An Unusual Case of Small Bowel Volvulus Associated with Pneumatosis Intestinalis: A Case Report

INTRODUCTION: Pneumatosis cystoid intestinalis (PCI) is a rare disease reported in the literature affecting 0.03% of the population. It has a variety of causes and its manifestation may change widely. In the acute complicated form of pneumatosis intestinalis, management is challenging for physicians and surgeons. CASE PRESENTATION: We present a case of a 60-year-old patient who was admitted to our surgical department with a symptomatology suggestive of small bowel occlusion. Computed tomography demonstrated ileal volvulus associated with parietal signs suffering and pneumoperitoneum. An emergent exploratory laparoscopy followed by conversion was performed demonstrating segmental ileal pneumatosis intestinalis secondary to a small bowel volvulus due to an inammatory appendix wrapping around the distal ileum. Detorsion, retrograde draining, and appendectomy were performed. DISCUSSION: PCI is an uncommon disease, affecting 0.03% of the population. It is usually presenting as a marginal nding resulting from various gastrointestinal pathologies. This case is exceedingly rare in the literature, featured by the ileal volvulus due to appendicitis. CONCLUSION: This work emphasizes the importance of surgical procedures in the management of symptomatic pneumatosis intestinalis.

DISCUSSION: PCI is an uncommon disease, affecting 0.03% of the population. It is usually presenting as a marginal nding resulting from various gastrointestinal pathologies. This case is exceedingly rare in the literature, featured by the ileal volvulus due to appendicitis.
CONCLUSION: This work emphasizes the importance of surgical procedures in the management of symptomatic pneumatosis intestinalis.

Introduction:
Pneumatosis cystoid intestinalis (PCI) is a low-incidence pathology de ned by the existence of air in the small intestine or colon's wall (1). PCI can affect any portion of the gastrointestinal tract and could be present in any layer such as the mucosa, submucosa, or subserosa (1)(2)(3). It can either be presented as a secondary form in 85% of cases or an idiopathic form in 15% of cases (1,2). the secondary pattern occurs more frequently in gastrointestinal causes such as bowel obstruction (3,4). the management of PCI is challenging to surgeons especially in symptomatic cases (5). We report a rare case of ileal pneumatosis cystoides associated with small bowel volvulus, presenting with acute abdominal pain.
Case Report: A 60-year-old male patient without any medical or surgical history consulted the emergency department for 24 hours of abdominal pain, distension and vomiting. The patient had presented this pain a year earlier which faded away spontaneously. On physical examination, tachycardia and distended abdomen with mild tenderness were noted. White blood count was 8840 E/mm3 and C reactive protein was 36 mg/l. X-ray of thorax and abdomen showed dilated small bowel, multiple uid levels and pneumoperitoneum ( Figure A).
An abdominal CT scan was performed, revealing distended small bowel loops upstreaming transitional levels like a 'whirl sign' (Figure B1), a bubbly pattern across the length of the small bowel associated with parietal suffering signs ( Figure B2), abundant pneumoperitoneum ( Figure B3), and a pathological meso-celiac appendix ( Figure B4). The CT scan has suggested a diagnosis of ileal volvulus due to the meso-celiac appendix.
We initially decided to perform laparoscopy. Intraoperatively, small bowel loops were much dilated not allowing intraperitoneal exploration. Gas-lled cystic lesions on small bowel serosa were identi ed. There was no evidence of perforation. We did choose to convert for better and prudent exploration. A volvulus was found, involving a two-and-ahalf clockwise turn around a long, pendulous small bowel mesentery, the strangled bowel was greatly congested ( Figure C1). At the base of the volvulus, an in ammatory appendix was wrapped around the last loop of the ileum ( Figure C2). Also, multiple gas-lled subserosal cysts, differently sized, on the wall of the ileum were encountered ( Figure C3). When the ileum was re-rotated, Small bowel loops had preserved vitality. The entire colon was normal.
Postoperatively, the patient completed a ve-day course of intravenous metronidazole. There were no postoperative complications. Anatomopathological examination revealed an in ammatory appendix without malignancy. A lower endoscopy was completed after surgery. It showed the presence of two polyps on the rectum and the transverse colon in low-grade dysplasia with no other lesions.

Discussion:
PCI is an uncommon disease (0.03% of adults) (6). Its pathogenesis is still not clear (7). According to its etiology, literature classi es this entity as a primary or secondary type (8). The idiopathic type usually affected the left colon and is rarely reported in the literature. We found thirteen cases of primary PCI described in the international literature.
We summarized the cases in Table 1. However, the secondary type affected frequently the small intestine and the right colon (9). Its pathogenesis is multifactorial, can be explained by 3 theories: mucosal disruption, bacterial theory, and pulmonary disease (1,7,10,11). The mucosal disruption is due to the dissemination of bowel gas through a mucosal defect into lymphatic channels (1, 10). Wu et al. (12) found that high altitude is a new theory explaining PCI's pathogenesis: Highland areas induce passage of intraluminal gas into the submucosa damaging the mucosa.
Mucosal damage can result from bowel occlusion, in ammatory process, and cytotoxic medical treatment (11). The pulmonary cause is con rmed in patients with asthma and chronic bronchitis: in these cases, the rupture of alveoli causes the migration of air bubbles from interstitial spaces through the mediastinum and from the retroperitoneum to the blood vessel of the intestinal wall (1,8,10). However, the bacterial theory is explained by bacterial gas entry due to a defect on the bowel wall lymphoid tissue (8, 10). This mechanism can justify the use of antibiotics (1).
Chemotherapy or hormonal therapy, and systemic sclerosis were reported in the literature as a cause of PCI (1).
Finally, while keeping in mind these theories, their pathogenesis has not been yet fully clari ed (1).
Besides, the disease's location on the digestif tractus may be helpful to guide the etiology. So pyloric stenosis or gastric cancer can lead to a proximal pathology; however distant one might be due to mesenteric ischemia or diverticulitis (9).
PCI is a rare entity reported in the literature, but nowadays PCI reports' number has been increasing because of the widespread use of CT scan and colonoscopy (9). This pathology is more frequently asymptomatic (1). Whereas in some cases, they may present with symptoms such as abdominal pain, constipation, distension, diarrhea, or bleeding (8, 9). Incidentally PCI can induce surgical complications such as bowel obstruction, intestinal perforation, volvulus, intussusception, and bleeding, which require surgical intervention (13).
Intestinal obstruction can be a rare complication of PCI. This event depends on the size and number of the cysts which lead in certain cases to a reduction of the intestinal lumen, volvulus, perforation, and hemorrhage (7,11). In the literature, PCI associated with volvulus is much more uncommon. Besides this association, one of the highlights of our case is the long and hypermobile small bowel mesentery. Moreover, PCI is discussed to be a mechanical factor leading to irreversible volvulus, also it is disputed that volvulus contributes to ischemia which is an etiological factor leading to PCI (3,14).
Imaging ndings may be helpful to con rm PCI's diagnosis, especially on CT scans (1, 6). Computed tomography can show a grape cluster aspect within the wall of the intestine (1). Three patterns of pneumatosis have been reported in the literature using CT scan imaging: bubble cystoid, a linear pattern, and a circular pattern (1).
Pneumoperitoneum can be explained by the rupture of the cyst on the wall intestine, without any evidence of peritoneal irritation or digestive perforation, like in our case. So that we should be wise to correlate clinical and radiographic ndings, when free air is present below the diaphragm in chest X-ray (8, 9). Pneumatosis intestinalis and portomesenteric venous gas (PVG) are generally debated independently in the literature. This association of radiological ndings usually concludes to the presence of mesenteric infarction, but they may indicate occasionally nonischemic conditions. So that their presence should not be always regarded as signs of severity (13,15,16).
Moreover, according to literature, the rare ndings of PCI and PVG can be present in asymptomatic patients without ominous signs, as described in the series of Sooby et al. (17), including 88 patients with PCI/PVG of which 19 with benign PCI, and of these 19, 6 patients had both PCI and PVG. These patients were put under surveillance, and they had no uneventful recovery.
The management of PCI is not well established, there are no standard therapeutic rules (10). However, the mandatory in its management is to judge whenever it is benign or life-threatening (11). So that it is established that if a CT scan shows intestinal infarction, urgent surgery is mandated. If no signs of intestinal damage is found, a conservative treatment is regarded to be ideal (13). The common conservative procedure is to use metronidazole Antibiotics, which affects intestinal bacteria by the suppression of hydrogen production, and hyperbaric oxygen therapy (2, 6, 8, 10). Nevertheless, a surgical procedure is indicated in complications such as peritoneal irritation or intestinal obstruction (2, 10).
The second particularity in our case is that the volvulus of the small bowel is due to acute appendicitis. This entity is explained by the wrapping of the appendix, due to its particular length, around the ileum occurring volvulus and strangulation (18,19). According to the literature, this mechanism resulted from adhesion of the in amed appendix to the posterior peritoneum forming a turn of the spire of the ileum last loop resulting in volvulus (18,19). In summary, our case is exceedingly rare in the literature, featured by the ileal volvulus due to appendicitis. PCI is a rare disease whose diagnosis is offering a challenge for surgeons. This rare condition can often be associated with benign diseases or it can be proof of intestinal necrosis. Although surgery is mandatory in the complicated pattern, the treatment of asymptomatic forms is more likely conservative. Besides, both surgical and medical approaches can e ciently compete with these challenging diagnoses.

Con ict of interest for all authors:
The authors declare no competing interest.
Compliance with Ethical Standards: The patient has provided both verbal and written consent for the publication of this article. It was made sure that his identity will be kept a secret at all levels.

Consent:
Written informed consent was taken from the patient regarding the publication of this case report. It was made sure that his identity will be kept a secret at all levels. A copy of a written request is available for review if requested.