Enterocolitis, antibiotic-associated

The answer is c. (Hardman, pp 996-997r 1145—1146. Ka tzung, p 8455 Metronidazole is often used to treat antibiotic-associated enterocolitis, especially when caused by C difficile. Vancomycin is no longer preferred because it induces selection of resistant staphylococci. Clindamycin is also associated with C difficile colitis, but in another way a higher percentage of patients taking this over other antibiotics develop antibiotic-associated enterocolitis. 

Oral Staphylococcal enterocolitis and antibiotic-associated pseudomembranous colitis produced by C. difficile. The parenteral product may also be given orally for these infections. Oral vancomycin is not effective for other types of infection. 

The spectrum of gastrointestinal tract infections (GTI) cover a wide spectrum from asymptomatic Helicobacter pylori gastritis to self-limiting viral gastroenteritis to food poisoning to bacterial enterocolitis to antibiotic-associated Clostridium difficile colitis to typhoid fever with sepsis and multi-organ failure. 

Vancomycin is poorly absorbed from the intestinal tract and is administered orally only for the treatment of antibiotic-associated enterocolitis caused by C difficile. Parenteral doses must be administered intravenously. A 1-hour intravenous infusion of 1 g produces blood levels of 15-30 mcg/mL for 1-2 hours. The drug is widely distributed in the body. Cerebrospinal fluid levels 7-30% of simultaneous serum concentrations are achieved if there is meningeal... 

Oral vancomycin, 0.125-0.25 g every 6 hours, is used to treat antibiotic-associated enterocolitis caused by C difficile. Because of the emergence of vancomycin-resistant enterococci and the selective pressure of oral vancomycin for these resistant organisms, metronidazole had been preferred as initial therapy over the last two decades. However, recent clinical data suggest that vancomycin is associated with a better clinical response than metronidazole for more severe cases of C difficile enterocolitis. Therefore, oral vancomycin may be used as a first line treatment for severe cases or for cases that fail to respond to metronidazole. 

Common adverse effects are diarrhea, nausea, and skin rashes. Impaired liver function (with or without jaundice) and neutropenia sometimes occur. Severe diarrhea and enterocolitis have followed clindamycin administration. Antibiotic-associated colitis that has followed administration of clindamycin and other drugs is caused by toxigenic C difficile. This potentially fatal complication must be recognized promptly and treated with metronidazole, 500 mg orally or intravenously three times a day (the preferred therapy), or vancomycin, 125 mg orally four times a day (less desirable given the increasing prevalence of vancomycin-resistant enterococci). Relapse may occur. 

Metronidazole is indicated for treatment of anaerobic or mixed intra-abdominal infections, vaginitis (trichomonas, bacterial vaginosis), antibiotic-associated enterocolitis, and brain abscess. The typical dosage is 500 mg three times daily orally or intravenously (30 mg/kg/d). Vaginitis may respond to a single 2 g dose. A vaginal gel is available for topical use. 

Vancomycin is an antibiotic used to treat Staphylococcus and Clostridium difficile.These bacteria infect bones and joints and cause endocarditis and enterocolitis. Vancomycin is commonly prescribed to patients who are susceptible to endocarditis to prevent this infection from occurring. Vancomycin is particularly successful in treating methicillin-resistant strains of bacteria. However, parenteral vancomycin is not used to treat antibiotic-associated pseudomembranous colitis. 

Hurley BW, Nguyen CC. The spectrum of pseudomembranous enterocolitis and antibiotic-associated diarrhea. Arch Intern Med 2002 162 2177-2184. 

Vancomycin (500 mg IV q. 6 hours) is indicated for the treatment of severe staphylococcal infections, when other antibiotics are ineffective or contraindicated. Vancomycin (125 to 500 mg p.o. q. 6 hours for 7 to 10 days) is indicated for the treatment of antibiotic-associated pseudomembranous and staphylococcal enterocolitis and vancomycin (1 g IV given slowly over 1 hour, starting 1 hour before a procedure) is indicated for endocarditis prophylaxis for dental, Gl, biliary, and genitourinary instrumentation procedures and... 

Vancomycin is also used for the treatment of Clostridium difficile and staphylococcal enterocolitis, which are treated orally or parenterally. However, parenteral vancomycin is not recommended for treating antibiotic-associated pseudomenbranous coMtis. 

Beneficial effects of probiotic consumption in the prevention and treatment of several gastrointestinal diseases, such as inflammatory bowel diseases, antibiotic associated-diarrhoea, neonatal necrotizing enterocolitis, irritahle bowel syndrome, Helicobacter pylori infection, as well as food allergies and intolerances, have been clearly assessed (Sanders et al. 2013). Furthermore, probiotics are effective in reducing cholesterol levels and lowering blood pressure (Kumar et al. 2012). However, molecular mechanisms underlying strain-specific probiotic action and the identity of effector molecules (peptidoglycan, teichoic acid, cell surface polysaccharides, extracellular proteins) still remain to be fully elucidated. 

Diarrhea Diphenoxylate may prolong or aggravate diarrhea associated with organisms that penetrate intestinal mucosa (ie, toxigenic Escherichia coli, Salmonella, Shigella) or in pseudomembranous enterocolitis associated with broad-spectrum antibiotics. Do not use diphenoxylate in these conditions. In some patients with acute ulcerative colitis, diphenoxylate may induce toxic megacolon. Fluid/Electrolyte balance Dehydration, particularly in younger children, may... 

I Contraindications Acute ulcerative colitis (may produce toxic megacolon), diarrhea associated with pseudomembranous enterocolitis due to broad-spectrum antibiotics or to organisms that invade intestinal mucosa (such as Escherichia coli, shigella, and salmonella), patients who must avoid constipation... 

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