Abdominal radiograph in the assessment of fecal impaction in children with functional constipation: comparing three scoring systems.

OBJECTIVES To compare three radiological scores in the study of fecal impaction in children with constipation. To investigate whether these radiological scores are useful in the assessment of fecal disimpaction therapy and if they present a relation with total colonic transit time. METHODS The Barr, Blethyn and Leech scores were measured by three observers, independently, in 123 abdominal radiographs. Interobserver agreement in the diagnosis of fecal impaction was calculated for the three scores. In 30 radiographs, the analysis of the scores was performed before and after fecal disimpaction. Total colonic transit time was calculated in 59 radiographs with the use of radiopaque markers. RESULTS The agreement between pairs of observers was assessed by the kappa coefficient and was good for the Barr (0.56, 0.59 and 0.69) and Leech scores (0.53, 0.58 and 0.61). The Blethyn score presented lower kappa coefficients (0.26, 0.32 and 0.36). In the comparison of methods, Leech and Barr showed a good correlation. After fecal disimpaction, there was a statistically significant reduction (p < 0.001) of scores, most significantly with the Barr score. There was no relation between radiographic scores and colonic transit time. CONCLUSIONS There is no relation between fecal impaction assessed by radiography of the abdomen and total colonic transit time. Plain radiographs may be a useful tool for the diagnosis of fecal impaction. The Barr score can be considered a good method of analysis, especially to assess the response to treatment of fecal impaction.