pseudomembranous colitis

pseudomembranous colitis

[-mem′brənəs]

Etymology: Gk, pseudes + L, membrana, thin skin

a diarrheal disease frequently found in hospitalized patients who have received antibiotics that caused overgrowth of the anaerobic spore-forming toxin Clostridium difficile. Patients have profuse watery diarrhea, fever, and cramping and are found to have exudates of the colon on endoscopy. Diagnosis is made by identifying the offending toxin in the stool of the affected patient. Antidiarrheals are strictly contraindicated because a life-threatening dilation of the bowel called toxic megacolon may result. The bacterium is passed from patient to patient by health care workers who fail to wash their hands adequately. Strict isolation of infected stools is necessary to prevent outbreaks of epidemics. Treatment with oral vancomycin or parenteral metronidazole usually will result in abatement of symptoms within 3 to 5 days. In mild to moderate cases, supportive therapy alone is required.

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colitis

pl. colitides; inflammation of the colon. There are many types of colitis, each having different etiologies. The differential diagnosis involves the clinical history, fecal examinations, proctoscopy, radiological studies such as barium enemas, and sometimes biopsy.

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antibiotic-associated colitis

colitis associated with antimicrobial therapy occurs in humans and animals. It can range from mild nonspecific colitis and diarrhea to severe fulminant pseudomembranous colitis (see below) with profuse watery diarrhea. The inflammation may be caused by a toxin produced by Clostridium difficile, a microorganism that is not normally present in the resident bowel flora. Presumably, the disruption of the normal flora allows the growth of C. difficile. There is developing evidence that, in foals and adult horses, C. difficile can be associated with diarrheal disease that can vary from mild to self-limiting to an acute and fatal enterocolitis. Evidence for this association is the biological plausibility, some evidence that this syndrome can be reproduced experimentally, and the ability to demonstrate the organism or its toxin in the feces of horses with the enterocolitis in comparison with the low prevalence and absence of toxin in the feces of non-diarrheic horses. This syndrome commonly occurs in horses following antimicrobial therapy and/or hospitalization. It is possible that enterotoxin from intestinal C. perfringens may also contribute in horses and the syndrome has been called equine clostridiosis.

ciliate colitis

colitis in primates caused by Troglodytella spp. and characterized by diarrhea.

colitis cystica profunda

dilated, grossly visible colonic glands protrude through the muscularis mucosae into the submucosa; no specific cause attributed; an incidental necropsy finding, especially in pigs.

eosinophilic ulcerative colitis

occurs in humans and dogs, either as a primary disease or as part of an eosinophilic gastroenteritis. Characterized histologically by eosinophilic infiltration of the lamina propria and submucosa. May be caused by hypersensitivity reactions, parasites or foreign body reactions.

granulomatous colitis

see histiocytic ulcerative colitis (below).

histiocytic ulcerative colitis

a chronic, debilitating inflammation of the colon occurring predominantly in young Boxer dogs. Affected dogs have a chronic hemorrhagic diarrhea with tenesmus, and occasionally vomiting, inappetence and weight loss. Colonic mucosa is thickened, friable and ulcerated. Macrophages containing PAS-positive granules are found in the mucosa and submucosa. The cause of this disease is unknown. It is similar, but not identical to, ulcerative colitis, granulomatous colitis and Whipple's disease of humans.

idiopathic colitis

a disease similar to histiocytic ulcerative colitis (above), occurring predominantly in dogs other than Boxers and lacking the PAS-positive granules in histiocytes.

mucous colitis

see irritable colon syndrome.

plasmacytic-lymphocytic colitis

mucosal infiltration by plasmacytes and lymphocytes associated with sign of colitis in dogs. Dietary hypersensitivity is considered an important cause.

pseudomembranous colitis

a severe acute inflammation of the bowel mucosa, with the formation of pseudomembranous plaques. It is most commonly associated with antimicrobial therapy (see antibiotic-associated colitis (above)). Called also pseudomembranous enterocolitis.

psychologically induced colitis

see irritable colon syndrome.

uremic colitis

an outstanding lesion in cattle dying of uremia.

colitis-X

a peracute colitis of horses, sometimes occurring as outbreaks, characterized by a short course of about 24 hours, profuse diarrhea, sometimes with colic and dysentery and profound dehydration. The cause is unknown and the outcome invariably fatal.

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pseudomembranous

pertaining to or emanating from pseudomembrane.

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pseudomembranous colitis

see pseudomembranous colitis.

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pseudomembranous colitis

Antibiotic-associated colitis, necrotizing colitis GI disease An acute illness, with often severe diarrhea that follows antibiotic therapy with ampicillin, clindamycin, metronidazole, etc, which eliminate the Pt's native bacterial flora, resulting in superinfection by Clostridium difficile, causing most cases of PC; the condition may occur in compromised hosts or the elderly, in a background of colonic obstruction, leukemia, major surgery, uremia, spinal injury, colon CA, burns, infections, shock, heavy metal poisoning, hemolytic-uremic syndrome, ischemia, Crohn's disease, shigellosis, necrotizing enterocolitis, Hirschsprung's disease Clinical Sx range from asymptomatic, to mild diarrhea and abdominal pain, to fulminant colitis with fever, ↑ WBC, vomiting, dehydration, perforation, peritonitis, shock