Images in Emergency Medicine
Article Outline
[Ann Emerg Med. 2007;49:e1-e2.]
A 20-year-old Hispanic man complained of crampy periumbilical pain for the last 24 hours, associated with some bloody diarrhea. He had emigrated from Mexico to the United States within the last 3 months. The patient’s vital signs, including a rectal temperature, were normal. His physical examination was remarkable for mild diffuse abdominal tenderness and trace guaiac-positive stool.
Diagnosis
Intestinal ascariasis
A computed tomography (CT) scan of the abdomen was ordered, with oral and intravenous contrast (Figure 1, Figure 2, Figure 3, Figure 4). The scan demonstrated multiple tubular and serpiginous filling defects in the small bowel, suspicious for intestinal parasites. Ascaris lumbricoides ova were found in the patient’s stool specimen. The patient was prescribed oral antibiotics and appropriate follow-up.
Figure 1.
Computed tomographic scan of the abdomen.
Figure 2.
Computed tomographic scan of the abdomen.
Figure 3.
Computed tomographic scan of the abdomen.
Figure 4.
Computed tomographic scan of the abdomen. Used with permission of Blaine Hannafin, MD, Department of Emergency Medicine, Maricopa Medical Center, Phoenix, AZ.
Intestinal ascariasis occurs in individuals who ingest contaminated water or food. In Africa, the Far East, and Central and South America, its prevalence is as high as 90%.1 Infections with Ascaris are frequently asymptomatic, but colicky abdominal pain, weight loss, malnutrition, diarrhea, or even biliary or intestinal obstruction may occur.1, 2
Diagnosis is usually made by examination of a stool specimen for ova. A CT of the abdomen with oral contrast can demonstrate multiple round linear filling defects in the lumen of the small bowel, as was found in this patient.3, 4
In patients who present with an uncomplicated Ascaris infection, outpatient treatment with either a single dose of albendazole 400 mg or mebendazole 500 mg by mouth has been shown to be effective in curing 97% of cases.1
References
- . Ascariasis. Topics Emerg Med. 2003;25:38–43
- . Biliary ascariasis: CT, MR cholangiopancreatography, and navigator endoscopic appearance: report of a case of acute biliary obstruction. Abdom Imaging. 1999;24:470–472
- . CT findings in pediatric gastrointestinal ascariasis. Comput Med Imaging Graph. 1997;21:47–49
- . Intestinal ascariasis: CT findings and diagnosis. South Med J. 2006;99:317–318
For the diagnosis and teaching points, see page e2.
PII: S0196-0644(06)00957-7
doi:10.1016/j.annemergmed.2006.07.002
© 2007 American College of Emergency Physicians. Published by Elsevier Inc. All rights reserved.
