Ischemic colitis

Definition

Ischemic colitis is an acute or chronic inflammatory disease of the large intestine due to impaired blood supply to its walls. It is manifested by abdominal pain of varying intensity, unstable stools, bleeding, flatulence, nausea, vomiting, and weight loss (in chronic course). In severe cases, body temperature rises, and there are symptoms of general intoxication. For diagnostic purposes, sigmoidoscopy, irrigoscopy, colonoscopy, and angiography of the inferior mesenteric artery are performed. Treatment at the initial stages is conservative, in case of ineffectiveness of this treatment – surgical. 

General information

Ischemic colitis is a segmental disorder of blood circulation in the walls of the large intestine caused by occlusion or narrowing of blood vessels. This leads to inflammation, stricture, and necrosis of the intestinal area. The disease is registered mainly in older people. It occurs equally frequently in men and women and is distributed evenly in all countries and continents. According to various data, about one-third of all large intestine diseases in older patients are caused by impaired blood circulation in its walls. 

Causes

There are many causes of ischemic colitis associated with spasms of blood vessels supplying the large intestine, their occlusion, and a decrease in total blood pressure. Vascular occlusion may occur due to atherosclerosis, embolism or thromboembolism of mesenteric vessels, allergic reactions, trauma, postoperative complications, or systemic vasculitis. Ischemic colitis, as a consequence of reduced blood pressure, is caused by shock, acute allergic reactions, aortic aneurysm dissection, severe anemia, and significant dehydration of the body (blood loss, intestinal infection with profuse diarrhea).

Necrosis or gangrene of the intestinal wall develops most often in vascular occlusion. The area of the lesion depends on the diameter of the vessel, complete or incomplete occlusion of its lumen, duration of occlusion, and the possibility of collateral blood flow. If the vessel lumen is gradually occluded, for example, in atherosclerosis, ischemic colitis may become chronic with the formation of strictures.

The large intestine is one of the most poorly supplied with blood, especially in areas with vascular anastomoses. Its functional activity is accompanied by an even greater decrease in blood flow. Therefore, shock states, heart failure (acute or chronic), blood loss in trauma, surgery, or fluid loss in intestinal infections very quickly lead to the development of ischemia and, as a consequence, ischemic colitis.

Classification

Ischemic colitis can be acute or chronic. Acute colitis develops with infarction of the mucosa, submucosal layer, and the entire intestinal wall. Chronic colitis may be complicated over time by strictures of the large intestine. Clinical proctology also distinguishes the transient form of ischemic colitis (with regression of symptoms and morphological changes), stenosing (with the formation of strictures), gangrenous (with the formation of ulcers, necrosis of all layers of the intestinal wall, frequent complications, and progressive morphological changes without reversal).

Symptoms of ischemic colitis

Pathology develops acutely or subacutely. In general, patients complain of abdominal pain, recurrent intestinal bleeding, and unstable stools. Diarrhea alternates with constipation; a tendency to frequent liquid stools with a large amount of mucus and blood impurities prevails. Palpation of the abdomen reveals pain in the left iliac region near the umbilicus. Finger rectal examination can reveal blood, mucous, and purulent discharge in the rectum. The intensity of one or another symptomatology depends on the form of ischemic colitis and the size of the affected area.

The reversible form of ischemic colitis develops when the period of circulatory disturbance is short, or collaterals are quickly formed. It is characterized by periodic abdominal pain on the left side or near the navel. Sometimes, their intensity and duration are so small that patients ignore them. Pains appear half an hour after eating or physical activity and can disappear independently for several hours. By its nature, the sensations are similar to the pain of angina pectoris or intermittent claudication. After some time, the tenesmus may join, and the patient may have liquid stools with blood and mucus. Blood in the feces is sometimes detected a few days or weeks after the onset of the disease.

With further development of the pathological condition, symptoms may pass independently or increase if ischemic colitis passes into an irreversible form. In the latter case, the patient’s pain increases, and stools become abundant and liquid, with blood, mucus, and a putrid odor. The general condition worsens, hyperthermia, nausea, vomiting, and symptoms of general intoxication may appear.

Diagnosis

The most informative methods of diagnosis of ischemic colitis are instrumental research methods. Sigmoidoscopy helps to suggest a diagnosis but does not give a complete picture. Small hemorrhages in the mucosa are visible in the reversible form of ischemic colitis in the rectum and sigmoid colon. With the necrotic form, you can see ulcers with precise edges and fibrin films on the background of pale mucosa. More diagnostic data can be obtained when performing a biopsy.

Irrigoscopy is one of the most informative diagnostic studies in ischemic colitis. In the case of reversible changes in ischemia sites, defects in the form of finger indentations can be seen. After a short time, they can disappear, so the study should be carried out immediately at the first suspicion of ischemic colitis. Necrotic changes are seen in the form of persistent ulcerative defects. When performing irrigoscopy, strictures can also be diagnosed. Colonoscopy allows us to see morphological changes in the walls of the entire large intestine more clearly and take biopsies from areas with ischemia or strictures of the colon, especially if there is a suspicion of malignant degeneration.

Angiography of the inferior mesenteric artery is performed to determine the cause and level of vascular obstruction. In complications of ischemic colitis, general and biochemical blood tests are performed to assess the patient’s condition. A bacterial culture of feces and blood with the determination of drug sensitivity is performed to correct antibiotic therapy.

Treatment of ischemic colitis

At the first stage of the disease, the main treatment option is conservative therapy. A sparing diet, mild laxatives, drugs that improve blood flow (vasodilators), and blood rheology (antiplatelet agents) are prescribed. In the severe condition of the patient, carry out detoxification therapy, correction of water-electrolyte balance, and sometimes perform a blood transfusion. Parenteral nutrition is of great importance for unloading the intestine. Antibiotic and sulfonamide drugs are prescribed for bacterial complications of ischemic colitis.

Surgical treatment of ischemic colitis is indicated in cases of extensive necrosis, gangrene of the large intestine, perforation, and peritonitis. The affected area of the intestine is removed within healthy tissue, then revised, and postoperative drainage is left in place. Since the age of patients with ischemic colitis is primarily elderly, complications after such operations are pretty frequent. Elective surgery is performed in strictures that block or narrow the intestinal lumen.

All these treatment options are available in more than 700 hospitals worldwide (https://doctor.global/results/diseases/ischemic-colitis). For example, Sigmoidectomy can be performed in these countries for following approximate prices:

Turkey $7.4 K in 25 clinics

China $19.4 K in 6 clinics

Germany $26.6 K in 43 clinics

Israel $32.2 K in 11 clinics

United States $42.9 K in 15 clinics.

Prognosis and prevention

The prognosis of ischemic colitis depends on the form of the disease, its course, and the presence of complications. The prognosis is quite favorable if blood flow resumes and necrosis does not develop. With necrosis, everything depends on the extensiveness of the process, timely diagnosis, and correctly performed surgical intervention. Also, the course of the pathology depends on the age, general condition of the patient, and concomitant diseases.

Since ischemic colitis occurs in most cases as a complication of atherosclerosis, heart failure, and the postoperative period during interventions on the intestine, stomach, and pelvic organs, the basis of prevention is adequate treatment of primary diseases. Proper nutrition and regular preventive medical examinations are also of great importance.