# Transmesocolic Hernia of the Ascending Colon: A Rare Cause of Small Bowel Obstruction in an Older Patient

## TL;DR

A rare case of transmesocolic hernia causing small bowel obstruction in an elderly woman is reported, highlighting the importance of early diagnosis and surgery.

## Contribution

This case report adds to the limited literature on transmesocolic hernias of the ascending colon as a cause of small bowel obstruction.

## Key findings

- A 95-year-old woman presented with symptoms of small bowel obstruction due to a transmesocolic hernia.
- Emergency surgery confirmed a congenital mesocolon defect with strangulated jejunal herniation.
- The patient recovered well post-surgery with no complications.

## Abstract

Transmesocolic hernia of the ascending colon is an extremely rare cause of small bowel obstruction. Due to its rarity and nonspecific clinical features, preoperative diagnosis of internal hernia is challenging.

We report the case of a 95-year-old female patient (body mass index: 19.5) without a history of abdominal surgery, who presented with vomiting and abdominal pain. The patient had a medical history of cerebral infarction, pneumonectomy, hypertension, hyperlipidemia, and dementia. Laboratory test results revealed leukocytosis and mild inflammation. Abdominal CT revealed closed-loop ileus on the left side of the ascending colon with localized small bowel dilatation. Chest CT indicated aspiration pneumonia. Based on these findings, a preoperative diagnosis of an internal hernia with strangulated ileus and aspiration pneumonia was made, necessitating an emergency surgery. Intraoperatively, a segment of the jejunum located 50–70 cm from the ligament of Treitz was herniated through a congenital defect in the ascending mesocolon. The ischemic jejunal bowel was resected and the mesenteric defect was closed. The operative time was 81 min with minimal blood loss. The patient experienced no surgical complications and was discharged on postoperative day 50, following treatment for aspiration pneumonia.

Although transmesocolic hernias of the ascending colon are extremely rare, they should be considered in the differential diagnosis of small bowel obstruction, particularly in older, thin female patients without a history of abdominal surgery. Early diagnosis and timely surgical intervention are essential for achieving favorable outcomes.