Rectal hyposensitivity

Abstract

Impaired or blunted rectal sensation, termed rectal hyposensitivity (RH), which is defined clinically as elevated sensory thresholds to rectal balloon distension, is associated with disorders of hindgut function, characterised primarily by symptoms of constipation and fecal incontinence. However, its role in symptom generation and the pathogenetic mechanisms underlying the sensory dysfunction remain incompletely understood, although there is evidence that RH may be due to 'primary' disruption of the afferent pathway, 'secondary' to abnormal rectal biomechanics, or to both. Nevertheless, correction of RH by various interventions (behavioural, neuromodulation, surgical) is associated with, and may be responsible for, symptomatic improvement. This review provides a contemporary overview of RH, focusing on diagnosis, clinical associations, pathophysiology, and treatment paradigms.

Keywords: Constipation; Fecal incontinence; Rectal hyposensitivity.

Figure

Sensory pathways from the rectum to the higher cortical centers (reproduced from Sharma et al with permission: Sharma A, Lelic D, Brock C, Paine P, Aziz Q. New technologies to investigate the brain gut axis. World J Gastroenterol 2009;15:182-191). pACC, perigenual anterior cingulate cortex; MCC, mid cingulate cortex; INS, insular; SI, somatosensory cortex. Arrows indicate visceral distension.