Clostridium difficile infection: update on diagnosis, epidemiology, and treatment strategies

Toxin genotypes, antibiotic resistance and their correlations in Clostridioides difficile isolated from hospitals in Xi'an, China

BACKGROUND

Clostridioides difficile is the main pathogen of antimicrobial-associated diarrhoea and health care facility-associated infectious diarrhoea. This study aimed to investigate the prevalence, toxin genotypes, and antibiotic resistance of C. difficile among hospitalized patients in Xi'an, China.

RESULTS

We isolated and cultured 156 strains of C. difficile, representing 12.67% of the 1231 inpatient stool samples collected. Among the isolates, tcdA + B + strains were predominant, accounting for 78.2% (122/156), followed by 27 tcdA-B + strains (27/156, 17.3%) and 6 binary toxin gene-positive strains. The positive rates of three regulatory genes, tcdC, tcdR, and tcdE, were 89.1% (139/156), 96.8% (151/156), and 100%, respectively. All isolates were sensitive to metronidazole, and the resistance rates to clindamycin and cephalosporins were also high. Six strains were found to be resistant to vancomycin.

CONCLUSION

Currently, the prevalence rate of C. difficile infection (CDI) in Xi'an is 12.67% (156/1231), with the major toxin genotype of the isolates being tcdA + tcdB + cdtA-/B-. Metronidazole and vancomycin were still effective drugs for the treatment of CDI, but we should pay attention to antibiotic management and epidemiological surveillance of CDI.

A multicentre analysis of Clostridium difficile in persons with Cystic Fibrosis demonstrates that carriage may be transient and highly variable with respect to strain and level

PURPOSE

Clostridium difficile has been reported to occur in the gastrointestinal tract of 50% of Cystic Fibrosis (CF) subjects, however, clinical C. difficile infection (CDI) is a rare occurrence in this cohort despite the presence of toxigenic and hypervirulent ribotypes. Here, we present the first longitudinal, multicentre analysis of C. difficile prevalence among adult CF subjects.

METHODOLOGY

Faecal samples were collected from adults with CF (selected based on confirmed Pseudomonas aeruginosa pulmonary colonisation) from Ireland, UK and Belgium as part of the CFMATTERS clinical research trial (grant No. 603038) and from non-CF controls. Faecal samples were collected on enrolment, at three monthly intervals, during pulmonary exacerbation and three months post exacerbation. C. difficile was isolated from faecal samples by ethanol shocking followed by culturing on cycloserine cefoxitin egg yolk agar. Isolates were characterised in terms of ribotype, toxin type and antibiotic susceptibility to antibiotics routinely used in the treatment of CDI (metronidazole and vancomycin) and those implicated in induction of CDI (ciprofloxacin and moxifloxacin).

RESULTS

Prevalence of C. difficile among CF subjects in the three sites was similar ranging from 47% to 50% at baseline, while the healthy control cohort had a carriage rate of 7.1%. Including subjects who were positive for C. difficile at any time point there was a higher carriage rate of 71.4%, 66.7% and 63.2% in Ireland, UK, and Belgium, respectively. Ribotyping of 80 isolates from 45 CF persons, over multiple time points revealed 23 distinct ribotypes with two ribotypes (046 and 078) shared by all centres. The proportion of toxigenic isolates varied across the sites, ranging from 66.7% in Ireland to 52.9% in Belgium and 100% in the UK. Antibiotic susceptibility rates to vancomycin, metronidazole, ciprofloxacin and moxifloxacin was 100%, 97.5%, 1.3% and 63.8%, respectively.

CONCLUSIONS

This study demonstrates the highest carriage rate of C. difficile to date in a CF cohort. Longitudinal data show that C. difficile can be a transient inhabitant of the CF gut, changing both in terms of strain and excretion rates.

Clostridium difficile in patients with nosocomial diarrhea, Northwest of Iran

Background: Clostridium difficile is known as a prevalent pathogen leading to infections ranging from mild diarrhea to severe disease and death. The aim of the present study was to evaluate the incidence of C. difficile from inpatients with nosocomial diarrhea hospitalized in different wards in the northwest region of Iran.

Methods: In this cross-sectional study, 485 diarrheal stool samples were collected from 384 patients referred from different wards of Imam Reza, Sina and Pediatric hospitals, Tabriz and transferred to the laboratory from 25 March 2015 till 1 March 2018. Immuno-chromatographicassay for detection of toxins A and B of C. difficile was used for identification.

Results: Clostridium difficile was isolated from 24 (4.7%) out of 485 samples. Fifteen patients(62.5%) were males and 9 were females (37.5%). Twelve positive patients were from the gastrointestinal ward (50%), 5 patients (20.8%) from surgery ward, 3 patients from infectious disease ward (12.5%), 3 patients from rheumatology ward (12.5%) and 1 patient (4.1%) were collected from neurology ward. 95.3% of diarrhea samples had no signs from toxin A and B.

Conclusion: These results indicate most of infected patients were from the gastrointestinaland surgery wards which show a different pattern of infection compared to previous studies.The neurology department had the lowest rate of infection. C. difficile is a health threat afterantibiotic consumption and for health promotion, developing strategies for less antibioticconsumption and preventing these emerging infections is critical. The low rate of this infection shows improvement in knowledge and effect of stewardships in physicians.

Direct cost of health care for individuals with community associated Clostridium difficile infections: A population-based cohort study

Background

Even though the incidence of community-acquired Clostridium difficile infection (CDI) is reported to be increasing, few studies have reported on the healthcare costs of community-acquired CDI. We estimated cost of care for individuals with community-associated CDI and compared with that for matched controls without CDI in the time period of six months before to one year after CDI.

Methods

All individuals in the province of Manitoba, diagnosed with CDI between July 2005 and March 2015 were matched up to 4 individuals without CDI. Health care utilization and direct costs resulting from hospitalizations, physician reimbursement claims and prescriptions were determined from the population based provincial databases. Quantile regressions were performed to determine predictors of cost of individuals with community associated CDI.

Results

Of all CDIs, 30–40% in each period of the study had community-associated CDI; of which 12% were recurrent CDIs. The incremental median and 90^th percentile cost of care for individuals with community-associated CDI was $800 and $16,000 respectively in the six months after CDI diagnosis. After adjustment for age, co-morbidities, sex, socioeconomic status and magnitude of health care utilization prior to CDI, the median incremental cost for recurrent CDI was $1,812 and that for a subsequent episode of CDI was $3,139 compared to those with a single community-associated CDI episode. The median cost for a prescription of Vancomycin was $316 (IQR 209–489).

Conclusions

Health care costs of an episode of community-associated CDI have been much more than the cost of antibiotic treatment. Our study provides population-based data for formal cost effectiveness analysis for use of newer treatments for community-associated CDI.

Spatial clusters of Clostridium difficile infection and an association with neighbourhood socio-economic disadvantage in the Australian Capital Territory, 2004-2014

BACKGROUND

In Australia, rates of Clostridium difficile infection (CDI) in all States and Territories have increased significantly since mid-2011, with rates of infection increasing faster in the community setting than within hospitals. Knowledge about the risk factors for CDI is essential to determine the risk of community outbreaks of CDI and to design interventions that reduce those risks.

METHODS

We examine the role of neighbourhood socio-economic disadvantage, demography and testing practices on spatial patterns in CDI incidence in the Australian Capital Territory (ACT). Data on all tests conducted for CDI, including postcode of residence, were obtained from January 2004-December 2014. Distribution of age groups and the neighbourhood Index of Relative Socio-economic Advantage Disadvantage (IRSAD) were obtained from the Australian Bureau of Statistics 2011 National Census data. A Bayesian spatial conditional autoregressive model was fitted at the postcode level to quantify the relationship between CDI and socio-demographic factors. To identify CDI hotspots, exceedance probabilities were set at a threshold of twice the estimated relative risk.

RESULTS

After controlling for spatial patterns in testing practices, area-level socio-economic advantage (IRSAD) (RR = 0.74, 95% CI 0.57, 0.94) was inversely associated with CDI. Three postcodes had a high probability (0.8-1.0) of excess risk of diagnosed CDI.

CONCLUSION

We demonstrate geographic variations in CDI in the ACT with a positive association of CDI with neighbourhood socioeconomic disadvantage and identify areas with a high probability of elevated risk compared with surrounding communities. These findings provide further evidence to inform a targeted response to reduce CDI risk.

The Impact of Bariatric Surgery on Short Term Risk of Clostridium Difficile Admissions

BACKGROUND AND AIMS

Clostridium difficile infection (CDI) is major health care concern with reports linking it to obesity. Our aim was to investigate the little known impact of the two most common bariatric surgeries, Roux-en-Y gastric bypass (RYGB) and vertical sleeve gastrectomy (VSG), on risk of CDI admissions.

METHODS

This is a retrospective cohort study using the 2013 Nationwide Readmission Database. We examined inpatient CDI rates within 120 days after RYGB (n = 40,059) and VSG (n = 45,394). In a time to event analysis we also evaluated inpatient CDI rates up to 11 months post-surgery. We chose morbidly obese patients that underwent non-emergent ventral hernia repair (VHR) as additional surgical controls (n = 9673).

RESULT

CDI rates were higher after RYGB than VSG in the first 30 days (odds ratio [OR] = 2.10; 95% confidence interval [CI], 1.05-4.20) with a similar but nonsignificant trend within 31-120 days. CDI rates were also higher after RYGB compared to VHR controls within 31-120 days after surgery (OR = 3.22, 95%CI: 1.31, 7.88, p = 0.01). In a time to event analysis with up to 11 months follow up, RYGB led to higher CDI compared to VSG (hazard ratio [HR] = 1.87; 95% CI, 1.12-3.13) with a trend towards higher CDI compared to VHR (HR = 1.95; 95% CI, 0.94-4.06). Similar CDI rates occurred after VSG vs VHR.

CONCLUSIONS

RYGB may increase the risk of CDI hospitalization when compared to VSG and VHR controls. This data suggest VSG may be a better bariatric choice when post-surgical CDI risk is a concern.

2019 update of the WSES guidelines for management of Clostridioides (Clostridium) difficile infection in surgical patients

In the last three decades, Clostridium difficile infection (CDI) has increased in incidence and severity in many countries worldwide. The increase in CDI incidence has been particularly apparent among surgical patients. Therefore, prevention of CDI and optimization of management in the surgical patient are paramount. An international multidisciplinary panel of experts from the World Society of Emergency Surgery (WSES) updated its guidelines for management of CDI in surgical patients according to the most recent available literature. The update includes recent changes introduced in the management of this infection.

Clostridium difficile-associated Diarrhea in Developing Countries: A Systematic Review and Meta-Analysis

Introduction

The prevalence of Clostridium difficile infection is rapidly increasing worldwide, but prevalence is difficult to estimate in developing countries where awareness, diagnostic resources, and surveillance protocols are limited. As diarrhea is the hallmark symptom, we conducted a systematic review and meta-analysis to determine the prevalence and incidence of C. difficile infection in patients in these regions who presented with diarrhea.

Methods

We conducted a systematic literature search of MEDLINE/PubMed, Scopus, and Latin-American and Caribbean Health Sciences Literature databases to identify and analyze data from recent studies providing prevalence or incidence rates of C. difficile-associated diarrhea in developing countries within four regions: Africa–Middle East, developing Asia, Latin America, and China. Our objectives were to determine the current prevalence and incidence density rates of first episodes of C. difficile-associated diarrhea in developing countries.

Results

Within the regions included in our analysis, prevalence of C. difficile infection in patients with diarrhea was 15% (95% CI 13–17%) (including community and hospitalized patients), with no significant difference across regions. The incidence of C. difficile infection in 17 studies including this information was 8.5 per 10,000 patient-days (95% CI 5.83–12.46). Prevalence was significantly higher in hospitalized patients versus community patients (p  = 0.0227).

Conclusion

Our prevalence estimate of 15% is concerning; however, low awareness and inconsistent diagnostic and surveillance protocols suggest this is markedly underestimated. Enhanced awareness and management of C. difficile infection in patients with diarrhea, along with improvements in infection control and surveillance practices, should be implemented to reduce prevalence of C. difficile-associated diarrhea in developing countries.

Funding

Pfizer Inc.

Electronic supplementary material

The online version of this article (10.1007/s40121-019-0231-8) contains supplementary material, which is available to authorized users.

The Type of Bariatric Surgery Impacts the Risk of Acute Pancreatitis: A Nationwide Study

Objective

We investigated whether vertical sleeve gastrectomy (VSG) and Roux-en-Y gastric bypass surgery (RYGB) have a differential impact on post-operative risk of acute pancreatitis (AP).

Methods

This retrospective study uses the 2012–2014 National Readmission Database. We compared morbidly obese patients who underwent VSG (n = 205,251), RYGB (n = 169,973), and hernia repair (HR) control (n = 16,845). Our main outcome was rates of AP within 6 months post- vs. 6 months pre-surgery in VSG, RYGB, and HR. We also investigated risk factors and outcomes of AP after bariatric surgery.

Results

The rates of AP increased post- vs. pre-VSG (0.21% vs. 0.04%; adjusted odds ratio [aOR] = 5.16, P < 0.05) and RYGB (0.17% vs. 0.07%; aOR = 2.26, P < 0.05) but not post-HR. VSG was associated with a significantly greater increase in AP risk compared to RYGB (aOR = 2.28; 95% CI: 1.10, 4.73). Furthermore, when compared to HR controls, only VSG was associated with a higher AP risk (aOR = 7.58; 95% CI: 2.09, 27.58). Developing AP within 6 months following bariatric surgery was mainly associated with younger age (18–29 years old: aOR = 3.76 for VSG and aOR: 6.40 for RYGB, P < 0.05) and gallstones (aOR = 85.1 for VSG and aOR = 46 for RYGB, P < 0.05). No patients developed “severe AP” following bariatric surgery.

Conclusions

More patients develop AP within 6 months after VSG compared to RYGB and controls. This risk is highest for younger patients and those with gallstones. Prospective studies examining mechanisms and prevention are warranted.

Molecular epidemiology and antimicrobial susceptibility of human Clostridium difficile isolates from a single institution in Northern China

Because the epidemiology of Clostridium difficile infection (CDI) is region-specific, the present study was undertaken to examine the epidemiology of C difficile outbreaks in Beijing, China.Eighty nonduplicate isolates were collected from March, 2016 to December, 2016. The molecular type and phylogenetic analysis were evaluated by multilocus sequence typing (MLST). The minimum inhibitory concentrations (MICs) for 11 antibiotics and the resistance mechanisms were investigated.Sixty-five toxigenic strains (81.25%), including 22 tcdABCDT strains (27.5%) and 43 tcdABCDT strains (53.75%), and also 15 nontoxigenic strains (tcdABCDT; 18.75%) were detected. MLST identified 21 different sequence types (STs), including 2 novel types (ST409 and ST416). All isolates were susceptible to metronidazole, vancomycin, fidaxomicin, piperacillin/tazobactam, and meropenem, and all were effectively inhibited by emodin (MICs 4-8 μg/mL). The resistance rates to rifaximin, ceftriaxone, clindamycin, erythromycin, and ciprofloxacin were 8.75%, 51.25%, 96.25%, 81.25%, and 96.25%, respectively; 81.25% (65/80) of isolates were multidrug-resistant. Amino acid mutations in GyrA and/or GyrB conferred quinolone resistance. One novel amino acid substitution, F86Y in GyrA, was found in 1 CIP-intermediate strain. The erm(B) gene played a key role in mediating macrolide-lincosamide-streptogramin B (MLSB) resistance. Erm(G) was also found in erm(B)-negative strains that were resistant to both erythromycin and clindamycin. RpoB mutations were associated with rifampin resistance, and 2 new amino mutations were identified in 1 intermediate strain (E573A and E603N).Regional diversity and gene heterogeneity exist in both the ST type and resistant patterns of clinical C difficile isolates in Northern China.

Clostridium difficile causing pediatric infections: New findings from a hospital-based study in Italy

Recent studies support a change of Clostridium difficile infections (CDIs) epidemiology in pediatric patients. Since limited information is available about C. difficile in this population, we investigated the epidemiology of CDI in a large pediatric hospital that acts as reference centre in Italy and analyzed C. difficile isolates to identify the prevalent PCR-ribotypes (RTs), the binary toxin (CDT)-positive strains and the antibiotic susceptibility patterns. The CDI incidence was 6.6 cases/1000 admissions and the majority (92%) of CDI were healthcare-associated (47% occurred in the Hematology-Oncology and in the Gastroenterology units). Most of symptomatic children <3 years with a positive culture for C. difficile were negative for other gastrointestinal pathogens, supporting C. difficile as cause of disease in these patients, including those showing recurrences. Strains RT020 (16%) and RT014 (14%) were identified as the main cause of infection, while RT356/607 and RT018, predominant in Italian adult patients, were absent (RT356/607) or rarely found (RT018) among children. CDT-positive strains represented the 20% of the total number of isolates analyzed. In particular, two emerging types, RT033 and RT442, were recognized as Toxin A-/Toxin B-/CDT+. Resistance to antibiotics characterized almost 50% of the toxigenic isolates analyzed in this study and, in particular, 20% of them were multidrug resistant (MDR). The emergence and circulation of strains with peculiar toxins profiles and/or MDR strongly highlight the necessity of a rapid CDI diagnosis, a careful monitoring of C. difficile in pediatric patients and a more strict control of antibiotics usage in the Italian pediatric hospitals.

Higher Incidence of Clostridium difficile Infection Among Individuals With Inflammatory Bowel Disease

BACKGROUND & AIMS

Studies of Clostridium difficile infections (CDIs) among individuals with inflammatory bowel disease (IBD) have used data from single centers or CDI administrative data codes of limited diagnostic accuracy. We determined the incidence, risk factors, and outcomes after CDI in a population-based cohort of patients with IBD and laboratory confirmation diagnoses of CDI.

METHODS

We searched the University of Manitoba IBD Epidemiology Database and Manitoba Health CDI databases to identify individuals with CDI, with or without IBD, from July 1, 2005 through March 31, 2014. Time trends of incidence were assessed using joinpoint regression. Multivariable Cox regression analyses were performed to assess differences in CDI incidence rates and mortality after CDI between individuals with and without IBD. Conditional logistic regression was performed to determine predictors of CDI among individuals with IBD.

RESULTS

Individuals with IBD had a 4.8-fold increase in risk of CDI than individuals without IBD; we found no difference between individuals with ulcerative colitis vs Crohn's disease. There was no increase in CDI incidence over the study time period in either group. Among individuals with IBD, exposure to corticosteroids, infliximab or adalimumab, metronidazole, hospitalizations, higher ambulatory care visits, shorter duration of IBD, and higher comorbidities were associated with an increased risk of CDI. Although CDI increased mortality among individuals with and without IBD, there was lower mortality after CDI among individuals with IBD than without IBD (hazard ratio, 0.65; 95% confidence interval, 0.44-0.96).

CONCLUSIONS

CDI incidence is no longer increasing among individuals with IBD. We identified unique risk factors for CDI in patients with IBD. CDI is associated with a greater increase in mortality among individuals without IBD than with IBD.

Assessing the effect of patient screening and isolation on curtailing Clostridium difficile infection in hospital settings

BACKGROUND

Patient screening at the time of hospital admission is not recommended as a routine practice, but may be an important strategy for containment of Clostridium difficile infection (CDI) in hospital settings. We sought to investigate the effect of patient screening in the presence of asymptomatic carriers and in the context of imperfect patient isolation.

METHODS

We developed and parameterized a stochastic simulation model for the transmission dynamics of CDI in a hospital ward.

RESULTS

We found that the transmission of CDI in the hospital, either through asymptomatic carriers or as a results of ineffective implementation of infection control practices, at the time of hospital admission. The results show that, for a sufficiently high reproduction number of CDI, the disease can persist within a hospital setting in the presence of in-ward transmission, even when there are no asymptomatically colonized patients at the time of hospital admission.

CONCLUSIONS

Our findings have significant public health and clinical implications, especially in light of the emergence and community spread of hypervirulent CDI strains with enhanced transmission rates and toxin production. Rapid detection of colonized patients remains an important component of CDI control, especially in the context of asymptomatic transmission. Screening of in-hospital patients with potential exposure to colonized patients or contaminated environment and equipment can help reduce the rates of silent transmission of CDI through asymptomatic carriers.

Hospital discharge abstracts have limited accuracy in identifying occurrence of Clostridium difficile infections among hospitalized individuals with inflammatory bowel disease: A population-based study

BACKGROUND

Hospital discharge databases are used to study the epidemiology of Clostridium difficile infections (CDI) among hospitalized patients with inflammatory bowel disease (IBD). CDI in IBD is increasingly important and accurately estimating its occurrence is critical in understanding its comorbidity. There are limited data on the reliability of the International Classification of Diseases 10th revision (ICD-10) (now widely used in North America) CDI code in determining occurrence of CDI among hospitalized patients. We compared the performance of ICD-10 CDI coding to laboratory confirmed CDI diagnoses.

METHODS

The University of Manitoba IBD Epidemiology Database was used to identify individuals with and without IBD discharged with CDI diagnoses between 07/01/2005 and 3/31/2014. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of ICD-10 CDI code was compared to laboratory CDI diagnoses recorded in a province wide CDI dataset. Multivariable logistic regression models were performed to test the predictors of diagnostic inaccuracy of ICD-10 CDI code.

RESULTS

There were 273 episodes of laboratory confirmed CDI (hospitalized and non-hospitalized) among 7396 individuals with IBD and 536 among 66,297 matched controls. The sensitivity, specificity, PPV and NPV of ICD-10 CDI code in discharge abstracts was 72.8%, 99.6%, 64.1% and 99.7% among those with IBD and 70.8%, 99.9%, 79.0% and 99.9% among those without IBD. Predictors of diagnostic inaccuracy included IBD, older age, increased co-morbidity and earlier years of hospitalization.

CONCLUSIONS

Identification of CDI using ICD-10 CDI code in hospital discharge abstracts may not identify up to 30% of CDI cases, with worse performance among those with IBD.

Occurrence of Clostridium difficile ribotype 027 in hospitals of Silesia, Poland

Clostridium difficile is an important healthcare-associated pathogen, responsible for a broad spectrum of diarrheal diseases. The aim of this prospective study was to determine the occurrence of C. difficile infection (CDI), to characterize cultured C. difficile strains and to investigate the association of fecal lactoferrin with CDI. Between January 2013 and June 2014, 148 stool samples were obtained from adult diarrheal patients (C. difficile as a suspected pathogen) hospitalized in different healthcare facilities of 15 Silesian hospitals. Out of 134 isolated C. difficile strains, 108 were ribotyped: 82.4% belonged to Type 027, 2.8% to Type 176, 2.8% to Type 014, 1.9% to Type 010 and 0.9% to Types 001, 018, 020 and 046 each. In total, 6.5% non-typable strains were identified. All Type 027 isolates contained both toxin genes tcdA & tcdB, and binary toxin genes (cdtA &cdtB). Susceptibility testing revealed that all Type 027 isolates were sensitive to metronidazole and vancomycin and resistant to moxifloxacin, ciprofloxacin, imipenem and erythromycin. Of 89 Type 027 strains, 16 had a ermB (688 bp) gene coinciding with high levels of erythromycin resistance (MIC >256 μg/mL). Of 16 ermB positive strains, 14 demonstrated also high level of resistance to clindamycin (>256 μg/mL). A significant difference (p = 0.004) in lactoferrin level was found between C. difficile toxin-positive (n = 123; median 185.9 μg/mL; IQR 238.8) and toxin-negative (n = 25; median 22.4 μg/mL; IQR 141.7) fecal samples. Stool samples from n = 89 patients with CDI caused by Type 027 demonstrated significantly higher (p = 0.03) lactoferrin level (median 173.0 μg/mL; IQR 237.3) than from patients with CDI caused by other ribotypes and non-typable C. difficile strains (median 189.4 μg/mL; IQR 190.8).

Probiotics are effective at preventing Clostridium difficile-associated diarrhea: a systematic review and meta-analysis

INTRODUCTION

Clostridium difficile infection (CDI) is the leading cause of antibiotic-associated diarrhea. CDI has increased in incidence and severity over the past decade, and is a growing worldwide health problem associated with substantial health care costs and significant morbidity and mortality. This meta-analysis examines the impact of probiotics on the incidence of Clostridium difficile-associated diarrhea (CDAD) among children and adults, in both hospital and outpatient settings.

METHODS

A comprehensive literature search of all published randomized control trials (RCTs) assessing the use of probiotics in the prevention of CDAD in patients receiving antibiotic therapy was conducted, and the incidence of CDAD was analyzed.

RESULTS

Twenty-six RCTs involving 7,957 patients were analyzed. Probiotic use significantly reduced the risk of developing CDAD by 60.5% (relative risk [RR] =0.395; 95% confidence interval [CI], 0.294-0.531; P<0.001). Probiotics proved beneficial in both adults and children (59.5% and 65.9% reduction), especially among hospitalized patients. Lactobacillus, Saccharomyces, and a mixture of probiotics were all beneficial in reducing the risk of developing CDAD (63.7%, 58.5%, and 58.2% reduction).

CONCLUSION

Probiotic supplementation is associated with a significant reduction in the risk of developing CDAD in patients receiving antibiotics. Additional studies are required to determine the optimal dose and strain of probiotic.

Recent advances in the understanding of antibiotic resistance in Clostridium difficile infection

Clostridium difficile epidemiology has changed in recent years, with the emergence of highly virulent types associated with severe infections, high rates of recurrences and mortality. Antibiotic resistance plays an important role in driving these epidemiological changes and the emergence of new types. While clindamycin resistance was driving historical endemic types, new types are associated with resistance to fluoroquinolones. Furthermore, resistance to multiple antibiotics is a common feature of the newly emergent strains and, in general, of many epidemic isolates. A reduced susceptibility to antibiotics used for C. difficile infection (CDI) treatment, in particular to metronidazole, has recently been described in several studies. Furthermore, an increased number of strains show resistance to rifamycins, used for the treatment of relapsing CDI. Several mechanisms of resistance have been identified in C. difficile, including acquisition of genetic elements and alterations of the antibiotic target sites. The C. difficile genome contains a plethora of mobile genetic elements, many of them involved in antibiotic resistance. Transfer of genetic elements among C. difficile strains or between C. difficile and other bacterial species can occur through different mechanisms that facilitate their spread. Investigations of the fitness cost in C. difficile indicate that both genetic elements and mutations in the molecular targets of antibiotics can be maintained regardless of the burden imposed on fitness, suggesting that resistances may persist in the C. difficile population also in absence of antibiotic selective pressure. The rapid evolution of antibiotic resistance and its composite nature complicate strategies in the treatment and prevention of CDI. The rapid identification of new phenotypic and genotypic traits, the implementation of effective antimicrobial stewardship and infection control programs, and the development of alternative therapies are needed to prevent and contain the spread of resistance and to ensure an efficacious therapy for CDI.

Periodontal-disease-associated biofilm: A reservoir for pathogens of medical importance

The ecological diversity of the periodontal microenvironment may provide suitable conditions for the colonization of species not usually considered members of the oral microbiota. In this investigation, we aimed to determine the prevalence and levels of pathogenic species of medical relevance in the microbiota of individuals with distinct periodontal clinical status. Subgingival biofilm was obtained from patients with periodontal health (H, n = 81), gingivitis (G, n = 55), generalized aggressive (AgP, n = 36) or chronic periodontitis (CP, n = 98), and analyzed for 39 microbial taxa using a checkerboard DNA-DNA hybridization technique. Microbial differences among groups, as well as associations between clinical and microbiological parameters were sought by non-parametric and univariate correlation tests. Neisseria spp., Peptostreptococus anaerobius, Candida albicans, enterobacteria, Pseudomonas aeruginosa, Eubacterium saphenum, Clostridium difficile and Olsenella uli were detected in high mean prevalence and counts in the subgingival microbiota of the study population. Species that were more related to periodontal inflammation and tissue destruction at the patient and site levels included enterobacteria, C. albicans, Neisseria spp., P. aeruginosa, O. uli, Hafnia alvei, Serratia marcescens and Filifactor alocis (p < 0.05). In contrast, Fusobacterium necrophorum, Lactobacillus acidophilus, Staphylococcus aureus and Streptococcus pneumoniae were associated with periodontal health (p < 0.05). Pathogenic species of medical importance may be detected in high prevalence and levels in the periodontal microbiota. Regardless of their role in periodontal health or disease, the periodontal biofilm may be a source for dissemination and development of systemic infections by these pathogenic microorganisms.

WSES guidelines for management of Clostridium difficile infection in surgical patients

In the last two decades there have been dramatic changes in the epidemiology of Clostridium difficile infection (CDI), with increases in incidence and severity of disease in many countries worldwide. The incidence of CDI has also increased in surgical patients. Optimization of management of C difficile, has therefore become increasingly urgent. An international multidisciplinary panel of experts prepared evidenced-based World Society of Emergency Surgery (WSES) guidelines for management of CDI in surgical patients.

Human microbiome: From the bathroom to the bedside

The human gut contains trillions of bacteria, the major phylae of which include Bacteroidetes, Firmicutes, Actinobacteria and Proteobacteria. Fecal microbial transplantation (FMT) has been known of for many years but only recently has been subjected to rigorous examination. We review the evidence regarding FMT for recurrent Clostridium difficile infection which has resulted in it being an approved treatment. In addition there is some evidence for its use in both irritable bowel syndrome and inflammatory bowel disease. Further research is needed in order to define the indications for FMT and the most appropriate method of administration.

Evaluating the Patient with Left Lower Quadrant Abdominal Pain

Left lower quadrant pain is a frequent indication for imaging in the emergency department. Most causes of pain originate from the colon, including diverticulitis, colitis, fecal impaction, and epiploic appendagitis. Left-sided urolithiasis and spontaneous hemorrhage in the retroperitoneum or rectus sheath are additional causes of pain. Computed tomography is the preferred imaging modality in the emergent setting for all of these pathologic conditions. Gynecologic, testicular, and neoplastic pathology may also cause left lower quadrant pain but are not discussed in this article.

C. difficile Infection: Changing Epidemiology and Management Paradigms

The incidence of Clostridium difficile infection (CDI) has been rising in hospitals, long-term care facilities, and within the community. Cases have been more severe with more complications, deaths, and higher healthcare-associated costs. With the emergence of a hypervirulent strain of C. difficile and the increasing prevalence of community-acquired CDI among healthy patients without traditional risk factors, the epidemiology of C. difficile has been evolving. This changing epidemiology requires a change in management. Taking into account new risk factors for CDI and growing subpopulations of affected individuals, diagnostic, treatment, and prevention approaches need to be adjusted.

Vancomycin Enemas as Adjunctive Therapy for Clostridium difficile Infection

Background

For severe, complicated Clostridium difficile infection (CDI), concomitant treatment with IV metronidazole and oral vancomycin is usually prescribed. Sometimes vancomycin per rectum (VPR) is added to increase colonic drug delivery. Our purpose was to examine clinical outcomes of patients with CDI treated with VPR and compare results to a matched control group.

Methods

This was a retrospective case-control study in a setting of tertiary-care ICU on diarrhea patients with a positive toxin test for C. difficile. We identified all ICU patients prescribed VPR from January 2003 to December 2013. The dose of VPR mixed in 100 cc of tap water ranged from 125 to 250 mg Q 6 - 8 hours. All patients had diarrhea and a positive test for C. difficile toxin. Included patients received ≥ 4 doses of VPR. The primary outcome was the combined endpoint of colon surgery or death. We matched VPR cases 1:2 with CDI controls that had identical APACHE II scores.

Results

We identified 24 CDI patients who received VPR and met inclusion criteria: 11 male, mean age 61.8 ± 15.9 years. All patients received concomitant CDI therapy. Four patients (16.7%) required colectomy, and overall mortality was 45.8%. For the 48 controls, need for surgery was identical (16.7%; P = 1.00). The mortality rate also did not differ (41.7%; P = 0.74). For the combined outcome of surgery or death, the rate was 45.8% for the controls and 50.0% for the VPR group (P = 0.73).

Conclusion

In a case-control study, the use of VPR was not demonstrated to reduce the need for colectomy or decrease mortality. Based on our modest sample size and failure to show efficacy, we cannot strongly advocate for the use of VPR.

Lower incidence of hypo-magnesemia in surgical intensive care unit patients in 2011 versus 2001

Background

Hypo-magnesemia is described to occur in as many as 65% of intensive care unit (ICU) patients. Magnesium (Mg) is a cofactor in over 300 enzymatic reactions involving energy metabolism, protein, and nucleic acid synthesis. The membrane pump that creates the electrical gradient across the cell membrane is dependent on Mg, and it is important in the activity of electrically excitable tissues. Since Mg regulates the movement of calcium in smooth muscle cells, it is also important in peripheral vascular tone and blood pressure. Studies have linked hypo-magnesemia to multiple chronic diseases and to a higher mortality rate.

Methods

To explore trends within our own tertiary care surgical ICU, we sampled our patients’ laboratory records in 2001 and in 2011. Hypo-magnesemia in our ICU is defined as an Mg less than 2.0 mg/dL.

Results

This retrospective review of all SICU patients from October to December revealed that there was a significant increase (P < 0.01) in the patients with their serum Mg level measured between 2001 (89%) and 2011 (95%). There was a significant decrease (P < 0.001) in patients with hypomagnesemia (< 2 mg/dL) between 2001 (47.5%) and 2011 (33.0%). On the other hand, there was a significant increase (P < 0.001) in patients with normal serum Mg level (> 2 mg/dL) between 2001 (52.5%) and 2011 (67.0%).

Conclusions

There was not only more monitoring of Mg in 2011, but a lower incidence of hypo-Mg compared to 2001. Possible explanations include changing patterns of antibiotic and diuretic use, less amphotericin use, more frequent laboratory surveillance, and better trained ICU practitioners.