Effectiveness of senna vs polyethylene glycol as laxative therapy in children with constipation related to anorectal malformation.
OBJECTIVE
Constipation is present in 80% of children with corrected anorectal malformations, usually associated to rectal dilation and hypomotility. Osmotic laxatives are routinely used for idiopathic constipation. Senna is a stimulant laxative that produces contractions improving colonic motility without affecting the stool consistency. We designed this trial to study the effectiveness of Senna versus polyethylene glycol for the treatment of constipation in children with anorectal malformation.


METHODS
A randomized controlled crossover design clinical trial, including a washout period, was conducted, including children with corrected anorectal malformations with fecal continence and constipation. The sample size was calculated for proportions (n=28) according to available data for Senna. Effectiveness of laxative therapy was measured with a three variable construct: 1) daily bowel movement, 2) fecal soiling, 3) a "clean" abdominal x-ray. Data analysis included descriptive statistics and a Fisher's exact test for the outcome variable (effectiveness).


RESULTS
The study was terminated early because the interim analysis showed a clear benefit toward Senna (p = 0.026). The sample showed a normal statistical distribution for the variables age and presence of megarectum. The maximum daily dose of Senna (sennosides A and B) was 38.7mg and 17g for polyethylene glycol. No adverse effects were identified.


CONCLUSIONS
Therapy with Senna should be the laxative treatment of choice as part of a bowel management program in children with repaired anorectal malformations and constipation, since the stimulation of colonic propulsion waves could lead to stool evacuation without modification of its consistency which can affect fecal continence.


METHODS
I - randomized controlled trial with adequate statistical power.
Department of General Pediatric Surgery, Instituto Nacional de Pediatría, Ciudad de México, Mexico 04530. Electronic address: santosjasso@hotmail.com.
Karla Alejandra
KA
Santos-Jasso
Department of Medical Research, Instituto Nacional de Pediatría, Ciudad de México, Mexico 04530.
José Luis
JL
Arredondo-García
Department of General Pediatric Surgery, Instituto Nacional de Pediatría, Ciudad de México, Mexico 04530.
Jorge
J
Maza-Vallejos
Department of General Pediatric Surgery, and Cochrane Center, Hospital Infantil de México Federico Gómez, Mexico.
Pablo
P
Lezama-Del Valle
D000293:Adolescent; D000071056:Anorectal Malformations / Q000150:complications*; D002400:Cathartics / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D003248:Constipation / Q000188:drug therapy* / Q000209:etiology; D018592:Cross-Over Studies; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D054368:Laxatives / Q000627:therapeutic use*; D008297:Male; D011092:Polyethylene Glycols / Q000627:therapeutic use*; D012676:Senna Extract / Q000627:therapeutic use*; D000081226:Sennosides; D016896:Treatment Outcome
D002400:Cathartics; D054368:Laxatives; D000081226:Sennosides; D011092:Polyethylene Glycols; D012676:Senna Extract
Anorectal malformation; Constipation; Osmotic laxative; Polyethylene glycol; Senna; Stimulant laxative