Differential risk of Clostridium difficile infection with proton pump inhibitor use by level of antibiotic exposure

The combined effect of systemic antibiotics and proton pump inhibitors on Clostridioides difficile infection and recurrence

BACKGROUND

Antibiotics and proton pump inhibitors (PPI) are recognized risk factors for acquisition and recurrence of Clostridioides difficile infection (CDI), yet combined effects remain unclear.

OBJECTIVES

To assess the short- and long-term effects of antibiotics and PPIs on CDI risk and recurrence.

METHODS

Population-based study including all 43 152 patients diagnosed with CDI in Sweden (2006-2019), and 355 172 matched population controls without CDI. The impact of antibiotics and PPIs on CDI risk and recurrence was explored for recent (0-30 days) and preceding (31-180 days) use prior to their first CDI diagnosis, using multivariable conditional logistic regression presented as odds ratios (ORs) and 95% confidence interval, adjusted for demographics, comorbidities and other drugs.

RESULTS

Compared to controls, the combined effect of recent PPIs and antibiotics [ORAB+PPI = 17.51 (17.48-17.53)] on CDI risk was stronger than the individual effects [ORAB = 15.37 (14.83-15.93); ORPPI = 2.65 (2.54-2.76)]. Results were less pronounced for exposure during the preceding months. Dose-response analyses showed increasing exposure correlated with CDI risk [recent use: ORAB = 6.32 (6.15-6.49); ORPPI = 1.65 (1.62-1.68) per prescription increase].Compared to individuals without recurrence (rCDI), recent [ORAB = 1.30 (1.23-1.38)] and preceding [ORAB = 1.23 (1.16-1.31); ORPPI = 1.12 (1.03-1.21)] use also affected the risk of recurrence yet without significant interaction between both. Recent macrolides/lincosamides/streptogramins; other antibacterials including nitroimidazole derivates; non-penicillin beta lactams and quinolones showed the strongest association with CDI risk and recurrence, particularly for recent use. PPI use, both recent and preceding, further increased the CDI risk associated with almost all antibiotic classes.

CONCLUSION

Recent and less recent use of PPIs and systemic antibiotics was associated with an increased risk of CDI, particularly in combination.

Healthcare facility-onset, healthcare facility-associated Clostridioides difficile infection in Veterans with spinal cord injury and disorder

Objective: To describe the burden and risk of healthcare facility-onset, healthcare facility-associated (HO-HCFA) Clostridioides difficile infection (CDI) in Veterans with spinal cord injury and disorder (SCI/D). Design: Retrospective, longitudinal cohort study from October 1, 2001-September 30, 2010. Setting: Ninety-four acute care Veterans Affairs facilities. Participants: Patients with SCI/D. Outcomes: Incidence rate of HO-HCFA CDI. Methods: Rates of CDI were determined, and crude unadjusted incidence rate ratios (IRRs) and 95% confidence intervals (CIs) were calculated. Multivariable Poisson random-effects regression analyses were used to assess factors independently associated with the rate of CDI. Results: 1,409 cases of HO-HCFA CDI were identified. CDI rates in 2002 were 13.9/10,000 person-days and decreased to 5.5/10,000 person-days by 2010. Multivariable regression analyses found that antibiotic (IRR = 18.79, 95% CI 14.09-25.07) and proton-pump inhibitor (PPI) or H2 blocker use (IRR = 7.71, 95% CI 5.47-10.86) were both independently associated with HO-HCFA CDI. Exposure to both medications demonstrated a synergistic risk (IRR = 37.55, 95% CI 28.39-49.67). Older age, Northeast region, and invasive respiratory procedure in the prior 30 days were also independent risk factors, while longer SCI duration and care at a SCI center were protective. Conclusion: Although decreasing, CDI rates in patients with SCI/D remain high. Targeted antimicrobial stewardship and pharmacy interventions that reduce antibiotic and PPI/H2 blocker use could have profound benefits in decreasing HO-HCFA CDI in this high-risk population.

Clostridium difficile Infection: An Epidemiology Update

Clostridium (reclassified as " Clostridioides ") difficile infection (CDI) is a healthcare-associated infection and significant source of potentially preventable morbidity, recurrence, and death, particularly among hospitalized older adults. Additional risk factors include antibiotic use and severe underlying illness. The increasing prevalence of community-associated CDI is gaining recognition as a novel source of morbidity in previously healthy patients. Even after recovery from initial infection, patients remain at risk for recurrence or reinfection with a new strain. Some pharmaco-epidemiologic studies have suggested an increased risk associated with proton pump inhibitors and protective effect from statins, but these findings have not been uniformly reproduced in all studies. Certain ribotypes of C. difficile , including the BI/NAP1/027, 106, and 018, are associated with increased antibiotic resistance and potential for higher morbidity and mortality. CDI remains a high-morbidity healthcare-associated infection, and better understanding of ribotypes and medication risk factors could help to target treatment, particularly for patients with high recurrence risk.

Deprescribing Proton Pump Inhibitors in an Academic, Primary Care Clinic: Quality Improvement Project

GOAL

The goal of this study was to reduce the percentage of inappropriately prescribed proton pump inhibitors (PPIs) in patients aged 50 and older from 80% (baseline) to 60% within 12 months in an academic, internal medicine clinic.

BACKGROUND

The use of PPIs has increased drastically worldwide. Internal medicine clinic patients had inappropriate use of PPIs for an average of 4 to 5 years.

STUDY

A multidisciplinary quality improvement team used the Plan-Do-Study-Act Model of health care improvement and performed a root cause analysis to identify barriers to inappropriate use of PPIs. The outcome measure was the percentage of patients inappropriately prescribed PPI. Process measures were completion rates of PPI risk assessment and esophagogastroduodenoscopy. Interventions included the creation of customized electronic health record templates and education to providers and patients. Analysis was performed using monthly statistical process control charts.

RESULTS

The average rate of PPI discontinuation was 51.1% (n=92/180), which corresponds to 30.0% inappropriate PPI usage within 12 months. The mean PPI discontinuation rate in the 1-year prestudy, study and 6 months poststudy period was 2.0%, 32.0%, and 49.7%, respectively. The mean esophagogastroduodenoscopy completion rate was 49.8% from the baseline of <30%.

CONCLUSIONS

We achieved a statistically significant and sustainable reduction of inappropriate PPI use to 30% from the baseline rates of 80% and surpassed our goal within 12 months. This quality improvement was unique as no pharmacy personnel was utilized in this process. The multifaceted strategies in a safety-net internal medicine clinic resulted in successful deprescribing of PPI and can be replicated in other setting.

Stress Ulcer Prophylaxis in Neurocritical Care

Stress ulcer prophylaxis (SUP) with acid-suppressive drug therapy is widely utilized in critically ill patients following neurologic injury for the prevention of clinically important stress-related gastrointestinal bleeding (CIB). Data supporting SUP, however, largely originates from studies conducted during an era where practices were vastly different than what is considered routine by today's standard. This is particularly true in neurocritical care patients. In fact, the routine provision of SUP has been challenged due to an increasing prevalence of adverse drug events with acid-suppressive therapy and the perception that CIB rates are sparse. This narrative review will discuss current controversies with SUP as they apply to neurocritical care patients. Specifically, the pathophysiology, prevalence, and risk factors for CIB along with the comparative efficacy, safety, and cost-effectiveness of acid-suppressive therapy will be described.

The risks of long-term use of proton pump inhibitors: a critical review

Proton pump inhibitors (PPIs) are among the most frequently prescribed medications. Their use is likely even higher than estimated due to an increase in the number of PPIs available without a prescription. Appropriate indications for PPI use include Helicobacter pylori infection, erosive esophagitis, gastric ulcers, and stress ulcer prevention in high-risk critically ill patients. Unfortunately, PPIs are often used off-label for extended periods of time. This increase in PPI usage over the past two decades has called into question the long-term effects of these medications. The association between PPI use and infection, particularly Clostridium difficile and pneumonia, has been the subject of several studies. It’s proposed that the alteration in gastrointestinal microflora by PPIs produces an environment conducive to development of these types of infections. At least one study has suggested that long-term PPI use increases the risk of dementia. Drug interactions are an important and often overlooked consideration when prescribing any medication. The potential interaction between PPIs and antiplatelet agents has been the subject of multiple studies. One of the more recent concerns with PPI use is their role in the development or progression of chronic kidney disease. There is also some literature suggesting that PPIs contribute to the development of various micronutrient deficiencies. Most of the literature examining the potential adverse effects of PPI use is composed of retrospective, observation studies. There is a need for higher quality studies exploring this relationship.

Safety assessment of omeprazole use: a review

BACKGROUND

Risks regarding hospital admission due to adverse drug reactions and drug interactions from use of omeprazole have been reported. The question guiding the present review was "Which adverse events occur in patients using omeprazole in a Food and Drug Administration-approved and/or off-label manner?" It was also proposed to evaluate the safety of use of omeprazole.

DESIGN AND SETTING

Qualitative narrative review with critical evaluation, in a public university.

METHODS

The PubMed, SCOPUS, LILACS, SciELO, EMBASE and EBSCO databases were searched on July 31, 2018. Studies evaluating adverse events were screened.

RESULTS

72 articles were included, among which 58 reported on adverse drug events (47, adverse drug reactions; 5, drug interactions; and 6, situations of ineffectiveness). 28 adverse drug reactions not described in compendia and drug leaflets were described in these studies: myocardial infarction (6); stroke (2); spontaneous abortion (1); proliferative changes (1); chills (1); heart failure (1); thrombosis (2); and dementia (1), among others. Severe adverse reactions, for instance cardiac problems, Steven-Johnson syndrome and proliferative changes, were identified. The antiplatelet effects of drugs such as clopidogrel, in patients who underwent heart-related surgery, increased the risk of developing cardiac problems, such as cardiovascular death, myocardial infarction and stroke. In newly transplanted patients, decreased absorption of mycophenolate mofetil occurred, thus leading to rejection of transplanted organs.

CONCLUSION

Use of omeprazole should be monitored primarily in patients with heart disorders using antiplatelet agents concomitantly, and in newly transplanted patients using mycophenolic acid, in order to avoid serious adverse reactions.

Comparison of the Hospital-Acquired Clostridium difficile Infection Risk of Using Proton Pump Inhibitors versus Histamine-2 Receptor Antagonists for Prophylaxis and Treatment of Stress Ulcers: A Systematic Review and Meta-Analysis

Background/Aims

Although proton pump inhibitors (PPIs) have been widely used for the prevention and treatment of stress gastric ulcers in hospital settings, there are concerns that PPIs increase the risk of Clostridium difficile infection (CDI). However, little is known about the risk of CDI following PPI and histamine-2 receptor antagonist (H2RA) use. We evaluated the comparative hospital-acquired CDI occurrence risk associated with the concurrent use of PPIs versus H2RAs.

Methods

A systematic search of PubMed, MEDLINE/Ovid, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Web of Science, and Google Scholar through August 19, 2016, identified 12 studies that reported the hospital-acquired CDI occurrence following H2RA and PPI use for the prevention and treatment of stress gastric ulcers. Random-effects pooled odds ratios and 95% confidence intervals were estimated. Heterogeneity was measured using I², and a meta-regression analysis was conducted. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system was used to assess the overall quality of the evidence.

Results

A total of 74,132 patients from 12 observational studies were analyzed. Compared to H2RAs, PPIs increased the risk of CDI by 38.6% (pooled odds ratio, 1.386; 95% confidence interval, 1.152 to 1.668; p=0.001; I²=42.81%). Subgroup analyses of the purpose of study medication use, study site, and study design confirmed the consistency of a greater CDI risk with PPIs than with H2RAs. The overall quality of evidence was rated as low.

Conclusions

The use of PPIs for both the prevention and treatment of stress ulcers was associated with a 38.6% increased risk of hospital-acquired CDI occurrence compared to H2RA use.

Factors associated with an outbreak of hospital-onset, healthcare facility-associated Clostridium difficile infection (HO-HCFA CDI) in a Mexican tertiary care hospital: A case-control study

Objective

To identify clinical and environmental factors associated with an outbreak of hospital-onset, healthcare facility-associated Clostridium difficile infection (HO-HCFA CDI).

Design

Case-control study.

Setting

Public, acute care, academic tertiary referral center in Mexico.

Patients

Adults hospitalized ≥48 hours between January 2015 and December 2016 were included. Cases were patients with a first episode of HO-HCFA CDI. Controls were patients with any other diagnosis; they were randomly selected from the hospital discharge database and matched in a 1:2 manner according to the date of diagnosis of case ± 10 days. Variables with p<0.1 were considered for multivariable analysis.

Results

One hundred and fifty-five cases and 310 controls were included. Variables independently associated with HO-HCFA CDI were: exposure to both ciprofloxacin and proton pump inhibitor (PPI) within the last 3 months (OR = 8.07, 95% CI = 1.70–38.16), febrile neutropenia (OR = 4.61, 95% CI = 1.37–15.46), intraabdominal infection (OR = 2.06, 95% CI = 0.95–4.46), referral from other hospitals (OR = 1.99, 95% CI = 0.98–4.05) and an increasing number of antibiotics previously used (OR = 1.28, 95% CI = 1.13–1.46).

Conclusions

Multiple factors were found to be associated with the first episode of HO-HCFA CDI in the setting of an outbreak; of the modifiable risk factors, prior exposure to both ciprofloxacin and PPI was the most important. Referral from other hospitals was an environmental risk factor that deserves further study.

Clinical Practice Guidelines for Clostridium difficile Infection in Adults and Children: 2017 Update by the Infectious Diseases Society of America (IDSA) and Society for Healthcare Epidemiology of America (SHEA)

A panel of experts was convened by the Infectious Diseases Society of America (IDSA) and Society for Healthcare Epidemiology of America (SHEA) to update the 2010 clinical practice guideline on Clostridium difficile infection (CDI) in adults. The update, which has incorporated recommendations for children (following the adult recommendations for epidemiology, diagnosis, and treatment), includes significant changes in the management of this infection and reflects the evolving controversy over best methods for diagnosis. Clostridium difficile remains the most important cause of healthcare-associated diarrhea and has become the most commonly identified cause of healthcare-associated infection in adults in the United States. Moreover, C. difficile has established itself as an important community pathogen. Although the prevalence of the epidemic and virulent ribotype 027 strain has declined markedly along with overall CDI rates in parts of Europe, it remains one of the most commonly identified strains in the United States where it causes a sizable minority of CDIs, especially healthcare-associated CDIs. This guideline updates recommendations regarding epidemiology, diagnosis, treatment, infection prevention, and environmental management.

Acid-Suppressive Therapy and Risk of Infections: Pros and Cons

This narrative review summarises the benefits, risks and appropriate use of acid-suppressing drugs (ASDs), proton pump inhibitors and histamine-2 receptor antagonists, advocating a rationale balanced and individualised approach aimed to minimise any serious adverse consequences. It focuses on current controversies on the potential of ASDs to contribute to infections-bacterial, parasitic, fungal, protozoan and viral, particularly in the elderly, comprehensively and critically discusses the growing body of observational literature linking ASD use to a variety of enteric, respiratory, skin and systemic infectious diseases and complications (Clostridium difficile diarrhoea, pneumonia, spontaneous bacterial peritonitis, septicaemia and other). The proposed pathogenic mechanisms of ASD-associated infections (related and unrelated to the inhibition of gastric acid secretion, alterations of the gut microbiome and immunity), and drug-drug interactions are also described. Both probiotics use and correcting vitamin D status may have a significant protective effect decreasing the incidence of ASD-associated infections, especially in the elderly. Despite the limitations of the existing data, the importance of individualised therapy and caution in long-term ASD use considering the balance of benefits and potential harms, factors that may predispose to and actions that may prevent/attenuate adverse effects is evident. A six-step practical algorithm for ASD therapy based on the best available evidence is presented.

Magnitude and direction of the association between Clostridium difficile infection and proton pump inhibitors in adults and pediatric patients: a systematic review and meta-analysis

BACKGROUND

Clostridium difficile infection (CDI) is a cause of increased morbidity and health care costs among hospitalized patients. Proton pump inhibitors (PPIs) are mainly used for the treatment of acid-related upper gastrointestinal diseases. The aim of the study was to assess the risks associated with initial and recurrent CDI in adult and pediatric patients treated with PPIs.

METHODS

A systematic search was performed using PubMed (Medline), Embase, and Web of Science with the following search terms: ("proton pump inhibitor," "PPI," or "acid suppression") AND ("infection," "diarrhea," "diarrhoea," "colitis," or "disease") AND ("Clostridium difficile"). Meta-analysis was performed using Revman5.3 software. Pooled odds ratios (ORs) presented as standard plots with 95% confidence intervals (CIs) were determined.

RESULTS

Sixty-seven eligible studies were selected. PPI use was significantly associated with risk of CDI (OR 2.34, 95% CI 1.94-2.82; P < 0.00001). Pooled data from twelve studies demonstrated a significant association between PPI use and recurrent CDI (OR 1.73, 95% CI 1.39-2.15; P = 0.02). Subgroup analysis revealed significant associations between PPI use and an increased incidence of CDI among adult (OR 2.30, 95% CI 1.89-2.80; P < 0.00001) and pediatric (OR 3.00, 95% CI 1.44-6.23; P < 0.00001) patients.

CONCLUSIONS

PPI use was associated with CDI in adult and pediatric patients, and with recurrent CDI. Although many risk factors are associated with the occurrence and recurrence of CDI, consideration should be given to not administering PPIs at any age if they are unnecessary.

Risk Factors for Community-Associated Clostridium difficile Infection in Adults: A Case-Control Study

BACKGROUND

An increasing proportion of Clostridium difficile infections (CDI) in the United States are community-associated (CA). We conducted a case-control study to identify CA-CDI risk factors.

METHODS

We enrolled participants from 10 US sites during October 2014-March 2015. Case patients were defined as persons age ≥18 years with a positive C. difficile specimen collected as an outpatient or within 3 days of hospitalization who had no admission to a health care facility in the prior 12 weeks and no prior CDI diagnosis. Each case patient was matched to one control (persons without CDI). Participants were interviewed about relevant exposures; multivariate conditional logistic regression was performed.

RESULTS

Of 226 pairs, 70.4% were female and 52.2% were ≥60 years old. More case patients than controls had prior outpatient health care (82.1% vs 57.9%; P < .0001) and antibiotic (62.2% vs 10.3%; P < .0001) exposures. In multivariate analysis, antibiotic exposure-that is, cephalosporin (adjusted matched odds ratio [AmOR], 19.02; 95% CI, 1.13-321.39), clindamycin (AmOR, 35.31; 95% CI, 4.01-311.14), fluoroquinolone (AmOR, 30.71; 95% CI, 2.77-340.05) and beta-lactam and/or beta-lactamase inhibitor combination (AmOR, 9.87; 95% CI, 2.76-340.05),-emergency department visit (AmOR, 17.37; 95% CI, 1.99-151.22), white race (AmOR 7.67; 95% CI, 2.34-25.20), cardiac disease (AmOR, 4.87; 95% CI, 1.20-19.80), chronic kidney disease (AmOR, 12.12; 95% CI, 1.24-118.89), and inflammatory bowel disease (AmOR, 5.13; 95% CI, 1.27-20.79) were associated with CA-CDI.

CONCLUSIONS

Antibiotics remain an important risk factor for CA-CDI, underscoring the importance of appropriate outpatient prescribing. Emergency departments might be an environmental source of CDI; further investigation of their contribution to CDI transmission is needed.

Updated meta-analysis of controlled observational studies: proton-pump inhibitors and risk of Clostridium difficile infection

Attention has recently been directed toward a plausible link between Clostridium difficile infection (CDI) and proton-pump inhibitors (PPIs). However, the results of studies on the association between CDI and PPI remain controversial. We searched the literature databases from their inception to December 2016, without restriction of language, including all controlled observational studies examining the association between acid-suppressive therapy and CDI. Pooled analysis of 50 studies showed a significant association between PPI use and risk of developing CDI (odds ratio: 1.26; 95% confidence interval: 1.12-1.39) as compared with non-users. When stratified by study patients, the relative risk of hospital-acquired CDI and community-associated CDI were 1.29 (1.14-1.44) and 1.17 (0.74-1.59). After restricting the studies according to hospital department, the relative risks of hospital-acquired CDI in ICUs and general wards were 1.43 (0.74-2.11) and 1.29 (1.13-1.45). By implementing cumulative meta-analysis, it was clear that earlier trials of CDI conducted in the early 2000s demonstrated a high degree of heterogeneity and a high percentage of negative results. Since 2011, the overall association between PPI use and risk of developing CDI has remained relatively stable within an effect size between OR 1.20 and 1.26. Our findings indicate a significant associated risk of incident CDI among PPI users, especially in general ward patients. The totality of evidence, when using cumulative meta-analysis, showed that further trials are unlikely to overturn this positive result. Therefore establishing a guideline for the use of PPIs may help in future with the control of CDI.

Patient-centered Outcomes with Concomitant Use of Proton Pump Inhibitors and Other Drugs

PURPOSE

We performed a systematic review of patient-centered outcomes after the concomitant use of proton pump inhibitors (PPIs) and other drugs.

METHODS

We searched 4 databases in July 2016 to find studies that reported mortality and morbidity after the concomitant use of PPIs and other drugs. We conducted direct meta-analyses using a random-effects model and graded the quality of evidence according to the Grading of Recommendations Assessment, Development and Evaluation working group approach.

FINDINGS

We included data from 17 systematic reviews and meta-analyses, 16 randomized controlled trials, and 16 observational studies that examined the concomitant use of PPIs with medications from 10 drug classes. Low-quality evidence suggests that the use of PPIs is associated with greater morbidity when administered with antiplatelet drugs, bisphosphonates, antibiotics, anticoagulants, metformin, mycophenolate mofetil, or nelfinavir. Concomitant PPIs reduce drug-induced gastrointestinal bleeding and are associated with greater docetaxel and cisplatin response rates in patients with metastatic breast cancer. For demonstrated statistically significant relative risks and benefits from concomitant PPIs, the magnitudes of the effects are small, with <100 attributable events per 1000 patients treated, and the effects are inconsistent among specific drugs. Among individual PPIs, the concomitant use of pantoprazole or esomeprazole, but not omeprazole or lansoprazole, is associated with an increased risk for all-cause mortality, nonfatal myocardial infarction, or stroke. Clopidogrel is associated with a greater risk for myocardial infarction compared with prasugrel. Conflicting results between randomized controlled trials and observational studies and high risk for bias in the body of evidence lessened our confidence in the results.

IMPLICATIONS

Available evidence suggests a greater risk for adverse patient outcomes after the concomitant use of PPIs and medications from 9 drug classes and warns against inappropriate drug combinations.

Assessing the Risk of Hospital-Acquired Clostridium Difficile Infection With Proton Pump Inhibitor Use: A Meta-Analysis

BACKGROUND Clostridium difficile is the principal infectious cause of antibiotic-associated diarrhea and accounts for 12% of hospital-acquired infections. Recent literature has shown an increased risk of C. difficile infection (CDI) with proton pump inhibitor (PPI) use. OBJECTIVE To conduct a systematic assessment of the risk of hospital-acquired CDI following exposure to PPI. METHODS We searched multiple databases for studies examining the relationship between PPI and hospital-acquired CDI. Pooled odds ratios were generated and assessment for heterogeneity performed. RESULTS We found 23 observational studies involving 186,033 cases that met eligibility criteria. Across studies, 10,307 cases of hospital-acquired CDI were reported. Significant heterogeneity was present; therefore, a random effects model was used. The pooled odds ratio was 1.81 (95% CI, 1.52-2.14), favoring higher risk of CDI with PPI use. Significant heterogeneity was present, likely due to differences in assessment of exposure, study population, and definition of CDI. DISCUSSION This meta-analysis suggests PPIs significantly increase the risk of hospital-acquired CDI. Given the significant health and economic burden of CDI and the risks of PPI, optimization of PPI use should be included in a multifaceted approach to CDI prevention. Infect Control Hosp Epidemiol 2016;1408-1417.

Causes, Burden, and Prevention of Clostridium difficile Infection

Clostridium difficile infection (CDI) is a potentially deadly cause of diarrhea that is virtually always connected to healthcare system exposures, both inpatient and outpatient. Once a disease mainly of hospitals, 75% of CDI cases are now diagnosed outside of hospitals. However, the diagnosis location may not reflect where C. difficile spores were acquired or antibiotic exposure occurred. Changing epidemiology and increasing awareness about the role of every segment of the healthcare system in mediating this disease makes it clear that reducing its burden will also require active participation from all US healthcare professionals.

Incidence and nature of adverse reactions to antibiotics used as endocarditis prophylaxis

OBJECTIVES

Antibiotic prophylaxis (AP) administration prior to invasive dental procedures has been a leading focus of infective endocarditis prevention. However, there have been long-standing concerns about the risk of adverse drug reactions as a result of this practice. The objective of this study was to identify the incidence and nature of adverse reactions to amoxicillin and clindamycin prophylaxis to prevent infective endocarditis.

METHODS

We obtained AP prescribing data for England from January 2004 to March 2014 from the NHS Business Services Authority, and adverse drug reaction data from the Medicines and Healthcare Products Regulatory Agency's Yellow Card reporting scheme for prescriptions of the standard AP protocol of a single 3 g oral dose of amoxicillin or a single 600 mg oral dose of clindamycin for those allergic to penicillin.

RESULTS

The reported adverse drug reaction rate for amoxicillin AP was 0 fatal reactions/million prescriptions (in fact 0 fatal reactions for nearly 3 million prescriptions) and 22.62 non-fatal reactions/million prescriptions. For clindamycin, it was 13 fatal and 149 non-fatal reactions/million prescriptions. Most clindamycin adverse drug reactions were Clostridium difficile infections.

CONCLUSIONS

AP adverse drug reaction reporting rates in England were low, particularly for amoxicillin, and lower than previous estimates. This suggests that amoxicillin AP is comparatively safe for patients without a history of amoxicillin allergy. The use of clindamycin AP was, however, associated with significant rates of fatal and non-fatal adverse drug reactions associated with C. difficile infections. These were higher than expected and similar to those for other doses, durations and routes of clindamycin administration.

Regional differences in Clostridium difficile infections in relation to fluoroquinolone and proton pump inhibitor use, Finland, 2008-2011

BACKGROUND

Several antimicrobial agents and proton pump inhibitors (PPIs) have been identified as risk factors for Clostridium difficile infections (CDIs). Nationwide laboratory-based surveillance of CDIs in Finland since 2008 has shown variation in regional CDI rates. We evaluated whether regional differences in CDI rates were associated with antibacterial and PPI use.

METHODS

Data on mean annual incidence rates of CDIs during 2008-2011 in 21 healthcare districts (HDs) were obtained from the National Infectious Disease Register, consumption (median annual use) of antimicrobials and PPIs from the Finnish Medical Agency, availability of molecular diagnostics by a laboratory survey and data on ribotypes from the national reference laboratory. The association over the 4 years was measured by incidence rate ratio (IRR) and we performed both bivariate and multivariate analyses.

RESULTS

During 2008-2011, PPI use increased 27% but fluoroquinolone use was stable. The level of fluoroquinolone use was strongly associated with the mean annual CDI incidence rate in different HDs over the 4-year period, but PPI use had less effect. The molecular diagnostics methodology and PCR ribotype 027 were not independently associated with CDI rate. The final multivariable model only included fluoroquinolone and PPI use; IRR for fluoroquinolones was 2.20 (95% confidence interval (CI), 1.32-3.67; p = 0.003).

CONCLUSIONS

Fluoroquinolone use may play a role in regional differences in CDI rates. Although the use has not recently increased, regionally targeted antimicrobial stewardship campaigns promoting appropriate use of fluoroquinolones should still be encouraged since they may decrease the incidence of CDIs.

Effects of proton pump inhibitors and histamine-2 receptor antagonists on response to fidaxomicin or vancomycin in patients with Clostridium difficile-associated diarrhoea

OBJECTIVE

It has been established that use of proton pump inhibitors (PPIs) is associated with an increased risk of acquiring Clostridium difficile-associated diarrhoea (CDAD). However, it is not known whether the use of PPIs or histamine-2 receptor antagonists (H2RAs) concurrently with CDAD-targeted antibiotic treatment affects clinical response or recurrence rates.

DESIGN

In two phase 3 trials, patients with toxin-positive CDAD were randomised to receive fidaxomicin 200 mg twice daily or vancomycin 125 mg four times daily for 10 days. Only inpatients with CDAD (due to complete medication record availability) were included in this post hoc analysis: 701 patients, of whom 446 (64%) used PPIs or H2RAs during study drug treatment or follow-up. Baseline factors that were statistically significant in univariate analyses were analysed in multivariate analyses of effects on clinical response and recurrence.

RESULTS

Multivariate analysis showed that leukocytosis, elevated creatinine and hypoalbuminemia, but not PPI or H2RA use, were significant factors associated with poor clinical responses. Treatment group was the single significant predictor of recurrence; the probability of recurrence after fidaxomicin therapy was half that following vancomycin therapy.

CONCLUSIONS

Acid-suppressing drugs, used by nearly two-thirds of inpatients with CDAD, did not worsen clinical response or recurrence when used concurrently with fidaxomicin or vancomycin. Therefore, development of CDAD does not require discontinuation of anti-acid treatment in patients who have an indication for continuing PPI or H2RA therapy, such as gastro-oesophageal reflux disease and risk of gastrointestinal bleed.

Adherence to and Outcomes Associated with a Clostridium difficile Guideline at a Large Teaching Institution

PURPOSE

The incidence and virulence of Clostridium difficile infection (CDI) has recently increased. National CDI treatment guidelines stratify patients based on clinical symptoms and recommend treatment based on severity of illness. In 2009, Advocate Lutheran General Hospital (Park Ridge, Illinois) adopted guidelines with treatment algorithms identical to the national guidelines. The purpose of this study was to determine whether patients were being treated in accordance with the CDI guidelines and whether adherence impacted patient outcomes.

METHODS

This was a retrospective, descriptive study. Subjects were identified by CDI-associated ICD-9 codes from July 1, 2009 to June 30, 2011 and stratified by disease severity. Guideline adherence was assessed based on initial treatment selection, and subjects were then further categorized as undertreated (UT), overtreated (OT), or appropriately treated (AT). Secondary endpoints included need for therapy escalation, clinical cure, recurrence rates, 90-day all-cause mortality, proton pump inhibitor (PPI), and antimicrobial use.

RESULTS

Two hundred fifty subjects totaling 324 encounters were analyzed. Overall guideline adherence was 42.9%. Adherence rates by CDI severity were mild-moderate, 53.9%; severe, 39.0%; and severe-complicated, 17.9% (P < .001). Of all the subjects, 42.9% were AT, 30.9% were OT, and 26.2% were UT. Clinical outcomes between UT versus AT subjects were as follows: therapy escalation required, 34.1% versus 27.5% (P = .289); clinical cure, 41.2% versus 55.7% (P = .033); mortality, 24.7% versus 10.1% (P = .003); and recurrence, 44.7% versus 24.8% (P < .02). Clinical outcomes between AT versus OT subjects were as follows: therapy escalation required 27.5% versus 14.4% (P < .02); clinical cure, 55.7% versus 66.7% (P = .089); mortality, 10.1% versus 7.8% (P = .553); recurrence, 24.8% versus 27.8% (P = .871).

CONCLUSIONS

The majority of subjects were not treated according to CDI guidelines, particularly those with severe and severe-complicated disease. UT subjects had worse clinical outcomes and OT subjects failed to show significant improvements in clinical outcomes compared to AT subjects. Emphasis should be placed on CDI guideline adherence as this may be associated with improved outcomes.

Risk factors for recurrence, complications and mortality in Clostridium difficile infection: a systematic review

BACKGROUND

Clostridium difficile infection (CDI) can lead to complications, recurrence, and death. Numerous studies have assessed risk factors for these unfavourable outcomes, but systematic reviews or meta-analyses published so far were limited in scope or in quality.

METHODS

A systematic review was completed according to PRISMA guidelines. An electronic search in five databases was performed. Studies published until October 2013 were included if risk factors for at least one CDI outcome were assessed with multivariate analyses.

RESULTS

68 studies were included: 24 assessed risk factors for recurrence, 18 for complicated CDI, 8 for treatment failure, and 30 for mortality. Most studies accounted for mortality in the definition of complicated CDI. Important variables were inconsistently reported, such as previous episodes and use of antibiotics. Substantial heterogeneity and methodological limitations were noted, mainly in the sample size, the definition of the outcomes and periods of follow-up, precluding a meta-analysis. Older age, use of antibiotics after diagnosis, use of proton pump inhibitors, and strain type were the most frequent risk factors for recurrence. Older age, leucocytosis, renal failure and co-morbidities were frequent risk factors for complicated CDI. When considered alone, mortality was associated with age, co-morbidities, hypo-albuminemia, leucocytosis, acute renal failure, and infection with ribotype 027.

CONCLUSION

Laboratory parameters currently used in European and American guidelines to define patients at risk of a complicated CDI are adequate. Strategies for the management of CDI should be tailored according to the age of the patient, biological markers of severity, and underlying co-morbidities.

Risk factors for recurrence, complications and mortality in Clostridium difficile infection: a systematic review

BACKGROUND

Clostridium difficile infection (CDI) can lead to complications, recurrence, and death. Numerous studies have assessed risk factors for these unfavourable outcomes, but systematic reviews or meta-analyses published so far were limited in scope or in quality.

METHODS

A systematic review was completed according to PRISMA guidelines. An electronic search in five databases was performed. Studies published until October 2013 were included if risk factors for at least one CDI outcome were assessed with multivariate analyses.

RESULTS

68 studies were included: 24 assessed risk factors for recurrence, 18 for complicated CDI, 8 for treatment failure, and 30 for mortality. Most studies accounted for mortality in the definition of complicated CDI. Important variables were inconsistently reported, such as previous episodes and use of antibiotics. Substantial heterogeneity and methodological limitations were noted, mainly in the sample size, the definition of the outcomes and periods of follow-up, precluding a meta-analysis. Older age, use of antibiotics after diagnosis, use of proton pump inhibitors, and strain type were the most frequent risk factors for recurrence. Older age, leucocytosis, renal failure and co-morbidities were frequent risk factors for complicated CDI. When considered alone, mortality was associated with age, co-morbidities, hypo-albuminemia, leucocytosis, acute renal failure, and infection with ribotype 027.

CONCLUSION

Laboratory parameters currently used in European and American guidelines to define patients at risk of a complicated CDI are adequate. Strategies for the management of CDI should be tailored according to the age of the patient, biological markers of severity, and underlying co-morbidities.

Cost-effectiveness of histamine receptor-2 antagonist versus proton pump inhibitor for stress ulcer prophylaxis in critically ill patients*

OBJECTIVE

To examine the cost-effectiveness of using histamine receptor-2 antagonist or proton pump inhibitor for stress ulcer prophylaxis.

DESIGN

Decision analysis model examining costs and effectiveness of using histamine receptor-2 antagonist or proton pump inhibitor for stress ulcer prophylaxis. Costs were expressed in 2012 U.S. dollars from the perspective of the institution and included drug regimens and the following outcomes: clinically significant stress-related mucosal bleed, ventilator-associated pneumonia, and Clostridium difficile infection. Effectiveness was the mortality risk associated with these outcomes and represented by survival. Costs, occurrence rates, and mortality probabilities were extracted from published data.

SETTING

A simulation model.

PATIENTS

A mixed adult ICU population.

INTERVENTIONS

Histamine receptor-2 antagonist or proton pump inhibitor for 9 days of stress ulcer prophylaxis therapy.

MAIN MEASUREMENTS AND RESULTS

Output variables were expected costs, expected survival rates, incremental cost, and incremental survival rate. Univariate sensitivity analyses were conducted to determine the drivers of incremental cost and incremental survival. Probabilistic sensitivity analysis was conducted using second-order Monte Carlo simulation. For the base case analysis, the expected cost of providing stress ulcer prophylaxis was $6,707 with histamine receptor-2 antagonist and $7,802 with proton pump inhibitor, resulting in a cost saving of $1,095 with histamine receptor-2 antagonist. The associated mortality probabilities were 3.819% and 3.825%, respectively, resulting in an absolute survival benefit of 0.006% with histamine receptor-2 antagonist. The primary drivers of incremental cost and survival were the assumptions surrounding ventilator-associated pneumonia and bleed. The probabilities that histamine receptor-2 antagonist was less costly and provided favorable survival were 89.4% and 55.7%, respectively. A secondary analysis assuming equal rates of C. difficile infection showed a cost saving of $908 with histamine receptor-2 antagonists, but the survival benefit of 0.0167% favored proton pump inhibitors.

CONCLUSIONS

Histamine receptor-2 antagonist therapy appears to reduce costs with survival benefit comparable to proton pump inhibitor therapy for stress ulcer prophylaxis. Ventilator-associated pneumonia and bleed are the variables most affecting these outcomes. The uncertainty in the findings justifies a prospective trial.

Community-acquired Clostridium difficile infection: an increasing public health threat

There has been a startling shift in the epidemiology of Clostridium difficile infection over the last decade worldwide, and it is now increasingly recognized as a cause of diarrhea in the community. Classically considered a hospital-acquired infection, it has now emerged in populations previously considered to be low-risk and lacking the traditional risk factors for C. difficile infection, such as increased age, hospitalization, and antibiotic exposure. Recent studies have demonstrated great genetic diversity for C. difficile, pointing toward diverse sources and a fluid genome. Environmental sources like food, water, and animals may play an important role in these infections, apart from the role symptomatic patients and asymptomatic carriers play in spore dispersal. Prospective strain typing using highly discriminatory techniques is a possible way to explore the suspected diverse sources of C. difficile infection in the community. Patients with community-acquired C. difficile infection do not necessarily have a good outcome and clinicians should be aware of factors that predict worse outcomes in order to prevent them. This article summarizes the emerging epidemiology, risk factors, and outcomes for community-acquired C. difficile infection.

Surgical Management of Clostridium difficile Colitis

Clostridium difficile infection (CDI) will progress to fulminant disease in 3 to 5% of cases. With the emergence of hypervirulent, multidrug-resistant strains, the incidence and severity of disease are continuing to rise. Prompt identification, early resuscitation, and treatment are critical in preventing morbidity and mortality in this increasingly common condition. Discontinuation of antibiotics and treatment with oral vancomycin and intravenous or oral metronidazole are first-line treatments, but complicated cases may require surgery. Subtotal colectomy with ileostomy remains the standard of care when toxic megacolon, perforation, or an acute surgical abdomen is present, but mortality rates are high. Recognition of risk factors for fulminant CDI and earlier surgical intervention may decrease mortality from this highly lethal disease.

Proton Pump Inhibitors and Clostridium Difficile Infection: Are We Propagating an Already Rapidly Growing Healthcare Problem?

Proton pump inhibitors (PPIs) have been associated with Clostridium difficile infection (CDI) in several recent studies. The exact mechanism through which PPIs may cause Clostridium difficile infection is not well understood. One potential mechanism to explain this association may be that elevated gastric pH levels facilitate the growth of potentially pathogenic upper and lower gastrointestinal tract flora. Although Clostridium difficile spores are acid resistant, vegetative forms are susceptible to acidity. Higher gastric PH therefore increases vegetative bacteria counts in the small and large intestine. Other potential mechanisms include impairment of leukocytes and other immune responses and antimicrobial properties of PPIs. In recent years, much research has been contributed to prove the relationship between PPIs and CDI as causal. Most studies however, fail to prove causality due to the use of antibiotics and other medications during time of initial diagnosis of CDI. PPIs continue to also be one of the most heavily prescribed drugs in our country. As primary and recurrent infection caused by Clostridium difficile continues to rise, more data must be collected to determine better treatment, overall management, and the role that PPIs may play in its propagation.

Clostridium difficile infection in the community: Are proton pump inhibitors to blame?

Once a nosocomial disease, Clostridium difficile infection (CDI) now appears frequently in the community in the absence of exposure to antibiotics. Prior studies have shown that patients with community-acquired CDI are younger, more likely to be female, and have fewer comorbidities compared to patients with hospital-associated CDI. Because most studies of CDI are hospital-based, comparatively little is known about community-acquired CDI. The recent study by Chitnis has received widespread attention because it used active surveillance to capture all cases of community-acquired CDI within a large population and assessed key risk factors. The authors found that low-level healthcare exposure and proton pump inhibitor use were common among those with non-antibiotics associated, community-acquired CDI. In this commentary, we discuss the changing epidemiology of community-acquired CDI and the evidence basis for the controversial association between proton pump inhibitors and community-acquired CDI.

Incidence of Campylobacter and Salmonella infections following first prescription for PPI: a cohort study using routine data

OBJECTIVES

To examine the incidence of Campylobacter and Salmonella infection in patients prescribed proton pump inhibitors (PPIs) compared with controls.

METHODS

Retrospective cohort study using anonymous general practitioner (GP) data. Anonymised individual-level records from the Secure Anonymised Information Linkage (SAIL) system between 1990 and 2010 in Wales were selected. Data were available from 1,913,925 individuals including 358,938 prescribed a PPI. The main outcome measures examined included incidence of Campylobacter or Salmonella infection following a prescription for PPI.

RESULTS

The rate of Campylobacter and Salmonella infections was already at 3.1-6.9 times that of non-PPI patients even before PPI prescription. The PPI group had an increased hazard rate of infection (after prescription for PPI) of 1.46 for Campylobacter and 1.2 for Salmonella, compared with baseline. However, the non-PPI patients also had an increased hazard ratio with time. In fact, the ratio of events in the PPI group compared with the non-PPI group using the prior event rate ratio was 1.17 (95% CI 0.74-1.61) for Campylobacter and 1.00 (0.5-1.5) for Salmonella.

CONCLUSIONS

People who go on to be prescribed PPIs have a greater underlying risk of gastrointestinal (GI) infection beforehand and they have a higher prevalence of risk factors before PPI prescription. The rate of diagnosis of infection is increasing with time regardless of PPI use, and there is no evidence that PPI is associated with an increase in diagnosed GI infection. It is likely that factors associated with the demographic profile of the patient are the main contributors to increased rate of GI infection for patients prescribed PPIs.

Differences in utilisation of gastroprotective drugs between 2001 and 2005 in Australia and Nova Scotia, Canada

PURPOSE

This study aimed to compare use of histamine H2 receptor antagonists (H2RAs) and proton pump inhibitors (PPIs), 2001-2005, in the elderly and social security beneficiaries in Australia (AUS) and Nova Scotia, Canada (NS).

METHODS

Prescription dispensing data were collected for all subsidised H2RAs and PPIs. In AUS, dispensing data for concession beneficiaries were obtained from the Pharmaceutical Benefits Scheme database. In NS, data were sourced from the Pharmacare database. Relevant population data were used to convert to World Health Organisation Anatomic Therapeutic Chemical defined daily doses (2005) per 1000 beneficiaries per day (DDD/1000/day).

RESULTS

Overall use of gastroprotective agents was similar and rising in NS and AUS (100-160 DDD/1000/day) over this 5-year time window. However, the proportion of this use accounted for by PPIs was far higher in AUS (over 85% by 2005) than in NS (23% rising to 35% over the 5 years). In AUS, PPI use rose from 50 to about 140 DDD/1000/day over the 5 years, whereas PPI use in NS rose slowly to less than 60 DDD/1000/day by 2005. H2RA use in NS was always high (over 100 DDD/1000/day), whereas in AUS, H2RA use fell from 54 to around 24 DDD/1000/day over this period.

CONCLUSIONS

AUS had much higher use of PPIs than NS over 2001-2005. The proportion of PPIs in all gastroprotective agents rose in AUS to be nearly 90%. The differences in utilisation during this time window could lead to differences in health outcomes from either lower gastro-intestinal bleeding risk or higher long-term adverse effects of PPIs.

Validation of the chronic disease score-infectious disease (CDS-ID) for the prediction of hospital-associated clostridium difficile infection (CDI) within a retrospective cohort

Background

Aggregate comorbidity scores are useful for summarizing risk and confounder control in studies of hospital-associated infections. The Chronic Disease Score – Infectious Diseases (CDS-ID) was developed for this purpose, but it has not been validated for use in studies of Clostridium difficile Infection (CDI). The aim of this study was to assess the discrimination, calibration and potential for confounder control of CDS-ID compared to age alone or individual comorbid conditions.

Methods

Secondary analysis of a retrospective cohort study of adult inpatients with 2 or more days of antibiotic exposure at a tertiary care facility during 2005. Logistic regression models were used to predict the development of CDI up to 60 days post-discharge. Model discrimination and calibration were assessed using the c-statistic and Hosmer-Lemeshow (HL) tests, respectively. C-statistics were compared using chi-square tests.

Results

CDI developed in 185 out of 7,792 patients. The CDS-ID was a better standalone predictor of CDI than age (c-statistic 0.653 vs 0.609, P=0.04). The best discrimination was observed when CDS-ID and age were both used to predict CDI (c-statistic 0.680). All models had acceptable calibration (P>0.05).

Conclusion

The CDS-ID is a valid tool for summarizing risk of CDI associated with comorbid conditions.

The association between histamine 2 receptor antagonist use and Clostridium difficile infection: a systematic review and meta-analysis

BACKGROUND

Clostridium difficile infection (CDI) is a major health problem. Epidemiological evidence suggests that there is an association between acid suppression therapy and development of CDI.

PURPOSE

We sought to systematically review the literature that examined the association between histamine 2 receptor antagonists (H2RAs) and CDI.

DATA SOURCE

We searched Medline, Current Contents, Embase, ISI Web of Science and Elsevier Scopus from 1990 to 2012 for all analytical studies that examined the association between H2RAs and CDI.

STUDY SELECTION

Two authors independently reviewed the studies for eligibility.

DATA EXTRACTION

Data about studies characteristics, adjusted effect estimates and quality were extracted.

DATA SYNTHESIS

Thirty-five observations from 33 eligible studies that included 201834 participants were analyzed. Studies were performed in 6 countries and nine of them were multicenter. Most studies did not specify the type or duration of H2RAs therapy. The pooled effect estimate was 1.44, 95% CI (1.22-1.7), I(2) = 70.5%. This association was consistent across different subgroups (by study design and country) and there was no evidence of publication bias. The pooled effect estimate for high quality studies was 1.39 (1.15-1.68), I2 = 72.3%. Meta-regression analysis of 10 study-level variables did not identify sources of heterogeneity. In a speculative analysis, the number needed to harm (NNH) with H2RAs at 14 days after hospital admission in patients receiving antibiotics or not was 58, 95% CI (37, 115) and 425, 95% CI (267, 848), respectively. For the general population, the NNH at 1 year was 4549, 95% CI (2860, 9097).

CONCLUSION

In this rigorous systematic review and meta-analysis, we observed an association between H2RAs and CDI. The absolute risk of CDI associated with H2RAs is highest in hospitalized patients receiving antibiotics.

An automated tool for detecting medication overuse based on the electronic health records

PURPOSE

Medication overuse is a serious concern in healthcare as it leads to increased expenditures, side effects, and morbidities. Identifying overuse is only possible through excluding appropriate indications that are primarily mentioned in unstructured notes. We developed a framework for automatic identification of medication overuse and applied it to proton pump inhibitors (PPIs).

METHODS

We first created an indications knowledge base using data from drug labels, clinical guidelines, expert opinion, and other sources. We also obtained the list of current problems for 200 randomly selected inpatients who received PPIs using a natural language processing system and the discharge summaries of those patients. These problems were checked against the indications knowledge base to identify overuse candidates. Two gastroenterologists manually reviewed the notes and identified cases of overuse. Results from the automated framework were compared with the manual review.

RESULTS

Reviewers had high interrater reliability in finding indications (agreement = 92.1%, Cohen's κ = 0.773). In 137 notes included in the final analysis, our system identified indications with a sensitivity of 74% (95%CI = 59-86) and specificity of 95% (95%CI = 87-98). In cases of appropriate use where the automated system also found one or more indications, it always included the correct indication.

CONCLUSIONS

We created an automated system that can identify established indications of medication use in electronic health records with high accuracy. It can provide clinical decision support for identifying potential overuse of PPIs and could be useful for reducing overuse and encouraging better documentation of indications.

Clostridium difficile infection in the inflammatory bowel disease patient

Clostridium difficile infection (CDI) has been increasing in frequency and severity in patients with inflammatory bowel disease (IBD). Population based and single center studies have shown worse clinical outcomes in concomitant CDI and IBD, with several reporting longer length of hospital stay, higher colectomy rates and increased mortality. Clinically, CDI may be difficult to distinguish from an IBD flare and may range from an asymptomatic carrier state to severe life threatening colitis. The traditional risk factors for CDI have included hospitalization, antibiotic use, older age and severe co-morbid disease but IBD patients have several distinct characteristics including younger age, community acquisition, lack of antibiotic exposure, colonic IBD and steroid use. CDI can occur in the small bowel and specifically in ulcerative colitis patients who have had a colectomy and an ileal pouch anal anastomosis. PCR based assays and combination Elisa algorithms have improved the sensitivity and specificity of testing, though in IBD patients have raised clinical questions about how to best manage diarrhea in the setting of possible C. difficile colonization. Treatment modalities for CDI have not been examined in randomized clinical trials in the IBD population. Newer antibiotics, immunotherapy and fecal microbiota transplantation may alter current treatment strategies. This review will focus on the unique epidemiology of CDI in IBD patients, detail clinical disease states, and provide updated diagnostic strategies, prevention and treatment options.

Important clinical advances in the understanding of Clostridium difficile infection

PURPOSE OF REVIEW

Clostridium difficile remains an important cause of infectious colitis, particularly in healthcare facilities. This review summarizes recent advances in the epidemiology, diagnosis, and treatment of this endemic pathogen.

RECENT FINDINGS

C. difficile infection (CDI) hospitalizations and mortality rates have increased over the last decade. The BI/NAP1/027 strain has been responsible for epidemics with increased severity and mortality and is now endemic in many settings, particularly North America. Concurrent antibiotics have now been shown to decrease the cure rates for anti-C. difficile therapy and increase the risk of recurrence. Although studies implicate proton pump inhibitors as a risk for CDI, the magnitude of and the biological basis for that risk remain unclear. Molecular diagnostic techniques are rapid and sensitive but highlight the importance of using appropriate clinical testing criteria. Fidaxomicin is a promising new therapy associated with decreased recurrence; infections due to BI strains, however, are associated with inferior outcomes regardless of the treatment agent. Fecal transplantation continues to have impressive success rates for patients with recurrent CDI, and a new colon-sparing surgical procedure presents an intriguing suggested alternative to total colectomy in severe, complicated cases.

SUMMARY

Elucidating CDI risk factors, identifying rapid, accurate diagnostic tools, and validating new treatment approaches remains an urgent priority.

Association of decreased serum protein fractions with Clostridium difficile infection in the acute care setting: a case–control study

Aim: This study examines the association of decreased levels of serum proteins with the occurrence of Clostridium difficile-associated diarrhea (CDAD) in hospitalized patients. Materials & methods: This is a retrospective case–control study using a case cohort (n = 171) that had been described in an earlier study and a cohort of 332 contemporaneous controls. Results: Patients with CDAD had significantly lower serum levels of albumin, total protein and globulins, and decreased albumin/globulin ratio (p < 0.0001 for all parameters). After adjustment for confounders, hypoproteinemia was more closely associated with CDAD than either hypoalbuminemia or albumin/globulin ratio. Hypoproteinemia exhibited an odds ratios of 10.6 (95% CI: 6.62–17.0) after adjustment for race, and 11.0 (95% CI: 6.88–17.1) after adjustment for age. Conclusion: Decreased total serum protein is more closely associated with CDAD than hypoalbuminemia.

Appropriateness of proton pump inhibitor recommendations at hospital discharge and continuation in primary care

Background:  Inappropriate prescriptions of proton pump inhibitors (PPI) in hospital and primary care have been widely reported. Recommendations from hospital have been implicated as one reason for inappropriate prescriptions of PPI in primary care. Objective:  To quantify the amount of appropriate PPI recommendations in hospital discharge letters and the influence of these recommendations on general practitioners' (GPs') PPI-prescriptions. Materials and Methods:  This is an observational study in 31 primary care practices. We identified patients discharged from hospital with PPI recommendation between 2006 and 2007 and assessed practice records and PPI prescription six months prior and after hospital admission. Hospital recommendation for continuous PPI-treatment and continuation by GPs was classified as appropriate, inappropriate or uncertain. Logistic regression analysis was used to calculate factors associated with indicated and non-indicated PPI continuation. Results:  In 263 (58%) out of 506 patients discharged from 35 hospitals with a PPI recommendation no indication could be found. Non-indicated PPIs were continued by GPs in 58% for at least 1 month. Indicated PPIs were discontinued in 33%. Two thirds of non-indicated PPIs were initiated in hospital. The strongest factor associated with non-indicated continuation was a PPI-prescription prior to hospital admission [OR: 3.0; 95% confidence interval (CI): 1.7-5.4]. This was also the strongest factor for continuation of an indicated PPI medication (OR: 3.2; 95% CI: 1.4-7.5). Conclusions:  We found a strong influence of hospital recommendations and previous prescriptions on PPI prescriptions after discharge. Hospitals should critically review their practice of recommending PPI and document indications. GPs should carefully assess hospital recommendations and their medication prior to admission to avoid over- and under-prescribing.

Risk of Clostridium difficile infection with acid suppressing drugs and antibiotics: meta-analysis

OBJECTIVES

Several studies have raised concern regarding the possible association between proton-pump inhibitors (PPIs) and Clostridium difficile infection (CDI). We aimed to perform a systematic review of incident and recurrent CDI in PPI users, and to evaluate the relative impact of concurrent antibiotic use, or switching acid suppression to histamine-2-receptor antagonists (H2RAs).

METHODS

We searched MEDLINE and EMBASE from inception to December 2011 for controlled observational studies that reported on the risk of CDI with and without PPI use. We performed random effects meta-analysis and assessed statistical heterogeneity using the I(2) statistic.

RESULTS

We included 42 observational studies (30 case-control, 12 cohort) totalling 313,000 participants overall. Pooled analysis of 39 studies showed a statistically significant association between PPI use and risk of developing CDI, odds ratio (OR) 1.74 (95% confidence interval (CI) 1.47-2.85, P<0.001, I(2)=85%) compared with non-users. A pooled analysis of three studies showed a significant associated risk of recurrent CDI associated with PPIs, OR 2.51 (95% CI 1.16-5.44, P=0.005, I(2)=78%). Subgroup analysis failed to fully clarify the source of the substantial statistical heterogeneity. Adjusted indirect comparison demonstrated that use of H2RAs as an alternative carried a lower-risk OR 0.71 (95% CI 0.53-0.97) compared with PPIs. Conversely, concomitant use of PPI and antibiotics conferred a greater-risk OR 1.96 (95% CI 1.03-3.70) above that of PPIs alone. For PPI and antibiotics, the Rothman's synergy index was 1.36 and attributable proportion of risk from interaction 0.19, indicating an increased risk from interaction beyond the effects of each drug alone.

CONCLUSIONS

Despite the substantial statistical and clinical heterogeneity, our findings indicate a probable association between PPI use and incident and recurrent CDI. This risk is further increased by concomitant use of antibiotics and PPI, whereas H2RAs may be less harmful.

Proton pump inhibitor use and recurrent Clostridium difficile-associated disease: a case-control analysis matched by propensity score

BACKGROUND AND AIM

Clostridium difficile has been increasingly diagnosed in hospitalized patients. An association between proton pump inhibitors (PPIs) use and Clostridium difficile-associated disease (CDAD) and between recurrent CDAD has been suggested. The aim of this study is to investigate whether PPI use is associated with the development of recurrent CDAD.

METHODS

This was a retrospective case-control study of patients with CDAD at Yeungnam University Medical Center, seen from January 2004 to December 2008. C. difficile infection was diagnosed by the presence of C. difficile toxin in the stool. Those with recurrent disease were matched with nonrecurrent controls using multivariate matched sampling methods that incorporated the propensity score.

RESULTS

Recurrent CDAD developed in 28 (14.1%) of the 198 patients with diarrhea and positive C. difficile stool toxin assays. Multivariate analysis of the total population of recurrent versus nonrecurrent CDAD revealed that additional use of non-C. difficile antimicrobial therapy (concomitant with the treatment or after or both), poor response to therapy with metronidazole or vancomycin, and recent gastrointestinal surgery were risk factors for recurrent CDAD. We were able to match 21 recurrent CDAD subjects with 21 without recurrent CDAD. Among the matched patients only PPI use was associated with recurrent CDAD (ie, 47.6% vs. 4.8%, P=0.004 for recurrent vs. nonrecurrent CDAD, respectively).

CONCLUSIONS

Among the matched patient groups, only PPI therapy was associated with recurrent CDAD. Prospective studies are needed to clarify whether avoidance of PPIs or specific cotherapies will reduce the incidence of recurrent C. difficile-associated diarrhea.