A Case Series and Brief Review of Literature on Encapsulating Peritoneal Sclerosis: Unveiling the Cocoon

Abstract

This case series explores four distinct instances of encapsulating peritoneal sclerosis (EPS), a rare but serious condition characterized by the encapsulation of abdominal viscera, commonly referred to as abdominal cocoon. EPS is associated with severe complications, including bowel obstruction and sepsis, which can significantly impact patient outcomes. The first case involves a 41-year-old male patient who had undergone a liver transplant and ultimately succumbed to extensively drug-resistant (XDR) sepsis. The second case features a 31-year-old male patient diagnosed with abdominal tuberculosis, who successfully recovered following comprehensive antitubercular therapy (ATT). The third case presents a 26-day-old neonate with CHARGE syndrome (coloboma of the eye, heart defects, atresia of the choanae, retardation of growth and development, genital abnormalities, and ear anomalies, including deafness), who tragically succumbed to septic shock. The last case is of a 41-year-old male patient with disseminated tuberculosis who showed marked improvement with appropriate treatment. These cases illustrate the diverse clinical backgrounds and grave outcomes associated with EPS, highlighting the urgent need for early diagnosis and intervention. Despite EPS being a leading cause of small bowel obstruction in many inpatient settings, its diagnosis is frequently overlooked due to insufficient awareness among healthcare professionals. This series aims to enhance understanding of the causes, imaging characteristics, and management strategies for EPS. By disseminating this knowledge, we hope to facilitate earlier identification of the condition, particularly through primary imaging techniques such as ultrasound (USG). Ultimately, increasing awareness and understanding of EPS is crucial to improving patient outcomes and reducing the associated morbidity and mortality.

Keywords: abdominal cocoon; encapsulating peritoneal sclerosis; encapsulating sclerosing peritonitis; idiopathic sclerosing peritonitis; ldlt complications; peritoneal fibrosis; peritoneal sclerosis; sclerosing encapsulating peritonitis (sep); small bowel occlusion; trilaminar appearance.

Figure 1. a: Contrast-enhanced CT (coronal) showing encapsulated fluid collections in the greater and lesser sacs, with perisplenic collections due to prior infarction. b: CECT (sagittal) showing encapsulated fluid collection. c: Axial CECT depicting encapsulation around small bowel loops clumped and conglomerated toward the root of the mesentery, with dilatation suggestive of subacute intestinal obstruction. d: Fluoroscopic image post-portal vein stenting.

CT: computed tomography, CECT: contrast-enhanced computed tomography, GS: greater sac, LS: lesser sac, EPS: encapsulating peritoneal sclerosis

Figure 2. a and b: Abdominal ultrasound images showing central clumping of small bowel loops toward the root of the mesentery, resembling a cauliflower with a trilaminar appearance: hyperechoic membrane, hypoechoic bowel wall, and hyperechoic lumen.

Figure 3. a: Axial non-contrast CT showing encapsulated ascites forming an "abdominal cocoon" with diffuse, smooth omental nodules suggestive of peritoneal TB. b: Axial contrast-enhanced CT with peritoneal enhancement. c: No evidence of proximal bowel dilatation, obstruction, or peritoneal/bowel wall calcifications.

CT: computed tomography, TB: tuberculosis

Figure 4. a: Axial non-contrast CT showing gross ascites. b: Axial contrast-enhanced CT showing peritoneal enhancement. c: Sagittal contrast-enhanced CT reconstruction showing loculated ascites in the greater and lesser sacs. d: Coronal contrast-enhanced CT showing clumped small bowel loops with peritoneal enhancement. e: Axial contrast-enhanced CT showing peritoneal encapsulation around the clumped small bowel.

CT: computed tomography, GS: greater sac, LS: lesser sac

Figure 5. a: Ultrasound showing stacked small bowel loops with a concertina-like appearance. b: Ultrasound showing central clustering of small bowel loops at the mesentery root, resembling a cauliflower. c: Chest radiograph showing patchy nodular opacities in both lungs. d: Axial HRCT showing peribronchovascular nodules. e: Coronal CT of the chest with enlarged mediastinal and neck nodes.

HRCT: high-resolution computed tomography, CT: computed tomography

Figure 6. a: Axial post-contrast CT section showing hyperattenuating ascites with diffusely thickened, enhancing peritoneal covering, omental caking, and multiple enlarged and necrotic abdominal lymph nodes. b: Axial post-contrast CT section with central clumping of encapsulated small bowel loops without obstruction. c: Ultrasound of the abdomen showing multiple well-defined hypodense lesions in the liver, likely granulomatous infection. d: Coronal contrast CT section showing loculated ascites with enhancing peritoneal covering suggestive of abdominal cocoon (note the hepatic and splenic flexures and descending colon outside the cocoon). Overall imaging features: wet-type abdominal tuberculosis.

CT: computed tomography