Clinical History
A 40-year-old gentleman presented with a one week history of right flank pain, associated with a two day history of nausea and diarrhoea. On examination, he was found to be tender in the right lumbar area. Blood tests revealed a WBC of 10.4 x 109/L and CRP of 82.4mg/L.
Imaging Findings
Initial CT showed a small abscess resulting from a localised perforation of the jejunum by a linear focus of high attenuation. It measured 2.3 cm x 2 mm and was highly suspicious for a retained foreign body, most likely a fish bone. On direct questioning, the patient admitted to eating fish on the days prior to his admission.
The patient was managed conservatively with intravenous co-amoxiclav and metronidazole. He improved clinically and was discharged five days later. His inflammatory markers were normal at time of discharge. A repeat CT carried out four weeks post discharge showed resolution of the abscess. The presumed fishbone remained, with one tip intraluminal. On review, the patient remained asymptomatic and the option of a diagnostic laparoscopy was discussed. A decision was made not to proceed with further investigations, unless he became symptomatic, as he was reluctant to proceed with surgical exploration. He has remained well on follow-up.
Discussion
Ingestion of foreign bodies is usually accidental occurring more commonly in those who wear dentures, as the covered soft palate is unable to identify potentially troublesome objects. It also occurs in those with psychiatric disorders, in chronic alcoholics and in children [1]. Ingested foreign bodies commonly pass through the gastrointestinal tract within one week, with less than 1% resulting in intestinal perforation [2]. Perforation may occur at any site; however, the majority arise at sites of narrowing or acute angulation. The small bowel is most commonly affected, with around 83% of documented perforations noted in the ileum [3]. The risk of perforation is directly related to the object’s length and sharpness. The most common offending objects include fish and chicken bones, metal objects and toothpicks. In cases of delayed diagnosis, perforation may lead to intraperitoneal abscess formation. Ingested foreign bodies may even migrate to form liver abscesses [4]. Clinical diagnosis is notoriously difficult as perforation can mimic a variety of other conditions and a proportion of patients may not recall ingesting a foreign object.
On plain films, a radio-opaque object like a fishbone is often masked by overlying structures, as in our case. With the advent of more precise radiological imaging, diagnosis can be made without the need for surgery [5]. However, CT imaging was able to provide us with important information regarding the shape, likely nature and site of perforation. Similar to our case, there have been case reports in the literature describing the conservative management of patients with contained perforations of hollow viscera secondary to ingested foreign objects [6].
In conclusion, cross-sectional imaging lends itself to a more accurate and timely diagnosis of hollow visceral perforations caused by foreign bodies. As in our case, CT proves a valuable tool in the prediction and follow-up of those cases that are suitable candidates for conservative management.
Differential Diagnosis List
Small bowel perforation secondary to an ingested fish bone
Appendix abscess
Diverticular abscess
Crohn abscess
Tumour abscess
Final Diagnosis
Small bowel perforation secondary to an ingested fish bone
