Case Report

Colonic subepithelial lesions encompass a broad spectrum of entities with varying clinical significance, often identified incidentally during endoscopy. Their endoscopic appearance is frequently nonspecific, making differential diagnosis essential. Common considerations include lipomas, gastrointestinal stromal tumors, leiomyomas, and neuroendocrine tumors.1-2

We present the case of an asymptomatic 57-year-old woman with an unremarkable medical history who underwent
colonoscopy for colorectal cancer screening.
Colonoscopy revealed a polylobulated subepithelial lesion measuring approximately 40 mm in the sigmoid colon, located 40 cm from the anal verge, along with additional smaller erythematous lesions with similar features (Fig. 1 and 2).

Figure 1

Figure 2

For further characterization, endoscopic ultrasound was performed using a 12-MHz miniprobe, which demonstrated multiple structures with a hyperechoic wall and an anechoic to hypoechoic center, along with air reverberation artifacts, consistent with gas within the submucosal layer (Fig. 3, 4 and 5).

Figure 3

Figure 4

Figure 5

Based on these endoscopic ultrasound findings, what do you think is the most likely diagnosis?

Submeter

As the patient remained asymptomatic, no treatment was initiated.

Discussion

Pneumatosis cystoides intestinalis (PCI) is a rare condition defined by the presence of gas-filled cysts within the bowel wall, typically located in the submucosa or subserosa. 3 The frequency of PCI increases after the fifth decade of life, with a similar incidence in men and women.4 The estimated worldwide incidence ranges from 0.3% to 1.2%. 3 PCI most commonly affects the jejunum and ileum, with only about 6% of cases involving the colon (pneumatosis coli), where cysts are more often found in the submucosal layer. 5-6

PCI is classified into primary/idiopathic and secondary forms, accounting for approximately 15% and 85% of cases, respectively. 4,8 The primary form is usually benign and often asymptomatic. Secondary form is associated with various conditions, including ischemic bowel disease, Hirschsprung disease, infections, diabetes mellitus, and chronic obstructive pulmonary disease. 7
The exact etiology of PCI remains unclear, but several hypotheses have been proposed, including mechanical, bacterial, and biochemical mechanisms. 4-6
Clinical presentations are variable. Many patients are asymptomatic, especially in primary PCI. 5, 6 When symptoms occur, they may include abdominal pain, abdominal distension, diarrhea or constipation, and hematochezia. 4,5 Nonspecific symptoms such as nausea, vomiting, or weight loss may also be present, particularly in secondary forms. 4,5
Complications of Pneumatosis intestinalis, although uncommon, can be serious and include bowel obstruction, intussusception, volvulus, and intestinal perforation. 4,5,7
Diagnosis is generally based on imaging studies such as plain abdominal radiography or computed tomography, as well as endoscopy. 5,8 Endoscopic ultrasound may provide additional value by helping to characterize the cysts without exposure to radiation. 3
Management depends on the presence and severity of symptoms. In asymptomatic patients, treatment is usually not required, as spontaneous resolution may occur in up to 50% of cases. 4,5,7 Symptomatic patients may be managed conservatively with antibiotics, an elemental diet, and oxygen therapy, including hyperbaric oxygen in selected cases. 4,8

References

1-Minoda Y, Ihara E, Nakamura K, Fuchigami T. Current diagnosis and management of gastrointestinal subepithelial tumors. World J Gastroenterol. 2023;29(2):188–204.
2- Deprez PH, Moons LMG, OʼToole D, Gincul R, Seicean A, Pimentel-Nunes P, Fernández-Esparrach G, Polkowski M, Vieth M, Borbath I, Moreels TG, Nieveen van Dijkum E, Blay JY, van Hooft JE. Endoscopic management of subepithelial lesions including neuroendocrine neoplasms: European Society of Gastrointestinal Endoscopy (ESGE) Guideline. Endoscopy. 2022 Apr;54(4):412-429.
3- Yvamoto EY, Cheng S, de Oliveira GHP, Sasso JGRJ, Boghossian MB, Minata MK, Ribeiro IB, de Moura EGH. Endoscopic Ultrasound View of Pneumatosis Cystoides Intestinalis. Diagnostics (Basel). 2023 Apr 15;13(8):1424.
4- Catena F, Ansaloni L, Di Saverio S, et al. The challenge of pneumatosis intestinalis: a contemporary systematic review. J Pers Med. 2024;14(2):167.
5- Ho LM, Paulson EK, Thompson WM. Pneumatosis intestinalis in the adult: benign to life-threatening causes. AJR Am J Roentgenol. 2007;188(6):1604–1613.
6- Koss LG. Abdominal gas cysts (pneumatosis cystoides intestinalis): an analysis with a review of the literature. Arch Pathol. 1952;53(6):523–549.
7- Wu LL, Yang YS, Dou Y, Liu QS. A systematic analysis of pneumatosis cystoids intestinalis. World J Gastroenterol. 2013 Aug 14;19(30):4973-8.
8- Truong K, Wahood W, Luna C, Dosch A, Blain Y. Pneumatosis intestinalis revisited: associated imaging findings, clinical correlation, and management. Emerg Radiol. 2026

 

Authors

Ana Rita Silva, Nadine Amaral, Catarina Cardoso, Francisca Côrte-Real, Diogo Bernardo Moura, Carolina Chálim Rebelo, Margarida Flor de Lima, Filipe Taveira, Maria Pia Costa Santos, Ana Catarina Rego, José Renato Pereira, Nuno Paz

Hospital do Divino Espírito Santo de Ponta Delgada