The search for a better treatment for recurrent Clostridium difficile disease: use of high-dose vancomycin combined with Saccharomyces boulardii.

Recurrent Clostridium difficile disease (CDD) is a difficult clinical problem because antibiotic therapy often does not prevent further recurrences. In a previous study, the biotherapeutic agent Saccharomyces boulardii was used in combination with standard antibiotics and was found to be effective in reducing subsequent recurrences of CDD. In an effort to further refine a standard regimen, we tested patients receiving a regimen of a standard antibiotic for 10 days and then added either S. boulardii (1 g/day for 28 days) or placebo. A significant decrease in recurrences was observed only in patients treated with high-dose vancomycin (2 g/day) and S. boulardii (16.7%), compared with those who received high-dose vancomycin and placebo (50%; P=.05). No serious adverse reactions were observed in these patients. Comparison of data from this trial with data from previous studies indicates that recurrent CDD may respond to a short course of high-dose vancomycin or to longer courses of low-dose vancomycin when either is combined with S. boulardii.

Recurrent Clostridium difficile disease: epidemiology and clinical characteristics.

OBJECTIVE: To describe the epidemiology, diagnosis, risk factors, patient impact, and treatment strategies for recurrent Clostridium difficile-associated disease (CDAD). DESIGN: Data were collected as part of a blinded, placebo-controlled clinical trial testing a new combination treatment for recurrent CDAD. Retrospective data regarding prior CDAD episodes were collected from interviews and medical-chart review. Prospective data on the current CDAD episode, risk factors, and recurrence rates were collected during a 2-month follow-up. SETTINGS: National referral study. PARTICIPANTS: Patients with recurrent CDAD. INTERVENTIONS: Treatment with a 10-day course of low-dose (500 mg/d) or high-dose (2 g/d) vancomycin or metronidazole (1 g/d). RESULTS: Recurrent CDAD was found to have a lengthy course involving multiple episodes of diarrhea, abdominal cramping, nausea, and fever. CDAD may recur over several years despite frequent treatment with antibiotics. Recurrence rates were similar regardless of the choice or dose of antibiotic. Recurrent CDAD is not a trivial disease: patients may have multiple episodes (as many as 14), may require hospitalization, and the mean lifetime cost of direct medical care was $10,970 per patient. Fortunately, the disease does not become progressively more severe as the number of episodes increase. Two risk factors predictive for recurrent CDAD were found: increasing age and a decreased quality-of-life score at enrollment. CONCLUSIONS: Recurrent CDAD is a persistent disease that may result in prolonged hospital stays, additional medical costs, and rare serious complications.

Guidelines for the diagnosis and management of Clostridium difficile-associated diarrhea and colitis. American College of Gastroenterology, Practice Parameters Committee.

Guidelines for clinical practice are intended to suggest preferable approaches to particular medical problems as established by interpretation and collation of scientifically valid research, derived from extensive review of published literature. When data are not available that will withstand objective scrutiny, a recommendation may be made based on a consensus of experts. Guidelines are intended to apply to the clinical situation for all physicians without regard to specialty. Guidelines are intended to be flexible, not necessarily indicating the only acceptable approach, and should be distinguished from standards of care that are inflexible and rarely violated. Given the wide range of choices in any health care problem, the physician should select the course best suited to the individual patient and the clinical situation presented. These guidelines are developed under the auspices of the American College of Gastroenterology and its Practice Parameters Committee. These guidelines are also approved by the governing boards of American College of Gastroenterology and Practice Parameters Committee. Expert opinion is solicited from the outset for the document. Guidelines are reviewed in depth by the committee, with participation from experienced clinicians and others in related fields. The final recommendations are based on the data available at the time of the production of the document and may be updated with pertinent scientific developments at a later time. The following guidelines are intended for adults and not for pediatric patients.

Recurrent Clostridium difficile diarrhea: characteristics of and risk factors for patients enrolled in a prospective, randomized, double-blinded trial.

Recurrent Clostridium difficile diarrhea (RCDD) occurs in 20% of patients after they have received standard antibiotic treatment with vancomycin or metronidazole, but the reasons for the recurrences are largely unknown. Patients receiving vancomycin or metronidazole for active C. difficile diarrhea (CDD) were referred to our study centers for treatment and a 2-month follow-up as part of a randomized placebo-controlled trial. Sixty patients had RCDD (median number of episodes, 3.0; range, 2-9 episodes) and 64 were having their first episode of CDD. Patients with RCDD had more-severe abdominal pain and were more likely to have fever but initially responded well to antibiotic therapy. Data on sequential episodes showed no progression in disease severity. Five factors were associated with a higher risk of RCDD: the number of previous CDD episodes, onset of the initial disease in the spring, exposure to additional antibiotics for treatment of other infections, infection with immunoblot type 1 or 2 strains of C. difficile, and female gender. These factors may help to identify patients who are more likely to develop RCDD and require careful medical supervision.

A randomized placebo-controlled trial of Saccharomyces boulardii in combination with standard antibiotics for Clostridium difficile disease.

OBJECTIVE--To determine the safety and efficacy of a new combination treatment for patients with Clostridium difficile-associated disease (CDD). The treatment combines the yeast Saccharomyces boulardii with an antibiotic (vancomycin hydrochloride or metronidazole). DESIGN--A double-blind, randomized, placebo-controlled, parallel-group intervention study in patients with active CDD. Patients received standard antibiotics and S boulardii or placebo for 4 weeks, and were followed up for an additional 4 weeks after therapy. Effectiveness was determined by comparing the recurrence of CDD in the two groups using multivariate analysis to control for other risk factors for CDD. SETTING--National referral study of ambulatory or hospitalized patients from three main study coordinating centers. PATIENTS--A total of 124 eligible consenting adult patients, including 64 who were enrolled with an initial episode of CDD, and 60 who had a history of at least one prior CDD episode. Patients who were immunosuppressed due to acquired immunodeficiency syndrome or cancer chemotherapy within 3 months were not eligible. INTERVENTION--Treatment with oral S boulardii (1 g/d for 4 weeks) or placebo in combination with a standard antibiotic. MAIN OUTCOME MEASURE--Recurrence of active CDD. RESULTS--A history of CDD episodes dramatically increased the likelihood of further recurrences. Multivariate analysis revealed that patients treated with S boulardii and standard antibiotics had a significantly lower relative risk (RR) of CDD recurrence (RR, 0.43; 95% confidence interval, 0.20 to 0.97) compared with placebo and standard antibiotics. The efficacy of S boulardii was significant (recurrence rate 34.6%, compared with 64.7% on placebo; P = .04) in patients with recurrent CDD, but not in patients with initial CDD (recurrence rate 19.3% compared with 24.2% on placebo; P = .86). There were no serious adverse reactions associated with S boulardii. CONCLUSIONS--The combination of standard antibiotics and S boulardii was shown to be an effective and safe therapy for these patients with recurrent CDD; no benefit of S boulardii was demonstrated for those with an initial episode of CDD.

Immunoglobulin G directed against toxins A and B of Clostridium difficile in the general population and patients with antibiotic-associated diarrhea.

Serum immunoglobulin G (IgG) class antibodies directed against toxins A and B of Clostridium difficile were studied using an enzyme-linked immunosorbent assay and a serum-neutralizing assay based on the MRC-5 tissue cytotoxicity assay. Of 185 individuals, 46 sera (24%) in the general population demonstrated IgG antibody, 36 (19.4%) against toxin A and 15 (8.1%) against toxin B. Antibody titer in the general population did not correlate with serum-neutralizing activity. Antibody prevalence fell with age (P = 0.58) over 50 years. Six of ten patients with acute primary episodes of C. difficile-associated diarrhea demonstrated antibody in convalescent-phase sera, predominantly directed against toxin B. Only two (28%) of seven patients with a history of relapsing C. difficile disease had demonstrable antibody.

Diagnosis and treatment of Clostridium difficile colitis.

Pseudomembranous colitis associated with antibiotic therapy is almost always due to an overgrowth of Clostridium difficile. If untreated, pseudomembranous colitis can lead to severe diarrhea, hypovolemic shock, toxic dilatation of the colon, cecal perforation, hemorrhage, and death. However, C difficile-associated colitis can mimic the more common "benign" antibiotic-associated diarrhea that is not caused by C difficile. An algorithm for diagnosis management of hospitalized patients with antibiotic diarrhea and C difficile colitis is presented in this review. Diagnosis depends on sigmoidoscopy and/or stool tests for C difficile toxins in all patients with antibiotic-associated diarrhea. If the results of these tests are positive, either metronidazole or vancomycin is recommended for treatment of mild illness, and vancomycin is recommended for treatment of severe illness. Oral therapy is always preferred because it is more reliable. In patients with recurrent or relapsing colitis, treatment with either metronidazole or vancomycin is effective for that episode, but novel approaches, such as the oral or rectal introduction of competing nonpathogenic organisms, may prove to be more successful in prevention of relapses.

Evaluation of new anti-infective drugs for the treatment of acute infectious diarrhea. Infectious Diseases Society of America and the Food and Drug Administration.

This guideline includes diarrhea causing infantile mortality in which a bacterial pathogen is recovered and for which oral rehydration therapy is an important component of care as well as traveler's diarrhea (with or without recovery of a pathogen). Diarrhea is defined as the passage of three or more unformed stools per day plus--in all patients except infants--one or more signs or symptoms of enteric infection. The preferred study design is prospective and randomized, with an active concurrent control and (when possible) blinding. Placebo-controlled trials may be performed if the severity of disease is judged by the investigator to be mild or moderate. It is desirable that both clinical and microbiological outcome be determined. Microbiological eradication is paramount.

Evaluation of new anti-infective drugs for the treatment of typhoid fever. Infectious Diseases Society of America and the Food and Drug Administration.

Typhoid fever is an acute febrile illness caused by Salmonella typhi. The evidence of blood-borne infection required for study entry includes clinical signs and symptoms plus confirmation of the presence of S. typhi in blood or other tissues or body fluids. The preferred study design is prospective and randomized with an active concurrent control. It is preferred that the investigator or an evaluator be blinded to therapy. In general, treatment should be administered for 2 weeks until it is demonstrated that a shorter course is as efficacious and as safe. Follow-up cultures of specimens from sites originally shown to be infected with S. typhi should be performed unless the diagnostic procedure places the patient at unnecessary risk.

Evaluation of new anti-infective drugs for the treatment of cholera. Infectious Diseases Society of America and the Food and Drug Administration.

Cholera is an acute gastrointestinal infection caused by Vibrio cholerae. It is characterized by watery diarrhea that may lead to massive fluid loss, which in turn may result in hypotension, shock, and death within hours. Key to the treatment of cholera is fluid replacement. Anti-infective therapy decreases the severity and duration of diarrhea and the duration of shedding of V. cholerae. Enrolled patients should have diarrhea that is moderate to severe and a culture that ultimately yields V. cholerae. A prospective, randomized, active-controlled clinical trial is preferred. Studies should be double-blinded or evaluator-blinded. The rapidity with which the organism is eliminated from stool may be assessed. Both clinical and microbiological outcome should be determined. Assessment of microbiological eradication is paramount, since fluid replacement may suffice for treatment of signs and symptoms.

Evaluation of new anti-infective drugs for the treatment of diarrhea caused by Giardia lamblia. Infectious Diseases Society of America and the Food and Drug Administration.

Giardia lamblia is a flagellate protozoan that produces symptoms by infecting the small bowel and biliary tract in the trophozoite form. Diagnosis is currently established by microscopic visualization of the organism in appropriate intestinal contents (stool, small-bowel contents, or biopsy specimen). Adult patients with diarrhea and one or more enteric symptoms may be enrolled in clinical trials of new drugs for the treatment of giardial disease. A randomized, double-blind, active-concurrent-control design is recommended. Post hoc stratification by age, immune status, chronicity of disease, and ease of establishing diagnosis (organism load) may be performed. Microbiological assessment 48 hours to 7 days after the completion of therapy is paramount for determining final outcome.

Evaluation of new anti-infective drugs for the treatment of diarrhea caused by Cryptosporidium. Infectious Diseases Society of America and the Food and Drug Administration.

Cryptosporidium is a coccidian protozoan that produces symptoms by infesting the small bowel. The illness is characterized by watery stools, anorexia, weight loss, and abdominal pain. Diagnosis is made by visualization of the organisms on microscopic examination of stool. There currently is no approved therapy for this infection. A randomized, double-blind, placebo-controlled study design is recommended. Stratification of patients by age and immune status should be considered. Two stool samples obtained 48 hours to 7 days after completion of therapy should be negative for Cryptosporidium oocysts. Assessment of microbiological outcome is paramount.

Evaluation of new anti-infective drugs for the treatment of diarrhea caused by Entamoeba histolytica. Infectious Diseases Society of America and the Food and Drug Administration.

Entamoeba histolytica causes colonic infection that ranges from asymptomatic carriage to invasive disease with infection of extraintestinal organs, particularly the liver. The disease occurs in both sporadic and epidemic forms. Diagnosis requires visualization of trophozoites or cysts by microscopic examination of stool, colonic scrapings, or biopsy specimens. Patients with either asymptomatic or symptomatic disease may be eligible for clinical trials. A prospective, randomized, double-blind, placebo-controlled study design is recommended for asymptomatic carriers and an active-concurrent-control study design for symptomatic patients. Final outcome should be assessed 48 hours to 7 days after completion of therapy. Assessment of microbiological outcome is paramount.

Evaluation of new anti-infective drugs for the treatment of chronic carriage of Salmonella. Infectious Diseases Society of America and the Food and Drug Administration.

The chronic carriage of salmonellae is defined as the shedding of a Salmonella species for > or = 1 year, as documented by an initial positive culture of a stool sample obtained at least 1 month after resolution of the acute illness and repeated positive cultures for at least 1 year. Clinical trials of investigational anti-infective drugs for the treatment of the salmonella carrier state may be conducted with a placebo control or an active concurrent control. A crossover design also may be employed for establishing efficacy. Patients should generally receive therapy for at least 6 weeks. Outcome will be assessed only by microbiological criteria. Determination of the interval required for the suppression of salmonellae and follow-up for 6 months after completion of therapy are recommended.

Evaluation of new anti-infective drugs for the treatment of antibiotic-associated colitis. Infectious Diseases Society of America and the Food and Drug Administration.

Colitis due to Clostridium difficile is diagnosed in 10%-15% of hospitalized patients who develop diarrhea after treatment with antimicrobial drugs. Diagnosis is based on the concurrence of diarrhea, one or more signs or symptoms of enteric intoxication, and stool from which toxigenic C. difficile is isolated or from which its toxins are identified. Clinical trials evaluating therapy may be placebo controlled (for mild disease) or concurrently controlled with an active drug. A randomized, double-blind study design is preferred. Outcome should be assessed by monitoring of the degree of inflammation of the bowel mucosa, the intensity and severity of diarrhea, the duration of illness, changes in stool form, and the eradication of C. difficile or its toxins from stool. Because C. difficile can be a component of the normal gastrointestinal flora, assessment of clinical outcome is paramount.

Evaluation of new anti-infective drugs for the treatment of gastritis and peptic ulcer disease associated with infection by Helicobacter pylori. Infectious Diseases Society of America and the Food and Drug Administration.

Helicobacter pylori is a gram-negative, microaerophilic, spiral bacillus. Infection by this organism is currently believed to be the major cause of type B gastritis. Inflammation and infection may persist for years in the absence of therapeutic intervention. There is currently no approved antimicrobial therapy for gastritis. Clinical investigations have shown that combination regimens including bismuth salts and antimicrobial drugs result in the relief of symptoms, the resolution of histologic evidence of gastritis, the eradication of H. pylori, high rates of ulcer healing, and lower rates of ulcer relapse than have been found with other therapies (antacids and H2 antagonists). A randomized, double-blind, placebo-controlled study design is recommended for evaluation of new therapies. Study participants should have their progress monitored by endoscopy performed at enrollment, at completion of therapy, and 3 months thereafter. Assessment of microbiological outcome is paramount for final evaluation of the patient.

In vitro synergy studies with Clostridium difficile.

Agar dilution anaerobic susceptibility studies using rifampin, vancomycin, metronidazole, and bacitracin individually and in combination were performed with Clostridium difficile. Fifty-five strains of C. difficile were studied. Eighty-five percent of strains tested (29 of 34) were synergistically inhibited by the combination of bacitracin and rifampin (fractional inhibitory concentration, less than or equal to 0.50).

Treatment of antibiotic-associated Clostridium difficile colitis with oral vancomycin: comparison of two dosage regimens.

PURPOSE: High-dose (500 mg orally four times daily) vancomycin is considered by many investigators to be the most effective treatment for antibiotic-associated Clostridium difficile colitis. However, a lower dosage of 125 or 150 mg given three or four times a day has become popular, has been shown to be effective, and is less expensive than the high-dose regimen. We therefore decided to compare two vancomycin dosage regimens in a randomized trial. PATIENTS AND METHODS: The study involved 46 hospitalized patients with serious underlying diseases complicated by C. difficile diarrhea or colitis. Patients were assigned (according to a table of random numbers) to treatment with either 125 or 500 mg of vancomycin orally four times daily for an average of 10 days. RESULTS: No significant differences in measurable responses to the two regimens were noted. There were no treatment failures. The mean duration of diarrhea after initiation of therapy was about four days, and almost all patients had no diarrhea after one week. The organism continued to be demonstrated in the stools of about 50 percent of patients for the first few weeks after completion of therapy, and nine (20 percent) patients developed a recurrence of their diarrheal illness. Vancomycin was well tolerated by all patients. CONCLUSION: Since the dose of 125 mg appeared to be as effective as the 500-mg dose, which is more expensive, the 125-mg dose is preferred when vancomycin is used in treatment of this disease, unless the patient is critically ill.