This condition is commonly asymptomatic, and usually only apparent through a systemic inflammatory response. Occlusive ischemia
Mostly the result of a thromboembolism. Commonly the embolism is caused by atrial fibrillation, valvular disease, myocardial infarction, or cardiomyopathy.In addition, ischemic colitis is a well-recognized complication of abdominal aortic aneurysm repair, when the origin of the inferior mesenteric artery is covered by the aortic graft. In a 1991 review concerning 2137 patients the accidental inferior mesenteric artery ligation was the most common cause (74%) of ischemic colitis. Thus, patients without adequate collateralization are at risk for ischemia of the descending and sigmoid colon. Bloody diarrhea and leukocytosis in the postoperative period are essentially diagnostic of ischemic colitis. The complication can be prevented through careful selection of subjects that may require replanting inferior mesenteric artery (IMA) and completing the pre surgical procedure information with an instrumental evaluation during surgical treatment. Pathophysiology
Colonic blood supply
The colon receives blood from both the superior and inferior mesenteric arteries. The blood supply from these two major arteries overlaps, with abundant collateral circulation via the marginal artery of the colon. However, there are weak points, or "watershed" areas, at the borders of the territory supplied by each of these arteries, such as the splenic flexure and the rectosigmoid junction. These watershed areas are most vulnerable to ischemia when blood flow decreases, as they have the fewest vascular collaterals.The rectum receives blood from both the inferior mesenteric artery and the internal iliac artery; the rectum is rarely involved by colonic ischemia due to this dual blood supply.
Gallbladder and sphincter of Oddi disorders

E1. Biliary pain
E1a. Functional gallbladder disorder
E1b. Functional biliary sphincter of Oddi disorder
E2. Functional pancreatic sphincter of Oddi disorderF. Anorectal disorders

F1. Fecal incontinence
F2. Functional anorectal pain
F2a. Levator ani syndrome
F2b. Unspecified functional anorectal pain
F2c. Proctalgia fugax
F3. Functional defecation disorders
F3a. Inadequate defecatory propulsion
F3b. Dyssynergic defecationG. Childhood functional GI disorders: Neonate/Toddler

G1. Infant regurgitation
G2. Rumination syndrome
G3. Cyclic vomiting syndrome (CVS)
G4. Infant colic
G5. Functional diarrhea
G6. Infant dyschezia
G7. Functional constipationH. Childhood functional GI disorders: Child/Adolescent

H1. Functional nausea and vomiting disorders
H1a. Cyclic vomiting syndrome (CVS)
H1b. Functional nausea and functional vomiting
H1b1. Functional nausea
H1b2. Functional vomiting
H1c. Rumination syndrome
H1d. Aerophagia
H2. Functional abdominal pain disorders
H2a. Functional dyspepsia
H2a1. Postprandial distress syndrome
H2a2. Epigastric pain syndrome
H2b. Irritable bowel syndrome (IBS)
H2c. Abdominal migraine
H2d. Functional abdominal pain ‒ NOS
H3. Functional defecation disorders
H3a. Functional constipation
H3b. Nonretentive fecal incontinence

Epidemiology
Functional gastrointestinal disorders are very common. Globally, irritable bowel syndrome and functional dyspepsia alone may affect 16–26% of the population. Research
There is considerable research into the causes, diagnosis and treatments for FGIDs. Diet, microbiome, genetics, neuromuscular function and immunological response all interact. A role for mast cell activation has been proposed as one of the factors. See also
Allergy
Food intolerance
Functional indigestion
Histamine intolerance

References


== External links ==