Treatment with botulinum toxin in children with chronic anal fissure

Chronic anal fissures with painful defecation and bloodstained stools can be seen in children of all ages. Constipation may precede or appear in connection with the symptoms. Adult patients with anal fissures have been treated successfully with the injection of botulinum toxin into both the internal and external sphincter. The effect of botulinum toxin is reversible and lasts for 3-4 months. This pilot study attempted to examine whether botulinum toxin is also effective in paediatric cases of anal fissure, a treatment which not yet has been reported in the literature.

Six boys and seven girls aged 1-10 years were treated with botulinum toxin (Botox ((R))) during 2002-2005 due to chronic anal fissure. Conventional treatment with laxatives and local anaesthetics had been unsuccessful in all cases. The treatment was given to five children under 2 years of age in a dosage of 1.25 Ux2. Eight children over 2 years of age were given 2.5 Ux2. The injections were given in the external sphincter on both sides of the fissure using EMG-stimulation for guidance and were performed under light anaesthetics (Diprivan ((R))). Follow-up was conducted at 1 and 3 months after treatment.

Within one week, 11 of the children were free from pain and blood stained stools, according to their parent's observations. One 10-year old patient initially showed some improvement but soon experienced a recurrence. After another injection with a higher dosage 2 months later, the fissure healed. One 4-year old patient did not show any signs of improvement. The laxatives, which had been withdrawn after the injection treatment, were then reinstated. At the 3 month post-treatment examination the patient was finally symptom-free with no signs of a fissure. There were no negative side-effects detected in any of the cases. Seven recurrences were noted in 6 of the patients after 3-30 months, often in connection with an episode of constipation. Repeat injections were offered and accepted by four of these patients, once more producing good immediate results.

Treatment with botulinum toxin in the external sphincter produces a quick and effective alleviation of pain with healing of chronic anal fissures in children. The treatment is not considered to carry any risks but requires light anaesthesia. Recurrences are common after the pharmacological effect has receded but can be cured with an additional injection.