Sensitivity of the sigmoid colon and rectum in children treated for chronic constipation

Area of Science:

• Pediatric Gastroenterology
• Neurogastroenterology
• Colorectal Physiology

Background:

• Chronic constipation is a common pediatric issue.
• Altered rectal sensation is hypothesized to contribute to functional constipation.
• Understanding sensory processing in the sigmoid and rectum is crucial for pediatric constipation management.

Purpose of the Study:

• To investigate rectal and anal canal sensory perception in children with chronic constipation compared to healthy controls.
• To evaluate the persistence of sensory abnormalities after treatment and recovery.

Main Methods:

• Utilized latex balloons and pressure transducers to measure sensations in the sigmoid and rectum.
• Assessed the anal canal's response to balloon distension in 15 constipated and 15 healthy children.
• Restudied a subset of constipated children 7-12 months and 3 years post-treatment.

Main Results:

• Constipated children exhibited significantly higher thresholds for fullness, critical volume, and constant relaxation compared to controls.
• These sensory deficits persisted at 1 and 3-year follow-ups, even in recovered children.
• Rectal enlargement in constipated children may impair the sensation of fullness and the defecation reflex.

Conclusions:

• Children with chronic constipation demonstrate persistent abnormalities in sigmoid and rectal sensitivity, irrespective of clinical improvement or normalized rectal size.
• These persistent sensory deficits may underlie the high vulnerability to constipation recurrence and fecal soiling in this population.
• The findings support a neurophysiological basis for chronic constipation in children, highlighting the importance of sensory processing in the rectosigmoid.