Hirschsprung's disease in children
Introduction
Introduction to pediatric congenital megacolon Congenital megacolon (Hirschsprung's disease) is due to the continuous bowel in the distal rectum or colon, and the stool stagnates in the proximal colon, so that the intestines are dilated and hypertrophied, which is a common digestive tract malformation in children. The incidence of this disease in foreign countries is seen in every 5,000 people, and domestic statistics account for the second place in the digestive tract malformation. About 90% of the patients are boys, and the first visit is mostly in the neonatal period. basic knowledge The proportion of illness: 0.24% Susceptible people: good for children Mode of infection: non-infectious Complications: constipation shock
Cause
Causes of congenital megacolon in children
(1) Causes of the disease
The etiology of this disease is still unclear. Most scholars believe that it is closely related to heredity. The pathogenesis of this disease is the absence of distal intestinal ganglion cells, or abnormal function, so that the intestine is in a state of stenosis, and the intestines are not smooth. The proximal intestinal tube is compensatory and the wall is thickened. This disease can sometimes be combined with other malformations.
(two) pathogenesis
The lesions occur at the junction of the sigmoid colon and the rectum. The distance from the rectum to the proximal end of the intestine without ganglion cells varies, and can be long. Individual cases can affect the entire colon. In rare cases, it is very short. The intestine segment without ganglion cells can be normal under the naked eye or X-ray. Therefore, it is necessary to confirm the presence or absence of ganglion cells, which depends on the rectal biopsy. Because the intestinal tube of the lesion has a lack of normal peristalsis, it is often in a paralyzed state and forms a functional. Intestinal obstruction, the difficulty in the passage of feces, because the feces can not smoothly enter the rectum, the ampulla is often empty, can not stimulate the receptors of the rectal wall to cause normal bowel reflex, therefore, the proximal end of the calf tube due to long-term deposition of a large amount of feces and gas, The intestinal wall is gradually thickened, the intestinal lumen is dilated, and the megacolon is formed. Therefore, the main lesion of the disease is the distal segment of the intestine, and the huge colon is merely the consequence of functional intestinal obstruction.
The visual anatomy of the megacolon and clinical symptoms depend on the lack of ganglion intestine and the age of the patient. In the neonatal period, all the colon and even the small intestine are extremely dilated due to the intestinal tract of the lesion, and the intestinal wall becomes thin. The disease course is shorter, there is no typical intestinal wall hypertrophy change of megacolon, and even intestinal perforation can occur. It occurs mostly in the cecum or sigmoid colon, that is, the proximal end of the stenosis of the intestine. The older the colon, the more obvious the expansion and hypertrophy of the colon. It tends to be limited. Recently, Howard et al studied the distribution of autonomic nerves on the intestine of 19 cases of megacolon disease. It was found that there are many more cholinergic nerve fibers in the intestine without ganglion cells. The authors believe that increased cholinergic energy The nerve is related to the paralysis state of the distal intestine.
Prevention
Pediatric congenital megacolon prevention
The diagnosis and treatment of congenital megacolon has made great progress in recent years. If children can get early diagnosis and early surgical treatment, the long-term long-term effect is satisfactory, but high. Some children have more stools or incontinence after surgery. It takes a long time to perform defecation training.
Complication
Pediatric congenital megacolon complications Complications constipation shock
1. Chronic constipation.
2. Acute enterocolitis.
3. Bowel perforation.
4. Water, electrolyte metabolism disorders.
5. Secondary infection, shock and even death.
Symptom
Congenital megacolon symptoms in children Common symptoms Loss of appetite, loss of appetite, bloating, diarrhea, edema, intractable constipation, constipation, peritonitis
First, medical history and signs:
More than 90% of children have no fetus within 36 to 48 hours after birth, and then have intractable constipation and bloating. They must go through enema, take laxatives or anal suppository to have a history of defecation, often have malnutrition, anemia and loss of appetite, abdomen Highly inflated and visible wide in the intestine type, rectal examination and diagnosis of the rectum ampulla can not touch the feces, beyond the sputum to the expansion section to touch the stool.
Second, clinical manifestations:
1, delay in the discharge of fetal feces, refractory constipation, bloating, children with different clinical manifestations due to different length of intestinal tube, the longer the sputum, the sooner the constipation symptoms become more serious, more than 48 hours after birth, no feces are discharged or only discharged A small amount of feces can occur in 2 to 3 days in the low part or even complete intestinal obstruction symptoms, vomiting and bloating is not defecation, the sputum is not too long, after a digital rectal examination or warm saline enema can discharge a large amount of meconium and gas and relieve symptoms If the sputum is not too long, the symptoms of obstruction are not easy to relieve. Sometimes emergency surgery is needed. Constipation and bloating are still relieved after the symptoms of intestinal obstruction are relieved. The anus enema should be often used for defecation. In severe cases, it will develop into non-enema without defecation and bloating. Gradually increased.
2, malnutrition stunting long-term abdominal distension constipation, can reduce the appetite of children, affecting the absorption of nutrients, fecal deposition makes the colon hypertrophy, the abdomen can appear wide intestine type, sometimes can touch the feces and feces filled with feces, rectum Finger test: a large amount of gas and loose stools are discharged with the fingers.
3, megacolon associated with enterocolitis is the most common and most serious complications, especially in the neonatal period, the cause is not clear, it is generally believed that long-term obstruction a few days ago, proximal colon secondary hypertrophy, intestinal wall Poor circulation is the basic reason. On this basis, some children have abnormal immune function or allergic allergic constitution and have developed enterocolitis. Some people think that it is caused by bacterial and viral infections, but there is no pathogen growth in stool culture. Colon is the main affected part, mucosal edema, ulcer, localized necrosis, inflammation can invade the muscular layer and can show serosal congestion and edema thickening in the peritoneal cavity, forming exudative peritonitis, the child's whole body question suddenly deteriorates, abdominal distension is serious, Vomiting sometimes diarrhea, due to diarrhea and enlargement of a large amount of intestinal fluid accumulation in the intestine, resulting in dehydration acidosis, high fever, rapid fat, blood pressure, if not treated in time, can cause higher mortality.
Examine
Examination of congenital megacolon in children
1. Biopsy examination took a small piece of tissue from the submucosal layer of the rectal wall and the muscular layer more than 4 cm from the anus. The pathology confirmed the absence of ganglion cells.
2. X-ray findings of the abdominal position flat film showed low colonic obstruction. The typical lateral and anterior and posterior position of the barium enema showed a typical sacral segment and dilated bowel. The sputum function was poor, and there was still sputum after 24 hours. Retention of the agent, if not timely enema to wash out the tincture, can form vermiculite, combined with intestinal inflammation, the intestinal wall of the intestine is jagged, and the expansion of the intestine in the neonatal period is more than half a month after birth. If the diagnosis cannot be confirmed, the following tests are performed.
3, anorectal manometry: the balloon is placed in the anus of the abdomen abdomen, it can be seen that with the increase of internal pressure, the normal pediatric sphincter begins to relax, while the sphincter of the megacolon is tight, no slack reflex.
4, EMG examination: low breaking, low frequency, irregular, peak disappears.
Diagnosis
Diagnosis and diagnosis of congenital megacolon in children
According to the medical history, clinical manifestations and laboratory data is not difficult to make a diagnosis.
Neonatal: meconium-incarcerated syndrome (no mecondary colic) and small left colon syndrome, these two are clear by barium enema examination, and can be self-limiting transient obstruction, but also caused by other causes Obstruction such as low intestinal atresia, colon atresia, fecal constipation, neonatal peritonitis and other identification.
Larger children: physiological obstruction, which is characterized by feces and feces in the rectum, rectal manometry and finger biopsy can be diagnostic, children should be narrowed with rectal anus, secondary to tumor compression inside and outside the lumen Scromegaly, colonic weakness (such as constipation caused by hypothyroidism), habitual constipation and children with idiopathic megacolon (more sudden after 2 years of age, internal sphincter dysfunction, with comprehensive conservative treatment ) Equal phase identification.
