congenital duodenal atresia
Introduction
Introduction to congenital duodenal atresia Congenital duodenal atresia (congenitalduodenalatresia) is caused by incomplete bowel insufficiency in the embryonic stage. It is a disease of intestinal dysplasia. The sick child may be accompanied by other developmental malformations, such as chromosome 13 malformation (congenital stupid type, Down syndrome). In 1733, Calder first described the disease, but it was not until the first time in 1916 that the infant with the disease was treated surgically. By 1931, there were only 9 survival records. In 1941, the surgical methods adopted by two experts, Ladd and Gross, were confirmed and used today. basic knowledge The proportion of illness: 0.005% Susceptible people: seen in infants and young children Mode of infection: non-infectious Complications: dehydration, electrolyte imbalance, aspiration pneumonia
Cause
Congenital duodenal atresia
(1) Causes of the disease
The normal intestinal development process is divided into three stages: 1 lumen opening stage, a small intestine has formed in the small intestine at the early stage of the embryo, 2 epithelial cell proliferation stage, epithelial cells proliferate at 5-10 weeks, and the intestinal lumen is occluded. During the temporary filling period, 3 re-cavation stage, the embryo is completed at 11 to 12 weeks, many vacuoles appear in the occlusion intestine, and they fuse with each other to make the lumen communicate again, if the embryonic intestine develops in the second or third month. Obstacles, no vacuoles appear in a certain segment, stay in the parenchyma, or appear vacuoles but do not fuse with each other, or incomplete fusion, will form the infarction or stenosis of the intestine, some people think that intestinal blood circulation disorder during fetal period, hinder the normal development of the small intestine Blocking occurs, such as umbilical ring contraction too fast, the gastrointestinal tube is straight tubular before 8 weeks of embryo, after the intestinal tract is developing rapidly, the abdominal cavity is expanded slowly, causing the small intestine to bend, the abdominal cavity can not accommodate, protrude into the umbilical sac, 10 to 12 weeks of abdominal cavity Increase, the prominent midgut rotates counterclockwise, and is also incorporated into the abdominal cavity, and also shrinks the anterior umbilical ring, affecting the blood circulation of the small intestine, causing atrophy and developing into a narrow Or atresia, vascular abnormalities, such as intestinal nourishment, chipped or branched malformation, or can be caused by intussusception dysplasia.
(two) pathogenesis
1. Predilection site: Congenital duodenal atresia can be located in any part of the duodenum, but it is most common in the common bile duct, pancreatic duct, and ampulla. The lesion is mostly in the second segment of the duodenum. It is generally believed that the lesion at the distal end of the ampulla is more common than the proximal end.
2. Pathological types: There are 4 types of congenital duodenal atresia:
(1) Blind tube type: The proximal end of the duodenum ends in a blind tube with abnormal expansion, the distal end is small and separated from the proximal end, and the intestine loses its continuity.
(2) Suspension type: The duodenum is blindly closed at the proximal and distal ends, and there is a fiber cord between the two. This type is the most rare.
(3) Blind bundle bag type: Although the proximal and distal ends of the duodenum are connected, a blind bundle is formed in the middle, the intestinal lumen is unobstructed, and the diameters of the proximal end and the distal end are greatly different.
(4) Diaphragm type: This type is most common, accounting for 85% to 90% of duodenal atresia. It is characterized by continuity of the intestine, but there is a septum in the lumen of the second or third segment. Braided, can be a single diaphragm, or multiple diaphragms, most of which are located near the fat nipple, causing different degrees of duodenal obstruction, a small hole in the center or edge of the diaphragm, the diameter of the probe is small, the food is difficult to pass, The non-porous septum is obstructed after birth, and the large septum can be asymptomatic or mild. Kireg (1937) has collected 21 cases of duodenal congenital diaphragm, and 18 of them have diaphragm holes. No, the statistics of the relationship between size and onset time, indicating that the larger the pores of the diaphragm, the later the symptoms appear, some of the symptoms appear in childhood or adulthood, although the anatomy is incomplete occlusion, but in terms of function In fact, it is equivalent to atresia; sometimes the diaphragm is complete, and it is also anatomically blocked. In some cases, the diaphragm can be prolapsed into the third segment.
3. Pathological changes: Closed type of person causes complete obstruction, duodenum and gastric dilatation in the proximal end of obstruction, which may be several times thicker than normal diameter, hypertrophy of intestinal wall, loss of creep motility; duodenal wilt of distal obstruction The sputum is small, there is no gas in the cavity of the complete occlusion case, it is thinner than the chopsticks, and its wall is very thin. If it is a porous diaphragm type, it will cause incomplete obstruction, its obstruction proximal intestinal tube hypertrophy, degree of dilatation and intestinal stenosis. The extent and duration of the disease are related.
Prevention
Congenital duodenal atresia prevention
Pregnant women with excessive amniotic fluid should be alert to the possibility of congenital malformation, amniocentesis and amniotic fluid alpha-fetoprotein, acetylcholinesterase increased at the same time to help prenatal diagnosis.
Complication
Congenital duodenal atresia Complications dehydration electrolyte disorder aspiration pneumonia
Due to persistent vomiting, children may develop dehydration, electrolyte imbalance, and often secondary aspiration pneumonia.
Symptom
Congenital duodenal atresia symptoms Common symptoms Abdominal intestines atresia, weight loss, intestinal perforation, polyhydramnios
1. Premature mother's amniotic fluid: 40 to 60% of mothers with 12-finger atresia have a history of polyhydramnios. Under normal circumstances, amniotic fluid is absorbed by the fetus and absorbed at the distal end of the small intestine. Any obstruction of the intestine is It can cause abnormal accumulation of amniotic fluid. The farther the obstruction is, the less chance there is to have too much amniotic fluid, because there is enough gastrointestinal tract to absorb amniotic fluid and excrete it from the kidneys.
2. Neonatal vomiting: Duodenal atresia occurs shortly after birth (hours to 2 days), and vomiting is frequent, the amount is large, powerful, and sometimes jetting, because the obstruction is mostly in the ampulla of the common bile duct The distal end, so vomit in addition to stomach contents and milk, often mixed with bile, vomiting can be mixed with blood or coffee-like substances, the frequency and extent of vomiting progressively increased.
3. Abnormal bowel movements: due to complete obstruction, children without meconium discharge, occasionally a small number of cases can have 1 or 2 small meconium, the case of the distal part of the duodenum, meconium is only intestinal secretion The composition is mixed with the exfoliated cells, or a small amount of grayish white stool is discharged. The meconium is dryr than normal, the amount is small, the color is light, and the discharge time is later.
4. Bloating: Newborn duodenal obstruction is not significant, most of them only have a slight swelling in the center of the upper abdomen. The baby vomits and decompresses the stomach, so sometimes there is no bloating at all, and the gastric peristalsis is a less common symptom. Intestinal perforation, bloating is more obvious, and even the abdominal wall vein is clearly visible.
5. General situation: The general condition is good in the early stage, and the late cases are often thin.
Examine
Examination of congenital duodenal atresia
1. Amniocentesis cytology: When the mother has too much amniotic fluid, or ultrasound examination is highly suspected of high fetal obstruction, it is feasible to perform amniocentesis amniocentesis to determine whether there is a chromosomal abnormality.
2.Farber test: enema with 1% warm saline or 1% hydrogen peroxide solution, no large feces excretion, can exclude meconium constipation and congenital megacolon, fetal fetus examination without lanugo and keratinized epithelium, indicating no meconium Containing amniotic fluid contents, intestinal atresia has been produced during the fetal period, and it can be used for diagnosis.
3. Abdominal X-ray examination: Standing abdominal plain film or iodine angiography duodenal atresia can show that the stomach and duodenum have enlarged gas-liquid plane in the first segment, that is, the typical "double bubble sign", the whole abdomen There is no gas elsewhere.
4.B-ultrasound: In addition to clinical diagnosis, it can also be used for prenatal examination. In particular, linear array real-time ultrasound examination can show two typical liquid areas in the abdomen of the duodenal atresia, suggesting the disease. Diagnosis, reference for correct diagnosis after birth and ready for treatment.
5. Anal finger examination: The possibility of anal atresia is excluded.
Diagnosis
Diagnosis and diagnosis of congenital duodenal atresia
Diagnostic criteria
Intestinal atresia is highly suspected in the following cases.
1. Premature infants, weighing less than 2500g, began to develop persistent vomiting after birth, large amount, sprayed.
2. There is no normal fetus discharge within 24 to 36 hours after birth, and there is progressive abdominal distension.
3. The mother has pregnancy complications or viral infection in the early pregnancy, and amniotic fluid in the late pregnancy.
4. Anal finger examination can rule out the possibility of anal atresia. Farber test has no amniotic fluid content.
5. Abdominal X examination showed that the proximal end of the stomach and duodenum dilated, showing a "double bubble sign", no gas in other parts of the abdomen, can confirm duodenal obstruction.
Differential diagnosis
Congenital duodenal atresia should be identified with the following diseases.
1. pyloric atresia and diaphragm: vomit does not contain bile, abdominal X-ray plain film only see gastric dilatation with fluid level, expectorant examination showed obstruction in the pyloric sinus.
2. Congenital hypertrophic pyloric stenosis: The vomit contains no bile, and the onset of the disease is 2 to 3 weeks after birth. The right upper quadrant can touch the olive-shaped mass. Both the barium meal and the B-mode ultrasound show the pyloric tube stenosis and prolongation.
3. Annular pancreas: This disease also manifests as the second segment of the duodenum obstruction, sometimes combined with duodenal atresia or stenosis, so it is difficult to identify from clinical examination, and needs to be diagnosed by surgery.
4. Congenital intestinal insufficiency: One of the main symptoms of this disease is the second segment of the duodenum. The barium enema examination shows that the location of the cecum is abnormal, and most of it is located in the upper abdomen.
5. Others: There is still a need to distinguish from meconium peritonitis, congenital megacolon, congenital sling compression of the duodenum and intestinal obstruction.
