Antibiotic prescribing policy and Clostridium difficile diarrhoea

Prevention of Clostridium difficile Infection and Associated Diarrhea: An Unsolved Problem

For many years, it has been known that Clostridium difficile (CD) is the primary cause of health-care-associated infectious diarrhea, afflicting approximately 1% of hospitalized patients. CD may be simply carried or lead to a mild disease, but in a relevant number of patients, it can cause a very severe, potentially fatal, disease. In this narrative review, the present possibilities of CD infection (CDI) prevention will be discussed. Interventions usually recommended for infection control and prevention can be effective in reducing CDI incidence. However, in order to overcome limitations of these measures and reduce the risk of new CDI episodes, novel strategies have been developed. As most of the cases of CDI follow antibiotic use, attempts to rationalize antibiotic prescriptions have been implemented. Moreover, to reconstitute normal gut microbiota composition and suppress CD colonization in patients given antimicrobial drugs, administration of probiotics has been suggested. Finally, active and passive immunization has been studied. Vaccines containing inactivated CD toxins or components of CD spores have been studied. Passive immunization with monoclonal antibodies against CD toxins or the administration of hyperimmune whey derived from colostrum or breast milk from immunized cows has been tried. However, most advanced methods have significant limitations as they cannot prevent colonization and development of primary CDI. Only the availability of vaccines able to face these problems can allow a resolutive approach to the total burden due to this pathogen.

In vitro antivirulence activity of baicalin against Clostridioides difficile

Introduction. Clostridioides difficile is an enteric pathogen that causes a serious toxin-mediated colitis in humans. Bacterial exotoxins and sporulation are critical virulence components that contribute to pathogenesis, and disease transmission and relapse, respectively. Therefore, reducing toxin production and sporulation could significantly minimize C. difficile pathogenicity and disease outcome in affected individuals.

Aim. This study investigated the efficacy of a natural flavone glycoside, baicalin, in reducing toxin synthesis, sporulation and spore germination in C. difficile in vitro.

Methodology. Hypervirulent C. difficile isolates BAA 1870 or 1803 were cultured in brain heart infusion broth with or without the subinhibitory concentration (SIC) of baicalin, and incubated at 37 °C for 24 h under strictly anaerobic conditions. The supernatant was harvested after 24 h for determining C. difficile toxin production by ELISA. In addition, a similar experiment was performed wherein samples were harvested for assessing total viable counts, and heat-resistant spore counts at 72 h of incubation. Furthermore, C. difficile spore germination and spore outgrowth kinetics, with or without baicalin treatment, was measured in a plate reader by recording optical density at 600 nm. Finally, the effect of baicalin on C. difficile toxin, sporulation and virulence-associated genes was investigated using real-time quantitative PCR.

Results. The SIC of baicalin significantly reduced toxin synthesis, sporulation and spore outgrowth when compared to control. In addition, C. difficile genes critical for pathogenesis were significantly down-regulated in the presence of baicalin.

Conclusion. Our results suggest that baicalin could potentially be used to control C. difficile , and warrant future studies in vivo.

Impact of Chlorhexidine Bathing on Antimicrobial Utilization in Surgical Intensive Care Unit

BACKGROUND

This secondary analysis compared antimicrobial utilization among surgical intensive care unit patients randomized to every other day chlorhexidine bathing (chlorhexidine) versus daily soap and water bathing (soap-and-water) using data from the CHlorhexidine Gluconate BATHing trial.

MATERIALS AND METHODS

Antimicrobial utilization was quantified using defined daily dose (DDD)/100 patient-days and agent-days/100 patient-days for systemic antimicrobials. Antivirals (except oseltamivir), antiparasitics, and prophylaxis agents were excluded. The 2018 anatomic therapeutic chemical/DDD index was used to calculate DDD. Agent-days were calculated as the sum of calendar days where antimicrobials were administered. Patient-days were defined as time patients were at risk for health care-acquired infections plus up to 14 d. Primary analyses were conducted using linear regression adjusted for baseline Acute Physiology and Chronic Health Evaluation II scores.

RESULTS

Of 325 CHlorhexidine Gluconate BATHing trial patients, 312 (157 in soap-and-water and 155 in chlorhexidine) were included. The median (interquartile range) of total antimicrobial DDD/100 patient-days was 135.4 (75.2-231.8) for soap-and-water and 129.9 (49.2-215.3) for chlorhexidine. The median (interquartile range) of total antimicrobial agent-days/100 patient-days was 155.6 (83.3-243.2) for soap-and-water and 146.7 (66.7-217.4) for chlorhexidine. After adjusting for Acute Physiology and Chronic Health Evaluation II scores, chlorhexidine bathing was associated with a nonsignificant reduction in total antimicrobial DDD/100 patient-days (-3.9; 95% confidence interval, -33.9 to 26.1; P = 0.80) and total antimicrobial agent-days/100 patient-days (-10.3; 95% confidence interval, -34.7 to 14.1; P = 0.41).

CONCLUSIONS

Compared with daily soap and water bathing, every other day chlorhexidine bathing did not significantly reduce total antimicrobial utilization in surgical intensive care unit patients.

Value of antibiotic prophylaxis in routine knee arthroscopy : A retrospective study

OBJECTIVE

Prophylactic antibiotic use prior to routine knee arthroscopy remains controversial. It is important to know whether antibiotics help decrease the surgical site infection (SSI) rate. Our aims were to assess the efficacy of antibiotic prophylaxis in preventing SSI and to identify risk factors for SSI following routine knee arthroscopy without an implant.

METHODS

A retrospective study was conducted using the electronic medical records at the authors' hospital to identify patients that underwent routine knee arthroscopy without an implant between October 2010 and October 2016. Data on demographics, clinical characteristics and antibiotic administration were extracted. Arthroscopic diagnosis, debridement, partial or complete meniscectomy, arthroscopic shaving and microfracture, removal of loose bodies, synovectomy and lateral retinacular release were included. Complex knee arthroscopy with an implant was excluded. Patients were divided into evaluation (with prophylactic antibiotics) and control (no antibiotic treatment) groups. Continuous variables between groups were compared using the Student's t-test. Data were analyzed using the Chi-squared test for percentages between groups. Multivariate logistic regression was used to identify independent risk factors of SSI.

RESULTS

Of 1326 patients, 614 (46.3%) received prophylactic antibiotics, while 712 (53.7%) did not. There were seven (0.53%) SSIs. The SSI rate did not differ significantly between patients receiving antibiotics (0.49%, three) and those not (0.56%, four). Five patients (0.37%) had superficial infections, two (0.33%) were in the prophylactic antibiotic group and three (0.42%) were in the other group. Deep infections occurred in two patients (0.15%), one (0.16%) in the prophylactic antibiotic group and one (0.14%) in the other group. The difference between the two groups was not statistically significant (P = 1.0). Age over 50 years was associated with an increased risk of SSI (relative ratio [RR] = 1.469, 95% confidence interval [CI] 1.09-2.13, P = 0.009).

CONCLUSIONS

Prophylactic antibiotic use in routine knee arthroscopy without an implant may not be necessary. Age over 50 years was associated with an increased risk of SSI.

In vitro efficacy of sodium selenite in reducing toxin production, spore outgrowth and antibiotic resistance in hypervirulent Clostridium difficile

PURPOSE

This study investigated the efficacy of the essential mineral, selenium (sodium selenite), in reducing the toxin production, spore outgrowth and antibiotic resistance of Clostridium difficile in vitro.

METHODOLOGY

Two hypervirulent C. difficile isolates were cultured in brain heart infusion broth with and without a sub-minimum inhibitory concentration (sub-MIC) of sodium selenite, and the supernatant and bacterial pellet were harvested for total toxin quantitation and RT-qPCR analysis of toxin-encoding genes, respectively. Additionally, C. difficile isolates were cultured in brain heart infusion broth containing 0.5 or 1× the minimum inhibitory concentration (MIC) of either ciprofloxacin or vancomycin with or without sub-MICs of sodium selenite. Further, the effect of sodium selenite on C. difficile germination and spore outgrowth was also determined by exposing C. difficile spores to a sub-MIC of sodium selenite in a germination medium and measuring the germination and outgrowth by measuring the optical density at 600  nm.

RESULTS

Sodium selenite significantly reduced C. difficile toxin synthesis, cytotoxicity and spore outgrowth. Further, the expression of the toxin production genes, tcdA and tcdB, was downregulated in the presence of sodium selenite, while sodium selenite significantly increased the sensitivity of C. difficile to ciprofloxacin , but not vancomycin, as revealed by decreased bacterial growth in samples containing ciprofloxacin+selenium compared to the antibiotic control. Although the sub-MIC of sodium selenite did not inhibit spore germination, it was capable of completely inhibiting spore outgrowth.

CONCLUSION

Our results suggest that sodium selenite could potentially be used to control C. difficile and indicate that future in vivo studies are warranted.

National epidemiology of initial and recurrent Clostridium difficile infection in the Veterans Health Administration from 2003 to 2014

Introduction

Prior studies demonstrated marked increases in Clostridium difficile infection (CDI) in the United States (U.S.) in recent years. The objective of this study was to describe the epidemiology of initial and recurrent CDI in a national Veterans Health Administration (VHA) cohort over a 12-year period.

Methods

This was a retrospective cohort study of all adult VHA beneficiaries with CDI (ICD-9-CM code 008.45) plus a positive CDI stool test between October 1, 2002 and September 30, 2014. Data were obtained from the VA Informatics and Computing Infrastructure. Recurrence was defined as a second ICD-9-CM code plus a new course of CDI therapy following a minimum three-day gap after the initial therapy was completed. CDI incidence and outcomes were presented descriptively and longitudinally.

Results

Overall, 30,326 patients met study inclusion criteria. CDI incidence increased from FY 2003 (1.6 per 10,000) to FY 2013 (5.1 per 10,000). Thereafter, CDI incidence decreased through FY 2014 (4.6 per 10,000). A total of 5,011 patients (17%) experienced a first recurrence and, of those, 1,713 (34%) experienced a second recurrence. Recurrence incidence increased 10-fold over the study period, from (0.1 per 10,000) in FY 2003, to (1.0 per 10,000) in FY 2014. Overall, 30-day mortality and median hospital length of stay (LOS) decreased among initial episodes over the study period. Mortality was higher for initial episodes (21%) compared to first recurrences (11%) and second recurrences (7%). Median hospital LOS was longer for first episodes (13 days) compared to first (9 days) and second recurrences (8 days).

Conclusions

Initial and recurrent CDI episodes increased among veterans over a 12-year period. Outcomes, such as mortality and hospital LOS improved in recent years; both of these outcomes are worse for initial CDI episodes than recurrent episodes.

Clostridium difficile infection: new approaches to prevention, non-antimicrobial treatment, and stewardship

INTRODUCTION

Despite the large amount of scientific publications exploring the epidemiology and the clinical management of Clostridium difficile (CD) infection, some issues remain unsolved or need further studies. The aim of this review is to give an update on the hot topics on CD prevention, including stewardship programs, and on the non-microbiological treatment of CD infection. Areas covered: This article will review the importance of minimizing the CD spore shedding in the healthcare environment for potentially reducing CD transmission. Moreover, antimicrobial stewardship programs aimed to reduce CD incidence will be reviewed. Finally, new strategies for reducing CD infection recurrence will be described. Expert commentary: Besides the basic infection control and prevention practices, including hand hygiene, contact isolation and environmental cleaning, in the prevention of CD infection other issues should be addressed including minimizing the spread of CD in the healthcare setting, and implementing the best strategy for reducing CD infection occurrence, including tailored antimicrobial stewardship programs. Regarding new advancements in treatment and management of CDI episodes, non-antimicrobial approaches seem to be promising in reducing and managing recurrent CD infection.

Carvacrol reduces Clostridium difficile sporulation and spore outgrowth in vitro

PURPOSE

Clostridium difficile is an anaerobic spore-forming pathogen that causes a serious toxin-mediated enteric disease in humans. Therapeutic agents that are capable of reducing C. difficile spore production could significantly minimize the transmission and relapse of C. difficile infections. This study investigated the efficacy of a food-grade, plant-derived compound, carvacrol (CR), in reducing C. difficile spore production, germination and spore outgrowth.

METHODOLOGY

Two hyper-virulent C. difficile isolates (ATCC BAA 1870 and 1805) were grown with or without a sub-inhibitory concentration (SIC) of CR. Total viable counts and heat-resistant spore counts were determined at different time intervals. Moreover, spores and vegetative cells were visualized using phase-contrast microscopy. To determine the effect of CR on C. difficile germination and spore outgrowth, C. difficile spores were seeded in germination medium with or without the SIC and MIC of CR, and spore germination and spore outgrowth were measured by recording optical density at 600 nm. The effect of CR on C. difficile sporulation genes was also investigated using real-time qPCR.

RESULTS

Carvacrol significantly reduced sporulation in C. difficile and down-regulated critical genes involved in spore production (P<0.05). The SIC or MIC of CR did not inhibit C. difficile spore germination; however, the MIC of CR completely inhibited spore outgrowth.

CONCLUSION

The results suggest that CR could potentially be used to control C. difficile by reducing spore production and outgrowth.

Antibiotic prophylaxis for surgical site infections as a risk factor for infection with Clostridium difficile

Objective

We aimed to measure the association between 2013 guideline concordant prophylactic antibiotic use prior to surgery and infection with Clostridium difficile.

Design

We conducted a retrospective case-control study by selecting patients who underwent a surgical procedure between January 1, 2012 and December 31, 2013.

Setting

Large urban community hospital.

Patients

Cases and controls were patients age 18+ years who underwent an eligible surgery (i.e., colorectal, neurosurgery, vascular/cardiac/thoracic, hysterectomy, abdominal/pelvic and orthopedic surgical procedures) within six months prior to infection diagnosis. Cases were diagnosed with C. difficile infection while controls were not.

Methods

The primary exposure was receiving (vs. not receiving) the recommended prophylactic antibiotic regimen, based on type and duration. Potential confounders included age, sex, length of hospital stay, comorbidities, type of surgery, and prior antibiotic use. Crude and adjusted odds ratios (OR) and 95% confidence intervals (CI) were calculated using logistic regression.

Results

We enrolled 68 cases and 220 controls. The adjusted OR among surgical patients between developing C. difficile infection and not receiving the recommended prophylactic antibiotic regimen (usually receiving antimicrobial prophylaxis for more than 24 hours) was 6.7 (95% CI: 2.9–15.5). Independent risk factors for developing C. difficile infection included having severe comorbidities, receiving antibiotics within the previous 6 months, and undergoing orthopedic surgery.

Conclusions

Adherence to the recommended prophylactic antibiotics among surgical patients likely reduces the probability of being case of C. difficile. Antibiotic stewardship should be a priority in strategies to decrease the morbidity, mortality, and costs associated with C. difficile infection.

Protective Effect of Carvacrol against Gut Dysbiosis and Clostridium difficile Associated Disease in a Mouse Model

This study investigated the effect of carvacrol (CR), a phytophenolic compound on antibiotic-associated gut dysbiosis and C. difficile infection in a mouse model. Five to six-week-old C57BL/6 mice were randomly divided into seven treatment groups (challenge and control) of eight mice each. Mice were fed with irradiated feed supplemented with CR (0, 0.05, and 0.1%); the challenge groups were made susceptible to C. difficile by orally administering an antibiotic cocktail in water and an intra-peritoneal injection of clindamycin. Both challenge and control groups were infected with 10⁵CFU/ml of hypervirulent C. difficile (ATCC 1870) spores or PBS, and observed for clinical signs for 10 days. Respective control groups for CR, antibiotics, and their combination were included for investigating their effect on mouse enteric microflora. Mouse body weight and clinical and diarrhea scores were recorded daily post infection. Fecal samples were collected for microbiome analysis using rRNA sequencing in MiSeq platform. Carvacrol supplementation significantly reduced the incidence of diarrhea and improved the clinical and diarrhea scores in mice (p < 0.05). Microbiome analysis revealed a significant increase in Proteobacteria and reduction in the abundance of protective bacterial flora in antibiotic-treated and C. difficile-infected mice compared to controls (p < 0.05). However, CR supplementation positively altered the microbiome composition, as revealed by an increased abundance of beneficial bacteria, including Firmicutes, and significantly reduced the proportion of detrimental flora such as Proteobacteria, without significantly affecting the gut microbiome diversity compared to control. Results suggest that CR could potentially be used to control gut dysbiosis and reduce C. difficile infection.

Drug utilization review of cephalosporins in a secondary care hospital in United Arab Emirates

Background Cephalosporins are one of the most commonly used antibiotics in United Arab Emirates (UAE). Few studies have been carried out to evaluate the antibiotic utilization pattern in UAE in spite of the obvious increase in cephalosporins resistance during the past decade. Objective To assess the prescriptions pattern of cephalosporins among physicians at a secondary care hospital in Ras Al Khaimah, UAE. Method This observational prospective study was carried out during October 2013 to April 2014. The data of in patients were documented in the predesigned patient profile form and was analyzed for patient's, drug's and drug's therapy related parameters. Results The 3rd generation cephalosporins constituted 83.6 % of the prescriptions, with ceftriaxone being the most commonly used one (81.1 %). They were mainly prescribed for the treatment of the lower respiratory tract infections (60.2 %). Seven (3.5 %) different ADRs linked to cephalosporin use were observed ranging from oral thrush to clostridium difficile infection. A total of 1039 antimicrobial and nonantimicrobial medications were prescribed concomitantly with cephalosporins. Conclusion The 3rd generation cephalosporins were commonly prescribed by parenteral route. Thus, there is a strong need for rationalizing their use to preserve their efficacy and prevent the development of resistance in the region.

Low vitamin D level and impact on severity and recurrence of Clostridium difficile infections

BACKGROUND

Clostridium difficile infection (CDI) has recently markedly increased, incurring greater health care-associated costs and hospitalizations especially in vitamin D deficient patients. Accordingly, the aim of this study was to evaluate the relationship between low vitamin D levels and the severity and recurrence of CDI.

METHODS

A retrospective case-control study evaluated patients hospitalized between 2007 and 2013 with CDI and a positive C. difficile toxin assay. Severe complicated CDI was defined based on (1) laboratory or radiological criteria correlated clinically and (2) sepsis requiring intensive care unit admission. Recurrent CDI (RCDI) was defined as a new episode of diarrhea occurring within 90 days of resolution of the initial episode for at least 10 days after discontinuing therapy and confirmed by positive stool C. difficile toxin assay or polymerase chain reaction. Patients were divided into 4 groups based on vitamin D level (ng/mL): severely deficient (<10), insufficient (10-19.9), predeficient (20-29.9), and control group (≥30).

RESULTS

Two hundred seventy-one patients were diagnosed with CDI, of which 48 had RCDI distributed as 5 (12.5%), 15 (16.1%), 10 (15.6%), and 13 (17.5%) patients in each of the aforementioned groups, respectively (P=0.55). Severe complicated CDI was identified in 7 (17.5%), 17 (18.2%), 9 (14%), and 3 (4%) patients, respectively (P=0.04). Thirty-day mortality was 1 of 40, 1 of 93, 2 of 64, and 2 of 74 patients, respectively (P=0.43).

CONCLUSIONS

Normal vitamin D level has a protective effect against severe CDI, and low vitamin D is associated with greater severity of CDI but not with an increased risk of RCDI or 30-day mortality.

Clostridium difficile colitis: review of the therapeutic approach

Clostridium difficile infection (CDI) is the leading cause of antibiotic-associated and nosocomial infectious diarrhea. Presenting as clostridium difficile colitis, it is a significant cause of morbidity and mortality. Metronidazole is regarded as the agent of choice for CDl therapy and also for the first recurrence in most patients with mild to moderate CDI. Vancomycin is recommended as an initial therapy for patients with severe CDI. With recent Food and Drug Administration-approval fidaxomicin is available for clinical use and is as effective as vancomycin with lower relapse rates. Rifaximin and fecal bacteriotherapy are alternative approaches in patients with severe or refractory CDI, before surgical intervention. Antibiotic research is ongoing to add potential new drugs such as teicoplanin, ramoplanin, fusidic acid, nitazoxanide, rifampin, bacitracin to our armamentarium. Role of toxin-binding agents is still questionable. Monoclonal antibody and intravenous immunoglobulin are still investigational therapies that could be promising options. The ongoing challenges in the treatment of CDI include management of recurrence and presence of resistance strains such as NAP1/BI/027, but early recognition of surgical candidates can potentially decrease mortality in CDI.

Antibiotic resistance as collateral damage: the tragedy of the commons in a two-disease setting

We propose a simple two-disease epidemic model where one disease exhibits only a drug-sensitive strain, while the other exhibits both drug-sensitive and drug-resistant strains. Treatment for the first disease may select for resistance in the other. We model antibiotic use as a mathematical game through the study of individual incentives and community welfare. The basic reproduction number is derived and the existence and local stability of the model equilibria are analyzed. When the force of infection of each disease is unaffected by the presence of the other, we find that there is a conflict of interest between individual and community, known as a tragedy of the commons, under targeted treatment toward persons infected by the single strain disease, but there is no conflict under mass treatment. However, we numerically show that individual and social incentive to use antibiotics may show disaccord under mass treatment if the restriction on the transmission ability of the dually infected people is removed, or drug resistant infection is worse than drug sensitive infection, or the uninfected state has a comparative disutility over the infected states.

Prophylactic antibiotics in dermatological surgery

This is a review of the common pathogens of surgical site infections, antibiotic coverage for particular anatomical sites, mechanisms by which surgical site infections occur and the latest data and recommendations for prophylactic antibiotics in the prevention of surgical site infections, infective endocarditis and haematogenous joint infections. Recent evidence-based guidelines on surgical prophylaxis is for restricted indications and a shorter duration of antibiotic prophylaxis in situations where no clinical benefit of prolonged therapy has been proven, in order to minimise the potential adverse ecological and clinical effects associated with antibiotic therapy. This review recommends the cautious use of prophylactic antibiotics in dermatological surgery to help prevent the growing problem of bacterial resistance as well as other morbidity and health-care costs.

The rise in Clostridium difficile infection incidence among hospitalized adults in the United States: 2001-2010

BACKGROUND

Clostridium difficile infection (CDI) incidence is a growing concern. This study provides national estimates of CDI over 10 years and identifies trends in mortality and hospital length of stay (LOS) among hospitalized adults with CDI.

METHODS

We conducted a retrospective analysis of the US National Hospital Discharge Surveys from 2001-2010. Eligible cases included adults aged ≥ 18 years discharged from a hospital with an ICD-9-CM diagnosis code for CDI (008.45). Data weights were used to derive national estimates. CDI incidence rates were depicted as CDI discharges per 1,000 total adult discharges.

RESULTS

These data represent 2.2 million adult hospital discharges for CDI over the study period. CDI incidence increased from 4.5 CDI discharges per 1,000 total adult discharges in 2001 to 8.2 CDI discharges per 1,000 total adult discharges in 2010. The overall in-hospital mortality rate was 7.1% for the study period. Mortality increased slightly over the study period, from 6.6% in 2001 to 7.2% in 2010. Median hospital LOS was 8 days (interquartile range, 4-14 days), and remained stable over the study period.

CONCLUSIONS

The incidence of CDI among hospitalized adults in the United States nearly doubled from 2001-2010. Furthermore, there is little evidence of improvement in patient mortality or hospital LOS.

[Clostridium difficile infections in Spanish Internal Medicine departments during the period 2005-2010: the burden of the disease]

INTRODUCTION

Clostridium Difficile infection (CDI) is increasing in Spain. A review is presented of this infection in order to evaluate the burden of the disease in this country.

MATERIAL

An analytical retrospective and descriptive study was conducted by analyzing the Minimum Basic Data Set of patients admitted to Internal Medicine Departments and with and without CDI between the years 2005-2010. Clinical and demographical variables were compared.

RESULTS

Mean age was 75.5 years (SD 15.4), 54.9% were women and mean stay was 22.2 days (SD 24.8). The Cost [(€ 5,001 (SD 4,985) vs [€ 3,934 (SD 2,738)] and diagnostic complexity [2.04 (SD 2.62) vs [1.67 (SD 1.47)] were also different. Mortality for all causes was 12.5% vs 9.8%. Death risk showed a 30% increase (odds ratio 1.30, 95% confidence interval;1.21-1.39) and readmission rate was 30.4% vs 13.5%. Distribution of cases showed season variations (more cases in winter), and annual incidence increased during the study period. Comorbidities associated to increased risk of acquiring CDI were: anemia, human immunodeficiency virus, dementia, malnutrition, chronic renal failure, and living in a nursing home.

CONCLUSION

The results showed a clear negative impact of CDI on hospital admissions. A trend towards progression in its incidence without changes in mortality or readmission rates was observed, in common with the rest of Europe and the Western World.

Effect of antibiotic stewardship programmes on Clostridium difficile incidence: a systematic review and meta-analysis

OBJECTIVES

Despite vigorous infection control measures, Clostridium difficile continues to cause significant disease burden. Antibiotic stewardship programmes (ASPs) may prevent C. difficile infections by limiting exposure to certain antibiotics. Our objective was to perform a meta-analysis of published studies to assess the effect of ASPs on the risk of C. difficile infection in hospitalized adult patients.

METHODS

Searches of PubMed, Web of Science, Cumulative Index to Nursing and Allied Health Literature and two Cochrane databases were conducted to find all published studies on interventions related to antibiotic stewardship and C. difficile. Two investigators independently assessed study eligibility and extracted data. Risk of bias was assessed using the Downs and Black tool. Risk ratios were pooled using random effects models. Heterogeneity was evaluated using the I(2) statistic.

RESULTS

The final search yielded 891 articles; 78 full articles were reviewed and 16 articles were identified for inclusion. Included articles used quasi-experimental (interrupted time series or before-after) or observational (case-control) study designs. When the results of all studies were pooled in a random effects model, a significant protective effect (pooled risk ratio 0.48; 95% CI: 0.38, 0.62) was observed between ASPs and C. difficile incidence. When stratified by intervention type, a significant effect was found for restrictive ASPs (complete removal of drug or prior approval requirement). Furthermore, ASPs were particularly effective in geriatric settings.

CONCLUSIONS

Restrictive ASPs can be used to reduce the risk of C. difficile infection.

Carvacrol and trans-cinnamaldehyde reduce Clostridium difficile toxin production and cytotoxicity in vitro

Clostridium difficile is a nosocomial pathogen that causes a serious toxin-mediated enteric disease in humans. Reducing C. difficile toxin production could significantly minimize its pathogenicity and improve disease outcomes in humans. This study investigated the efficacy of two, food-grade, plant-derived compounds, namely trans-cinnamaldehyde (TC) and carvacrol (CR) in reducing C. difficile toxin production and cytotoxicity in vitro. Three hypervirulent C. difficile isolates were grown with or without the sub-inhibitory concentrations of TC or CR, and the culture supernatant and the bacterial pellet were collected for total toxin quantitation, Vero cell cytotoxicity assay and RT-qPCR analysis of toxin-encoding genes. The effect of CR and TC on a codY mutant and wild type C. difficile was also investigated. Carvacrol and TC substantially reduced C. difficile toxin production and cytotoxicity on Vero cells. The plant compounds also significantly down-regulated toxin production genes. Carvacrol and TC did not inhibit toxin production in the codY mutant of C. difficile, suggesting a potential codY-mediated anti-toxigenic mechanism of the plant compounds. The antitoxigenic concentrations of CR and TC did not inhibit the growth of beneficial gut bacteria. Our results suggest that CR and TC could potentially be used to control C. difficile, and warrant future studies in vivo.

The Beta Lactam Antibiotics as an Empirical Therapy in a Developing Country: An Update on Their Current Status and Recommendations to Counter the Resistance against Them

In a developing country like India, where the patients have to bear the cost of their healthcare, the microbiological culture and the sensitivity testing of each and every infection is not feasible. Moreover, there are lacunae in the data storage, management and the sharing of knowledge with respect to the microorganisms which are prevalent in the local geographical area and with respect to the antibiotics which are effective against them. Thus, an empirical therapy for treating infections is imperative in such a setting. The beta lactam antibiotics have been widely used for the empirical treatment of infections since the the discovery of penicillin. Many generations of beta lactams have been launched with, the claims of a higher sensitivity and less resistance, but their sensitivity has drastically decreased over time. Thus, the preference for beta lactams, especially the cephalosporins, as an empirical therapy, among the prescribers was justified initially, but the current sensitivity patterns do not support their empirical use in hospital and community acquired infections. There is a need for increasing the awareness and the attitudinal change among the prescribers, screening of the antibiotic prescriptions, the strict implementation of antibiotic policies in hospital settings, restricting the hospital supplies and avoiding the prescriptions of beta lactams, a regular census of the local sensitivity patterns to formulate and update the antibiotic policies, upgradation of the laboratory facilities for a better and faster detection of the isolates, proper collection, analyses and sharing of the data and the encouragement of the research and development of newer antibiotics with novel mechanisms of action.

Strategies for prevention of Clostridium difficile infection

Infection control is the most essential component of an effective overall management strategy for prevention of nosocomial Clostridium difficile infection (CDI). The cornerstones of CDI prevention are appropriate contact precautions and strict hand hygiene. Other important tactics are effective environmental cleaning, identification and removal of environmental sources of C. difficile, and antibiotic stewardship. Hospitalists, as coordinators of care for each patient and advocates for quality care, can spearhead these efforts.

Infections, bacterial resistance, and antimicrobial stewardship: the emerging role of hospitalists

The care of patients with serious infections both within and outside healthcare settings is increasingly complicated by the high prevalence of resistant or multidrug-resistant (MDR) pathogens. Moreover, infections caused by MDR versus susceptible bacteria or other pathogens are associated with significantly higher mortality, length of hospital stay, and healthcare costs. Antimicrobial misuse or overuse is the primary driver for development of antimicrobial resistance, suggesting that better use of antimicrobials will translate into improved patient outcomes, more efficient use of hospital resources, and lowered healthcare costs. Antimicrobial stewardship refers to the various practices and procedures utilized to optimize antimicrobial use. The primary goal of antimicrobial stewardship is to improve patient outcomes and lower antimicrobial resistance and other unintended consequences of antimicrobial therapy. Secondary goals are to reduce length of hospital stays and healthcare-related costs. Hospitalists are increasingly involved in the care of hospitalized patients throughout the United States. Expertise in managing conditions requiring hospitalization, and experience in quality improvement across a wide range of clinical conditions, make hospitalists well positioned to participate in the development and implementation of hospital-based antimicrobial stewardship programs designed to improve patient outcomes, reduce antimicrobial resistance, and provide more efficient and lower-cost hospital care.

Antimicrobial stewardship for inpatient facilities

Antibiotic stewardship aims to improve patient care and reduce unwanted consequences of antimicrobial overuse or misuse, including lowered efficacy, emergence of antimicrobial resistance, development of secondary infections, adverse drug reactions, increased length of hospital stay, and additional healthcare costs. Recent guidelines make specific recommendations for the development of institutional programs to enhance antimicrobial stewardship. Optimally, such programs should be comprehensive, multidisciplinary, supported by hospital and medical staff leadership, and should employ evidence-based strategies that best fit local needs and resources. An infectious diseases physician and clinical pharmacist with infectious diseases training are recommended as core members of the multidisciplinary team, although a hospitalist with interest (and perhaps additional training) in antimicrobial therapy may be able to fill the void. Program directors and core members should be compensated for their time. Principal proactive strategies--with evidence supporting their consideration--include prospective audits, with intervention and feedback, formulary restriction, and preauthorization. Other strategies include persistent one-on-one education, guidelines adapted to local needs, and informatics to support clinical decision making. Intervention goals are to prevent unnecessary antimicrobial starts, to streamline or de-escalate therapy early in its course, and to convert from parenteral to oral therapy, optimize dosing, and ensure the appropriate length of therapy. Most community hospitals, if sufficiently resourced, should be able to implement a successful antimicrobial stewardship program. Evidence suggests that good antimicrobial stewardship can lead to less overall and inappropriate antimicrobial use, lower drug-related costs, reductions in Clostridium difficile-associated disease, and, in some studies, less emergence of antimicrobial resistance.

Prevention of endemic healthcare-associated Clostridium difficile infection: reviewing the evidence

OBJECTIVES

Clostridium difficile is the most common infectious cause of healthcare-associated diarrhea. Because of the increasing incidence and severity of endemic C. difficile infection (CDI), interventions to prevent healthcare-associated CDI are essential. We undertook a systematic review of interventions to reduce healthcare-associated CDI.

METHODS

We searched multiple computerized databases, and manually searched for relevant articles to determine which interventions are useful in preventing CDI. Studies were required to be controlled in design and to report the incidence of endemic CDI as an outcome. Data on the patient population, intervention, study design, and outcomes were abstracted and reviewed using established criteria.

RESULTS

Few randomized controlled trials exist in the area of CDI prevention. The interventions with the greatest evidence for the prevention of CDI include antimicrobial stewardship, glove use, and disposable thermometers. Environmental decontamination also may decrease CDI rates, although the level of evidence is not as strong as for the other proven interventions. Treatment of asymptomatic carriage of C. difficile is not recommended. There is insufficient evidence to make a recommendation for or against the use of probiotics. In cases of known or suspected CDI, hand hygiene with soap and water is preferred over use of waterless alcohol hand rub. Many nonrandomized trials included in our analysis used multiple interventions concurrently, making the independent role of each preventive strategy difficult to determine. We chose to include only studies that focused on endemic CDI because studies of outbreaks have used multiple strategies, making it difficult to measure the relative efficacy of each strategy. Environmental disinfection and probiotics need to be studied further to evaluate their roles in the prevention of CDI. Although there have been no studies assessing the utility of isolation and cohorting for the prevention of endemic CDI specifically, it is a widely used intervention for containment of this and other similar multidrug-resistant pathogens.

CONCLUSIONS

Antimicrobial stewardship, glove use, hand hygiene, and disposable thermometers should be routinely used for the prevention of CDI. Environmental disinfection and probiotics should be studied further for their role in reducing CDI.

Empiric therapy for gram-negative pathogens in nosocomial and health care-associated pneumonia: starting with the end in mind

Nosocomial pneumonia is a major cause of morbidity and mortality for hospitalized patients. Antimicrobial resistance is increasing, creating a strain between ensuring the provision of adequate empiric therapy and slowing the development of antimicrobial resistance. Excessive antimicrobial therapy places patients are at greater risk of drug interactions, adverse events, and superinfections. Ways to maximize adequate empiric therapy include (1) categorizing each patient's risk of being infected with a multidrug-resistant pathogen and knowledge of local susceptibility patterns, (2) de-escalating antimicrobial therapy to decrease the rates of superinfections such as Clostridium difficile, and (3) limiting the duration of therapy to decrease the likelihood of adverse events, drug interactions, and antimicrobial resistance. Pharmacodynamically enhanced dosing regimens also have the potential to improve clinical outcomes and slow the development of antimicrobial resistance. Drugs whose killing is optimized by the percentage time above the minimum inhibitory concentration (MIC), such as beta-lactams, can be given by continuous or extended infusion to provide superior pharmacodynamic (PD) target attainment rates compared with traditional regimens. Drugs whose killing is optimized with a high-peak plasma concentration to MIC ratio (eg, aminoglycosides) should be administered once daily to maximize the likelihood of achieve optimal target attainment rates. Drugs whose killing is optimized by the ratio of the area under the curve (AUC) to MIC ratio (eg, fluoroquinolones) depend on the total daily dose as opposed to the dosing schedule or infusion time. Determining the optimal drug dosing schedules for obese patients remains critical because these patients have may have significantly increased volumes of distribution and clearance rates compared to normal weight patients. Optimizing the use of current antimicrobials is paramount to ensure quality treatment options are available, given the lack of gram-negative antimicrobials in the pipeline.

Healthcare costs of Staphylococcus aureus and Clostridium difficile infections in veterans: role of vitamin D deficiency

Clostridium difficile and staphylococcal infections are associated with increased morbidity, mortality and healthcare costs. Vitamin D deficiency may also contribute to increased healthcare costs. There is increasing evidence that vitamin D may have an antimicrobial role. We examined the relationship of serum 25(OH)D levels to staphylococcal and C. difficile infections to determine if vitamin D deficiency was associated with adverse outcomes. In the outpatient setting, vitamin D deficiency in patients with C. difficile and staphylococcal infections were associated with significantly increased total outpatients costs and fee-based consultation. Laboratory expenses had a trend towards higher costs in the vitamin D-deficient group but did not reach statistical significance. The differences were most clearly seen in the in-patient group with enhanced laboratory, pharmacy and radiology costs. These differences resulted in vitamin D-deficient patients with C. difficile or staphylococcal infections having costs more than five times higher than the non-deficient patients. The total length of hospital stay was four times greater in the vitamin D-deficient group. In addition, the total number of hospitalizations was also significantly greater in the vitamin D-deficient group. Surgery costs demonstrated a tendency to be higher in the vitamin D-deficient group but failed to reach statistical significance. Vitamin D deficiency is intimately linked to adverse health outcomes and costs in Veterans with staphylococcal and C. difficile infections in North East Tennessee. We recommend that vitamin D status be checked in patients with these infections and appropriate therapy be instituted to restore vitamin D level to normal in an expeditious manner.

Clostridium difficile infection in the intensive care unit

Clostridium difficile infection (CDI) is becoming more common worldwide. The morbidity and mortality associated with C difficile is also increasing at an alarming rate. Critically ill patients are at particularly high risk for CDI because of the prevalence of multiple risk factors in this patient population. Treatment of C difficile continues to be a difficult problem in patients with severe or recurrent disease. This article seeks to provide a broad understanding of CDI in the intensive care unit, with special emphasis on risk factor identification, treatment options, and disease prevention.

[Nosocomial infections: MRSA und CDAD as a challenge]

Inadequate antibiotic prescribing and poor adherence to infection control guidelines are the main reasons for the development and spread of methicillin-resistant Staphylococcus aureus (MRSA) and Clostridium difficile (CD), the most important cause of antibiotic-associated diarrhoea (AD) and colitis. Both CDAD and MRSA infection are associated with significant morbidity, excess mortality and substantial consumption of resources. Increases in the incidence of both infections have been observed in Germany and represent a challenge to clinicians, infection control practitioners, quality management teams und hospital administration. Prudent use of antibiotics, in particular critical prescribing of fluoroquinolones and cephalosporins, is an important component in programmes aiming at an effective prevention of MRSA and CDAD. Other similarly important components are minimization of pathogen transmission between patients and healthcare personnel by isolation and contact precautions, early detection of MRSA carriers and MRSA decolonization treatment. It must be ascertained that patients nursed in isolation rooms receive medical care of similar high quality as all other patients. Over the last years, there has been no major breakthrough in therapy and outcomes in both CDAD and MRSA infection. Close collaboration between hospitals, nursing homes and primary care institutions will be critical for better control of MRSA and CDAD.

Is there a future for probiotics in preventing Clostridium difficile-associated disease and treatment of recurrent episodes?

Due to morbidity, mortality, and high costs associated with eradicating Clostridium difficile once this organism causes colitis, this bacterium has been termed one of the most ecologically relevant microorganisms of the present day. Symptoms associated with C. difficile diarrhea often first present during or shortly after a course of antibiotic therapy. During the past 5 years, the virulence of this organism has increased. C. difficile-associated disease (CDAD) has reached epidemic proportions in some hospital settings, prompting Medicare to propose adding CDAD to the list of hospital-acquired conditions for which reimbursements may be cut. Thus, it is imperative that effective preventive strategies be implemented in hospitals to decrease CDAD infections. It is plausible that probiotic supplements may offer a safe and effective means of preventing both initial CDAD episodes as well as CDAD recurrences. This review critically examines the current literature in which probiotic supplements have been studied for efficacy in CDAD prevention. This analysis will guide practitioners in applying available probiotic data to CDAD clinical scenarios and will assist researchers in the appropriate design of future studies as examination continues into the role that probiotics may have in CDAD prevention.

Clostridium difficile infection in solid organ transplant recipients

PURPOSE OF REVIEW

To provide a general understanding of Clostridium difficile infection with a focus on recent publications that evaluate the disease in solid organ transplant recipients.

RECENT FINDINGS

The incidence of C. difficile infection is increasing worldwide. Epidemics due to a hypervirulent C. difficile strain are associated with an escalating severity of disease. New evidence further supports basing initial treatment choice on disease severity.

SUMMARY

C. difficile is a significant pathogen in solid organ transplant recipients. Multiple risk factors are found in this population that may result in more severe disease. A high index of suspicion is necessary for the early diagnosis and treatment of C. difficile infection in transplant recipients. Metronidazole and vancomycin show equivalent efficacy in the treatment for mild-to-moderate disease, but vancomycin has demonstrated superiority in the treatment of severe disease. Surgical intervention is also an important consideration in the treatment of solid organ transplant recipients with severe colitis. Rigorous infection control practices are essential for preventing the spread of C. difficile within the hospital environment.

Antibiotic use and other risk factors at hospital level for outbreaks with Clostridium difficile PCR ribotype 027

The first Dutch outbreak due to Clostridium difficile ribotype 027 was observed in mid-2005; by the end of that year, eight hospitals were affected. To study the relationship between hospital-wide antibiotic use and the incidence of 027-linked C. difficile-associated disease (CDAD) three study groups were made: group A, all eight hospitals with an 027-associated epidemic; group B, five of a total of six hospitals with occasional 027 cases, without an increase in CDAD; and group C, ten randomly selected hospitals with no reported 027 epidemics or isolated 027 cases. Quarterly data on CDAD incidences, hygiene measures and the use of fluoroquinolones, second- and third-generation cephalosporins, extended-spectrum penicillins, penicillins with beta-lactamase inhibitors, carbapenems, lincomycins and macrolides were collected for 2004 and 2005, and divided into pre-epidemic and epidemic periods. Using a multilevel Poisson regression analysis, CDAD incidence was linked to antibiotic use in the previous quarter and to certain hygiene measures. In the pre-epidemic period, the total use of the studied antibiotics was comparable between affected and unaffected hospitals. Higher use of second-generation cephalosporins, macrolides and all of the studied antibiotics were independently associated with a small increase in CDAD incidence [relative risk (95% confidence interval): 1.14 per increase of 100 defined daily doses per 10,000 bed days (1.06-1.23), 1.10 (1.01-1.19) and 1.02 (1.01-1.03), respectively]. However the effect was too small to predict which hospitals might be more prone to 027-associated outbreaks.

Recent advances in Clostridium difficile-associated disease

The main purpose of this article is to review recent developments in the management of acute and recurrent Clostridium difficile-associated disease, with consideration of existing and new antibiotic and non-antibiotic agents for treatment. Details of the current developmental stage of new agents are provided and the role of surgery in the management of severe disease is discussed. Infection control measures considered comprise prudent use of antimicrobials, prevention of cross-infection and surveillance. Other topics that are covered include the recent emergence of an epidemic hypervirulent strain, pathogenesis, clinical presentation and approaches to rapid diagnosis and assessment of the colonic disease.

Implications of the changing face of Clostridium difficile disease for health care practitioners

Recent reported outbreaks of Clostridium difficile-associated disease in Canada have changed the profile of C difficile infections. Historically, C difficile disease was thought of mainly as a nosocomial disease associated with broad-spectrum antibiotics, and the disease was usually not life threatening. The emergence of an epidemic strain, BI/NAP1/027, which produces a binary toxin in addition to the 2 classic C difficile toxins A and B and is resistant to some fluoroquinolones, was associated with large numbers of cases with high rates of mortality. Recently, C difficile has been reported more frequently in nonhospital-based settings, such as community-acquired cases. The C difficile disease is also being reported in populations once considered of low risk (children and young healthy women). In addition, poor response to metronidazole treatment is increasing. Faced with an increasing incidence of C difficile infections and the changing profile of patients who become infected, this paper will reexamine the current concepts on the epidemiology and treatment of C difficile-associated disease, present new hypotheses for risk factors, examine the role of spores in the transmission of C difficile, and provide recommendations that may enhance infection control practices.

Identification, Optimal Management, and Infection Control Measures for Clostridium difficile–Associated Disease in Long-Term Care

Residents of long-term care facilities are at an increased risk of exposure to Clostridium difficile and become more susceptible to infection after receiving antimicrobial therapy. An increasing number and more severe cases of C. difficile-associated disease (CDAD) have been reported over the last few years and have been linked to the emergence of a new, more virulent strain of C. difficile. These serious cases of disease have also been associated with a more atypical clinical presentation and have prompted the need for an improved means of early recognition and identification performed by the nursing staff. This article reviews the pathogenesis and risk factors for CDAD, changing epidemiology of CDAD, and characteristics of the newly identified strain. Also reviewed are the role of nursing in the identification of patients with CDAD; optimal management of CDAD; infection control strategies; and education of health care professionals, residents, and visitors in the long-term care setting.

Measurement of Adult Antibacterial Drug Use in 130 US Hospitals: Comparison of Defined Daily Dose and Days of Therapy

BACKGROUND

Hospitals are advised to measure antibiotic use and monitor its relationship to resistance. The World Health Organization's recommended metric is the defined daily dose (DDD). An alternative measure is the number of days of therapy (DOT). The purpose of this study was to contrast these measures.

METHODS

We measured the use of 50 antibacterial drugs that were administered to adults who were discharged from 130 US hospitals during 1 August 2002-31 July 2003.

RESULTS

Of 1,795,504 patients, 1,074,174 received at least 1 dose of an antibacterial drug (59.8%). The mean (+/- standard deviation) of total antibacterial drug use measured by the number of DDDs per 1000 patient-days and the number of DOTs per 1000 patient-days were not significantly different (792+/-147 and 776+/-120, respectively; P=.137), although the correlation was poor (r=0.603). For some individual drugs, such as levofloxacin and linezolid, there was no significant difference between DDDs per 1000 patient-days and DOTs per 1000 patient-days, because the administered daily dosage was nearly equivalent to the DDD. When the administered dosage exceeded the DDD, such as for ampicillin-sulbactam and cefepime, estimates of use based on DDDs per 1000 patient-days significantly exceeded those based on DOTs per 1000 patient-days (P<.001). When the administered dosage was less than the DDD, such as for piperacillin-tazobactam and ceftriaxone, estimates of use based on DDDs per 1000 patient-days were significantly lower than those based on DOTs per 1000 patient-days (P<.001).

CONCLUSION

The measurement of aggregate hospital antibiotic use by DDDs per 1000 patient-days and DOTs per 1000 patient-days is discordant for many frequently used antibacterial drugs, because the administered dose is dissimilar from the DDD recommended by the World Health Organization. DDD methods are useful for benchmarking purposes but cannot be used to make inferences about the number of DOTs or relative use for many antibacterial drugs.

Clostridium difficile-associated disease in Oregon: increasing incidence and hospital-level risk factors

BACKGROUND

The incidence of Clostridium difficile-associated disease (CDAD) appears to be increasing. Population-based estimates of disease have been limited, and analyses of hospital-level risk factors for CDAD are lacking. We sought to determine the incidence and trends of CDAD in Oregon and to identify hospital-level factors associated with increases in disease.

METHODS

We analyzed hospital discharge data to calculate the incidence and to describe trends of CDAD in Oregon from 1995 through 2002. We administered questionnaires to hospital laboratory directors, infection control practitioners, and pharmacists to determine the status of laboratory, infection control, and pharmacy policies over time.

RESULTS

The overall incidence of CDAD in Oregon was 3.5 case patients per 10,000 residents in 2002. Incidence increased from 1.4 to 3.3 cases per 1,000 hospital discharges from 1995 to 2002. Rates of disease increased most in hospitals with licensed bed capacity of more than 250 beds and more than 5 intensive care unit beds. Few laboratories, infection control practitioners, and pharmacists were able to identify changes in specific policies over the study period.

CONCLUSIONS

This is the first study to determine a statewide population-based incidence of CDAD. Incidence of CDAD in Oregon has more than doubled over the past decade; larger hospitals experienced the greatest increase in disease rates. We did not identify hospital-level policies that could explain the increase. A study of patients with CDAD at the hospitals with the largest increases is underway to further identify risk factors.