Fluoroquinolone use and Clostridium difficile-associated diarrhea

Improving Antibiotic Stewardship in a Pediatric Long-term Care Facility

OBJECTIVES

Antimicrobial stewardship is little studied in pediatric long-term care facilities. We sought to determine whether empirical ciprofloxacin for febrile respiratory illnesses could be safely reduced in our pediatric long-term care facility.

METHODS

All patients living in the 45-bed facility were included. A 1-year educational intervention for antimicrobial stewardship was implemented. Days of ciprofloxacin therapy, infections, microbiology, hospitalizations, other antibiotic use, methicillin-resistant Staphylococcus aureus and Clostridioides difficile infections, and mortality were recorded at regular intervals retrospectively from 5 years before intervention and prospectively for 8 years after intervention. Data were analyzed using statistical process control charts.

RESULTS

A majority of patients had tracheostomy tubes (96%) and ventilator dependence (58%). Ciprofloxacin use declined by 76% (17 to 4 days/1000 facility patient days). Antibiotic prescriptions for bacterial tracheitis decreased by 89% (38 to 4 courses per 6-month period). No increases in positive blood or urine cultures, hospitalizations, or need for hospital antibiotics were observed.

CONCLUSIONS

An antimicrobial stewardship intervention in a pediatric long-term care facility led to decreases in ciprofloxacin use, bacterial tracheitis diagnoses, and overall antibiotic use without increasing negative outcomes.

Guidelines for Antibiotics Prescription in Critically Ill Patients

How to cite this article: Khilnani GC, Tiwari P, Mittal S, Kulkarni AP, Chaudhry D, Zirpe KG, et al. Guidelines for Antibiotics Prescription in Critically Ill Patients. Indian J Crit Care Med 2024;28(S2):S104-S216.

Increase of healthcare-onset Clostridioides difficile infection in adult population since SARS-CoV-2 pandemic: A retrospective cohort study in a tertiary care hospital from 2019 to 2022

OBJECTIVES

The aim was to assess the impact of the SARS-CoV-2 pandemic on the prevalence, relative incidence (RI), incidence density (ID), ratio of rate incidence (RRI), rate of incidence density (RID), and relative risks (RR) of healthcare-onset Clostridioides difficile infection (HO-CDI) as well as its correlation with the antibiotic consumption.

METHODS

Demographic and analytical data of adult patients exhibiting diarrhoea and testing positive for C. difficile were systematically collected from a tertiary care hospital in Madrid (Spain). The periods analysed included: prepandemic (P0), first pandemic-year (P1), and second pandemic-year (P2). We compared global prevalence, RI of HO-CDI per 1,000-admissions, ID of HO-CDI per 10,000-patients-days, RRI, RID, and RR. Antibiotic consumption was obtained by number of defined daily dose per 100 patient-days.

RESULTS

In P0, the prevalence of HO-CDI was 7.4% (IC95%: 6.2-8.7); in P1, it increased to 8.7% (IC95%: 7.4-10.1) (p = 0.2), and in P2, it continued to increase to 9.2% (IC95%: 8-10.6) (p < 0.05). During P1, the RRI was 1.5 and RID was 1.4. However, during P2 there was an increase in RRI to 1.6 and RID to 1.6. The RR also reflected the increase in HO-CDI: at P1, the probability of developing HO-CDI was 1.5 times (IC95%: 1.2-1.9) higher than P0, while at P2, this probability increased to 1.6 times (IC95%: 1.3-2.1). There was an increase in prevalence, RI, ID, RR, RRI, and RID during the two postpandemic periods respect to the prepandemic period. During P2, this increase was greater than the P1. Meropenem showed a statistically significant difference increased consumption (p < 0.05) during the pandemic period. Oral vancomycin HO-CDI treatment showed an increase during the period of study (p > 0.05).

CONCLUSIONS

Implementation of infection control measures during the SARS-CoV-2 pandemic did not appear to alleviate the burden of HO-CDI. The escalation in HO-CDI cases did not exhibit a correlation with overall antibiotic consumption, except for meropenem.

Understanding gut microbiome-based machine learning platforms: A review on therapeutic approaches using deep learning

Human beings possess trillions of microbial cells in a symbiotic relationship. This relationship benefits both partners for a long time. The gut microbiota helps in many bodily functions from harvesting energy from digested food to strengthening biochemical barriers of the gut and intestine. But the changes in microbiota composition and bacteria that can enter the gastrointestinal tract can cause infection. Several approaches like culture-independent techniques such as high-throughput and meta-omics projects targeting 16S ribosomal RNA (rRNA) sequencing are popular methods to investigate the composition of the human gastrointestinal tract microbiota and taxonomically characterizing microbial communities. The microbiota conformation and diversity should be provided by whole-genome shotgun metagenomic sequencing of site-specific community DNA associating genome mapping, gene inventory, and metabolic remodelling and reformation, to ease the functional study of human microbiota. Preliminary examination of the therapeutic potency for dysbiosis-associated diseases permits investigation of pharmacokinetic-pharmacodynamic changes in microbial communities for escalation of treatment and dosage plan. Gut microbiome study is an integration of metagenomics which has influenced the field in the last two decades. And the incorporation of artificial intelligence and deep learning through "omics-based" methods and microfluidic evaluation enhanced the capability of identification of thousands of microbes.

Clostridioides difficile Infection in Kidney Transplant Recipients

Clostridioides difficile (C. difficile) is a bacterial organism that typically infects the colon, which has had its homeostasis of healthy gut microbiota disrupted by antibiotics or other interventions. Patients with kidney transplantation are a group that are susceptible to C. difficile infection (CDI) and have poorer outcomes with CDI given that they conventionally require long-term immunosuppression to minimize their risk of graft rejection, weakening their responses to infection. Recognizing the risk factors and complex pathophysiological processes that exist between immunosuppression, dysbiosis, and CDI is important when making crucial clinical decisions surrounding the management of this vulnerable patient cohort. Despite the clinical importance of this topic, there are few studies that have evaluated CDI in the context of kidney transplant recipients and other solid organ transplant populations. The current recommendations on CDI management in kidney transplant and solid organ transplant recipients are mostly extrapolated from data relating to CDI management in the general population. We provide a narrative review that discusses the available evidence examining CDI in solid organ transplant recipients, with a particular focus on the kidney transplant recipient, from the epidemiology of CDI, clinical features and implications of CDI, potential risk factors of CDI, and, ultimately, prevention and management strategies for CDI, with the aim of providing areas for future research development in this topic area.

A novel approach to correcting attribution of Clostridioides difficile in a healthcare setting

Objective

To describe a novel attribution metric estimating the causal source location of healthcare-associated Clostridioides difficile and compare it with the current US National Healthcare Safety Network (NHSN) surveillance reporting standard.

Design

Quality improvement study.

Setting

Two acute care facilities.

Methods

A novel attribution metric assigned days of attribution to locations where patients were located for 14 days before and the day of their C. difficile diagnosis. We correlated the NHSN-assigned unit attribution with the novel attribution measure and compared the proportion of attribution assigned to inpatient units.

Results

During a 30-month period, there were 727 NHSN C. difficile healthcare-associated infections (HAIs) and 409 non-HAIs; the novel metric attributed 17,034 days. The correlation coefficients for NHSN and novel attributions among non-ICU units were 0.79 (95% CI, 0.76-0.82) and 0.74 (95% CI, 0.70-0.78) and among ICU units were 0.70 (95% CI, 0.63-0.76) and 0.69 (95% CI, 0.60-0.77) at facilities A and B, respectively. The distribution of difference in percent attribution showed higher inpatient unit attribution using NHSN measure than the novel attribution metric: 38% of ICU units and 15% of non-ICU units in facility A, and 20% of ICU units and 25% of non-ICU units in facility B had a median difference >0; no inpatient units showed a greater attribution using the novel attribution metric.

Conclusion

The novel attribution metric shifts attribution from inpatient units to other settings and correlates modestly with NHSN methodology of attribution. If validated, the attribution metric may more accurately target C. difficile reduction efforts.

Clostridioides difficile colonization and the frequency of subsequent treatment for C. difficile infection in critically ill patients

OBJECTIVE

To determine risk factors for Clostridioides difficile colonization and C. difficile infection (CDI) among patients admitted to the intensive care unit (ICU).

DESIGN

Retrospective observational cohort study.

SETTING

Tertiary-care facility.

PATIENTS

All adult patients admitted to an ICU from July 1, 2015, to November 6, 2019, who were tested for C. difficile colonization. Patients with CDI were excluded.

METHODS

Information was collected on patient demographics, comorbidities, laboratory results, and prescriptions. We defined C. difficile colonization as a positive nucleic acid amplification test for C. difficile up to 48 hours before or 24 hours after intensive care unit (ICU) admission without evidence of active infection. We defined active infection as the receipt of an antibiotic whose only indication is the treatment of CDI. The primary outcome measure was the development of CDI up to 30 days after ICU admission. Logistic regression was used to model associations between clinical variables and the development of CDI.

RESULTS

The overall C. difficile colonization rate was 4% and the overall CDI rate was 2%. Risk factors for the development of CDI included C. difficile colonization (aOR, 13.3; 95% CI, 8.3-21.3; P < .0001), increased ICU length of stay (aOR, 1.04; 95% CI, 1.03-1.05; P < .0001), and a history of inflammatory bowel disease (aOR, 3.8; 95% CI, 1.3-11.1; P = .02). Receipt of any antibiotic during the ICU stay was associated with a borderline increased odds of CDI (aOR, 1.9; 95% CI, 1.0-3.4; P = .05).

CONCLUSION

C. difficile colonization is associated with the development of CDI among ICU patients.

Association of ward-level antibiotic consumption with healthcare-associated Clostridioides difficile infections: an ecological study in five German university hospitals, 2017-2019

OBJECTIVES

To analyse the influence of antibiotic consumption on healthcare-associated healthcare onset (HAHO) Clostridioides difficile infection (CDI) in a German university hospital setting.

METHODS

Monthly ward-level antibiotic consumption measured in DDD/100 patient days (pd) and CDI surveillance data from five university hospitals in the period 2017 through 2019 were analysed. Uni- and multivariable analyses were performed with generalized estimating equation models.

RESULTS

A total of 225 wards with 7347 surveillance months and 4 036 602 pd participated. With 1184 HAHO-CDI cases, there was a median incidence density of 0.17/1000 pd (IQR 0.03-0.43) across all specialties, with substantial differences among specialties. Haematology-oncology wards showed the highest median incidence density (0.67/1000 pd, IQR 0.44-1.01), followed by medical ICUs (0.45/1000 pd, IQR 0.27-0.73) and medical general wards (0.32/1000 pd, IQR 0.18-0.53). Multivariable analysis revealed carbapenem (mostly meropenem) consumption to be the only antibiotic class associated with increased HAHO-CDI incidence density. Each carbapenem DDD/100 pd administered increased the HAHO-CDI incidence density by 1.3% [incidence rate ratio (IRR) 1.013; 95% CI 1.006-1.019]. Specialty-specific analyses showed this influence only to be valid for haematological-oncological wards. Overall, factors like ward specialty (e.g. haematology-oncology ward IRR 2.961, 95% CI 2.203-3.980) or other CDI cases on ward had a stronger influence on HAHO-CDI incidence density (e.g. community-associated CDI or unknown association case in same month IRR 1.476, 95% CI 1.242-1.755) than antibiotic consumption.

CONCLUSIONS

In the German university hospital setting, monthly ward-level carbapenem consumption seems to increase the HAHO-CDI incidence density predominantly on haematological-oncological wards. Furthermore, other patient-specific factors seem to be equally important to control HAHO-CDI.

Overview of Side-Effects of Antibacterial Fluoroquinolones: New Drugs versus Old Drugs, a Step Forward in the Safety Profile?

Antibacterial fluoroquinolones (FQs) are frequently used in treating infections. However, the value of FQs is debatable due to their association with severe adverse effects (AEs). The Food and Drug Administration (FDA) issued safety warnings concerning their side-effects in 2008, followed by the European Medicine Agency (EMA) and regulatory authorities from other countries. Severe AEs associated with some FQs have been reported, leading to their withdrawal from the market. New systemic FQs have been recently approved. The FDA and EMA approved delafloxacin. Additionally, lascufloxacin, levonadifloxacin, nemonoxacin, sitafloxacin, and zabofloxacin were approved in their origin countries. The relevant AEs of FQs and their mechanisms of occurrence have been approached. New systemic FQs present potent antibacterial activity against many resistant bacteria (including resistance to FQs). Generally, in clinical studies, the new FQs were well-tolerated with mild or moderate AEs. All the new FQs approved in the origin countries require more clinical studies to meet FDA or EMA requirements. Post-marketing surveillance will confirm or infirm the known safety profile of these new antibacterial drugs. The main AEs of the FQs class were addressed, highlighting the existing data for the recently approved ones. In addition, the general management of AEs when they occur and the rational use and caution of modern FQs were outlined.

The Impact of Reported β-Lactam Allergy on Clinical Outcomes and Antibiotic Use Among Solid Organ Transplant Recipients

Background

Reported β-lactam allergies (BLAs) are common and frequently inaccurate, but there are limited data on the clinical implications of BLA among solid organ transplant (SOT) recipients. We examined the impact of BLA on clinical outcomes and antibiotic use among SOT recipients.

Methods

This retrospective cohort study included adult patients undergoing single-organ heart, kidney, liver, lung, or pancreas transplant at a United States academic medical center from 1 April 2017 to 31 December 2020. Demographic and clinical data were collected from the electronic health record. Multivariate median regression was performed to evaluate the association between BLA and days alive and out of the hospital in the first 180 days posttransplant (DAOH180). Multivariate logistic regression was performed to evaluate the association between BLA and antibiotic use.

Results

Among 1700 SOT recipients, 285 (16.8%) had a BLA at the time of transplant. BLA was not associated with DAOH180 (adjusted median difference, -0.8 days [95% confidence interval {CI}, -2.7 to 1.2]; P = .43). Patients with BLA were more likely to receive intravenous vancomycin (adjusted odds ratio [aOR], 1.8 [95% CI, 1.3-2.6]; P < .001), clindamycin (aOR, 9.9 [95% CI, 5.1-18.9]; P < .001), aztreonam (aOR, 19.6 [95% CI, 5.9-64.4]; P < .001), fluoroquinolones (aOR, 3.8 [95% CI, 2.8-5.0]; P < .001), or aminoglycosides (aOR, 3.9 [95% CI, 2.5-6.2]; P < .001).

Conclusions

BLA was associated with use of β-lactam alternative antibiotics but not DAOH180 among SOT recipients.

Association of Adverse Events with Antibiotic Treatment for Urinary Tract Infection

BACKGROUND

Little is known about the relative harms of different antibiotic regimens prescribed to treat uncomplicated urinary tract infection (UTI). We sought to compare the risk of adverse events associated with commonly-used oral antibiotic regimens for the outpatient treatment of uncomplicated UTI.

METHODS

We identified 1,169,033 otherwise healthy, non-pregnant women aged 18-44 years with uncomplicated UTI who initiated an oral antibiotic with activity against common uropathogens from July 1, 2006 to September 30, 2015. We used propensity score-weighted Kaplan-Meier methods and Cox proportional hazards regression models to estimate the association between antibiotic agent and adverse events.

RESULTS

Of two first-line agents, TMP/SMX (versus nitrofurantoin) was associated with higher risk of several adverse drug events including hypersensitivity reaction (hazard ratio [HR] 2.62, 95% CI 2.30-2.98), acute renal failure (HR 2.56, 95% CI 1.55-4.25), skin rash (HR 2.42, 95% CI 2.13-2.75), urticaria (HR 1.37, 95% CI 1.19-1.57), abdominal pain (HR 1.14, 95% CI 1.09-1.19), and nausea / vomiting (HR 1.18, 95% CI 1.10-1.28), but similar risk of potential microbiome-related adverse events. Compared to nitrofurantoin, non-first-line agents were associated with higher risk of several adverse drug events and potential microbiome-related adverse events including non-C. difficile diarrhea, C. difficile infection, vaginitis / vulvovaginal candidiasis, and pneumonia. Treatment duration modified the risk of potential microbiome-related adverse events.

CONCLUSIONS

The risks of adverse drug events and potential microbiome-related events differ widely by antibiotic agent and duration. These findings underscore the utility of using real-world data to fill evidentiary gaps related to antibiotic safety.

Are Fluoroquinolones or Macrolides Better for Treating Legionella Pneumonia? A Systematic Review and Meta-analysis

BACKGROUND

The Infectious Diseases Society of America recommends either a fluoroquinolone or a macrolide as a first-line antibiotic treatment for Legionella pneumonia, but it is unclear which antibiotic leads to optimal clinical outcomes. We compared the effectiveness of fluoroquinolone versus macrolide monotherapy in Legionella pneumonia using a systematic review and meta-analysis.

METHODS

We conducted a systematic search of literature in PubMed, Cochrane, Scopus, and Web of Science from inception to 1 June 2019. Randomized controlled trials and observational studies comparing macrolide with fluoroquinolone monotherapy using clinical outcomes in patients with Legionella pneumonia were included. Twenty-one publications out of an initial 2073 unique records met the selection criteria. Following PRISMA guidelines, 2 reviewers participated in data extraction. The primary outcome was mortality. Secondary outcomes included clinical cure, time to apyrexia, length of hospital stay (LOS), and the occurrence of complications. The review and meta-analysis was registered with PROSPERO (CRD42019132901).

RESULTS

Twenty-one publications with 3525 patients met inclusion criteria. The mean age of the population was 60.9 years and 67.2% were men. The mortality rate for patients treated with fluoroquinolones was 6.9% (104/1512) compared with 7.4% (133/1790) among those treated with macrolides. The pooled odds ratio assessing risk of mortality for patients treated with fluoroquinolones versus macrolides was 0.94 (95% confidence interval, .71-1.25, I2 = 0%, P = .661). Clinical cure, time to apyrexia, LOS, and the occurrence of complications did not differ for patients treated with fluoroquinolones versus macrolides.

CONCLUSIONS

We found no difference in the effectiveness of fluoroquinolones versus macrolides in reducing mortality among patients with Legionella pneumonia.

Comparative Effectiveness and Harms of Antibiotics for Outpatient Diverticulitis : Two Nationwide Cohort Studies

BACKGROUND

Outpatient diverticulitis is commonly treated with either a combination of metronidazole and a fluoroquinolone (metronidazole-with-fluoroquinolone) or amoxicillin-clavulanate alone. The U.S. Food and Drug Administration advised that fluoroquinolones be reserved for conditions with no alternative treatment options. The comparative effectiveness of metronidazole-with-fluoroquinolone versus amoxicillin-clavulanate for diverticulitis is uncertain.

OBJECTIVE

To determine the effectiveness and harms of metronidazole-with-fluoroquinolone versus amoxicillin-clavulanate for outpatient diverticulitis.

DESIGN

Active-comparator, new-user, retrospective cohort studies.

SETTING

Nationwide population-based claims data on U.S. residents aged 18 to 64 years with private employer-sponsored insurance (2000 to 2018) or those aged 65 years or older with Medicare (2006 to 2015).

PARTICIPANTS

Immunocompetent adults with diverticulitis in the outpatient setting.

INTERVENTION

Metronidazole-with-fluoroquinolone or amoxicillin-clavulanate.

MEASUREMENTS

1-year risks for inpatient admission, urgent surgery, and Clostridioides difficile infection (CDI) and 3-year risk for elective surgery.

RESULTS

In MarketScan (IBM Watson Health), new users of metronidazole-with-fluoroquinolone (n = 106 361) and amoxicillin-clavulanate (n = 13 160) were identified. There were no differences in 1-year admission risk (risk difference, 0.1 percentage points [95% CI, -0.3 to 0.6]), 1-year urgent surgery risk (risk difference, 0.0 percentage points [CI, -0.1 to 0.1]), 3-year elective surgery risk (risk difference, 0.2 percentage points [CI, -0.3 to 0.7]), or 1-year CDI risk (risk difference, 0.0 percentage points [CI, -0.1 to 0.1]) between groups. In Medicare, new users of metronidazole-with-fluoroquinolone (n = 17 639) and amoxicillin-clavulanate (n = 2709) were identified. There were no differences in 1-year admission risk (risk difference, 0.1 percentage points [CI, -0.7 to 0.9]), 1-year urgent surgery risk (risk difference, -0.2 percentage points [CI, -0.6 to 0.1]), or 3-year elective surgery risk (risk difference, -0.3 percentage points [CI, -1.1 to 0.4]) between groups. The 1-year CDI risk was higher for metronidazole-with-fluoroquinolone than for amoxicillin-clavulanate (risk difference, 0.6 percentage points [CI, 0.2 to 1.0]).

LIMITATION

Residual confounding is possible, and not all harms associated with these antibiotics, most notably drug-induced liver injury, could be assessed.

CONCLUSION

Treating diverticulitis in the outpatient setting with amoxicillin-clavulanate may reduce the risk for fluoroquinolone-related harms without adversely affecting diverticulitis-specific outcomes.

PRIMARY FUNDING SOURCE

National Institutes of Health.

Gram-Negative Taxa and Antimicrobial Susceptibility after Fecal Microbiota Transplantation for Recurrent Clostridioides difficile Infection

Fecal microbiota transplantation (FMT) has promising applications in reducing multidrug-resistant organism (MDRO) colonization and antibiotic resistance (AR) gene abundance. However, data on clinical microbiology results after FMT are limited. We examined the changes in antimicrobial susceptibility profiles in patients with Gram-negative infections in the year before and the year after treatment with FMT for recurrent Clostridioides difficile infection (RCDI). We also examined whether a history of FMT changed health care provider behavior with respect to culture ordering and antibiotic prescription. Medical records for RCDI patients who underwent FMT at Emory University between July 2012 and March 2017 were reviewed retrospectively. FMT-treated patients with Gram-negative culture data in the 1-year period preceding and the 1-year period following FMT were included. Demographic and clinical data were abstracted, including CDI history, frequency of Gram-negative cultures, microbiological results, and antibiotic prescription in response to positive cultures in the period following FMT. Twelve patients were included in this case series. We pooled data from infections at all body sites and found a decrease in the number of total and Gram-negative cultures post-FMT. We compared susceptibility profiles across taxa given the potential for horizontal transmission of AR elements and observed increased susceptibility to nitrofurantoin, trimethoprim-sulfamethoxazole, and the aminoglycosides. FMT did not drastically influence health care provider ordering of bacterial cultures or antibiotic prescribing practices. We observed a reduction in Gram-negative cultures and a trend toward increased antimicrobial susceptibility. This study supports further investigation of FMT as a means of improving antimicrobial susceptibility.IMPORTANCE Fecal microbiota transplantation (FMT), which is highly efficacious in treating recurrent C. difficile infection (RCDI), has a promising application in decolonization of multidrug-resistant organisms, reduction of antibiotic resistance gene abundance, and restoration of healthy intestinal microbiota. However, data representing clinical microbiology results after FMT are limited. We sought to characterize the differences in culture positivity and antimicrobial susceptibility profiles in patients with Gram-negative infections in the year before and the year after FMT for RCDI. Drawing on prior studies that had demonstrated the success of FMT in eradicating extraintestinal infections and the occurrence of patient-level interspecies transfer of resistance elements, we employed an agnostic analytic approach of reviewing the data irrespective of body site or species. In a small RCDI population, we observed an improvement in the antimicrobial susceptibility profile of Gram-negative bacteria following FMT, which supports further study of FMT as a strategy to combat antibiotic resistance.

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.

Incidence of healthcare-associated Clostridioides difficile infections and association with ward-level antibiotic consumption in a German university hospital: an ecological study

OBJECTIVES

Clostridioides difficile infection (CDI) is one of the most important healthcare-associated infections. We aimed to describe the incidence density of healthcare-associated CDI (HA-CDI) in Germany's largest hospital and to identify associations with ward-level antimicrobial consumption.

METHODS

We used surveillance data on CDI and antimicrobial consumption from 2014 to 2017 and analysed a potential association by means of multivariable regression analysis.

RESULTS

We included 77 wards with 404998 admitted patients and 1850862 patient-days. Six hundred and seventy-one HA-CDI cases were identified, resulting in a pooled mean incidence density of 0.36/1000 patient-days (IQR = 0.34-0.39). HA-CDI incidence density on ICU and haematological-oncological wards was about three times higher than on surgical wards [incidence rate ratio (IRR) = 3.00 (95% CI = 1.96-4.60) and IRR = 2.78 (95% CI = 1.88-4.11), respectively]. Ward-level consumption of third-generation cephalosporins was the sole antimicrobial risk factor for HA-CDI. With each DDD/100 patient-days administered, a ward's HA-CDI incidence density increased by 2% [IRR = 1.02 (95% CI = 1.01-1.04)]. Other risk factors were contemporaneous community-associated CDI cases [IRR = 1.32 (95% CI = 1.07-1.63)] and CDI cases in the previous month [IRR = 1.27 (95% CI = 1.07-1.51)]. Furthermore, we found a significant decrease in HA-CDI in 2017 compared with 2014 [IRR = 0.68 (95% CI = 0.54-0.86)].

CONCLUSIONS

We confirmed that ward-level antimicrobial use influences HA-CDI and specifically identified third-generation cephalosporin consumption as a risk factor.

Outpatient fluoroquinolone prescribing patterns before and after US FDA boxed warning

OBJECTIVES

Fluoroquinolones are routinely overprescribed for uncomplicated urinary tract infection (uUTI), acute sinusitis, and acute bronchitis. In 2016, the United States (US) Food and Drug Administration (FDA) updated the boxed warning on fluoroquinolones, recommending against their use as first-line agents for the routine pharmacologic management of uUTI, acute sinusitis, and acute bronchitis in patients who have other treatment options. The primary objective of this study was to determine if the 2016 expanded boxed warning was associated with decreased fluoroquinolone prescription rates for these three diagnoses.

METHODS

We retrospectively reviewed antibiotics prescribed at a single, large, academic outpatient center for these three diagnoses between January 2013 and May 2018. Interrupted time series analysis was used to compare the rate of fluoroquinolone prescriptions before and after the May 2016 FDA boxed warning.

RESULTS

A total of 10 087 antibiotic prescriptions for these three diagnoses were examined. There was no significant change in fluoroquinolone prescription rates after the FDA boxed warning. The majority of inappropriate fluoroquinolone prescriptions were given for the management of uUTI.

CONCLUSION

The 2016 US FDA boxed warning against fluoroquinolone use for uUTI, acute sinusitis, and acute bronchitis was not associated with a statistically significant reduction in the rate of fluoroquinolone prescriptions for these diagnoses. Additional research is needed to define how US FDA boxed warnings may be incorporated into broader antibiotic stewardship programs to decrease overuse of fluoroquinolones and avoid adverse effects of the drug class, including Clostridioides difficile infections and emergence of resistant organisms.

Appropriateness of Antibiotic Prescriptions for Urinary Tract Infections

Introduction

Urinary tract infections (UTI) are a common indication for antibiotic use in the emergency department (ED). With antibiotic resistance on the rise, it is essential that antibiotics be prescribed appropriately for UTIs. Our objective was to evaluate the appropriateness of antibiotic prescriptions by ED providers for uncomplicated cystitis and pyelonephritis.

Methods

We conducted a retrospective study of females ages 2–50 years seen in an academic ED from January 2017 to April 2018 diagnosed with UTI. We assessed the appropriateness of discharge antibiotic prescriptions, as determined by adherence to clinical practice guidelines, best evidence for the particular indication (cystitis vs pyelonephritis for children and adults), and the local antibiogram.

Results

A total of 421 patients were included in this study. Of these, 60 children and 198 adults were diagnosed with cystitis, and 47 children and 116 adults were diagnosed with pyelonephritis. Treatment in the absence of true infection was common, with culture-confirmed UTI occurring in only 17/50 (34%) of children and 60/129 (47%) of adults diagnosed with cystitis, and 23/40 (58%) of children and 58/87 (67%) of adults diagnosed with pyelonephritis, among patients who had urine cultures. The type of antibiotic prescribed was appropriate in 53/60 (88%) of children and 135/198 (68%) of adults with cystitis, and 38/47 (81%) of children and 53/116 (46%) of adults with pyelonephritis. The most common inappropriate antibiotic types were beta-lactams in adults (n = 92), nitrofurantoin for pyelonephritis (n = 16), and amoxicillin (n = 15). Dosing and duration errors were also common, occurring in 122/279 (44%) of prescriptions of an appropriate antibiotic type. The frequency of errors in the type of antibiotic prescribed was similar among provider types (attending physician, resident physician, and advanced practice clinician; p = 0.926).

Conclusion

This study reveals room for improvement in antibiotic prescription practices across provider cohorts in the ED for the management of uncomplicated cystitis and pyelonephritis in females.

Practitioner Education and Feedback to Decrease Ciprofloxacin Prescriptions in Patients with Acute Uncomplicated Cystitis

CONTEXT

Current guidelines recommend a nonfluoroquinolone agent as first-line treatment of acute uncomplicated cystitis (AUC) because of concerns of antimicrobial resistance and adverse effects.

OBJECTIVE

To test whether a multifaceted intervention involving education and feedback reduced primary care practitioners' ciprofloxacin prescriptions for AUC therapy.

DESIGN

Primary care practitioners at 3 medical offices participated: 65 in the intervention group and 51 in the control group. Intervention group participants received an educational lecture and emailed summary of antimicrobial guidelines, their AUC prescriptions were audited, and feedback was provided on inappropriate antibiotic choices. Prescriptions at AUC encounters were tracked during baseline, intervention, and postintervention periods.

MAIN OUTCOME MEASURES

Proportion of AUC encounters at which ciprofloxacin was prescribed vs recommended first-line antibiotics.

RESULTS

Intervention group participants had 5262 eligible AUC encounters, and control group participants had 5473. At baseline, ciprofloxacin was prescribed at 29.7% and 33.7% of eligible AUC encounters in the intervention and control groups, respectively (p = 0.003). After intervention, ciprofloxacin was prescribed at 10.8% of eligible AUC encounters in the intervention group and 34.3% in the control (p < 0.001). Adjusted odds ratios of ciprofloxacin prescription for AUC therapy were significantly lower in the intervention group during postintervention and intervention periods vs baseline (0.29, 95% confidence interval = 0.20-0.44, p < 0.001 and 0.80, 95% confidence interval = 0.66-0.97, p = 0.03). Adjusted odds ratios did not change over time in the controls.

CONCLUSION

Educating primary care practitioners and conducting audit and feedback reduced their prescriptions of ciprofloxacin for AUC therapy.

Medication class enrichment analysis: a novel algorithm to analyze multiple pharmacologic exposures simultaneously using electronic health record data

Objective

Observational studies analyzing multiple exposures simultaneously have been limited by difficulty distinguishing relevant results from chance associations due to poor specificity. Set-based methods have been successfully used in genomics to improve signal-to-noise ratio. We present and demonstrate medication class enrichment analysis (MCEA), a signal-to-noise enhancement algorithm for observational data inspired by set-based methods.

Materials and Methods

We used The Health Improvement Network database to study medications associated with Clostridium difficile infection (CDI). We performed case-control studies for each medication in The Health Improvement Network to obtain odds ratios (ORs) for association with CDI. We then calculated the association of each pharmacologic class with CDI using logistic regression and MCEA. We also performed simulation studies in which we assessed the sensitivity and specificity of logistic regression compared to MCEA for ORs 0.1-2.0.

Results

When analyzing pharmacologic classes using logistic regression, 47 of 110 pharmacologic classes were identified as associated with CDI. When analyzing pharmacologic classes using MCEA, only fluoroquinolones, a class of antibiotics with biologically confirmed causation, and heparin products were associated with CDI. In simulation, MCEA had superior specificity compared to logistic regression across all tested effect sizes and equal or better sensitivity for all effect sizes besides those close to null.

Discussion

Although these results demonstrate the promise of MCEA, additional studies that include inpatient administered medications are necessary for validation of the algorithm.

Conclusions

In clinical and simulation studies, MCEA demonstrated superior sensitivity and specificity for identifying pharmacologic classes associated with CDI compared to logistic regression.

Comparative Effectiveness of Exclusive Exposure to Nafcillin or Oxacillin, Cefazolin, Piperacillin/Tazobactam, and Fluoroquinolones Among a National Cohort of Veterans With Methicillin-Susceptible Staphylococcus aureus Bloodstream Infection

OBJECTIVE

Beta-lactam antibiotics are recommended as first-line for treatment of methicillin-sensitive Staphylococcus aureus (MSSA) bacteremia. The objective of this study was to compare effectiveness of anti-MSSA therapies among bacteremia patients exclusively exposed to 1 antimicrobial.

METHOD

This was a national retrospective cohort study of patients hospitalized in Veterans Affairs medical centers with MSSA bacteremia from January 1, 2002, to October 1, 2015. Patients were included if they were treated exclusively with nafcillin, oxacillin, cefazolin, piperacillin/tazobactam, or fluoroquinolones (moxifloxacin and levofloxacin). We assessed 30-day mortality, time to discharge, inpatient mortality, 30-day readmission, and 30-day S. aureus reinfection. Hazard ratios (HRs) and 95% confidence intervals (CI) were calculated using propensity-score (PS) matched Cox proportional hazards regression model.

RESULTS

When comparing nafcillin/oxacillin (n = 105) with cefazolin (n = 107), 30-day mortality was similar between groups (PS matched n = 44; HR, 0.67; 95% CI, 0.11-4.00), as were rates of the other outcomes assessed. As clinical outcomes did not vary between nafcillin/oxacillin and cefazolin, they were combined for comparison with piperacillin/tazobactam (n = 113) and fluoroquinolones (n = 103). Mortality in the 30 days after culture was significantly lower in the nafcillin/oxacillin/cefazolin group compared with piperacillin/tazobactam (PS matched n = 48; HR, 0.10; 95% CI, 0.01-0.78), and similar when compared with fluoroquinolones (PS matched n = 32; HR, 1.33; 95% CI, 0.30-5.96).

CONCLUSIONS

In hospitalized patients with MSSA bacteremia, no difference in mortality was observed between nafcillin/oxacillin and cefazolin or fluoroquinolones. However, higher mortality was observed with piperacillin/tazobactam as compared with nafcillin/oxacillin/cefazolin, suggesting it may not be as effective as a monotherapy in MSSA bacteremia.

Incidence, Risk Factors, and Outcomes of Clostridium difficile Infections in Kidney Transplant Recipients

BACKGROUND

Kidney transplant recipients (KTR) may be at increased risk for Clostridium difficile infections (CDI) but risk factors and outcomes in this population have not been well studied.

METHODS

An observational cohort study was conducted to determine the incidence, risk factors, and outcomes of CDI in KTR. A total of 1816 KTR transplanted between 2000 and 2013 at the Toronto General Hospital were included. Sixty-eight patients developed CDI. Controls were selected at a 4:1 ratio using risk-set sampling, and risk factors were explored using conditional logistic regression models. The impact of CDI on graft outcomes was evaluated using Cox proportional hazards models.

RESULTS

The incidence rate of CDI was 0.64 cases/100 person-years. Independent predictors of CDI included antibiotic use (odds ratio [OR], 2.88; 95% confidence interval [CI], 1.35-6.15), increased duration of hospitalization posttransplant (OR, 1.04; 95% CI, 1.02-1.06]), receiving a deceased donor kidney (OR, 2.98; 95% CI, 1.47-6.05), and a history of biopsy-proven acute rejection (OR, 5.82; 95% CI, 2.22-15.26). In the Cox proportional hazards model, CDI was found to be an independent risk factor for the subsequent development of biopsy-proven acute rejection (hazard ratio, 2.18; 95% CI, 1.34-3.55).

CONCLUSIONS

Our results confirm that transplant-specific factors place KTR at a higher risk for CDI. Clostridium difficile infections may increase the risk of adverse outcomes, such as biopsy-proven acute rejection. These findings emphasize the importance of preventive strategies to reduce the morbidity associated with CDI in KTR.

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.

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.

Guidelines for Antibiotic Prescription in Intensive Care Unit

How to cite this article: Khilnani GC, Zirpe K, Hadda V, Mehta Y, Madan K, Kulkarni A, Mohan A, Dixit S, Guleria R, Bhattacharya P. Guidelines for Antibiotic Prescription in Intensive Care Unit. Indian Journal of Critical Care Medicine 2019;23 (Suppl 1):1-63.

Predictors of Mortality Among a National Cohort of Veterans With Recurrent Clostridium difficile Infection

BACKGROUND

Though recurrent Clostridium difficile infection (CDI) is common and poses a major clinical concern, data are lacking regarding mortality among patients who survive their initial CDI and have subsequent recurrences. Risk factors for mortality in patients with recurrent CDI are largely unknown.

METHODS

Veterans Affairs patients with a first CDI (stool sample with positive C. difficile toxin(s) and ≥2 days CDI treatment) were included (2010-2014). Subsequent recurrences were defined as additional CDI episodes ≥14 days after the stool test date and within 30 days of the end of treatment. A matched (1:4) case-control analysis was conducted using multivariable conditional logistic regression to identify predictors of all-cause mortality within 30 days of the first recurrence.

RESULTS

Crude 30-day all-cause mortality rates were 10.6% for the initial CDI episode, 8.3% for the first recurrence, 4.2% for the second recurrence, and 5.9% for the third recurrence. Among 110 cases and 440 controls, 6 predictors of mortality were identified: use of proton pump inhibitors (PPIs; odds ratio [OR], 3.86; 95% confidence interval [CI], 2.14-6.96), any antibiotic (OR, 3.33; 95% CI, 1.79-6.17), respiratory failure (OR, 8.26; 95% CI, 1.71-39.92), congitive dysfunction (OR, 2.41; 95% CI, 1.02-5.72), nutrition deficiency (OR, 2.91; 95% CI, 1.37-6.21), and age (OR, 1.04; 95% CI, 1.01-1.07).

CONCLUSIONS

In our national cohort of Veterans, crude mortality decreased by 44% from the initial episode to the third recurrence. Treatment with antibiotics, use of PPIs, and underlying comorbidities were important predictors of mortality in recurrent CDI. Our study assists health care providers in identifying patients at high risk of death after CDI recurrence.

Clostridium difficile - From Colonization to Infection

Clostridium difficile is the most frequent cause of nosocomial antibiotic-associated diarrhea. The incidence of C. difficile infection (CDI) has been rising worldwide with subsequent increases in morbidity, mortality, and health care costs. Asymptomatic colonization with C. difficile is common and a high prevalence has been found in specific cohorts, e.g., hospitalized patients, adults in nursing homes and in infants. However, the risk of infection with C. difficile differs significantly between these cohorts. While CDI is a clear indication for therapy, colonization with C. difficile is not believed to be a direct precursor for CDI and therefore does not require treatment. Antibiotic therapy causes alterations of the intestinal microbial composition, enabling C. difficile colonization and consecutive toxin production leading to disruption of the colonic epithelial cells. Clinical symptoms of CDI range from mild diarrhea to potentially life-threatening conditions like pseudomembranous colitis or toxic megacolon. While antibiotics are still the treatment of choice for CDI, new therapies have emerged in recent years such as antibodies against C. difficile toxin B and fecal microbial transfer (FMT). This specific therapy for CDI underscores the role of the indigenous bacterial composition in the prevention of the disease in healthy individuals and its role in the pathogenesis after alteration by antibiotic treatment. In addition to the pathogenesis of CDI, this review focuses on the colonization of C. difficile in the human gut and factors promoting CDI.

Clostridium difficile - From Colonization to Infection

Clostridium difficile is the most frequent cause of nosocomial antibiotic-associated diarrhea. The incidence of C. difficile infection (CDI) has been rising worldwide with subsequent increases in morbidity, mortality, and health care costs. Asymptomatic colonization with C. difficile is common and a high prevalence has been found in specific cohorts, e.g., hospitalized patients, adults in nursing homes and in infants. However, the risk of infection with C. difficile differs significantly between these cohorts. While CDI is a clear indication for therapy, colonization with C. difficile is not believed to be a direct precursor for CDI and therefore does not require treatment. Antibiotic therapy causes alterations of the intestinal microbial composition, enabling C. difficile colonization and consecutive toxin production leading to disruption of the colonic epithelial cells. Clinical symptoms of CDI range from mild diarrhea to potentially life-threatening conditions like pseudomembranous colitis or toxic megacolon. While antibiotics are still the treatment of choice for CDI, new therapies have emerged in recent years such as antibodies against C. difficile toxin B and fecal microbial transfer (FMT). This specific therapy for CDI underscores the role of the indigenous bacterial composition in the prevention of the disease in healthy individuals and its role in the pathogenesis after alteration by antibiotic treatment. In addition to the pathogenesis of CDI, this review focuses on the colonization of C. difficile in the human gut and factors promoting CDI.

Antibiotic Therapy for Acute Watery Diarrhea and Dysentery

Diarrheal disease affects a large proportion of military personnel deployed to developing countries, resulting in decreased job performance and operational readiness. Travelers' diarrhea is self-limiting and generally resolves within 5 days; however, antibiotic treatment significantly reduces symptom severity and duration of illness. Presently, azithromycin is the preferred first-line antibiotic for the treatment of acute watery diarrhea (single dose 500 mg), as well as for febrile diarrhea and dysentery (single dose 1,000 mg). Levofloxacin and ciprofloxacin are also options for acute watery diarrhea (single dose 500 mg and 750 mg, respectively) and febrile diarrhea/dysentery in areas with high rates of Shigella (500 mg once for 3 days [once daily with levofloxacin and twice daily with ciprofloxacin]), but are becoming less effective because of increasing fluoroquinolone resistance, particularly among Campylobacter spp. Another alternate for acute watery diarrhea is rifaximin (200 mg 3 times per day for 3 days); however, it should not be used with invasive illness. Use of loperamide in combination with antibiotic treatment is also beneficial as it has been shown to further reduce gastrointestinal symptoms and duration of illness. Because of regional differences in the predominance of pathogens and resistance levels, choice of antibiotic should take travel destination into consideration.

Spectrum and antibiotic resistance of uropathogens between 2004 and 2015 in a tertiary care hospital in Hungary

PURPOSE

Surveillance of the bacterial spectrum and antibiotic-resistance patterns of locally occurring uropathogens is essential to serve as a basis for empirical treatment of urinary tract infections (UTIs), as antibiotic-resistance rates may vary geographically with significant differences between countries and regions, and with time.

METHODOLOGY

We retrospectively analysed all urine samples taken in the department of urology in a tertiary care hospital in Hungary from January 2004 to December 2015.Results/Key findings. The five most commonly occurring bacteria were Escherichia coli, Enterococcus faecalis, Klebsiella pneumoniae, Pseudomonas aeruginosa and Proteus mirabilis. Resistance of Escherichia coli to ciprofloxacin increased significantly from 19 to 25 %. Although the resistance of Escherichia coli against cephalosporins showed an increasing trend, it still remained generally low. However, resistance rates of K. pneumoniae to cephalosporins were very high, reaching 60 %, due to the high rate of extended-spectrum-β-lactamase-positive Klebsiella strains. We observed a significant increase in the rate of carbapenem-resistant Pseudomonas aeruginosa.

CONCLUSION

Fluoroquinolones cannot be recommended for empirical treatment in our region. Cephalosporins can be a good empirical choice for treating Gram-negative UTIs, but should be avoided when multi-drug resistant (MDR) bacteria are suspected. Increases in the rate of carbapenem-resistant Pseudomonas aeruginosa, and in the general rate of MDR bacteria, are both a very alarming trend. We recommend practising prudent antibiotic policy, preferably using antibiotics with the narrowest possible spectrum.

Effect of a Health Care System Respiratory Fluoroquinolone Restriction Program To Alter Utilization and Impact Rates of Clostridium difficile Infection

Fluoroquinolones are one of the most commonly prescribed antibiotic classes in the United States despite their association with adverse consequences, including Clostridium difficile infection (CDI). We sought to evaluate the impact of a health care system antimicrobial stewardship-initiated respiratory fluoroquinolone restriction program on utilization, appropriateness of quinolone-based therapy based on institutional guidelines, and CDI rates. After implementation, respiratory fluoroquinolone utilization decreased from a monthly mean and standard deviation (SD) of 41.0 (SD = 4.4) days of therapy (DOT) per 1,000 patient days (PD) preintervention to 21.5 (SD = 6.4) DOT/1,000 PD and 4.8 (SD = 3.6) DOT/1,000 PD posteducation and postrestriction, respectively. Using segmented regression analysis, both education (14.5 DOT/1,000 PD per month decrease; P = 0.023) and restriction (24.5 DOT/1,000 PD per month decrease; P < 0.0001) were associated with decreased utilization. In addition, the CDI rates decreased significantly (P = 0.044) from preintervention using education (3.43 cases/10,000 PD) and restriction (2.2 cases/10,000 PD). Mean monthly CDI cases/10,000 PD decreased from 4.0 (SD = 2.1) preintervention to 2.2 (SD = 1.35) postrestriction. A significant increase in appropriate respiratory fluoroquinolone use occurred postrestriction versus preintervention in patients administered at least one dose (74/130 [57%] versus 74/232 [32%]; P < 0.001), as well as in those receiving two or more doses (47/65 [72%] versus 67/191 [35%]; P < 0.001). A significant reduction in the annual acquisition cost of moxifloxacin, the formulary respiratory fluoroquinolone, was observed postrestriction compared to preintervention within the health care system ($123,882 versus $12,273; P = 0.002). Implementation of a stewardship-initiated respiratory fluoroquinolone restriction program can increase appropriate use while reducing overall utilization, acquisition cost, and CDI rates within a health care system.

Current Trends in the Epidemiology and Outcomes of Clostridium difficile Infection

Clostridium difficile is the most frequently identified cause of nosocomial diarrhea and has been associated with epidemics of diarrhea in hospitals and long-term care facilities. The continued increase in C. difficile infection (CDI) suggests that it has surpassed other pathogens in causing healthcare-associated infections. The Centers for Disease Control and Prevention recently identified CDI as an "urgent threat" in its recent report on antibiotic resistance threats in the United States, highlighting the need for urgent and aggressive action to prevent this infection. The impact of antibiotics as a risk factor for new-onset CDI is well established; however, recognizing classes of antibiotics with the highest risks and reducing unnecessary antibiotic use are important strategies for prevention of CDI and subsequent recurrence. In addition, the recognition of the community as an important setting for onset of CDI presents a challenge and is an area for future research.

Antimicrobials: a global alliance for optimizing their rational use in intra-abdominal infections (AGORA)

Intra-abdominal infections (IAI) are an important cause of morbidity and are frequently associated with poor prognosis, particularly in high-risk patients. The cornerstones in the management of complicated IAIs are timely effective source control with appropriate antimicrobial therapy. Empiric antimicrobial therapy is important in the management of intra-abdominal infections and must be broad enough to cover all likely organisms because inappropriate initial antimicrobial therapy is associated with poor patient outcomes and the development of bacterial resistance. The overuse of antimicrobials is widely accepted as a major driver of some emerging infections (such as C. difficile), the selection of resistant pathogens in individual patients, and for the continued development of antimicrobial resistance globally. The growing emergence of multi-drug resistant organisms and the limited development of new agents available to counteract them have caused an impending crisis with alarming implications, especially with regards to Gram-negative bacteria. An international task force from 79 different countries has joined this project by sharing a document on the rational use of antimicrobials for patients with IAIs. The project has been termed AGORA (Antimicrobials: A Global Alliance for Optimizing their Rational Use in Intra-Abdominal Infections). The authors hope that AGORA, involving many of the world's leading experts, can actively raise awareness in health workers and can improve prescribing behavior in treating IAIs.

A Comprehensive Assessment Across the Healthcare Continuum: Risk of Hospital-Associated Clostridium difficile Infection Due to Outpatient and Inpatient Antibiotic Exposure

BACKGROUND

Limitations in sample size, overly inclusive antibiotic classes, lack of adjustment of key risk variables, and inadequate assessment of cases contribute to widely ranging estimates of risk factors for Clostridium difficile infection (CDI).

OBJECTIVE

To incorporate all key CDI risk factors in addition to 27 antibiotic classes into a single comprehensive model.

DESIGN

Retrospective cohort study.

SETTING

Kaiser Permanente Southern California.

PATIENTS

Members of Kaiser Permanente Southern California at least 18 years old admitted to any of its 14 hospitals from January 1, 2011, through December 31, 2012.

METHODS

Hospital-acquired CDI cases were identified by polymerase chain reaction assay. Exposure to major outpatient antibiotics (10 classes) and those administered during inpatient stays (27 classes) was assessed. Age, sex, self-identified race/ethnicity, Charlson Comorbidity Score, previous hospitalization, transfer from a skilled nursing facility, number of different antibiotic classes, statin use, and proton pump inhibitor use were also assessed. Poisson regression estimated adjusted risk of CDI.

RESULTS

A total of 401,234 patients with 2,638 cases of incident CDI (0.7%) were detected. The final model demonstrated highest CDI risk associated with increasing age, exposure to multiple antibiotic classes, and skilled nursing facility transfer. Factors conferring the most reduced CDI risk were inpatient exposure to tetracyclines and first-generation cephalosporins, and outpatient macrolides. CONCLUSIONS Although type and aggregate antibiotic exposure are important, the factors that increase the likelihood of environmental spore acquisition should not be underestimated. Operationally, our findings have implications for antibiotic stewardship efforts and can inform empirical and culture-driven treatment approaches.

CLINICAL AND EPIDEMIOLOGIC CONSIDERATIONS OF CLOSTRIDIUM DIFFICILE IN HARBOR SEALS (PHOCA VITULINA) AT A MARINE MAMMAL REHABILITATION CENTER

Between 1998 and 2008, 15 cases of segmental to diffuse hemorrhagic to necrohemorrhagic enterocolitis were diagnosed in neonatal and weaned juvenile harbor seals (Phoca vitulina) presented from the Vancouver Aquarium Marine Mammal Rescue Centre for rehabilitation. Based on a combination of gross pathology, histopathology, bacterial isolation, and toxin testing, Clostridium difficile enterocolitis was diagnosed. Most pups were anorexic or inappetant and died acutely with few other premonitory signs. Due to ongoing clinical concerns and possible emergence of this pathogen at the facility, efforts to better characterize the disease and understand the epidemiology of C. difficile was initiated in 95 harbor seal pups presented for rehabilitation in a single stranding season. Fecal samples were collected on admission, following completion of antibiotic treatment, and also prerelease or postmortem. All samples were collected fresh and submitted either directly or stored frozen. Fecal samples were inoculated into selective media for culture and screened by enzyme-linked immunosorbant assay (ELISA) for C. difficile toxins A, B, or both. Results of the 95 seals in the study were as follows: on hospital admit 72 seals were sampled, 10 were culture positive, 12 were ELISA positive; following antibiotic therapy 46 seals were sampled noting three culture positive and nine ELISA positive; prior to release 58 seals were sampled noting zero culture positive and one ELISA positive; and on postmortem exam seven seals were sampled noting zero culture positive and two ELISA positive. Clostridium difficile was not deemed to be the cause of death in any of the animals. Although the exact mechanism of disease is unknown, this study suggests that C. difficile infection is not a significant cause of mortality and may be part of the normal flora in harbor seals undergoing rehabilitation. Morbidity and mortality from this bacterium can likely be minimized by judicious use of antibiotics, effective biosecurity-biocontainment protocols, and clean husbandry practices.

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.

Effects of fluoroquinolone restriction (from 2007 to 2012) on Clostridium difficile infections: interrupted time-series analysis

BACKGROUND

Antimicrobial stewardship is a key component in the reduction of healthcare-associated infections, particularly Clostridium difficile infection (CDI). We successfully restricted the use of cephalosporins and, subsequently, fluoroquinolones. From an endemically high level of >280 cases per year in 2007-08, the number of CDIs reduced to 72 cases in 2011-12.

AIM

To describe the implementation and impact of fluoroquinolone restriction on CDI.

METHODS

This was an interrupted time-series analysis pre and post fluoroquinolone restriction for 60 months based on a Poisson distribution model.

FINDINGS

In June 2008, fluoroquinolone consumption halved to about 5 defined daily doses (DDD) per 100 occupied bed-days (OBD). This was followed by a significant fall in CDI number [rate ratio (RR): 0.332; 95% confidence interval (CI): 0.240-0.460] which remained low over the subsequent months. Subsequently, fluoroquinolone consumption was further reduced to about 2 DDD/100 OBD in June 2010 accompanied by further reduction in CDI rate (RR: 0.394; 95% CI: 0.199-0.781). In a univariate Poisson model the CDI rate was associated with fluoroquinolone usage (RR: 1.086; 95% CI: 1.077-1.094).

CONCLUSION

We conclude that in an environment where cephalosporin usage is already low, the reduction in fluoroquinolone usage was associated with an immediate, large, and significant reduction in CDI cases.

Doxycycline and Tigecycline: Two Friendly Drugs with a Low Association with Clostridium Difficile Infection

Clostridium difficile infection (CDI) is known to be associated with prior exposure to many classes of antibiotics. Standard therapy for CDI (i.e., metronidazole and vancomycin) is associated with high recurrence rates. Although tetracycline derivatives such as tetracycline, doxycycline or tigecycline are not the standard therapeutic choices for CDI, they may serve as an alternative or a component of combination therapy. Previous tetracycline or doxycycline usage had been shown to have less association with CDI development. Tigecycline, a broad-spectrum glycylcycline with potency against many gram-positive or gram-negative pathogens, had been successfully used to treat severe or refractory CDI. The in vitro susceptibility of C. difficile clinical isolates to tigecycline in many studies showed low minimal inhibitory concentrations. Tigecycline can suppress in vitro toxin production in both historical and hypervirulent C. difficile strains and reduce spore production in a dose-dependent manner. Tetracycline compounds such as doxycycline, minocycline, and tigecycline possess anti-inflammatory properties that are independent of their antibiotic activity and may contribute to their therapeutic effect for CDI. Although clinical data are limited, doxycycline is less likely to induce CDI, and tigecycline can be considered one of the therapeutic choices for severe or refractory CDI.

Association between Clostridium difficile infection and antimicrobial usage in a large group of English hospitals

AIMS

This study aimed to determine the association between the reduction in the number of Clostridium difficile infection (CDI) cases reported by the English National Health Service (NHS) hospitals and concurrent antimicrobial use.

METHODS

A retrospective ecological study for January 2005 to December 2008 was conducted using data from 26 of the 29 NHS trusts (i.e. a trust manages one or more hospitals) located in the North West Strategic Health Authority of England. Antimicrobial use data, for patients of all ages, were provided by IMS Health, and CDI case data for patients aged ≥65 years were provided by the Health Protection Agency. Antimicrobial use was converted into defined daily doses (DDDs). The overall association between antimicrobial use and CDI for the trusts was investigated using multilevel models.

RESULTS

Our study shows a positive significant association between the CDI cases and the use of the following antimicrobials: ‘third-generation cephalosporins’ [11.62 CDI cases per 1000 DDDs; 95% confidence interval (CI), 5.92–17.31]; ‘fluoroquinolones’ (4.79 CDI cases per 1000 DDDs; 95% CI, 2.83–6.74); and ‘second-generation cephalosporins’ (4.25 CDI cases per 1000 DDDs; 95% CI, 1.66–6.83). The strength of this association was not significantly different (95% CI) among the antimicrobial groups.

CONCLUSIONS

This study shows that the reduction in the number of CDI cases reported by the English NHS hospitals is associated with concurrent reductions in antimicrobial use. This means that the number of CDI cases over time decreased in a similar fashion to the usage of various antimicrobials.

Evidence-based assessment of proton-pump inhibitors in Helicobacter pylori eradication: A systematic review

Peptic ulcer disease continues to be issue especially due to its high prevalence in the developing world. Helicobacter pylori (H. pylori) infection associated duodenal ulcers should undergo eradication therapy. There are many regimens offered for H. pylori eradication which include triple, quadruple, or sequential therapy regimens. The central aim of this systematic review is to evaluate the evidence for H. pylori therapy from a meta-analytical outlook. The consequence of the dose, type of proton-pump inhibitor, and the length of the treatment will be debated. The most important risk factor for eradication failure is resistance to clarithromycin and metronidazole.

A retrospective analysis of clinical characteristics, hospitalization, and functional outcomes in residents with and without Clostridium difficile infection in US long-term care facilities

OBJECTIVE

Patients in long-term care (LTC) are at increased risk for acquiring Clostridium difficile infection (CDI). We compared the characteristics and outcomes of matched cohorts with and without CDI in the LTC setting.

METHODS

Using a retrospective cohort design, demographic characteristics, Minimum Data Set (MDS 2.0) assessments (years 2007-2010), and pharmacy records of residents were analyzed. Residents were required to have a CDI diagnosis, ≥1 MDS 2.0 assessment ≤120 days pre- and post-index event, and receipt of metronidazole (MET) or vancomycin (VAN) within ±7 days of index date. Baseline characteristics were compared between cases and controls matched 1:3 on age, gender, and index year. Cox regression (CR) analysis evaluated the relationship between CDI status, and post-index mortality and hospitalization.

RESULTS

A total of 1145 CDI residents were matched with 3488 non-CDI residents. A second sample used propensity score methods. CDI vs. non-CDI residents had a higher baseline comorbidity burden (Charlson score: 3.0 ± 1.9 vs. 2.2 ± 1.8, respectively), and were more likely to have had a recent hospitalization (63% vs. 9%, respectively) and shorter mean pre-index continuous length of stay (cLOS) in the LTC (386.4 d ± 536.3 d vs. 568.3 d ± 567.4 d, respectively), all P < 0.0001. CR analyses of both samples indicated that CDI was strongly associated with shorter times to hospitalization and mortality (hazard ratio (HR) = 1.3, P = 0.023 and 2.2, P < 0.0001, respectively; propensity-matched group). Pre-index LTC cLOS also remained an important variable in the CR analysis and was the strongest predictor of post-index hospitalization and mortality (HR = 0.999 and 0.996, respectively, P < 0.0001), indicating that residents with longer pre-index LTC cLOS had longer times to post-index hospitalization and mortality. Our reliance on the MDS records for case identification was our chief limitation; misclassification was mitigated by our requirement to include CDI treatment as part of our inclusion criteria.

CONCLUSIONS

Understanding factors that put LTC patients at risk for CDI can help guide better management and improvement of patient outcomes.

Urinary Tract Infections: Leading Initiatives in Selecting Empiric Outpatient Treatment (UTILISE)

BACKGROUND

Overuse of fluoroquinolone antibiotics is associated with outbreaks of methicillin-resistant Staphylococcus aureus and of Clostridium difficile-associated diarrhea and increasing resistance in gram-negative organisms. Over the past decade, resistance of Escherichia coli to ciprofloxacin has increased in the Regina Qu'Appelle Health Region. In August 2011, an exploratory audit of the Regina General Hospital (RGH) emergency department showed that 20% of new antibiotic orders were for fluoroquinolones, and 60% of these new fluoroquinolone orders were for ciprofloxacin. It was postulated that ciprofloxacin was predominantly prescribed for outpatients with urinary tract infection.

OBJECTIVE

To develop, implement, and evaluate a best-practice algorithm for the empiric treatment of uncomplicated urinary tract infection in the RGH emergency department, as part of an educational initiative for emergency physicians.

METHODS

A literature review was conducted and local antibiogram data were analyzed to establish a best-practice algorithm for treatment of uncomplicated urinary tract infection in outpatients seen in the emergency department. A chart review was conducted from January to March 2011 to establish a baseline of empiric antibiotic use. An educational strategy targeting emergency physicians described changes in antibiotic resistance patterns in the health region, principles of antimicrobial stewardship, drivers of resistance, and the results of a literature review of best practice for urinary tract infection in outpatients. A post-intervention audit was conducted from January to March 2012 to determine changes in practice.

RESULTS

Comparison of results from the post-intervention audit with baseline data showed that adherence to best practice increased significantly, from 41% (39/96) before the intervention to 66% (50/76) after the intervention (odds ratio [OR] 2.81, 95% confidence interval [CI] 1.51-5.25; p < 0.001). There was also a significant change in overall antibiotic selection (OR 0.25, 95% CI 0.11-0.58; p < 0.001). Further analysis suggested that this significant change was driven by a decrease in use of ciprofloxacin, from 32% (31/96) to 11% (8/76).

CONCLUSION

Creation of a best-practice algorithm and education focused on emergency physicians significantly increased adherence to best practice and optimized antibiotic prescribing for outpatients with uncomplicated urinary tract infection by limiting overuse of fluoroquinolones, primarily ciprofloxacin.

Irrational antibiotic prescribing: a local issue or global concern?

Resistance to antibiotics is a major public-health concern and antibiotic use is being ever more recognized as the main discriminatory pressure driving this resistance. The aim was to assess the outpatient usage of antibiotics in teaching hospitals in various parts of capital city of Iran, Tehran and its association with resistance. 600 outpatient antibiotic prescriptions between December 2011 and May 2012 were reviewed in our teaching hospitals. All prescriptions were scrutinized in order to evaluate the antibiotic prescribing. The medical doctors from all grades were asked to note the chief complaints and the most possible diagnosis on each prescription. Clinical data, patient demographic and ultimately the total quantities of antibiotics were recorded. Our data was then compared against the major antibiotic guidelines and similar studies in other countries. The most common prescribed antibiotics are Penicillins (Penicillin, Co-Amoxiclav and Amoxicillin) (40 %), Cephalosporins (Cefixime, Cephalexin and Ceftriaxone) (24.5 %) and Macrolides (particularly Azithromycin) (15.3 %). In total, 18.2 % of cases were combinational antibacterial therapies (≥ 2). The most common diagnosis was upper respiratory tract infections as common cold (29.2 %) and sore throat (11.8 %). Directions (instructions for use) of 58 % of selected antibiotics were acceptable. Parenteral administration remains the common route of administration with 22 % of all reviewed prescriptions. Based on Cochrane reviews the antibiotic prescribing was unjustified in 42.7 % of the cases. The prescribing habit, correct diagnosis and the use of antibiotics need instant consideration. These data can provide useful information for assessing public-health policy that aims to reduce the antibiotic use and resistance levels.

Randomized, double-blind, multicenter phase 2 study comparing the efficacy and safety of oral solithromycin (CEM-101) to those of oral levofloxacin in the treatment of patients with community-acquired bacterial pneumonia

Solithromycin, a new macrolide, and the first fluoroketolide in clinical development, with activity against macrolide-resistant bacteria, was tested in 132 patients with moderate to moderately severe community-acquired bacterial pneumonia (CABP) in a multicenter, double-blind, randomized phase 2 study. Patients were enrolled and randomized (1:1) to either 800 mg solithromycin orally (PO) on day 1, followed by 400 mg PO daily on days 2 to 5, or 750 mg levofloxacin PO daily on days 1 to 5. Efficacy outcome rates of clinical success at the test-of-cure visit 4 to 11 days after the last dose of study drug were comparable in the intent-to-treat (ITT) (84.6% for solithromycin versus 86.6% for levofloxacin) and microbiological-intent-to-treat (micro-ITT) (77.8% for solithromycin versus 71.4% for levofloxacin) populations. Early response success rates at day 3, defined as improvement in at least two cardinal symptoms of pneumonia, were also comparable (72.3% for solithromycin versus 71.6% for levofloxacin). More patients treated with levofloxacin than with solithromycin experienced treatment-emergent adverse events (TEAEs) during the study (45.6% versus 29.7%). The majority of TEAEs were mild or moderate gastrointestinal symptoms and included nausea (1.6% for solithromycin; 10.3% for levofloxacin), diarrhea (7.8% for solithromycin; 5.9% for levofloxacin), and vomiting (0% for solithromycin; 4.4% for levofloxacin). Six patients, all of whom received levofloxacin, discontinued the study drug due to an adverse event. Solithromycin demonstrated comparable efficacy and favorable safety relative to levofloxacin. These findings support a phase 3 study of solithromycin for the treatment of CABP. (This study has been registered at ClinicalTrials.gov under registration no. NCT01168713.).