Congenital megacolon (Hirschsprung′s discase) is also known as intestinal atelectasis (Agangliono-sis). Since hirschsprung describes it in detail, it is usually called Hirschsprung’s- Disease, which is a common congenital intestinal malformation in children due to persistent spasm of the intestinal canal in the distal rectum or colon and stagnation of feces in the proximal colon, making this intestine hypertrophic and dilated. The disease is characterized by a deficiency of intermuscular nerve cells in the distal part of the affected intestinal segment, which produces spastic contraction, narrowing of the intestinal canal, and loss of peristaltic capacity. The proximal intestinal segment is dilated with secondary compensatory dilated hypertrophy. The incidence is 1 case in 2000-5000 newborns, which is second only to rectoanal malformation and ranks 2nd in neonatal gastrointestinal malformation. Clinical manifestations: 1. Delayed discharge of fetal stool, persistent constipation and abdominal distension. Children have different clinical manifestations depending on the length of the diseased intestinal canal. The longer the spastic segment, the earlier and more severe the constipation symptoms appear. Most of them have no fetal stool or only a small amount of fetal stool within 48 hours after birth, and may develop symptoms of low-level partial or even complete intestinal obstruction, vomiting and abdominal distension without defecation within 2-3 days. If the spastic segment is not too long, a large amount of feces and gas can be excreted after rectal examination or warm saline enema and the symptoms are relieved. If the spastic segment is not too long, the obstructive symptoms are not easily relieved, and sometimes emergency surgery is needed. After the symptoms of intestinal obstruction are relieved, there is still constipation and abdominal distension, and it is necessary to frequently dilate the anus and enema to defecate, and in serious cases, it develops into no enema and no defecation, and the abdominal distension gradually increases. 2, malnutrition and stunted development. Long-term abdominal distension and constipation, can make the child’s appetite decreased, affecting the absorption of nutrients. Stool accumulation makes the colon hypertrophy and expansion, the abdomen can appear wide intestine type, sometimes can be touched full of fecal intestinal collaterals and fecal stones. 3, megacolon with small intestine colitis. It is the most common and serious complication, especially in the neonatal period. Its etiology is not clear, it is generally believed that long-term obstruction in the distant anterior days, secondary hypertrophy and dilatation of the proximal colon, poor circulation of the intestinal wall is the basic cause, on the basis of which some children with abnormal immune function or allergic allergic body reactions and produce small bowel colitis. It is also thought to be caused by bacterial and viral infections, but stool cultures are mostly free of pathogenic bacterial growth. The colon is the main site of involvement, with mucosal edema, ulceration, and limited necrosis. Inflammation invading the muscular layer may show plasma membrane congestion and edema thickening with exudation in the abdominal cavity, forming exudative peritonitis. The child’s generalized fever suddenly worsens, with severe abdominal distension, vomiting and sometimes diarrhea. Due to diarrhea and the accumulation of large amounts of intestinal fluid in the enlarged intestinal canal, it produces dehydration and acidosis with high fever, rapid pulse and decreased blood pressure, which can cause high mortality if not treated in time. The treatment of congenital megacolon includes conservative treatment and surgical treatment. Once diagnosed, radical megacolon surgery is required sooner or later to relieve symptoms. Conservative treatment is suitable for children with mild clinical manifestations, incomplete diagnosis and preparation for surgery, and the main methods are: stimulating the anorectum with soap paste, corkage, etc. If necessary, warm saline enema can be used to cause the child to defecate. Surgical treatment includes transitional surgery (enterostomy) and radical surgery. Enterostomy is generally used for patients with complicated small bowel colitis, intestinal perforation or poor general nutritional status who are unable to tolerate major surgery, and radical surgery is performed after the general condition has improved. Radical surgery involves complete removal of the stenotic intestinal segment at the lesion and restoration of intestinal continuity. Due to improved surgical techniques and supervision, children with congenital megacolon 2-3 months after birth or even earlier can safely undergo radical surgery, thus avoiding complications such as small bowel colitis and malnutrition. In addition, children should be trained to defecate after surgery and have their anus dilated regularly under the guidance of the doctor to consolidate the long-term results.