Overlooking the abdominal X-ray--the peril of ascariasis.
Abstract: A young child presented with intermittent bowel obstruction. The abdominal X-ray was not closely examined, and a contrast study was performed that demonstrated multiple tubular filling defects indicative of worms. The patient was treated accordingly. Reviewing the abdominal X-ray demonstrated numerous serpigenous, tubular, soft-tissue densities in gas-filled bowel loops.
Article Type: Case study
Subject: Ascariasis (Diagnosis)
Ascariasis (Case studies)
X-rays (Usage)
Authors: Mahomed, N.
Docrat, Z.
Mkhonza, L.
Keating, L.
Pub Date: 02/01/2012
Publication: Name: South African Journal of Surgery Publisher: South African Medical Association Audience: Academic Format: Magazine/Journal Subject: Health Copyright: COPYRIGHT 2012 South African Medical Association ISSN: 0038-2361
Issue: Date: Feb, 2012 Source Volume: 50 Source Issue: 1
Geographic: Geographic Scope: South Africa Geographic Code: 6SOUT South Africa
Accession Number: 281375518
Full Text: A 9-year-old boy presented with intermittent bowel obstruction. The abdominal X-ray (Fig. 1) was initially overlooked and a contrast study (Fig. 2) was performed that demonstrated multiple tubular filling defects in the stomach, duodenum and proximal small bowel consistent with worms. The patient was treated for worms which he subsequently passed and his symptoms improved. Re-evaluation of the abdominal X-ray demonstrated numerous serpigenous, tubular, soft-tissue densities in gas-filled bowel loops in the left mid and lower quadrants.

The abdominal X-ray has a sensitivity of 70% in the detection of worms. Large collections of worms may be visualised on plain film, outlined by intestinal gas, with the interface between the worm bolus and adjacent gas shadows appearing irregular. Isolated worms may be visualised as linear or bubble-shaped radiolucencies, indicating the presence of gas within the lumen of the worm. (1) Worms may appear as areas of tubular, linear soft-tissue densities in gas-filled bowel loops on abdominal X-ray, as in our patient. (2) Radiographs can also demonstrate bowel obstruction and free gas under the diaphragm in patients with intestinal perforation. (1)

[FIGURE 1 OMITTED]

On barium studies, worms appear as filling defects that are cylindrical, elongated and smooth within the contrast-filled intestinal lumen. In fasting patients, worms may ingest the contrast, resulting in outlining of their alimentary canals. (3)

The specific features of worms should not be overlooked on abdominal X-ray, thereby avoiding the radiation dose, discomfort and cost of contrast studies.

[FIGURE 2 OMITTED]

REFERENCES

(1.) Ellman BA, Wynne JM, Freeman A. Intestinal ascariasis: New plain film features. AIR 1980; 135: 37-42.

(2.) Khan EA, Khalid A, Hashmi I, Jan IA. Gastrointestinal obstruction due to ascariasis - management issues. Inf Dis I Pakistan 2008; 17: 72-74.

(3.) Das CJ, Kumar J, Debnath J, Chaudhry J. Imaging of ascariasis. Austr Radiol 2007; 51: 500-506.

N. Mahomed, M.B. B.Ch., F.C.Rad. (Diag.) S.A.

Z. Docrat, M.B. B.Ch.

L. Mkhonza, M.B. B.Ch.

L. Keating, M.B. B.Ch.

Department of Radiology, Chris Hani Baragwanath Hospital and University of the

Witwatersrand, Johannesburg
Gale Copyright: Copyright 2012 Gale, Cengage Learning. All rights reserved.