Identifying faecal impaction is important for ensuring the timely diagnosis of childhood functional constipation

Most research on functional constipation has been carried out at a tertiary level. We focused this study on a secondary-level hospital outpatients' department, assessing the distribution of diagnostic criteria for childhood functional constipation and evaluating the consequences of current diagnostic practice based on current guidelines.

We enrolled 235 children, aged two to 16 years of age, with functional constipation according to the Rome III criteria and assessed them using medical histories and physical examinations, including rectal examinations and ultrasound measurements of rectal diameter. Faecal impaction was a rectal diameter exceeding 3 cm.

The most frequently reported symptom was painful bowel movements (72.3%) and 39.1% had faecal incontinence. Rectal examination identified faecal impaction in 149 children (66.2%), and ultrasound showed a mean rectal diameter of 3.4 ± 0.6 cm, compared to 2.2 ± 0.6 cm in children without impaction (p < 0.001). Of the 149 children with faecal impaction, 19 (12.8%) only had one additional Rome III criterion. The rectal diameter exceeded 3 cm in 79.9% of cases.

Identifying faecal impaction is important for ensuring the timely diagnosis of childhood functional constipation at the secondary care level. Ultrasound examination proved a reliable alternative to rectal examination or abdominal radiography when identifying faecal impaction.