Botulinum A toxin as a treatment for overactive rectum with associated faecal incontinence

Rectal hypercontractility can lead to faecal incontinence (FI). Botulinum toxin (BT) has been used successfully for the treatment of bladder overactivity. This study aimed to evaluate the therapeutic value of intrarectal injections of BT in inhibiting colorectal contractions and relieving FI in patients suffering from FI as a result of overactive rectal contractions.

A prospective open study was carried out in Rouen University Hospital. Six patients (four men and two women) with severe FI related to overactive rectal contractions underwent intrarectal submucosal injections of BT placed in three rows of 10, 1-ml injections (50 U/1 ml; Dysport(®)) starting 1 cm above the dentate line and repeated twice, at intervals of 5 cm proximally. The end-points included improvement in the FI score, in faecal incontinence quality of life (FIQL) and of manometric abnormality.

All patients reported improvement in the FI score [18.2±1.1 at baseline vs 9.0±1.7 at 3 months (P=0.04)] and in FIQL. Rectal contractile activity was reduced. The frequency of contractions remained unaffected (28.1±6.6/h; P=0.46 vs baseline). High-amplitude contractions of >50 cmH(2)O were significantly decreased in all patients (16.6±3.9 vs 6.6±4.1/h; P=0.03).

Patients with an 'overactive rectum' are a heterogeneous group, with varying causes of dysfunction. The dose of BT used was arbitrarily selected. Nevertheless, the study introduces a further therapeutic option in the treatment of FI caused by rectal overactivity.