Surgery for non-Meckel’s small-bowel diverticular perforation: two case reports and a literature review

Abstract

Background

Similar to colonic diverticula, small-intestinal diverticula are often asymptomatic, but may cause life-threatening acute complications. Non-Meckel’s small-bowel diverticular perforation is rare, and the rate of mortality is high. However, there is currently no consensus regarding its therapeutic management.

Case presentation

Case 1: A 73-year-old Japanese man with localized lower abdominal pain was referred to our hospital. Enhanced computed tomography (CT) revealed diverticulitis of the small intestine, which was managed conservatively. Four days after admission, abdominal pain worsened, and repeat CT revealed extraintestinal gas. Emergency surgery was performed for the segmental resection of the perforated jejunum with anastomosis. Case 2: A 73-year-old Japanese woman was transferred to our hospital with small-bowel perforation. CT revealed scattered diverticula in the small intestine and extraintestinal gas around the small-intestinal diverticula. Emergency surgery was performed for the segmental resection of the perforated jejunum with anastomosis.

Conclusions

Conservative treatment for small-bowel diverticular perforation may be attempted in mild cases; however, surgical intervention should not be delayed. Segmental resection of the affected intestinal tract with an anastomosis is the standard treatment. Residual diverticula should be documented because of the possibility of diverticulosis recurrence.

Background

A diverticulum can be located at any location in the gastrointestinal tract, from the upper esophagus to the colon. Non-Meckel small-bowel diverticula are rare, with an incidence of less than 1% in the general population [1]. Although most patients with small-bowel diverticula are asymptomatic, some present with chronic symptoms, such as diarrhea, malabsorption, chronic abdominal pain, and discomfort. It may also cause fatal acute complications, such as intestinal hemorrhage, bowel obstruction, and perforation [2, 3].

Non-Meckel’s small-bowel diverticular perforation is uncommon, and there is no consensus on its therapeutic management. Here, we report two cases of emergency surgery for multiple non-Meckel small-bowel diverticular perforations and discuss their management.

Case presentation

Case 1

A 73-year-old Japanese man was referred to our hospital with localized lower abdominal pain associated with vomiting after the consumption of raw fish. His medical history revealed that he had undergone a sigmoidectomy for sigmoid colon cancer. The patient had no history of allergies and was not on any medication. Physical examination revealed abdominal tenderness and localized guarding of the right upper quadrant. The vital signs were stable except for a fever of 38 °C. Laboratory tests revealed a raised white blood cell count of 10,200/μL and C-reactive protein level of 0.60 mg/dL.

Enhanced computed tomography (CT) revealed a thickened partial small-bowel wall, stranding of peri-intestinal fat, and no obvious extraintestinal gas. Scattered diverticula were observed in the small intestine (Fig. 1A).

Fig. 1

Selected computed tomography (CT) images show the clinical course of perforated small-bowel diverticulum. A Enhanced CT scan at the time of initial presentation showing an inflammatory change in the mesentery adjacent to the thickened small bowel (white arrow). A scattered diverticulum in the small intestine is also noted (arrowheads). B Repeat enhanced CT scans 4 days later showing worsening mesenteric inflammatory changes and the appearance of extraintestinal air (white arrow). These findings were suggestive of perforated diverticulitis

The patient was admitted and managed conservatively with a diagnosis of small-bowel diverticulitis. Four days after admission, the patient complained of abdominal pain and blood tests revealed a markedly elevated inflammatory response. Repeat CT revealed extraintestinal gas around the small-intestinal diverticula (Fig. 1B). Emergency surgery was performed for the segmental resection of the perforated jejunum, followed by functional end-to-end anastomosis. The final pathological analysis revealed perforation of the pseudodiverticulum, phlegmonous peritonitis, and an abscess with numerous bacterial aggregations (Fig. 2). The patient recovered well after surgery with antibiotic therapy and was discharged on postoperative day 11.

Fig. 2

Case 1 A: Surgical specimen shows diverticula in jejunum (white arrows), one of which was perforated (arrowhead). B: Hematoxylin and eosin staining showing perforation of the pseudodiverticulum, phlegmonous peritonitis, and abscesses with many bacterial aggregations. Case 2 A: Intraoperative image of dilated loops of jejunum with multiple small-bowel diverticula (white arrows). B: Surgical specimen showing a diverticulum in the jejunum (white arrows), one of which is perforated (arrowhead)

Case 2

A 73-year-old Japanese woman was transferred to our hospital with small-bowel perforation. She developed abdominal pain after ingesting raw fish and was observed fasting for 2 days, her symptoms did not improve, and she visited a nearby hospital. Her medical history revealed that she had undergone appendectomy for appendicitis and had untreated diabetes. The patient was on medication for psychosomatic illnesses and had no history of allergies. Physical examination revealed widespread abdominal tenderness and guarding, primarily in the left abdomen. The vital signs were stable except for a fever of 37.9 °C. Laboratory tests revealed a raised white blood cell count of 9000/μL and a high C-reactive protein level of 22.7 mg/dL and a high HbA1c level of 9.6%.

CT revealed scattered diverticula from the small intestine to the colon, a thickened partial small-bowel wall, and extraintestinal gas around the small intestine diverticula (Fig. 3). Emergency surgery was performed for the segmental resection of the perforated jejunum, followed by functional end-to-end anastomosis. Intraoperative findings and surgical specimens showed diverticula in the jejunum, one of which was perforated. The final pathological analysis revealed a perforation of the pseudodiverticulum and secondary serositis (Fig. 2). The patient recovered well after surgery with antibiotic therapy and was discharged on postoperative day 7. Later, a small-bowel series revealed numerous small-bowel diverticula (Fig. 4).

Fig. 3

Selected CT images showing multiple diverticula in the small intestine (arrowheads), mesentery inflammatory changes, and extraintestinal air (white arrow)

Fig. 4

Small-bowel series performed at 2 months postoperatively showing multiple and dilated jejunal diverticula (arrowhead)

Discussion

Non-Meckel small-bowel diverticula are rare, and the frequency of autopsy cases was reported by Edwards as 9 out of 2820 cases (0.31%). According to Edward’s locus minoris resistentiae theory, increased intestinal pressure causes a hernia-like prolapse of the mucosa and submucosal tissue out of the intestinal wall at the mesenteric vascular penetration zone, where the muscular layer is underdeveloped, often resulting in multiple pseudodiverticula in the mesenteric attachment zone [1]. Perforation occurs mainly in the mesenteric leaves of the small intestine, resulting in a mesenteric abscess. In our case, diverticula and perforations were also observed on the mesenteric border. We summarized the differences between Meckel’s diverticulum and non-Meckel's small-bowel diverticulum (Table 1).

Table 1 Comparison of Meckel’s diverticulum and nonMeckel’s small-bowel diverticulum

As with colonic diverticula, small-intestinal diverticula are often asymptomatic, but they may cause life-threatening acute complications, such as bleeding, volvulus, obstruction, diverticulitis, and perforation, which can lead to major diagnostic and therapeutic problems [4]. In particular, the mortality rate of diverticular perforation is high, ranging from 21 to 40%, and is closely related to delays in diagnosis and older age [5, 6].

Owing to their rare incidence, there is no clear treatment strategy for small-bowel diverticular perforations. Because of the difference in the pathogenic bacteria, we assume that the same treatment protocols as for upper gastrointestinal perforation cannot be applied. Therefore, we collected cases of small-intestinal diverticular perforation since 2000–2023 and summarized recent trends in treatment strategies (Table 2) [7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32].

Table 2 Summary of previous reports and our cases since 2000 to 2023

The clinical findings vary widely and patients visit the hospital with various concerns. Abdominal pain varied according to its location, severity, and progression. CT plays a major role in the diagnosis of diverticulitis in the small intestine. Localized and asymmetric thickening of the small-intestinal wall and inflammation or abscess of the periportal adipose tissue are the diagnostic criteria for small-intestinal diverticulitis, and when added to these findings of extraintestinal gas, a diagnosis of perforation or permeation can be made [33]. Non-Meckel’s small-bowel diverticula are often multiple, and the presence of diverticula in the normal small intestine may also help in the diagnosis of small-intestinal diverticulitis. In Table 2, however, there are scattered cases in which an exploratory laparotomy is selected even when CT is taken. One reason may be that small-bowel diverticular perforation is a rare disease not mentioned in the differential. The non-surgical management of perforated small-intestinal diverticula is a relatively new concept. When perforation of a small-intestinal diverticulum causes localized peritonitis and the patient remains stable, non-surgical management, such as antibiotics, bowel repose, and CT-guided aspiration of localized intraperitoneal collections, may avoid the need for surgery [18, 21, 23, 24, 31, 34]. On the other hand, emergency surgery is performed when there is remote air from the inflamed diverticulum. Patients successfully treated conservatively are often discharged from the hospital relatively early (2–6 days) [18, 21, 23, 24, 31]. Considering the high mortality rate associated with diverticular perforations of the small intestine, conservative treatment should be provided in limited cases. Even when conservative treatment is selected, surgery should be considered immediately in patients who do not improve after a few days of conservative treatment. In the early stages of the perforation, as in Case 1, it is impossible to determine whether the inflammation stays in the mesentery or spreads. A repeat CT scan may confirm the spread of extraintestinal gas and worsening of inflammatory findings.

We have summarized the main surgical techniques for non-Meckel’s small-bowel diverticular perforation (Table 3). Segmental intestinal resection with primary anastomosis is the most common procedure for perforating diverticula in the small intestine. Other surgical techniques, such as simple closure, invagination, and excision of the perforated diverticulum, should be abandoned because of their high mortality rate [35]. When the diverticula extend over the long intestinal tract, resection should be limited to the perforated or inflamed portion to avoid short-bowel syndrome. The presence of a retained diverticulum should be recorded for future reference in light of case reports of recurrent small-intestinal diverticular perforation after surgery [31, 36].

Table 3 Major surgical techniques for diverticular perforation of small intestine and number of cases in review

Conclusions

Perforation of non-Meckel small-bowel diverticula is rare, but the mortality rate is high and should be considered in the differential diagnosis of acute abdominal pain. Although conservative treatment has been reported, surgery should be performed promptly when symptoms worsen. Segmental resection and anastomosis of the affected intestinal tract are the standard treatments. Residual diverticula should be documented because of the possibility of diverticulosis recurrence.