Overview
Radiation enteritis is a medical disease of the intestinal tract caused by radiation therapy.
Common symptoms include abdominal pain, diarrhea, and blood in the stool.
Mostly caused by pelvic, abdominal, retroperitoneal malignant tumor radiation therapy
Generally, drug therapy is the mainstay of treatment
Definition
Radiation enteritis is intestinal damage caused by radiation therapy for pelvic, abdominal, and retroperitoneal malignancies.
Lesions may involve the small intestine, colon, and rectum.
Common symptoms include abdominal pain, diarrhea, blood in the stool, and intestinal stenosis.
Classification
Classification according to site
Small bowel injury: Radiation enteritis that occurs in the small bowel.
Colon injury: Radiation enteritis that occurs in the colon.
Rectal injury: Radiation enteritis that occurs in the rectum.
Causes
Causes
Radiation enteritis is mainly caused by radiation, which acts on the intestines and causes damage to the intestinal mucosa, leading to intestinal inflammation.
The occurrence of radiation enteritis is affected by both the radiation itself and the sensitivity of the body to radiation.
The effect of radiation itself
The higher the radiation dose, the wider the radiation range and the longer the exposure time, the higher the incidence of radiation enteritis and the more serious the condition.
Sensitivity of the body to radiation
The tolerance of different parts of the intestine to radiation is not consistent, 45~60Gy in the small intestine, 45~60Gy in the colon and 55~80Gy in the rectum.
The highest incidence of radiation enteritis is in the terminal ileum.
Different parts of the gastrointestinal tract have their own characteristics resulting in not the same radiation damage. For example, the colorectum is more prone to radiation colitis because of its relatively fixed position compared with the constantly moving small intestine.
Individual differences
Patients vary in age, nutritional status, underlying diseases, and whether or not there are post-surgical adhesions at the radiation site. Even if they receive the same radiation therapy, the incidence and severity of radiation enteritis may vary.
Pathogenesis
Ionizing radiation has strong penetrating power, which can produce ionization and excitation effects on the molecules of body tissues and generate a large number of free radicals, affecting the structure and function of biological membranes, the replication of DNA and the transcription and translation of proteins; affecting the generation of ATP and cellular energy metabolism.
Ionizing radiation can directly damage the mucosal cells of the digestive tract and intestinal wall tissues, and can also affect the small arteries under the mucosa and lead to vasculitis, both of which are jointly involved in the process of the development of radiological gastrointestinal injury.
Symptoms
Main Symptoms
Early manifestations
The earliest occurs within a few hours after the beginning of radiation therapy, but most of them appear in l~2 weeks of radiation therapy.
Common symptoms include loss of appetite, abdominal pain, diarrhea, mucus or bloody stools, and anal swelling.
Frequent diarrhea can cause water and electrolyte disorders and other manifestations. In addition, the destruction of intestinal mucosal barrier function can be secondary to intestinal bacterial infection.
Late stage manifestations
Mostly occurs 6~18 months after radiation therapy.
In the late stage of radiation small bowel inflammation, the main symptoms are malabsorption and vascular occlusion related symptoms. Symptoms include abdominal pain, diarrhea, steatorrhea and emaciation, anemia, and malaise.
Radiation colorectitis is mainly characterized by abdominal pain, diarrhea, blood in the stool, urgency and heaviness, and intestinal obstruction manifestation when the intestinal lumen is narrowed, and rectovaginal fistula, rectovesical fistula, rectovesical fistula, and so on, can be formed in some patients.
Complications
Intestinal perforation
Radiation enteritis due to radiation damage to the intestines, resulting in brittle intestinal walls, inflammatory damage, and intestinal perforation.
Common symptoms include severe abdominal pain (constant knife-like pain in the abdomen), abdominal distension, fever, chills, rapid heart rate, low blood pressure, and shock.
Intestinal obstruction
Radiation enteritis can lead to weakened peristalsis, narrowing of the intestinal lumen, etc. This will affect the passage of intestinal contents and intestinal obstruction will occur.
Common symptoms include cessation of bowel movement, gas evacuation, abdominal pain and bloating.
Rectal bleeding
Radiation enteritis leads to localized inflammation and edema in the rectum, and in severe cases, rectal bleeding may occur.
Common symptoms include blood in the stool, mucus-like blood stool or pus and blood stool, and pain in the stool.
Anemia
Patients with radiation enteritis who experience prolonged blood in the stool can lead to anemia.
Common symptoms include weakness, easy fatigue, dizziness, tinnitus, fainting, and poor concentration.
Consultation
Department of Medicine
Gastroenterology
Patients with tumors in the abdominopelvic region are advised to seek medical attention if they experience abdominal pain, diarrhea, mucus or bloody stools, and anal swelling after receiving radiation therapy.
Preparation for medical treatment
Preparing for your visit: registering, preparing your documents, and frequently asked questions.
Tips for seeking medical treatment
Before visiting the doctor, try to keep a record of symptoms such as abdominal pain and diarrhea in relation to radiation therapy.
Try to record the shape, color, and frequency of stools, and take pictures if necessary for easy viewing during the visit.
Preparation Checklist
Symptom list
Pay particular attention to the time of onset of symptoms and special symptoms.
Is there abdominal pain or diarrhea?
Is there blood in the stool? What color is the stool?
Is there nausea or vomiting?
How long have these symptoms been present?
What are the circumstances under which these symptoms may worsen or resolve?
Medical History Checklist
Any pelvic, abdominal, or retroperitoneal malignancies with radiation therapy?
Checklist
Test results from the last six months, which can be brought with you to the doctor’s office
Laboratory tests: routine blood, fecal routine.
Imaging examination: CT, magnetic resonance imaging, barium enema angiography.
Endoscopy: colonoscopy.
Histopathologic examination.
List of medications used
Medication used in the last 3 months, if available in boxes or packages, carry with you to the doctor’s office
Anti-inflammatory drugs: mesalazine, olsalazine, prednisolone, hydrocortisone, etc.
Antibiotics: metronidazole, ciprofloxacin, etc.
Antidiarrheal drugs: montelukast, loperamide.
Diagnosis
Diagnosis is based on
Medical history
History of pelvic, abdominal, and retroperitoneal malignancy.
History of radiation therapy.
Clinical manifestations
Symptoms
Symptoms such as loss of appetite, abdominal pain, diarrhea, mucus or bloody stools, and anal cramps.
Laboratory Tests
Blood counts
Decreased hemoglobin level in anemia and increased white blood cell count in combination with infection.
Stool routine
Check whether there are red blood cells, white blood cells and occult blood in the patient’s feces, which can clarify whether there is gastrointestinal bleeding or infection.
Imaging
X-ray barium enema, CT, magnetic resonance and other imaging tests can help determine the scope and nature of the lesion, but the performance lacks specificity.
Commonly, the mucosa of the lesion area is rough and irregular, and the intestinal wall is thickened, stiff, and poor peristalsis, and sometimes ulcers and intestinal stenosis can be seen.
It can clarify the situation of intestinal radiation damage, whether there is intestinal wall thickening. It can also assist in determining the primary tumor.
Endoscopy
Colonoscopy or small enteroscopy
The lesion can be visualized directly, and the exact extent of the damage caused by radiation enteritis can be clarified.
Microscopically, the mucosa of the lesion can be seen to be congested and edematous, erosion, ulceration, bleeding and other manifestations, scarring can be seen after the ulceration has healed, and sometimes capillary dilatation, intestinal luminal narrowing, fistula formation, and other signs can be seen.
If necessary, biopsy can be taken under endoscopy to assist in the diagnosis of pathology.
Histopathologic examination
The pathological nature of radiation enteritis can be clarified by taking the lesion tissue of intestinal mucosa for pathologic examination.
Differential diagnosis
Crohn’s disease
Similarities: both Crohn’s disease and radiation enteritis have symptoms such as abdominal pain, diarrhea, mucus or bloody stools, and anal swelling.
Differences:
Crohn’s disease mucosal ulcers enteroscopy for longitudinal fissure ulcers, visible paving-stone-like changes, preferred in the ileocecal part and the small intestine, lesions between the intestinal segments of the mucosa has a normal appearance, the pathological changes of the whole layer of inflammation, fissure ulcers, non-caseous granulomas and so on.
Radiation enteritis mucosal ulcers are peripheral ulcers with small granulomatous lesions and inflammatory edema surrounding the ulcers.
Ulcerative colitis
Similarities: both ulcerative colitis and radiation enteritis have symptoms of abdominal pain, discharge of mucopurulent blood stools, diarrhea, and erosions and ulcers on colonoscopy.
Differences:
Ulcerative colitis without a history of radiation exposure, colonoscopy lesions were distributed in a continuous manner, the intestinal mucosa was diffuse congestion, edema, common erosion, ulceration, inflammatory polyps and other manifestations, when the disease is longer, the intestinal tube is shortened as a lead pipe, and the intestinal folds become shallow or even disappear.
Radiation enteritis patients have a history of radiation therapy, colonoscopy examination of intestinal segments mucosal congestion, edema, granular changes, increased fragility, mucosa easy to bleed on touch.
Treatment
Treatment objective: to relieve the patient’s symptoms and reduce the occurrence of complications.
Treatment principle: drug treatment is usually the mainstay, and surgical treatment is needed when complications such as intestinal obstruction and intestinal perforation occur.
General treatment
Dietary treatment
Take soft food as the mainstay, such as noodles, porridge, milk, etc., and do not eat hard food, such as melon seeds, peanuts and other nuts.
Patients in the acute stage should have a liquid diet or a diet with little residue, such as porridge, soy milk, thin noodles, etc.
Limit the intake of foods rich in fat, fiber and lactose.
Patients with severe diarrhea and malabsorption should pay attention to strengthening nutritional support pending treatment, and parenteral nutritional supplementation can be added if necessary.
Hyperbaric oxygen therapy
Hyperbaric oxygen therapy can reduce tissue damage, accelerate ulcer healing and promote tissue repair.
Drug treatment
Antibiotics
Indications: suitable for patients with bacterial infection.
Common drugs: metronidazole, ciprofloxacin, etc.
Adverse reactions: nausea, loss of appetite, vomiting, dizziness, headache, etc.
Anti-inflammatory drugs
Indications: For patients with severe diarrhea and/or during radiotherapy.
Common drugs: mesalazine, olsalazine, prednisone, hydrocortisone, etc.
Adverse reactions: dizziness, headache, nausea, bloating, edema and other symptoms.
Probiotics
Indications: suitable for patients with diarrhea.
Common drugs: Lactobacillus, Bifidobacterium, Bacillus licheniformis, etc.
Adverse reactions: gastrointestinal flatulence, diarrhea, etc.
Antioxidants
Indications: suitable for patients undergoing radiotherapy body produces a large number of oxygen free radicals.
Common drugs: vitamin A, vitamin C, vitamin E, etc.
Adverse reactions: gastrointestinal flatulence, nausea, etc.
Anti-diarrhea drugs
Indications: patients with diarrhea.
Common drugs: loperamide, montelukast.
Adverse reactions: gastrointestinal flatulence, loss of appetite, etc.
Growth inhibitors
Indications: For patients with diarrhea for whom loperamide treatment is not effective.
Common drugs: Octreotide.
Common adverse reactions: with gastrointestinal flatulence, nausea and vomiting.
Enema drugs
Indications: suitable for patients with blood in the stool.
Common drugs: there are short-chain fatty acids, aluminum sulfate, metronidazole, prednisone and so on.
Common adverse reactions: there are intestinal flora disorders, dizziness and so on.
Surgical treatment
Indications: for patients with complications such as intestinal stenosis, obstruction, intestinal bleeding, or ineffective drug treatment.
Surgical principle: to solve the clinical symptoms as the primary goal, to improve the patient’s prognosis and long-term quality of life.
Contraindications: patients with abnormal function of heart, lungs, kidneys and other important organs; bleeding disorders, etc.
Endoscopic treatment
Endoscopic dilatation or stent implantation is feasible for patients with digestive tract stenosis to improve symptoms.
Patients with gastrointestinal bleeding can be treated with endoscopic hemostasis, commonly used methods include endoscopic spraying of hemostatic drugs, argon ion coagulation therapy (APC) and so on.
Prognosis
Cure
Most cases of radiation enteritis have a good prognosis after timely medical treatment. However, if not treated timely and effectively, intestinal stenosis and fistula formation may occur, which may be life-threatening in severe cases.
Daily
Daily management
Dietary management
Limit fiber intake and control the intake of fruits and vegetables.
Avoid foods such as gluten and milk.
Try not to eat harder foods such as pistachios, peanuts and other nuts.
Take more protein-rich foods such as lean meat, fish and eggs to enhance nutrition.
Life management
Pay attention to bed rest during treatment.
Ensure sufficient sleep time in daily life and stay up late less.
It is recommended to take a walk in daily life to enhance the resistance of the body.
Pay attention to personal hygiene in daily life and develop good hygiene habits.
Psychological adjustment
Patients with radiation enteritis will be irritable, fear and other bad emotions, the patient’s family should strengthen the communication with the patient and encourage the patient to maintain an optimistic mindset.
Follow-up
Regular follow-ups will help the doctor assess the patient’s condition and prevent complications.
The main review items include imaging examination and endoscopy.
Prevention
Control the overall radiotherapy dose and make individualized radiotherapy plan.
Reduce radiation exposure during radiation therapy by means of lap-banding and shielding with lead garments.