CASE 11605 Published on 11.03.2014

An unexpected cause of abdominal pain

Section

Abdominal imaging

Case Type

Clinical Cases

Authors

La Pietra P, Sommario M, Baroncelli A, Jannaci M°

Ospedale Bentivoglio,
Asl Bologna,
Dipartimento servizi;
Via Marconi
40121 Bentivoglio, Italy;
Email:plapietra@tin.it
°Ospedale Bentivoglio,
Asl Bologna,
Dipartimento Chirurgia;
Via Marconi
40121 Bentivoglio
Patient

89 years, male

Categories
Area of Interest Abdomen ; Imaging Technique Conventional radiography, Ultrasound, CT, Image manipulation / Reconstruction
Clinical History
A 89-year-old man was admitted to E.R. for onset of abdominal pain localized to the right flank. Clinical examination revealed mild tenderness in right flank and the routine laboratory showed moderate eosinophilia and elevation of inflammatory parameters.
Imaging Findings
The abdominal radiograph at admittance showed few small air-fluid levels localized tin the right flank. The ultrasound examination noted a well-defined segmental thickening of an ileal loop, predominantly hypoechogenic with central hyperechoic structures without posterior acoustic shadowing. To obtain a more precise diagnosis, an enhanced multidetector CT was performed, which confirmed the segmental thickening of an ileal loop with intense enhancement after contrast medium administration.
Fat stranding was present in the adjacent thickened bowel loop and a low attenuation linear image could be seen within the lumen.
A diagnosis of segmental inflammation of small bowel was suggested. Because of worsening of abdominal pain and the undetermined aetiology of the illness the patient underwent surgery. Inside the lumen of the resected ileal loop a tapeworm was found, which turned out to be a taenia saginata. The patient remembered that several weeks before he had been eating raw beef.
Discussion
Taeniasis is a rare condition caused by the presence of a ribbon-like parasite in the human intestines, belonging to the class of cestodes and named tapeworm. Three species of tapeworms can infest humans: taenia solium, taenia saginata and taenia asiatica [1]. The taenia saginata is the most frequent form in developed countries; is also called beef tapeworm because humans may get infected by eating raw or undercooked meat of cattle infected with larval forms of the parasite [2]. The adult tapeworm consists of a head called scolex and numerous segments called proglottids; these contain mature eggs that are passed through human faeces, contaminating the pastures. When eating the infected vegetation, the cattle ingests the embryonated eggs called oncospheres, which then hatch in the alimentary canal, liberating the larvae. These pierce the gut wall and enter the circulatory system, which enables them to reach all parts of the animal body where they develop cysticercus, a cyst that contains protoscolices. When the viable larva is ingested, it evolves in the small bowel of humans within 7-8 weeks into an adult taenia, which closes the lives cycle of the parasite [1, 2, 3]. Over time, the tapeworm can reach several meters in length; in our case the short time since ingestion of the larvae explains the smaller length of the tapeworm.
Taeniasis is frequently asymptomatic, rarely causing abdominal pain, nausea, variations of appetite, constipation and diarrhoea. The pathognomonic sign reported by patients is the passage of tapeworm segments through the anus [2-4]. If this sign is absent the diagnosis is very difficult.
Generally imaging studies are not required because the diagnosis is made with a stool examination that detects eggs and proglottids; however, they may be required because of the nonspecificity of symptoms, or complications such as appendicitis, obstruction of bile or pancreatic duct, bowel obstruction or perforation [5-6]. The intestinal barium studies are able to demonstrate a linear continuous filling defect along the intestinal lumen showing the tapeworm [7-8].
Even with the modern imaging techniques such as ultrasound, computed tomography and magnetic resonance an anomalous content of the intestinal lumen can be detected, which the radiologists often misinterpret because of their limited experience with this rare disease [9]. On abdominal imaging studies it is essential to consider not just the pathologic changes of parietal thickness or of the mucosal layer but also the intraluminal filling defects that may occur in some diseases.
Medical treatment with praziquantel or niclosamide can solve most of cases [4]; surgery is an option for the not diagnosed symptomatic cases. The complicated cases require surgical treatment anyway. The prognosis is good.
Differential Diagnosis List
Taeniasis by taenia saginata
Crohn\'s disease
Ischaemic enteritis
Final Diagnosis
Taeniasis by taenia saginata
Case information
URL: https://www.eurorad.org/case/11605
DOI: 10.1594/EURORAD/CASE.11605
ISSN: 1563-4086