Gonyautoxin: new treatment for healing acute and chronic anal fissures.
OBJECTIVE
The mayor symptoms of chronic anal fissure are permanent pain, intense pain during defecation that lasts for hours, blood in the stools, and sphincter cramps. It is subsequent to formation of fibrosis infiltrate that leads to an increased anal tone with poor healing tendency. This vicious circle leads to fissure recurrence and chronicity. This study was designed to show the efficacy of gonyautoxin infiltration in healing patients with anal fissures.


METHODS
Gonyautoxin is a paralyzing phytotoxin produced by dinoflagellates. Fifty recruited patients received clinical examination, including proctoscopy and questionnaire to evaluate the symptoms. Anorectal manometries were performed before and after toxin injection. Doses of 100 units of gonyautoxin in a volume of 1 ml were infiltrated into both sides of the anal fissure in the internal anal sphincter.


RESULTS
Total remission of acute and chronic anal fissures were achieved within 15 and 28 days respectively. Ninety-eight percent of the patients healed before 28 days with a mean time healing of 17.6 +/- 9 days. Only one relapsed during 14 months of follow-up. Neither fecal incontinence nor other side effects were observed. All patients showed immediate sphincter relaxation. The maximum anal resting pressures recorded after two minutes decreased to 56.2 +/- 12.5 percent of baseline.


CONCLUSIONS
Gonyautoxin breaks the vicious circle of pain and spasm that leads to anal fissure. This study proposes gonyautoxin anal sphincter infiltration as safe and effective alternative therapeutic approach to conservative, surgical, and botulinum toxin therapies for anal fissures.
Garrido
Rogelio
R
Departamento de Cirugia, Seccion Proctologia, Hospital Clinico Universidad de Chile, Casilla 70005, Corrreo 7, Santiago, Chile.
Lagos
Nestor
N
Lattes
Karinna
K
Abedrapo
Mario
M
Bocic
Gunther
G
Cuneo
Aldo
A
Chiong
Hector
H
Jensen
Christian
C
Azolas
Rodrigo
R
Henriquez
Ana
A
Garcia
Carlos
C
D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D002908:Chronic Disease; D004141:Dinoflagellida; D004311:Double-Blind Method; D005260:Female; D005401:Fissure in Ano / Q000188:drug therapy*; D006801:Humans; D008297:Male; D008365:Manometry; D008387:Marine Toxins / Q000627:therapeutic use*; D008875:Middle Aged; D010147:Pain Measurement; D012530:Saxitoxin / Q000031:analogs & derivatives* / Q000627:therapeutic use*; D016896:Treatment Outcome
D008387:Marine Toxins; D012530:Saxitoxin; C013007:gonyautoxins