Scintigraphy evaluation of the types of functional constipation in children with bowel bladder dysfunction

To evaluate the types of constipation according to colonic transit time in chronically constipated children with dysfunctional voiding (bowel bladder dysfunction, BBD group) and to compare the results with transit type in children with chronic functional constipation without urinary symptoms (constipation group) and children with normal bowel habits, but with lower urinary tract symptoms (control group).

One-hundred and one children were included and their medical histories were obtained. The BBD group kept a voiding diary, and underwent urinalyses and urine culture, ultrasound examination of bladder and kidneys and uroflowmetry with pelvic floor electromyography. Radionuclear transit scintigraphy was performed in all children according to a standardized protocol. Patients were categorized as having either slow-transit (ST), functional fecal retention (FFR) or normal transit.

FFR was diagnosed in 31 out of 38 children with BBD, and 34 out of 43 children in the constipation group. ST was found in seven children with BBD, compared with nine children in the constipation group. The control group children demonstrated normal colonic transit. Urgency, daily urinary incontinence and nocturnal enuresis were noted only in children with FFR. Both children with ST constipation and FFR complained of difficulties during voiding, voiding postponement and urinary tract infections.

FFR is the most common form of constipation in children with dysfunctional voiding. However, some children might suffer from ST constipation. Differentiation between these two types of constipation is clinically significant because they require different treatment. Future studies with larger numbers of patients are needed to confirm the noted differences in urological symptoms in these two groups of constipated children..