title: Internal anal sphincter achalasia in children: clinical characteristics and treatment with Clostridium botulinum toxin.
abstract: OBJECTIVE
  To describe the clinical characteristics of children with internal anal sphincter (IAS) achalasia and to evaluate the benefit of intrasphincteric injection of Clostridium botulinum toxin.
  
  
  METHODS
  Retrospective review of the medical records of 20 patients (8 male, mean 5.8 +/- 4.2 years) with severe chronic constipation and IAS achalasia. Each patient received four-quadrant, intrasphincteric injections of botulinum toxin at a dose of 15-25U per quadrant. Patients were reassessed 4 weeks-18 months after injection. We compared the clinical characteristics of these patients to 20 consecutive children (14 male, mean age 8.1 + 4.6 y) with functional constipation (control group).
  
  
  RESULTS
  The children with IAS achalasia had earlier onset of symptoms, less fecal soiling, and less withholding behavior than the control children. Response to botulinum injection was rated excellent by the parents in 60% and by the physician in 35% of children. There was wide individual variability in the frequency of defecation after therapy. Duration of response ranged from 1 week to 18 months.
  
  
  CONCLUSIONS
  Children with IAS achalasia have clinical characteristics differentiating them from children with functional constipation. Intra-anal injection of botulinum toxin is a safe and effective short-term treatment for these children.
authors.affiliation: Department of Pediatric Gastroenterology and Surgery, Children's Hospital of Pittsburgh, 3705 Fifth Avenue at De Soto Street, Pittsburgh, PA 15213, USA.
authors.forename: Paola
authors.initials: P
authors.lastname: Ciamarra
authors.forename: Samuel
authors.initials: S
authors.lastname: Nurko
authors.forename: Edward
authors.initials: E
authors.lastname: Barksdale
authors.forename: Steven
authors.initials: S
authors.lastname: Fishman
authors.forename: Carlo
authors.initials: C
authors.lastname: Di Lorenzo
mesh_terms: D001003:Anal Canal / Q000187:drug effects* / Q000503:physiopathology; D019274:Botulinum Toxins, Type A / Q000494:pharmacology / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D003248:Constipation / Q000188:drug therapy*; D003672:Defecation / Q000187:drug effects* / Q000502:physiology; D005260:Female; D006801:Humans; D007273:Injections, Intramuscular; D008297:Male; D009130:Muscle, Smooth / Q000187:drug effects; D009465:Neuromuscular Agents / Q000494:pharmacology / Q000627:therapeutic use*; D012002:Rectal Diseases / Q000188:drug therapy*; D012008:Recurrence; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D009465:Neuromuscular Agents; D019274:Botulinum Toxins, Type A