Radiation enteritis is a condition that arises as a side effect of radiotherapy during the treatment of cancer. It may cause gastrointestinal symptoms such as a change in bowel habits and abdominal pain, which may be acute or chronic.
Radiation enteritis (RE) is an iatrogenic ailment that involves injury to the small intestine, resulting from radiation therapy employed in the treatment of malignancies. RE affects the majority of patients undergoing radiation in the abdomen or pelvis . Factors that predispose patients to RE entail high dose radiotherapy, cardiovascular disease, and those simultaneously receiving chemotherapy.
RE may be acute or chronic in nature. Acute disease may present with abdominal pain, in addition to a variety of nonspecific gastrointestinal (GI) symptoms such as nausea, vomiting, anorexia, and change in bowel habits. These occur and peak with 2 to 5 weeks of initiation of therapy . Acute RE often resolves spontaneously, after 3 months of treatment .
Chronic RE has a much slower onset and may transpire years after exposure to radiotherapy . It occurs due to repeated injury of the gut, leading to inflammation and atrophy of mucosal cells, fibrosis, and impaired healing . The nature and severity of symptoms correspond with the associated damage . Furthermore, radiotherapy affects local blood vessels, causing arterial occlusion by surrounding tissues, that is, endarteritis obliterans, leading to chronic ischemia. Chronic RE manifests as nonspecific GI symptoms, bowel obstruction, fat malabsorption and abdominal pain associated with food intake . Micronutrient deficiencies, such as vitamin B12 and calcium, are also known findings.
Entire Body System
During irradiation, diarrhea occurred in 69% and 66% of the 5-ASA and placebo groups, respectively (chi2, P 0.22). Curves of survival without diarrhea did not differ between groups (logrank P 0.09). [ncbi.nlm.nih.gov]
NOS ( R19.7 ) functional diarrhea ( K59.1 ) infectious gastroenteritis and colitis NOS ( A09 ) neonatal diarrhea (noninfective) ( P78.3 ) psychogenic diarrhea ( F45.8 ) due to radiation K52.0 Enteritis (acute) (diarrheal) (hemorrhagic) (noninfective) [icd10data.com]
Spicy foods trigger diarrhea for many. (Image: Philhillphotography/iStock/Getty Images) Each individual has different types of foods that trigger diarrhea, and for many the offending source is spicy foods. [livestrong.com]
The following suggestions can help you manage chronic diarrhea: If this is a new symptom, tell your doctor about it. [oncologynutrition.org]
If broth is used instead of water, omit the salt. 18) Many RD's use glutamine therapy to help those people with chronic diarrhea that does not resolve with other dietary changes. Use 10 gm three times per day mixed with clear juice or water. [cancerrd.com]
Chronic Abdominal Pain
To increase the diagnostic yield of radiation enteritis, capsule endoscopy was performed in patients having anemia or chronic abdominal pain after chemoradiotherapy. RESULTS: Fifteen patients were enrolled between June 2007 and December 2008. [ncbi.nlm.nih.gov]
RE is a significant problem, as it negatively impacts the quality of life. Furthermore, the condition may not receive adequate attention and treatment due to patients being less forthcoming about GI complaints, as well as clinicians failing to recognize and refer the former to specialists  . It is thus important to educate patients about the possible gastrointestinal side effects of radiotherapy and encourage a preventative health-seeking behavior. In radiation enteritis, the medical history is of significant importance, as it may reveal radiotherapy exposure, possibly many years prior to presentation. Clinical examination further aids in diagnosis.
Biochemically, chronic RE may be evidenced by anemia and malnutrition . Sepsis and raised inflammatory markers may be observed if there is an intestinal obstruction. There may also be a concurrent electrolyte imbalance, abnormal liver function tests, and coagulopathy.
Radiological techniques are useful, as there are a number of changes that are detectable. Computed tomography (CT) and magnetic resonance imaging (MRI) scans may show signs of intestinal wall inflammation such as thickening of the bowel walls, edema, and features of intestinal obstruction. Fistula formation, between the bowel and adjacent pelvic structures, may also be visualized in this way. The small bowel, as inspected via fluoroscopic enteroclysis, may exhibit signs of edema and fibrosis, stenosis and ulcers. There may be segments that appear similar to a stack of coins. Other radiological exams carried out include barium studies. Invasive techniques include endoscopy.
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