Intestinal vascular malformations
Introduction
Introduction to intestinal vascular malformation Vascular malformation of intestines, including arteriovenous malformations, vasodilation, hemangioma, vascular dysplasia, etc., is one of the causes of acute or chronic lower gastrointestinal bleeding, often abnormal blood vessels, but also a systemic disorder Or one of the manifestations of a certain syndrome. basic knowledge Sickness ratio: 0.05% Susceptible people: no specific people Mode of infection: non-infectious Complications: gastrointestinal bleeding
Cause
Causes of intestinal vascular malformation
(1) Causes of the disease
The etiology and pathogenesis of this disease are not fully understood. It occurs in the jejunum, cecum and right colon. Children, young and middle-aged vascular malformations are more common in jejunum, and middle-aged and elderly vascular malformations are more common in the colon, especially in the right colon. The main clinical manifestations of the patient were gastrointestinal bleeding and secondary anemia.
(two) pathogenesis
Congenital arteriovenous malformation, its pathological changes are submucosal arteriovenous communication, venous arterialization, venous wall thickening, dilatation, distortion, and sclerosis, mostly occurring in the rectum and sigmoid colon, often accompanied by cardiovascular disease, peripheral vascular disease and the main Arterial stenosis; acquired nature is secondary to certain diseases, such as portal hypertension intestinal disease, the submucosal wall degeneration of the elderly with chronic constipation, so that the submucosal veins that pass through the muscular wall of the intestinal wall are repeatedly oppressed by muscle contraction. Increased venous pressure, venous dilatation, anterior capillary dysfunction, direct communication between arteries and veins, formation of functional arteriovenous fistula, small intestinal vascular malformation and colonic vascular malformation often occur.
Prevention
Intestinal vascular malformation prevention
If the active hemorrhage can be found during the operation and the intestine is removed, the bleeding can be stopped immediately, but all the intestines must be carefully and comprehensively examined to avoid omission. Even if there is still a report of recurrence of bleeding after the resection of the lesion, it is mostly because the remaining lesions at the time of surgery have not been diagnosed and have not been detected. The recurrence rate of postoperative bleeding in cases of intestinal vascular malformation is 7% to 90%. The recurrence rate of postoperative bleeding is so large that it is related to whether the bleeding location is accurate and whether the lesion is completely removed.
Complication
Intestinal vascular malformation complications Complications, gastrointestinal bleeding
For gastrointestinal bleeding and secondary anemia.
Symptom
Intestinal vascular malformation symptoms common symptoms intestinal bleeding intestinal bleeding
1. The course of vascular disease varies from length to length, and most of them are older, and the elderly can reach several decades.
2. Various ways of bleeding, acute massive bleeding, repeated intermittent bleeding and chronic small amount of bleeding.
3. Most of the bleeding is self-limiting or hemostasis, blood transfusion can be temporarily stopped, and hemoglobin can return to normal.
4. There were no positive symptoms and signs when there was no bleeding.
Examine
Examination of intestinal vascular malformations
Repeated intermittent bleeding and chronic small amount of bleeding, the total number of red blood cells and hemoglobin in the blood decreased; fecal occult blood test was positive.
1. Selective intestinal angiography Selective or highly selective angiography since 1960 is the main means of diagnosis of this disease, the diagnosis rate can reach 75% to 90%, vascular malformation can be divided into 3 types: I Type is arteriovenous anastomosis or submucosal vascular dysplasia; type II is vascular hamartoma; type III is hemorrhagic telangiectasia (if genetic factors, it is called hereditary hemorrhagic telangiectasia, Also known as Osler-Weber-Rendu syndrome), the main signs after angiography are:
(1) An abnormally large number of vascular plexus, which is structurally disordered.
(2) Spider-like expansion and distortion of peripheral blood vessels.
(3) Early development of the arterial phase of the vein, showing a "double track" sign, suggesting that there is a shunt between the arteries and veins.
(4) In the bleeding period, contrast agent overflow can be accumulated in the intestinal lumen.
(5) In the venous phase, the veins in the intestinal wall on the side of the mesenteric edge are dilated and distorted.
2. Endoscopy After 1970, with the development of endoscopy and the improvement of operator technology, endoscopy such as electronic gastroscope, enteroscopy and colonoscopy has become the preferred method for diagnosing vascular malformation. Capsule endoscopy has been carried out in recent years. The positive rate of diagnosis of small intestine vascular malformation can reach more than 90%, but vascular malformation can be divided into:
(1) Localized type (type I): a limited type of vasodilation, clearly demarcated from the surrounding normal mucosa, including regional vasodilation (Ia) and spider-like vasodilation (Ib).
(2) diffuse type (type II): vasodilation is diffuse, wide range, bright red, and blurred with normal mucosa.
(3) Aneurysm-like type (type III): a purple-red or gray-blue mass, slightly raised on the mucosal surface, and clearly defined with the surrounding normal mucosa.
3. Radionuclide imaging with 99mTc-erythrocyte radionuclide scanning is sensitive to the localization diagnosis of active bleeding caused by intestinal vascular malformation, but it can not be qualitatively diagnosed. It can only be used as an auxiliary method for angiography and endoscopic diagnosis.
4. Surgical exploration has a dual role in the diagnosis and treatment of intestinal vascular malformation bleeding. It is proposed that patients with recurrent bleeding below 50 years of age should be operated as soon as possible. Intraoperative endoscopy and/or intraoperative angiography can be used to help find the lesion.
Diagnosis
Diagnosis and differential diagnosis of intestinal vascular malformation
Diagnostic criteria
1. Clinical features.
2. Selective intestinal angiography.
3. Endoscopy.
4. Radionuclide development.
5. Surgical exploration.
Differential diagnosis
Mainly differentiated from other diseases that cause gastrointestinal bleeding.
1. Peptic ulcer This disease is a chronic, periodic attack, often manifested as rhythmic pain, with acid reflux, hernia, more than autumn and winter, spring seizures, barium meal, endoscopy and angiography can be differentiated from vascular malformations .
2. Digestive tract tumors such as gastric cancer, small intestinal lymphoma, colorectal cancer, etc., can also be expressed as gastrointestinal bleeding, the amount of bleeding can be large or small, depending on the location, size, nature of the tumor, but also often loss of appetite, weight loss, Abdominal pain, abdominal distension, etc., X-ray barium meal examination, endoscopy plus biopsy and angiography can confirm the diagnosis, if necessary, laparotomy.
3. Stomach and intestinal polyps can also have only gastrointestinal bleeding without other clinical manifestations. Endoscopic biopsy and histopathological examination and X-ray barium meal examination can be differentiated from vascular malformations.
4. Cirrhosis of esophageal varices, such as vascular malformation, is characterized by acute massive gastrointestinal bleeding. It should be differentiated from gastrointestinal hemorrhage caused by rupture of esophageal varices in cirrhosis. Hepatic cirrhosis has many causes of hepatitis, schistosomiasis, alcoholism, etc. There are coagulation mechanism disorders, jaundice, loss of appetite and liver function damage, laboratory tests may have abnormal liver function, coagulation mechanism disorders, etc., barium meal or gastroscopy can be found in the lower esophagus and / or gastric varices can be Identification of vascular malformations.
5. Acute gastric mucosal lesions There are many incentives before the onset of this disease, such as brain trauma, drug stimulation, various stress states, etc., mostly acute onset, emergency endoscopy can establish a diagnosis, easy to identify with vascular malformations.
6. Other vascular malformation bleeding needs to be differentiated from ulcerative colitis, Crohn's disease, intestinal tuberculosis, etc. According to the clinical manifestations of the above diseases, laboratory examinations, endoscopy, angiography, etc. can generally find clear lesions.
