomatosis (Figure 2 and 3). Terminal ileal loop, caecum and appendix were grossly normal. Due to poor exposure conditions, we decided to convert to a midline procedure.

Figure 1. Intraoperative view showing the perforation of the anti-mesenteric border of the bowel (white arrows).

a: Specimen after resection, (the yellow asterisk shows the sclerolipomatosis), b: Appearance of the perforation before resection.

Figure 2. Intraoperative view showing the conglomerate of small bowel loops associated with sclerolipomatosis (yellow asterisk).

Figure 3. Intraoperative view showing the appearance of intense sclerolipomatosis (yellow asterisk).

An abundant peritoneal toilet with serum salin and ileocaecal resection carrying out 50 cm of bowel were performed. Remaining bowel length was estimated at 4.5 meter. An ileo-colostomy in the right iliac fossa was performed.

The post-operative course was uneventful. First oral intake was allowed since the first post-operative day. The patient was discharged on the fifth postoperative day.

The histopathological analysis of the specimen revealed a chronic granulomatous ileitis lesions, which are indicative of Crohn's disease.

Discussion

Crohn's disease is a chronic inflammatory disease of unknown origin that has the potential to impact the entire gastrointestinal tract from the mouth to the anus.² Although, the terminal ileum and colon are the most frequently involved areas.³ The transmural characteristic of Crohn's disease (CD) can lead to localized perforation, which has the potential to progress rapidly into generalized peritonitis.¹ Free perforation of the small intestine in the peritoneal cavity is a rare and serious complication in Crohn's disease (CD).⁴

The originality of our case lies in the fact that peritonitis secondary to ileal perforation was inaugural, leading to the diagnosis of Crohn's disease.

The diagnosis of acute peritonitis can be considered on physical examination.⁴ However, the challenge of conducting etiological investigations is particularly pronounced, especially given the absence of supportive findings in the medical history for Crohn's disease.⁵ In our case, paroxysmal abdominal pain and diarrhea suggest Crohn's disease and a CT scan could be performed to better support the diagnosis. However, the surgery was obviously required, regardless of the scan features. For this reason, the patient underwent a laparoscopic exploration without any morphological investigations.

Perforative peritonitis as a primary manifestation of Crohn's disease is very rare, and occurs in 1 to 3 % in general population.^2,4 However, The CONNECT retrospective cohort Korean study reported a higher incidence of 6,5% which is similar to a Japanese meta-analysis result.^2,3,6

Among the reported cases of perforation in various literature, the most frequently site affected is ileum, particularly the terminal ileum (80%).^2,4 Less frequently involved locations consist of other segments of the ileum, the colon, and the jejunum.^2,4

The precise mechanism behind the occurrence of free perforation in Crohn's disease remains unidentified. However, many risk factors may be incriminated such as anti TNF therapy or significant distension upstream of a stenosis.^3,4

Surgical treatment involves performing a limited resection of the affected segment of the bowel, followed by either a primary anastomosis or a temporary stoma.³ In this particular case, considering the peritoneal contamination, an ileocecal resection with a stoma was performed.

Conclusion

Although Crohn’s free perforation in the peritoneal cavity is infrequent, it should be kept in mind especially in front of suggestive features.⁴ Timely diagnosis and prompt treatment significantly enhance the prognosis.⁵ Surgery is obviously required for acute peritonitis, with limited resection with or without anastomosis.

Consent

Written informed consent to publish this case and associated images was obtained from the patient.