1. Enfermedad de
Hirschprung
o
Megacolon Congenito
5to C
2. Que es?????
• Consiste en una ausencia de
células
• Ganglionares
• Ganglios nerviosos
• En la pared
− Muscular
− Submucosa
3. Porque??
• Detención en la migración
caudal de las células
procedentes de la cresta neural
antes de llegar al ano
• Desarrollo embrionario
4.
5. Incidencia
• 1 de cada 5,000
• 70% a 80%
• Masculinos
• Menos frecuente en la
raza negra
• Antecedente +
• Mayor riesgo de
padecerla
• Malformaciones
agregadas
• 25% de los casos con
antecedes familiares
• 10% no familiar (sin
antecedentes)
6. Factores Genéticos
• Se descubrió una paciente
femenina con aganglionosis
total del colon
• Sindrome de Zuelzer-Wilson
• portaba una deleción en el
cromosoma
• 10:46,XX de q110.11.21-q21.2
7. Tres genes
• Identificados en el
hombre
2. Gen de RET
– Cromosoma 10
• Autosómicos
dominante
3. Gen EDNRB
– Gen del receptor de la
endotelina B
– Cromosoma 13
– Autosómicos Recesivo
4. Gen EDN3
• Gen de endotelina 3
• Cromosoma 20
− Autosómicos recesivo
8. Fisiopatología
• Intestino Fisiopatología
• Falta de
propagación de las
ondas de propulsión
Intestino Esfínter anal Interno
• Esfínter anal
interno
• Relajación anormal Falta de ondas
Relajación anormal
O ausencia de la
• Ausencia de la peristalticas
relajación
relajación
Aganlionosis
Hipoganglionosis
Disganglionosi
9.
10. Cuadro Clinico
• 3 Puntos Cardinales
1. Ausencia de evacuacion en las
primeras 24 hrs de vida
2. Distension Abdominal
3. Vomito
11. Examen Rectal
• Con sonda rectal,
termometro o
lavados
• Induce a la salida
explosiva de heces
liquidas y gas
sospechoso a
enterocolitis
• Se nota hipertonía
del esfínter rectal y
casi siempre esta
vacío
12. • Se ha visto que la
ENTEROCOLITIS se presenta en
un 12% a 58% de los pacientes
con megacolon congénito
13. Enterocolitis
• Hipotesis Etiologicas
1. Estasis fecal
• Isquemia en mucosa
• Invasion y
traslocacion de
bacteriana.
• Alteracion de las de
la composicion de la
mucina y
mecanismos de
defensa de la
mucosa
• Aumento de la
actividad de la
prostaglandina E1 y
la infeccion por
Clostridium difficile
14. Forma grave de
enterocolitis
• Megacolon toxico
• Caracterizado por:
1. Fiebre
2. Vomito teñido de bilis
3. Diarrea explosiva
4. Distensión abdominal
5. Deshidratación
6. Choque
15. Diagnostico
• Radiologico
• Radiografia
abdominal
• Posicion Supina
y verticla
• Muestran niveles
Hidroaereos en
colon
Hallazgo tipico
19. Electromanometria
Rectal
• Precisión diagnostica
• 85%
• Normalmente
• Se produce relajacion
del esfínter anal
interno
• EH
• Muestran cambios
característicos
durante el estimulo
• En la presión del
conducto anal
• Parte inferior del
recto
20. Biopsia Rectal
Tinción de hematoxilina y eosina • Se toman
muestras de
• 2, 3, 5 cm
• Muestra optima
• 3.5 cm de
diametro
• Incluye
submucosa
22. Tratamiento
• Descompresión
1. Instalación de una sonda nasogastrica.
2. Vaciamiento repetido del recto con
sonda rectales e irrigaciones.
− Después de hacer todos los métodos
diagnósticos
– Se procede a establecer un estoma, si es
necesario.
23. Tratamiento
• Colostomía
• Antes de realizarla
es necesario
1. Lavado
intestinal
2. Administracion
de antibioticos
30 minutos
antes de la
operación
3. Instalación de
una sonda
ureteral
25. Técnica
• For Swenson’s pull-through operation the vessels are electro-coagulated under
patient is positioned on the operating direct vision. Sufficient tension-free
table to provide simultaneous exposure length is obtained by dividing the
of the perineum and abdomen. The pelvis inferior mesenteric pedicle, carefully
is allowed to drop back over the lower preserving the marginal vessels.
end of the table and the legs are strapped Dissection is carried down to the
over sandbags. A Foley catheter is level of the external sphincter
inserted into the bladder. The abdomen is posteriorly and laterally, but does not
opened via a paramedian incision. Some extend as deeply anteriorly,
surgeons prefer a Pfannenstiel incision leaving around 1.5 cm of intact rectal
when performing a Swenson’s pull- wall abutting against the vagina or
through operation in the neonate. urethra. The mobilized rectum is
Extramucosal biopsies are taken at intussuscepted through the anus by
intervals along the antimesenteric border passing a curved clamp or a Babcock
and assessed by frozensection to forceps through the anal canal; an
determine the level of assistant places the closed rectal
ganglionatedbowel. The sigmoid colon is stump within the jaws of the clamp.
mobilized by dividingthe sigmoid vessels When the dissection has been
and retaining the marginalvessels.It may completed, it should
be necessary to mobilize the splenic
flexureto obtain adequate length. The be possible to evert the anal canal
proximal level ofresection above the completely when traction is applied
ganglionated level, previouslydetermined to the rectum.An incision is made
by frozen section, is selected and the anteriorly through the rectal wall
bowel is divided between intestinal about 1 cm from the dentate line,
clamps or staples. The peritoneum is extending halfway through the rectal
divided around its lateral andanterior circumference.A clamp is inserted
reflection from the rectum, exposing through this incision to grasp
themuscle coat of the rectum.At this multiple sutures placed through the
point, the bowel isdivided at the cut end of the proximal colon. An
rectosigmoid junction and outer layer of interrupted 4-0
removed.Dissection extends around the absorbable sutures is placed through
rectum, keeping veryclose to the bowel the cut muscular edge of the rectum
wall. It is essential to maintain and the muscular wall
thedissection close to the muscular wall of the pull-through colon.When the
in order to preventdamage to the pelvic outer layer has been completed, the
splanchnic innervation.All proximal bowel is opened and an
inner layer of interrupted 4-0
absorbable suturesis
placed.When anastomosis is
27. Tecnica
The advantage of the Duhamel pull-through is that very little
manipulation of the rectum is performed anteriorly thus avoiding
injury to the genitourinary innervation. The rectum is divided and
closed just above the peritoneal reflection. The redundant
aganglionic bowel is resected. The retrorectal space is created
by blunt dissection down to the pelvic floor. The posterior rectal
wall is incised 1.5 to 2 cm above the dentate line and sponge
holding forceps is inserted into the retrorectal space and
ganglionic bowel pulled through. The anterior half of the
pulledthrough ganglionic bowel is anastomosed to the posterior
wall of the aganglionic rectum and remainder of the colo-rectal
anastomosis completed by approximating the aganglionic
rectum to the posterior wall of the pulled-through ganglionic
bowel. Finally an extra long automatic stapling device is used to
complete the side to side anastomosis between the aganglionic
rectum and the ganglionic pulled-through bowel. Some surgeons
complete the side to side anastomosis prior to closing the rectal
stump, thereby preventing any residual septum.
29. Técnica
In Soave or endorectal pull-through the first steps of
the operation are similar to those described for
Swenson’s or Duhamel operation. The colon is
mobilized and resected about 4 cm above the
peritoneal reflection. The endorectal dissection
begins 2 cm below the peritoneal reflection. The
seromuscular layer is incised circumferentially and
the mucosal-submucosal tube is freed distally. The
mucosal dissection iscontinued distally to the level
of the dentate line. Themucosa is incised
circumferentially 1 cm above thedentate line. A
Kelly clamp is inserted from belowand the
ganglionic bowel is pulled
through.Coloanalanastomosis is completed using
4/0 absorbable sutures.
31. Técnica
Rehbein’s technique differs from
the Swenson’s procedure,in that
the anastomosis is a low,
anterior colorectal
anastomosis. In this procedure,
3 to 5 cm of the terminal
aganglionic rectum is left
behind,which is anastomosed to
the ganglionic bowel.
32. Bibliografía
• CIRUGIA PEDIATRIA
ASCHRAFT Murphy, Sharp,
Sigalet, Snyder
• SPRINGER SURGERY ATLAS
SERIES Series Editors: J. S.
P. Lumley · J. R. Siewert
