Fecal immunochemical test

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Fecal immunochemical test
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Faecal Immunochemical Testing

The fecal immunochemical test (FIT) is a diagnostic technique that examines stool samples for traces of non-visible blood, which could potentially indicate conditions including bowel cancer. [1] Symptoms which could be caused by bowel cancer and suggest a FIT include a change in bowel habit, anaemia, unexplained weight loss, and abdominal pain. [2] [3] By using a random forest classification model, sensitivity can be increased. [4]

Note: Blood in stools does not always mean the presence of bowel or anal cancer, it could be from other bowel diseases such as ulcerative colitis, Crohn's disease or even hemorrhoids.

A 2022 UK guideline for patients with signs or symptoms of suspected colorectal cancer recommends the use of a FIT threshold of faecal haemoglobin ≥10 μg Hb/g to select patients with symptoms for an urgent referral for colorectal cancer investigation. [5]

Related Research Articles

<span class="mw-page-title-main">Ulcerative colitis</span> Inflammatory bowel disease that causes ulcers in the colon

Ulcerative colitis (UC) is one of the two types of inflammatory bowel disease (IBD), with the other type being Crohn's disease. It is a long-term condition that results in inflammation and ulcers of the colon and rectum. The primary symptoms of active disease are abdominal pain and diarrhea mixed with blood (hematochezia). Weight loss, fever, and anemia may also occur. Often, symptoms come on slowly and can range from mild to severe. Symptoms typically occur intermittently with periods of no symptoms between flares. Complications may include abnormal dilation of the colon (megacolon), inflammation of the eye, joints, or liver, and colon cancer.

<span class="mw-page-title-main">Constipation</span> Infrequent or difficult bowel movements

Constipation is a bowel dysfunction that makes bowel movements infrequent or hard to pass. The stool is often hard and dry. Other symptoms may include abdominal pain, bloating, and feeling as if one has not completely passed the bowel movement. Complications from constipation may include hemorrhoids, anal fissure or fecal impaction. The normal frequency of bowel movements in adults is between three per day and three per week. Babies often have three to four bowel movements per day while young children typically have two to three per day.

<span class="mw-page-title-main">Fecal incontinence</span> Inability to refrain from defecation

Fecal incontinence (FI), or in some forms, encopresis, is a lack of control over defecation, leading to involuntary loss of bowel contents — including flatus (gas), liquid stool elements and mucus, or solid feces. FI is a sign or a symptom, not a diagnosis. Incontinence can result from different causes and might occur with either constipation or diarrhea. Continence is maintained by several interrelated factors, including the anal sampling mechanism, and incontinence usually results from a deficiency of multiple mechanisms. The most common causes are thought to be immediate or delayed damage from childbirth, complications from prior anorectal surgery, altered bowel habits. An estimated 2.2% of community-dwelling adults are affected. However, reported prevalence figures vary. A prevalence of 8.39% among non-institutionalized U.S adults between 2005 and 2010 has been reported, and among institutionalized elders figures come close to 50%.

<span class="mw-page-title-main">Colorectal cancer</span> Cancer of the colon or rectum

Colorectal cancer (CRC), also known as bowel cancer, colon cancer, or rectal cancer, is the development of cancer from the colon or rectum. Signs and symptoms may include blood in the stool, a change in bowel movements, weight loss, abdominal pain and fatigue. Most colorectal cancers are due to lifestyle factors and genetic disorders. Risk factors include diet, obesity, smoking, and lack of physical activity. Dietary factors that increase the risk include red meat, processed meat, and alcohol. Another risk factor is inflammatory bowel disease, which includes Crohn's disease and ulcerative colitis. Some of the inherited genetic disorders that can cause colorectal cancer include familial adenomatous polyposis and hereditary non-polyposis colon cancer; however, these represent less than 5% of cases. It typically starts as a benign tumor, often in the form of a polyp, which over time becomes cancerous.

<span class="mw-page-title-main">Colonoscopy</span> Examination of the bowel

Colonoscopy or coloscopy is a medical procedure involving the endoscopic examination of the large bowel (colon) and the distal portion of the small bowel. This examination is performed using either a CCD camera or a fiber optic camera, which is mounted on a flexible tube and passed through the anus.

<span class="mw-page-title-main">Rectal examination</span> Medical assessment or diagnostic procedure

Digital rectal examination (DRE), also known as a prostate exam, is an internal examination of the rectum performed by a healthcare provider.

<span class="mw-page-title-main">Inflammatory bowel disease</span> Medical condition

Inflammatory bowel disease (IBD) is a group of inflammatory conditions of the colon and small intestine, with Crohn's disease and ulcerative colitis (UC) being the principal types. Crohn's disease affects the small intestine and large intestine, as well as the mouth, esophagus, stomach and the anus, whereas UC primarily affects the colon and the rectum.

<span class="mw-page-title-main">Fecal occult blood</span> Blood in the feces that is not visibly apparent

Fecal occult blood (FOB) refers to blood in the feces that is not visibly apparent. A fecal occult blood test (FOBT) checks for hidden (occult) blood in the stool (feces).

<span class="mw-page-title-main">Stool test</span> Medical examination of fecal matter

A stool test is a medical diagnostic technique that involves the collection and analysis of fecal matter. Microbial analysis (culturing), microscopy and chemical tests are among the tests performed on stool samples.

<span class="mw-page-title-main">Fecal impaction</span> Solid buildup of feces in the rectum due to chronic constipation

A fecal impaction or an impacted bowel is a solid, immobile bulk of feces that can develop in the rectum as a result of chronic constipation. Fecal impaction is a common result of neurogenic bowel dysfunction and causes immense discomfort and pain. Its treatment includes laxatives, enemas, and pulsed irrigation evacuation (PIE) as well as digital removal. It is not a condition that resolves without direct treatment.

<span class="mw-page-title-main">Blood in stool</span> Medical condition of blood in the feces

Blood in stool looks different depending on how early it enters the digestive tract—and thus how much digestive action it has been exposed to—and how much there is. The term can refer either to melena, with a black appearance, typically originating from upper gastrointestinal bleeding; or to hematochezia, with a red color, typically originating from lower gastrointestinal bleeding. Evaluation of the blood found in stool depends on its characteristics, in terms of color, quantity and other features, which can point to its source, however, more serious conditions can present with a mixed picture, or with the form of bleeding that is found in another section of the tract. The term "blood in stool" is usually only used to describe visible blood, and not fecal occult blood, which is found only after physical examination and chemical laboratory testing.

Rectal bleeding refers to bleeding in the rectum, thus a form of lower gastrointestinal bleeding. There are many causes of rectal hemorrhage, including inflamed hemorrhoids, rectal varices, proctitis, stercoral ulcers, and infections. Diagnosis is usually made by proctoscopy, which is an endoscopic test.

The Bristol stool scale is a diagnostic medical tool designed to classify the form of human faeces into seven categories. It is used in both clinical and experimental fields.

<span class="mw-page-title-main">Fecal microbiota transplant</span> Process of transplantation of fecal bacteria from a healthy individual into a recipient

Fecal microbiota transplant (FMT), also known as a stool transplant, is the process of transferring fecal bacteria and other microbes from a healthy individual into another individual. FMT is an effective treatment for Clostridioides difficile infection (CDI). For recurrent CDI, FMT is more effective than vancomycin alone, and may improve the outcome after the first index infection.

<span class="mw-page-title-main">Stool guaiac test</span> Test for the presence for occult blood

The stool guaiac test or guaiac fecal occult blood test (gFOBT) is one of several methods that detects the presence of fecal occult blood. The test involves placing a fecal sample on guaiac paper and applying hydrogen peroxide which, in the presence of blood, yields a blue reaction product within seconds.

Faecal calprotectin is a biochemical measurement of the protein calprotectin in the stool. Elevated faecal calprotectin indicates the migration of neutrophils to the intestinal mucosa, which occurs during intestinal inflammation, including inflammation caused by inflammatory bowel disease. Under a specific clinical scenario, the test may eliminate the need for invasive colonoscopy or radio-labelled white cell scanning.

<span class="mw-page-title-main">Cancer screening</span> Method to detect cancer

The objective of cancer screening is to detect cancer before symptoms appear, involving various methods such as blood tests, urine tests, DNA tests, and medical imaging. The purpose of screening is early cancer detection, to make the cancer easier to treat and extending life expectancy. In 2019, cancer was the second leading cause of death globally; more recent data is pending due to the COVID-19 pandemic.

Rectal discharge is intermittent or continuous expression of liquid from the anus. Normal rectal mucus is needed for proper excretion of waste. Otherwise, this is closely related to types of fecal incontinence but the term rectal discharge does not necessarily imply degrees of incontinence. Types of fecal incontinence that produce a liquid leakage could be thought of as a type of rectal discharge.

A rectovaginal examination is a type of gynecological examination used to supplement a pelvic examination. In the rectovaginal examination, a doctor or other health care provider places one finger in the vagina and another in the rectum to assess the rectovaginal septum. The examiner will look for any scarring or masses that may indicate cancer or another disease. Typically, a rectovaginal examination is performed to assess pelvic pain, rectal symptoms, or a pelvic mass. It can also provide a sample for fecal occult blood testing, but is controversial for this purpose.

<span class="mw-page-title-main">Neurogenic bowel dysfunction</span> Human disease involving inability to control defecation

Neurogenic bowel dysfunction (NBD) is the inability to control defecation due to a deterioration of or injury to the nervous system, resulting in faecal incontinence or constipation. It is common in people with spinal cord injury (SCI), multiple sclerosis (MS) or spina bifida.

References

  1. "Bowel Cancer: Testing for blood in your poo using the FIT test". Cancer Research UK. 6 December 2021.
  2. Quintero, Enrique; Castells, Antoni; Bujanda, Luis; et al. (23 February 2012). "Colonoscopy versus Fecal Immunochemical Testing in Colorectal-Cancer Screening". New England Journal of Medicine. 366 (8). Massachusetts Medical Society: 697–706. doi: 10.1056/nejmoa1108895 . hdl: 10486/663879 . ISSN   0028-4793. PMID   22356323.
  3. "Fecal immunochemical test (FIT): MedlinePlus Medical Encyclopedia". medlineplus.gov.
  4. Baxter, Nielson T.; Ruffin, Mack T.; Rogers, Mary A. M.; Schloss, Patrick D. (December 2016). "Microbiota-based model improves the sensitivity of fecal immunochemical test for detecting colonic lesions". Genome Medicine. 8 (1): 37. doi: 10.1186/s13073-016-0290-3 . hdl: 2027.42/134551 . PMC   4823848 . PMID   27056827.
  5. Monahan, Kevin J; Davies, Michael M; Abulafi, Muti; et al. (12 July 2022). "Faecal immunochemical testing (FIT) in patients with signs or symptoms of suspected colorectal cancer (CRC): a joint guideline from the Association of Coloproctology of Great Britain and Ireland (ACPGBI) and the British Society of Gastroenterology (BSG)". Gut. 71 (10): 1939–1962. doi: 10.1136/gutjnl-2022-327985 . hdl: 10044/1/100510 . ISSN   0017-5749. PMC   9484376 . PMID   35820780.