Although this condition is described by Ruysch in 1691 and popularized by Hirschsprung in 1886, the pathophysiology is not clearly defined until the mid-20th century, when Whitehouse and Kernohan described the aganglionosis of the distal colon as the cause of obstruction in their series Patients. In 1949, Swenson described the first definitive procedure for Hirschsprung's disease is consistent, rectosigmoidectomy with coloanal anastomosis. Since then, other operations have been described, including the Duhamel and Soave technique. (Lee, 2009)
Recently, advances in surgical techniques, including minimally invasive procedures, and earlier diagnosis have resulted in decreased morbidity and mortality for patients with Hirschsprung's disease. Most cases of Hirschsprung's disease is now diagnosed in the newborn period. Hirschsprung disease should be considered in any newborn who fails to pass meconium within 24-48 hours after birth. Although contrast enema is useful in establishing the diagnosis, full thickness rectal biopsy remains the standard criteria. Once the diagnosis is confirmed, the basic treatment is to remove intestinal aganglionik less functional and create the distal anastomosis to the rectum with the healthy innervated bowel (with or without the initial deviation). (Lee, 2009)
Pathophysiology
Hirschsprung disease caused by the failure kranio-caudal migration of the embryo ganglion cells along the intestine at week 5 to week 12., Which is leading to a large segment of aganglionik. In this segment, which coordinated peristalsis propulsif will be lost and the internal anal sphincter fails to loosen during rectal distension. This gives rise to obstruction, abdominal distension and constipation. Aganglionik distal segment remains narrow and had dilated proximal segment ganglionik. This can be seen on barium enema as a transition zone. (Fardah, 2006)
Congenital aganglionosis of the distal colon defines Hirschsprung disease. Aganglionosis begins with the anus, which is always involved, and continues proximally for variable distances. Both the myenteric (Auerbach) and submucosal plexus (Meissner) plexus are absent, so the reduced bowel peristalsis and function. The exact mechanism underlying the development of Hirschsprung's disease is unknown.
enteric ganglion cells derived from the peak of the nerve. In normal development, neuroblasts will be found in the small intestine in the 7th week of pregnancy and will reach the large intestine at 12 weeks' gestation. One possible etiology for Hirschsprung disease is a defect in this migration of neuroblasts along the path to their distal colon. Or, normal migration can occur with failure of neuroblasts to survive, proliferate, or differentiate in the distal segment aganglionik. abnormal distribution in the affected bowel components required for neuronal growth and development, such as fibronektin, laminin, neural cell adhesion molecule (NCAM), and neurotrophic factors, may be responsible for this theory. In addition, the observation that smooth muscle cells of intestine aganglionik is electrically inactive when undergoing electrophysiologic studies also showed myogenic component in the development of Hirschsprung disease.Akhirnya, abnormalities in interstitial cells, enteric nerve cells connecting the pacemaker and the small intestine muscle, also been postulated as a factor. Three important contributions plexus nerves innervate the gut: the submucosal (ie, Meissner) plexus, (ie, Auerbach) intermuscular plexus, and mucosal plexus smaller. All the delicate plexus integrated and involved in all aspects of bowel function, including absorption, secretion, motility, and blood flow (Lee, 2009).
Normal motility, especially under the control of intrinsic neurons. adequate bowel function, although the loss of extrinsic innervation. These ganglia control smooth muscle contraction and relaxation, with relaxation dominates. Extrinsic control mainly through cholinergic and adrenergic fibers. Cholinergic fibers causes contraction, and cause inhibition of adrenergic fibers in particular.
In patients with Hirschsprung's disease, ganglion cells were absent, leading to a marked increase in extrinsic intestinal innervation. The innervation of the cholinergic system and the adrenergic system is 2-3 times of normal innervation. System (excitatory) adrenergic system is expected to dominate over (inhibitors), cholinergic, causes an increase in smooth muscle tone. With the loss of intrinsic enteric inhibitory nerves, which increases tone protected and cause imbalance of smooth muscle contractility, peristalsis is not coordinated, and functional obstruction. (Lee, 2009)
In Hirschsprung's disease, certain nerve cells (ganglion cells) in most of the large intestine is missing. Therefore, the muscles in that area can not be relaxation, muscle contractions that normally push food and digestive waste through the section of the colon can not occur. The figure below shows the large intestine rectum where the lack of nerve ganglion cells, causing swelling in the area above it. (Sexton, 2010)
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