Comparison of 2-view abdominal radiographs with ultrasound in children with suspected intussusception.

BACKGROUND

The clinical presentation of intussusception is variable; therefore, screening with either abdominal radiography (AXR) or abdominal ultrasound (US) is often used, although the optimal method is not known.

PURPOSE

This study aimed to compare the utility of AXR with that of the US in children with suspected intussusception.

METHODS

Retrospective cohort of children age 3 months to 3 years presenting to a pediatric emergency department (ED) between 2007 and 2009. Inclusion criteria were as follows: (1) presentation to the ED for suspected intussusception and (2) both 2-view AXR and US performed during the ED visit. An AXR was deemed negative for intussusception if air was visualized in the ascending colon on 2 views and transverse colon on the supine view; US results were obtained from the radiologist report at the time of presentation. Criterion standard measures for intussusception were contrast enema, operative report, or follow-up.

RESULTS

A total of 286 children were included, with mean (SD) age 16.1 (9.1) months; 62.2% were male, and 43.7% were African American. Intussusception was present in 61 subjects (21.3%). Abdominal radiography had sensitivity of 62.3% (95% confidence interval [CI], 50.1%-74.5%) and specificity of 86.7% (95% CI, 82.2%-91.1%), whereas US had a sensitivity of 98.4% (95% CI, 95.2%-100.0%) and specificity of 96.4% (95% CI, 94.0%-98.9%). Ultrasound had a greater negative predictive value (99.5%; 95% CI, 98.6%-100.4%) compared with AXR (89.4%; 95% CI, 85.4%-93.5%). Abdominal radiography had a greater false-positive rate (13.3% vs 3.6%) and greater false-negative rate (37.8% vs 1.6%), compared with US.

CONCLUSIONS

Ultrasound is superior to AXR as a screening method for establishing and excluding the diagnosis of intussusception. The poor test characteristics of 2-view AXR suggest that it should not be used as a primary screening method in cases of suspected intussusception.