Natural history and surgical treatment of a giant colonic diverticulum: A case report

Abstract

BACKGROUND

While diverticular disease is prevalent in the West, the formation of giant colonic diverticula is rare. To date, approximately 200 cases have been reported, with only a handful treated surgically using a minimally invasive approach. Furthermore, the natural history of giant colonic diverticula is not well documented.

CASE SUMMARY

This report describes the case of a 66-year-old man who developed a giant colonic diverticulum with primary symptoms including dull and chronic pain in the right lower quadrant at presentation. The patient had undergone several computed tomography scans of the abdomen and pelvis over the previous two years, through which the natural history of this rare entity could be retrospectively observed. The patient was successfully treated with a robot-assisted sigmoid colectomy and had an uneventful recovery with resolution of symptoms during the follow-up.

CONCLUSION

This rare case demonstrates the natural history of giant colonic diverticulum formation and supports the feasibility of robot-assisted surgery.

Key Words: Giant colonic diverticulum, Robotic colectomy, Computed tomography, Enhanced recovery, Case report

Core Tip: Giant colonic diverticula are a rare complication of diverticular disease. Although the symptoms may sometimes be indolent, the present case suggests that they may continue to worsen if managed conservatively. In appropriate patients, a minimally invasive approach is feasible and can lead to enhanced postoperative recovery.

INTRODUCTION

Diverticular disease remains prevalent in the West, affecting approximately 50% of patients by the age of 50 years. Common complications of this condition include acute and perforated diverticulitis, large bowel obstruction, and hemorrhage. The formation of giant colonic diverticula is rare with approximately 200 cases having been previously reported in the literature. Typically located in the sigmoid colon, giant colonic diverticula are defined as those greater than 4 cm in diameter. Among the reported cases, most were treated surgically, although only a few of the surgeries employed a minimally invasive approach[1]. This report describes a patient who developed this rare condition and presents the details of his management.

CASE PRESENTATION

Chief complaints

A 66-year-old male presented with chronic right lower quadrant abdominal pain.

History of present illness

The patient’s symptoms were chronic abdominal pain localized to the right lower quadrant and had been present for approximately 2 years. A surgical referral was requested because computed tomography (CT) revealed a giant colonic diverticulum.

History of past illness

The patient had a history of atrial fibrillation, chronic obstructive pulmonary disease, hypertension, and hyperthyroidism. He had also undergone cardiac ablation in addition to laparoscopic cholecystectomy, which had been performed for acute cholecystitis. He experienced an episode of acute diverticulitis two years prior to presentation.

Personal and family history

The patient denied having any family history of diverticular disease.

Physical examination

Upon examination, his abdomen was soft and non-tender with no palpable mass.

Laboratory examinations

His laboratory results including the white blood cell count were within normal limits.

Imaging examinations

The patient had recently undergone CT of the abdomen and pelvis, which revealed a giant sigmoid colonic diverticulum in the right lower quadrant with thickening of the colon wall and measuring 9.7 cm in diameter (Figure 1).

Figure 1 Coronal view of the patient’s most recent computed tomography scan demonstrating a large colonic diverticulum in the right lower quadrant.

Two years before this presentation, the patient had undergone a CT scan during an episode of acute diverticulitis. This scan revealed a diverticulum approximately 3 cm in diameter (Figure 2). One year later, he underwent another CT scan when he developed abdominal distension after cardiac ablation, at which point the diverticulum was approximately 6 cm in diameter. Six months later, the patient presented to the emergency department with right upper quadrant pain and underwent a CT scan, which revealed findings consistent with acute cholecystitis. Incidentally, the diverticulum was also seen, and measured 8 cm in diameter at that time.

Figure 2 Series of computed tomography scans with axial views demonstrating progressive enlargement of the giant colonic diverticulum prior to surgery. A: 2 years prior; B: 1 year prior; C: 6 months prior; D: 1 month prior.

Further diagnostic work-up

Notably, the patient underwent a recent colonoscopy that revealed sigmoid diverticular disease in addition to two small tubular adenomas, although the giant diverticulum could not be visualized.

FINAL DIAGNOSIS

After reviewing the patient’s history and imaging findings, the final diagnosis was giant colonic diverticulum.

TREATMENT

After a discussion, the patient underwent robot-assisted sigmoid colectomy. Prior to the operation, the patient underwent an enhanced recovery after surgery (ERAS) protocol, which included both mechanical and oral antibiotic bowel preparations and administration of intrathecal morphine. The operation was uneventful, and primary anastomosis was performed. During surgery, the patient was found to have a redundant sigmoid colon, with a diverticulum located near the distal sigmoid colon. The diverticulum had a thick wall with vascular adhesions to the right lower anterior abdominal wall (Figure 3).

Figure 3 Intraoperative image of the giant colonic diverticulum.

OUTCOME AND FOLLOW-UP

His postoperative course was uneventful; utilizing an enhanced recovery protocol, the patient showed an early return to bowel function and was discharged on postoperative day 2. During postoperative visits, the patient experienced resolution of chronic right lower quadrant pain and showed improvement in his bowel habits.

DISCUSSION

Pathogenesis

Giant colonic diverticulum is a rare complication of diverticular disease, with only a few cases reported in the literature. McNutt et al[2] classified this into three types, with most patients (type 2) developing the condition because of subserosal perforation. It is theorized that this gradually increases in size owing to a ball-valve mechanism, in which air and stool can enter the diverticulum but not exit. Some patients also present with a colonic pseudodiverticulum with remnants of the muscularis mucosa and muscularis (type 1). The rarer type is a true diverticulum that typically has a congenital origin and is found during childhood (type 3). The patient in this case report was most likely to have a type 2 giant colonic diverticulum. Furthermore, the ball-valve mechanism explains the progressive increase in diverticulum size.

Presentation

Although occasionally detected incidentally, the most common symptoms include abdominal pain, constipation, bloating, and diarrhea. In some patients, abdominal masses were palpable. Typically, a diagnosis is made using CT; however, in certain instances, it may be diagnosed via barium enema or even plain radiography.

Giant colonic diverticula may also result in complicated diseases that require urgent intervention. While several cases of perforated giant colonic diverticula have been reported[3], there have also been reports of obstruction[4] and colonic volvulus[5].

Surgical management

Originally, diverticulectomy was considered an option for treating patients with giant colonic diverticula. In a case series involving four patients, Choong and Frizelle[6] described resecting the diverticulum at the base and oversewing the resultant colonic defect. However, as giant colonic diverticula is now considered a complication of diverticular disease, and sigmoid diverticulosis is typically present, segmental colectomy has become the preferred approach.

In a 2015 case series of 166 patients with giant colonic diverticula, most patients were treated with segmental colon resection and primary anastomosis[1]. Other treatment options included Hartmann’s procedure. Only five patients were treated laparoscopically. In 2019, the first reported robotic colectomy was performed for the treatment of a giant colonic diverticulum[7]. This is the third known case in which a robotic approach was utilized. Both robotic and laparoscopic minimally invasive surgery (MIS) have been shown to have numerous benefits for patients undergoing colectomy, including decreased morbidity, postoperative pain, and a shorter length of stay[8]. Similar to the present case, Veneroni et al[9] discussed the benefits of using an ERAS protocol when treating patients with giant colonic diverticula.

CONCLUSION

This case reinforces the feasibility of a robotic approach for the treatment of giant colonic diverticula. Given its myriad benefits, MIS should be considered whenever possible for treating this condition. Furthermore, by demonstrating the enlargement of a giant colonic diverticulum over a two-year period, this report may help elucidate the clinical course of patients with giant colonic diverticula who may be at a high risk of undergoing surgery.