Rectal measurements and their correlation with bowel habits: Evaluation by trans‐abdominal ultrasound in children with functional constipation

Abstract

Aim Constipation is one of the most common complaints in childhood affecting the quality of life of both children and parents. This study intends to investigate rectal measurements on ultrasound and their relationship with bowel habits. Methods In this cross‐sectional study, 100 children with functional constipation (FC) referred to a single hospital between 2018 and 2019 were enrolled. After obtaining informed consent, a questionnaire including demographic and constipation characteristics was completed, and a physical examination including digital rectal examination (DRE) was performed. Complete abdominopelvic ultrasound was then performed. Target measurements included rectal transverse diameter (RTD), rectal anterior wall thickness (RAWT) and the presence of faecal impaction. Results One hundred children with a mean age of 7.68 ± 3.30 years were present in the study. The mean duration of constipation was 15.86 ± 13.34 months. In 14% of children, painful defaecation was reported. 88% of children had some degree of faecal incontinence. According to the ultrasound findings, the mean RTD and RAWT were 3.39 ± 0.73 cm and 2.77 ± 0.68 mm, respectively, and faecal impaction was present in 70% of cases. There was a positive correlation between RTD and RAWT with age, duration of constipation and the presence of hard stools, and there was a negative correlation with frequency of defecation (P < 0.05). Conclusion RTD and RAWT increased with increasing constipation duration and the presence of hard stools and decreased with increasing frequency of defaecation. DRE could be omitted from the initial clinical assessment if you had access to reliable ultrasound data.

The role of rectal ultrasound in children with functional constipation

“…We could only find a moderate correlation between rectal diameter and duration of symptoms, comparable to other studies. 14,17 And unlike studies performed by Pop et al 15 and Shapouri et al 8 Regression analysis to predict dilated rectal diameter also confirmed this relation; however, other parameters were not significant.…”

“…Few studies addressed a relation between age and rectal diameter. A positive correlation was specifically obvious in those studies addressing a wide age range including infants 5,8,13,15 . Karaman et al .…”

“…A positive correlation was specifically obvious in those studies addressing a wide age range including infants. 5,8,13,15 Karaman et al also supported this idea although the included children were elder than 4 years. 14 Other studies found no correlation between age and TRD, this is because they did not include patients younger than 4 years.…”

“…4 A non-invasive and dependable substitute in evaluating the rectal filling state is the echo-sonographic measurement of transverse rectal diameter, which could potentially supersede digital rectal examination. [5][6][7][8] Although diagnosis of constipation is based on history and physical examination, subjective symptom description is unreliable in infants and many children. 4 Given these limitations, clinicians often perform abdominal radiographs to support the diagnosis of constipation and exclude other pathology.…”

“…Nevertheless, diagnosis of FC may prove difficult, particularly if only one criterion is positive, and in such cases, digital rectal examination is indicated to determine the presence of faecal impaction 4 . A non‐invasive and dependable substitute in evaluating the rectal filling state is the echo‐sonographic measurement of transverse rectal diameter, which could potentially supersede digital rectal examination 5–8 …”