Few reports have described living foreign bodies in the human body. The current manuscript demonstrates that computed tomography (CT) is an effective tool for accurate preoperative evaluation of living foreign bodies in clinic. The three-dimensional (3D) reconstruction technology could clearly display anatomical structures, lesions and adjacent organs, improving diagnostic accuracy and guiding the surgical decision-making process.

Herein we describe a 68-year-old man diagnosed with digestive tract perforation and acute peritonitis caused by a foreign body of Monopterus albus. The patient presented to the emergency department with complaints of dull abdominal pain, profuse sweating and a pale complexion during work. A Monopterus albus had entered the patient’s body through the anus two hours ago. During hospitalization, the 3D reconstruction technology revealed a perforation of the middle rectum complicated with acute peritonitis and showed a clear and complete Monopterus albus bone morphology in the abdominal and pelvic cavities, with the Monopterus albus biting the mesentery. Laparoscopic examination detected a large (diameter of about 1.5 cm) perforation in the mid-rectum. It could be seen that a Monopterus albus had completely entered the abdominal cavity and had tightly bitten the mesentery of the small intestine. During the operation, the dead Monopterus albus was taken out.

The current manuscript demonstrates that CT is an effective tool for accurate preoperative evaluation of living foreign bodies in clinic.

Digestive tract perforation is a common acute abdominal pathology[1,2], often secondary to ulcers, trauma, inflammation, tumors, etc. Computed tomography (CT) constitutes an effective tool for accurate preoperative evaluation of foreign bodies in clinic[3]. Preoperative three-dimensional (3D) CT reconstruction accurately locates perforation sites and foreign bodies, helps diagnose peritonitis and guides surgical treatment[4]. In the present case, according to clinical symptoms and signs, combined with plain 3D CT reconstruction, it was determined that the patient had digestive tract perforation, and a Monopterus albus had died after entering the abdominal cavity[5]. As a result, the patient’s abdominal cavity was seriously polluted, with a large amount of turbid yellow fluid and a small amount of feces attached to several intestinal areas, so it could be determined that the patient had “intestinal perforation” caused by a Monopterus albus[6]. The intestinal wall is relatively weak, and may burst out after Monopterus albus bites, which easily causes acute diffuse peritonitis[7]. If not timely treated, patients may develop septic shock, which is a serious and life-threatening condition. Surgical removal of foreign bodies, e.g., Monopterus albus, is the best treatment method, and preoperative imaging evaluation is particularly important[8]. Living foreign bodies are rarely reported in the literature.

Based on the patient’s previous medical history, the patient was eventually diagnosed with digestive tract perforation and acute peritonitis.

Postoperatively, the patient recovered well and was discharged on postoperative 5 d.

The patient recovered without complications.

Few reports have described living foreign bodies in the human body[9]. CT constitutes an effective tool for accurate preoperative evaluation of living foreign bodies in clinic[3]. 3D CT reconstruction clearly displays anatomical structures, lesions and adjacent organs, improving diagnostic accuracy[6]. In the present case, preoperative 3D CT reconstruction accurately located a Monopterus albus outside the intestinal cavity with a perforation site, and the foreign body had damaged the mesentery in the small intestine, causing fluid and gas accumulation, as well as peritoneal thickening[5]. These findings suggest preoperative 3D CT reconstruction may accurately locate perforation sites and foreign bodies, help diagnose peritonitis and guide surgical treatment[4].

Preoperative 3D CT reconstruction can accurately locate perforation sites and living foreign bodies, help diagnose peritonitis and guide surgical treatment.