An unusual case of abdominal pain

Abstract

Free AccessCase of the monthAn unusual case of abdominal painG Ananthakrishnan and J FlinnG AnanthakrishnanSearch for more papers by this author and J FlinnSearch for more papers by this authorPublished Online:28 Jan 2014https://doi.org/10.1259/bjr/22587841SectionsPDF/EPUB ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InEmail AboutA 50-year-old Caucasian woman presented with sudden-onset lower abdominal pain with associated nausea and vomiting. There was a history of hysterectomy and treated breast cancer. Of note, the patient was a vegetarian and a keen traveller.Plain radiography of the abdomen, blood tests and an ultrasound examination were unremarkable.As the patient was still symptomatic, a contrast-enhanced CT of the abdomen was performed after administration of oral contrast (Figure 1). This showed a long tubular intraluminal lesion in the distal small bowel, which was outlined by oral contrast. Segments of this lesion were noted to be air-filled. No other significant abnormality was identified.Figure 1 Coronal oblique CT image shows a partly gas filled intraluminal filling defect in the terminal small bowel, outlined by oral contrast. Download Figure What is the abnormality and what is the diagnosis? What are complications associated with this condition?DiagnosisTubular intraluminal lesion consistent with Ascaris lumbricoides infestation of the small bowel was diagnosed.Small bowel obstruction is one of the commonest complications. Others include cholecystitis, cholangitis, pancreatitis, appendicitis and respiratory symptoms.DiscussionIt is estimated that 25% of the world's population is infected with Ascaris lumbricoides (intestinal roundworm), mostly people in developing countries [1, 2]. The clinical and radiological manifestations of Ascariasis are variable as the organism travels through many organ systems during its life cycle.Respiratory symptoms are usually the first and occur after the larvae penetrate the intestinal mucosa, traverse the portal and hepatic veins, and finally settle in the pulmonary alveoli [1]. Following this, the larvae migrate to the larynx and are swallowed. Larval maturation occurs in the small bowel and patients can present with abdominal symptoms.Although many patients are symptom free during the intestinal phase of the disease, others can present with a variety of symptoms including nausea, vague abdominal discomfort, colicky pain, diarrhoea or obstruction. Migration of the worms into ducts may result in cholangitis, cholecystitis or pancreatitis [1, 3]. Blockage of the lumen of the appendix may lead to appendicitis.CT diagnosis of Ascariasis was first described in 1994 [4], with few subsequent case reports. Reported findings describe a long tubular filling defect with a thin line of contrast occasionally seen in the gut of the worm [4, 5]. If the worm is visualised perpendicular to the imaging plane, a “bull's eye” appearance is seen [6]. Reports have also previously indicated that some of these worms can appear partly air-filled [7] (Figure 2). Diagnostic laparoscopy in our patient was normal.Figure 2 Axial CT of lower abdomen at the same level showing multiple rounded intraluminal filling defects, one of which is air-filled. Download Figure Radiologists must be cautious about dismissing the finding as an artefact or a feeding tube without proper consideration. Although it is not common in developed countries, it should be suspected in patients with a history of travelling.References1 Reeder M , Palmer P . Infections and infestations. In: Freeny PCStevenson GW, editors. Margulis and Burhenne's alimentary tract radiology. St. Louis: Mosby, 1994: 926–30. 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Crossref Medline ISI, Google Scholar Previous article Next article FiguresReferencesRelatedDetailsCited byEpidemiology and management of foodborne nematodiasis in the European Union, systematic review 2000–201629 June 2018 | Pathogens and Global Health, Vol. 112, No. 5 Volume 83, Issue 991July 2010Pages: 543-e164 2010 The British Institute of Radiology History ReceivedDecember 07,2009AcceptedJanuary 26,2010Published onlineJanuary 28,2014 Metrics Download PDF