Acute colocolic intussusception: A rare pediatric presentation

Abstract

Colocolic intussusception, a rare but significant condition in pediatric patients, involves the invagination of a segment of the colon into an adjacent segment. This phenomenon can result in various complications, such as bowel obstruction and ischemia, highlighting the importance of prompt diagnosis and intervention. Radiology plays a pivotal role in the identification and management of this condition, employing various imaging modalities to visualize the characteristic features of intussusception, ultrasound is the preferred imaging method due to its high specificity and sensitivity. We report the case of a 9-month-old male infant with colocolic intussusception involving the descending colon and sigmoid with no pathological lead point, which led to ischemia and necrosis, necessitating resection of the necrotic segments and anastomosis.

Introduction

Intussusception is a medical condition in children where a segment of the intestine slides into an adjacent part. This telescoping of the intestine can result in swelling, decreased blood flow, and potentially life-threatening complications if left untreated [1]. It most commonly occurs in infants and toddlers, with symptoms such as sudden abdominal pain, vomiting, and “currant jelly” stools. Diagnosis is usually done through ultrasound [2].

Colocolic intussusceptions in children are a rare entity compared to ileocolic intussusceptions, which can lead to distinct diagnostic challenges [3]. Diagnosis is also through imaging, but due to its rarity, it can be harder to detect. Treatment is similar to other forms of intussusception, though surgical intervention may be required more frequently [4].

Case report

We report the case of a 9-month-old infant with no significant medical history presenting to the pediatric emergency department of the Children's Hospital of Rabat with 1-day history of hypotonia and lethargy, associated bloody stools, without any other significant clinical signs. The clinical examination revealed a palpable mass in the left iliac fossa, suggesting an intussusception.

An abdominal ultrasound on the radiology emergency department has shown a colocolic intussusception on the left lower quadrant involving the descending colon and sigmoid, with a typical image of the target sign on a transverse view and the pseudokidney sign on a longitudinal view (Fig. 1). Signs of intestinal distress were also present, marked by hypovascularization of the bowel loops in color Doppler, parietal thickening, and the presence of fluid around the intussusception (Fig. 2). The combination of the clinical presentation and this ultrasound appearance suggests the diagnosis of acute colocolic intussusception, complicated by digestive distress. Immediate surgery was performed, confirming the left colocolic intussusception with digestive necrosis involving the descending colon. The necrotic portion was resected, followed by an anastomosis (Fig. 3).

Fig. 1.

Ultrasonographic appearance of the intussusception, showing a target sign on transverse view (arrows, A) and pseudokidney or sandwich sign on longitudinal view (arrows, B).

Fig. 2.

Ultrasonographic signs of a complicated colocolic intussusception, showing parietal thickening (red arrows, A), parietal hypovascularization of the bowel loop on color Doppler (Yellow arrows, B), and effusion around the colocolic intussusception (White arrow, C).

Fig. 3.

Intraoperative image displaying extensive necrosis of the descending colon (arrows).

No pathological lead point associated with secondary acute intestinal intussusception was found during the surgical exploration. The patient had a favorable outcome, with no signs of postoperative complications.

Discussion

Intussusception is a medical condition that can affect both the small intestine and the colon and can be defined as the telescoping of a segment called the intussusceptum into an adjacent segment called the intussuscipiens. The most prevalent type in children, characterized by a segment of the distal ileum invaginating into the colon, is ileocolic intussusception. It is considered one the most common causes of intestinal obstruction in the pediatric population [1].

The global incidence is variable between different regions and depends on healthcare standards. In Europe, it is 20 per 100,000, while in other parts of the world, the rate is estimated to be just under 100 cases per 100,000 births, though significant disparities exist between countries [1,5]. Male sex accounts for approximately 60% of cases [6]. Patients with idiopathic ileocolic intussusception are typically aged between 6 months and 3 years, with the highest incidence occurring between 5 and 9 months [7].

Colocolic intussusceptions involving only the colon are much less common than ileocolic intussusceptions. Due to their relative rarity, the exact incidence is unclear, but some studies suggest that colocolic intussusceptions account for about 3% of all intussusception cases [3]. They usually occur outside the typical age range of 6 months to 3 years in older patients [8].

In children, up to 90% of intussusception cases are idiopathic, often linked to hypertrophy of lymphoid tissues, such as Peyer's patches or lymph nodes, which are particularly concentrated in the ileocecal region [5]. The remaining 10% of cases are secondary, with their frequency increasing as the child grows older. These secondary cases are typically associated with local factors, such as Meckel's diverticulum, intestinal duplication, polyps, angiomas, or lymphoma. Additionally, certain general conditions like cystic fibrosis, Henoch-Schönlein purpura, and hemophilia, as well as specific contexts such as postoperative recovery or chemotherapy, can also predispose a child to intussusception [1,5].

From a pathophysiological perspective, Intestinal peristalsis pushes the intussusceptum into the intussuscipiens, pulling the mesentery and vessels along, which become constricted. This movement is aided by defects in colonic attachments and is only restricted by the length of the mesenteric root. Compression at the neck results in venous and lymphatic congestion, leading to edema that further increases the pressure, cutting off arterial blood flow and possibly causing damage to the intestinal mucosa, resulting in bloody stools. In more severe cases, it can result in intestinal wall necrosis and perforation if diagnosis is delayed. Nerve compression triggers the typical intense paroxysmal pain of intussusception, though spontaneous reduction may also occur [9,10].

Abdominal pain, bloody stools, and vomiting are typically viewed as the primary symptoms of intussusception. However, only around 25% of patients present with this classic triad, which can result in delayed or incorrect diagnoses [7]. In colocolic intussusceptions, patients tend to present with bloody stools [3]. Other symptoms, such as lethargy and irritability, can also be predictors of intussusception, especially for children under 24 months. [11] Our case presented with neurological symptoms of hypotonia and lethargy, along with bloody stools.

Imaging is crucial for diagnosing intussusception.

Plain radiographs may reveal indirect signs of intussusception, such as air-fluid levels in the case of intestinal obstruction, intestinal distension, and absence of gas in the distal colon.

However, their role in the diagnostic strategy has significantly decreased with the advancement of imaging techniques [5].

Ultrasound is the preferred imaging technique for diagnosing intussusception due to its high specificity and sensitivity, as well as its speed and ease of use [2]. Typical ultrasound findings feature the classic target or donut sign in transverse views, which is marked by concentric rings, and the presence of parallel stripes In longitudinal views with varying echogenicity may suggest the appearance of a pseudokidney or sandwich sign [12,13].

All abdominal areas must be thoroughly examined, as the lead point of the intussusception may extend to the rectum. An ileocolic or colocolic intussusception typically ranges from 3 to 5 cm in diameter and lies just beneath the abdominal wall, making it a relatively “easy” mass to identify on ultrasound compared to ileoileic intussusceptions [1].

It is also crucial to look for signs of digestive distress on ultrasound, particularly hypovascularization of the bowel loops in color Doppler [1], parietal thickening [14], the presence of fluid within the intussusception [15], the presence of air encircling the invaginated segment [16], along the presence of peritoneal effusion. The ultrasound performed in the emergency department for our patient indeed showed these signs of distress, particularly the parietal hypovascularization and thickening, and fluid surrounding the intussusception.

An image-guided enema is not justified as a first-line diagnostic tool in the presence of an experienced radiologist, as ultrasound is a more appropriate tool with no risk of radiation exposure [5,9].

While not commonly used in children due to radiation exposure, a CT scan can be employed in the presence of an atypical clinical presentation, uncertain diagnosis, or a complex case. This modality provides a more detailed view of the bowel and surrounding structures. It can also help to identify the lead point in cases where a mass, polyp, or tumor is causing the intussusception [17].

Intussusception is considered to be a serious condition that requires immediate intervention. Before any therapeutic management, it is essential to relieve the patients and rehydrate them if the symptoms have lasted more than 24 hours or in the presence of signs of dehydration [5]. Regardless of the age at which intussusception occurs, nonsurgical reduction is offered as the first-line treatment, using a minimally invasive approach whenever possible, via pneumatic or hydrostatic enema under sedation or general anesthesia, with fluoroscopic or ultrasound guidance [4,18].

If nonsurgical methods are unsuccessful or if there are indications of complications such as perforation, necrosis, or ongoing obstruction as evidenced by imaging, surgical intervention becomes necessary. The surgeon may either manually reduce the intussusception or, if there is any damaged tissue, perform a resection of the affected segment of the intestine [1,4].

This was the case for our patient, who underwent immediate resection of the necrotic portion of the colon with anastomosis.

Treatment of an underlying local cause is surgical, with caution required in cases of tumors.

Postsurgery, vigilant monitoring, and a gradual reintroduction of nutrition are crucial. Pain management and prevention of complications, such as infections, are also important.

Conclusion

Colocolic intussusception, while less common than ileocolic intussusception, presents unique challenges in diagnosis and management. This condition underscores the importance of recognizing atypical presentations, as the classic triad of symptoms may not always be present. Advances in imaging, particularly ultrasound, facilitate early detection and minimize radiation exposure, allowing for prompt intervention. While nonsurgical reduction remains the first-line treatment, surgical options may be necessary in cases with complications. By focusing on colocolic intussusception and ensuring comprehensive care, healthcare providers can significantly improve outcomes for affected patients.

Ethic approval

All guidelines have been diligently followed, including those set forth by the Committee on Publication Ethics (COPE), and International Committee of Medical Journal Editors (ICMJE) ensuring transparency in authorship, contributorship, and dispute resolution processes.

Guarantor of submission

The corresponding author is the guarantor of submission.

Patient consent

Written informed consent was obtained from the legally authorized representative of the subject (minor patient) for the publication of this case report.