Burden Of Clostridium Difficile Infection Research Articles

Burden of Clostridium difficile Infection (CDI) Across Hospital Inpatient, Nursing Home, and Home Settings

Burden of Clostridium difficile Infection (CDI) Across Hospital Inpatient, Nursing Home, and Home Settings

Burden of Clostridium difficile Infection in Long-Term Care Facilities in Bernalillo County

Burden of Clostridium difficile Infection in Long-Term Care Facilities in Bernalillo County

Clostridium difficile in an Urban, University-Affiliated Long-Term Acute Care Hospital

OBJECTIVES To describe the characteristics and impact of Clostridium difficile infection (CDI) in a long-term acute-care hospital (LTACH). DESIGN Retrospective matched cohort study. SETTING A 38-bed, urban, university-affiliated LTACH. METHODS The characteristics of LTACH-onset CDI were assessed among patients hospitalized between July 2008 and October 2015. Patients with CDI were matched to concurrently hospitalized patients without a diagnosis of CDI. Severe CDI was defined as CDI with 2 or more of the following criteria: age ≥65 years, serum creatinine ≥2 mg/dL, or peripheral leukocyte count ≥20,000 cells/μL. A conditional Poisson regression model was developed to determine characteristics associated with a composite primary outcome of 30-day readmission to an acute-care hospital, or mortality. RESULTS The overall incidence of CDI was 21.4 cases per 10,000 patient days, with 27% of infections classified as severe. Patients with CDI had a mean age of 70 years (SD, 14 years), a mean Charlson comorbidity index of 3.6 (SD, 2.0), a median length of stay of 33 days (interquartile range [IQR], 24–45 days), and a median time between admission and CDI diagnosis of 16 days (IQR, 9–23 days). The most commonly prescribed antibiotic preceding a CDI diagnosis was a cephalosporin, with median duration of 8 days (IQR, 4–14 days). In multivariate analysis, CDI was not significantly associated with the primary outcome (relative risk, 0.97; 95% CI, 0.59–1.58). CONCLUSIONS Incidence of CDI in an urban, university-affiliated LTACH was high. Future research should focus on infection prevention measures to decrease the burden of CDI in this complex patient population. Infect Control Hosp Epidemiol 2017;38:294–299

Clostridium difficile: A healthcare-associated infection of unknown significance in adults in sub-Saharan Africa.

Clostridium difficile infection (CDI) causes a high burden of disease in high-resource healthcare systems, with significant morbidity, mortality, and financial implications. CDI is a healthcare-associated infection for which the primary risk factor is antibiotic usage, and it is the leading cause of bacterial diarrhoea in HIV-infected patients in the United States. Little is known about the disease burden of CDI in sub-Saharan Africa, where HIV and healthcare-associated infections are more prevalent and antibiotic usage is less restricted. This article reviews published literature on CDI in sub-Saharan Africa, highlighting areas for future research. English language publications since 1995 were identified from online databases (PubMed, Medline, Google Scholar, and SCOPUS), using combinations of keywords "C. difficile", "Africa", and "HIV". Ten relevant studies were identified. There was considerable variation in the methodologies used to assess for carriage of toxigenic C. difficile and its associations. Eight studies reported carriage of toxigenic C. difficile. Three (of three) studies found an association with antibiotic usage. One (of four) studies showed an association with HIV infection. One study showed no association with degree of immunosuppression in HIV. Two (of three) studies showed an association between carriage of toxigenic C. difficile and diarrhoeal illness. While the carriage of toxigenic C. difficile is well described in sub-Saharan Africa, the impact of CDI in the region remains poorly understood and warrants further research.

Epidemiological and economic burden of Clostridium difficile in the United States: estimates from a modeling approach.

BackgroundDespite a large increase in Clostridium difficile infection (CDI) severity, morbidity and mortality in the US since the early 2000s, CDI burden estimates have had limited generalizability and comparability due to widely varying clinical settings, populations, or study designs.MethodsA decision-analytic model incorporating key input parameters important in CDI epidemiology was developed to estimate the annual number of initial and recurrent CDI cases, attributable and all-cause deaths, economic burden in the general population, and specific number of high-risk patients in different healthcare settings and the community in the US. Economic burden was calculated adopting a societal perspective using a bottom-up approach that identified healthcare resources consumed in the management of CDI.ResultsAnnually, a total of 606,058 (439,237 initial and 166,821 recurrent) episodes of CDI were predicted in 2014: 34.3 % arose from community exposure. Over 44,500 CDI-attributable deaths in 2014 were estimated to occur. High-risk susceptible individuals representing 5 % of the total hospital population accounted for 23 % of hospitalized CDI patients. The economic cost of CDI was $5.4 billion ($4.7 billion (86.7 %) in healthcare settings; $725 million (13.3 %) in the community), mostly due to hospitalization.ConclusionsA modeling framework provides more comprehensive and detailed national-level estimates of CDI cases, recurrences, deaths and cost in different patient groups than currently available from separate individual studies. As new treatments for CDI are developed, this model can provide reliable estimates to better focus healthcare resources to those specific age-groups, risk-groups, and care settings in the US where they are most needed. (Trial Identifier ClinicaTrials.gov: NCT01241552)Electronic supplementary materialThe online version of this article (doi:10.1186/s12879-016-1610-3) contains supplementary material, which is available to authorized users.

Risk factors associated with interfacility transfers among patients with Clostridium difficile infection

Preventing the transmission of Clostridium difficile infection (CDI) over the continuum of care presents an important challenge for infection control. A prospective case-control study was conducted on patients admitted with CDI to a tertiary care hospital in Detroit between August 2012 and September 2013. Patients were then followed for 1 year by telephone interviews and the hospital administrative database. Cases, patients with interfacility transfers (IFTs), were patients admitted to our facility from another health care facility and discharged to long-term care (LTC) facilities. Controls were patients admitted from and discharged to home. There were 143 patients included in the study. Thirty-six (30%) cases were compared with 84 (70%) controls. Independent risk factors of CDI patients with IFTs (compared with CDI patients without IFTs) included Charlson Comorbidity Index score ≥6 (odds ratio [OR], 5.30; P = .016) and hospital-acquired CDI (OR, 4.92; P = .023). Patients with IFTs were more likely to be readmitted within 90 days of discharge than patients without IFTs (OR, 2.24; P = .046). One-year mortality rate was significantly higher among patients with IFTs than among patients without IFTs (OR, 4.33; P = .01). With the growing number of alternate health care centers, it is highly critical to establish better collaboration between acute care and LTC facilities to tackle the increasing burden of CDI across the health care system.

Burden of Clostridium difficile Infections in Québec by Levy et al.

To the Editor—We read with great interest the article on the incidence and cost of Clostridium difficile infections (CDIs) in Canada by Levy et al [1]. This study provides valuable information, because little data exist on the burden associated with CDI in Canada. However, we would like to draw attention to the fact that the number of cases that occur every year in the province of Quebec has been overestimated more than 2-fold. In their study, Levy et al [1] estimated that 16 562 CDI cases occur in Quebec every year. This number is extrapolated from data of the Canadian Nosocomial Infection Surveillance Program (CNISP) [2]. Much more comprehensive data exist regarding CDI in Quebec that could have been used to draw a more accurate picture of the situation. Our province has implemented a mandatory CDI surveillance program in 2004 in the wake of the NAP1 epidemic [3]. Ninety-five acute-care institutions representing 99% of all patient admissions have the obligation to participate in this surveillance program conducted by the Institut National de Sante Publique du Quebec. Results are published in yearly reports and are publicly available [4]. Hospitals are subjected to government-imposed targets that are risk stratified according to hospital size, patient population, and academic mission [5]. Based on these official surveillance data, approximately 3700 primary hospital-associated CDI cases occurred every year in Quebec between 2010 and 2013, for a global incidence of approximately 7.0 per 10 000 patient-days. Using the authors' assumptions and calculation methods to estimate the number of community-acquired cases and the number of recurrences (which are not part of our surveillance program), approximately 7400 CDI cases occurs in this province each year, less than half the number of cases estimated by the authors and less than the province of Ontario. Their overestimation is probably due to sampling bias. Only 8 institutions in Quebec participate in the CNISP surveillance program, the source of data used by the authors to estimate the CDI burden in the province. Most of these hospitals are large academic institutions with intrinsically high CDI incidence. Inferring provincial data from these few hospitals has led to a sizeable overestimation of the true burden of CDI in the province. The impact of this overestimation on the conclusions of the study should be carefully addressed.

The burden of clostridium difficile infection: estimates of the incidence of CDI from U.S. Administrative databases.

BackgroundMany administrative data sources are available to study the epidemiology of infectious diseases, including Clostridium difficile infection (CDI), but few publications have compared CDI event rates across databases using similar methodology. We used comparable methods with multiple administrative databases to compare the incidence of CDI in older and younger persons in the United States.MethodsWe performed a retrospective study using three longitudinal data sources (Medicare, OptumInsight LabRx, and Healthcare Cost and Utilization Project State Inpatient Database (SID)), and two hospital encounter-level data sources (Nationwide Inpatient Sample (NIS) and Premier Perspective database) to identify CDI in adults aged 18 and older with calculation of CDI incidence rates/100,000 person-years of observation (pyo) and CDI categorization (onset and association).ResultsThe incidence of CDI ranged from 66/100,000 in persons under 65 years (LabRx), 383/100,000 in elderly persons (SID), and 677/100,000 in elderly persons (Medicare). Ninety percent of CDI episodes in the LabRx population were characterized as community-onset compared to 41 % in the Medicare population. The majority of CDI episodes in the Medicare and LabRx databases were identified based on only a CDI diagnosis, whereas almost ¾ of encounters coded for CDI in the Premier hospital data were confirmed with a positive test result plus treatment with metronidazole or oral vancomycin. Using only the Medicare inpatient data to calculate encounter-level CDI events resulted in 553 CDI events/100,000 persons, virtually the same as the encounter proportion calculated using the NIS (544/100,000 persons).ConclusionsWe found that the incidence of CDI was 35 % higher in the Medicare data and fewer episodes were attributed to hospital acquisition when all medical claims were used to identify CDI, compared to only inpatient data lacking information on diagnosis and treatment in the outpatient setting. The incidence of CDI was 10-fold lower and the proportion of community-onset CDI was much higher in the privately insured younger LabRx population compared to the elderly Medicare population. The methods we developed to identify incident CDI can be used by other investigators to study the incidence of other infectious diseases and adverse events using large generalizable administrative datasets.Electronic supplementary materialThe online version of this article (doi:10.1186/s12879-016-1501-7) contains supplementary material, which is available to authorized users.

Recent Advances in the Diagnosis and Treatment of Clostridium Difficile Infection.

Clostridium difficile infection (CDI) has become the most frequently reported health care-associated infection in the United States [1]. As the incidence of CDI rises, so too does the burden it produces on health care and society. In an attempt to decrease the burden of CDI and provide the best outcomes for patients affected by CDI, there have been many recent advancements in the understanding, diagnosis, and management of CDI. In this article, we review the current recommendations regarding CDI testing and treatment strategies.

Burden of Nursing Home-Onset Clostridium difficile Infection in the United States: Estimates of Incidence and Patient Outcomes.

Background. Approximately 4 million Americans receive nursing home (NH) care annually. Nursing home residents commonly have risk factors for Clostridium difficile infection (CDI), including advanced age and antibiotic exposures. We estimated national incidence of NH-onset (NHO) CDI and patient outcomes.Methods. We identified NHO-CDI cases from population-based surveillance of 10 geographic areas in the United States. Cases were defined by C difficile-positive stool collected in an NH (or from NH residents in outpatient settings or ≤3 days after hospital admission) without a positive stool in the prior 8 weeks. Medical records were reviewed on a sample of cases. Incidence was estimated using regression models accounting for age and laboratory testing method; sampling weights were applied to estimate hospitalizations, recurrences, and deaths.Results. A total of 3503 NHO-CDI cases were identified. Among 262 sampled cases, median age was 82 years, 76% received antibiotics in the 12 weeks prior to the C difficile-positive specimen, and 57% were discharged from a hospital in the month before specimen collection. After adjusting for age and testing method, the 2012 national estimate for NHO-CDI incidence was 112 800 cases (95% confidence interval [CI], 93 400–131 800); 31 400 (28%) were hospitalized within 7 days after a positive specimen (95% CI, 25 500–37 300), 20 900 (19%) recurred within 14–60 days (95% CI, 14 600–27 100), and 8700 (8%) died within 30 days (95% CI, 6600–10 700).Conclusions. Nursing home onset CDI is associated with substantial morbidity and mortality. Strategies focused on infection prevention in NHs and appropriate antibiotic use in both NHs and acute care settings may decrease the burden of NHO CDI.

Geographic Distribution of Clostridium difficile Infection Burden by Various Counties in Michigan

Background: Clostridium difficile Infection (CDI) is an URGENT level of threat in United States as published by US Government in a stark report entitled “Antibiotic Resistant Threats in the United States, 2013” Yet there is limited information on geographic distribution of CDI in the community. The present study compared the rates of hospital admissions due to CDI, number of ED visits and number of readmissions within 30 days of hospital discharge for all counties of Michigan, USA. Methods: Using Michigan CMS claims data from 2014, we examined geographic trends in C. difficile discharges and readmissions for all counties in Michigan. We then identified counties with the highest number of discharges and readmissions. In additional analysis, we focused on specific clinic providers to understand the burden of CDI among different clinic locations across Michigan. Results: Counties 4, 5 and 7 accounted for a large number of patients with CDI. Patients in these counties also experienced relatively high numbers of 30 day hospital readmissions and emergency department (ED) visits associated with CDI. Analysis of the same data by providers depicted a very similar trend. These high CDI burden NPI providers were located in a tri-county area of counties 4, 5 and 7 in Michigan. Conclusion: The high CDI burden in concentrated pockets in the community suggests that these county health care providers may be amenable to interventions specifically focused on CDI knowledge, prevention and treatment.

The burden of Clostridium difficile infection in Thais: nationwide survey

Background: Data on the incidence and burden of Clostridium difficile infection (CDI) in Asia is limited. Objectives: To evaluate the incidence and burden of CDI in Thailand. Methods: We used 2010 Nationwide Hospital Admission Data, which included the diagnosis of digestive disorders from various causes coded using the ICD-10. Patients with a diagnosis of Clostridium difficile (ICD10-A07) aged >18 years, were included. Their baseline characteristics, clinical outcomes, and risk factors for CDI were analyzed. Length of hospital stay (LOS), mortality rate, and hospital expenses were used as indicators to evaluate the burden of CDI in Thailand. Results: Of 4,863,935 admissions in 2010, 554 patients in 570 admissions (0.01%) were diagnosed with CDI. Of these, 106 (19.1%) died during the index hospitalization, and 98.1% had at least one comorbidity. The mean LOS for patients with CDI was longer than with other colitis (P who died during the index admission, compared with those who survived during the index admission (P = 0.04). The hospital expense for those who died was significantly higher than for those who survived (P From a multivariate analysis, age ?85 years old, comorbidity, and sepsis were risk factors for mortality during admission with adjusted odds ratios of 2.40, 7.4, and 5.14, respectively. Conclusions: The calculated burden of CDI in Thais is high; although the incidence of CDI is lower in Thailand than in Western countries. The mortality relates to the elderly age-group and comorbidity, especially sepsis. Keywords: Burden, Clostridium difficile infection, nationwide study, Southeast Asia, Thailand, epidemiology

Clostridium difficile Diarrhea in the Elderly: Current Issues and Management Options.

Clostridium difficile infection (CDI) is the most common cause of infectious diarrhea in healthcare settings. Along with antimicrobial exposure, advanced age has been shown to be a significant risk factor for the development and recurrence of, and mortality from, CDI. The substantial burden of CDI in the elderly may be related to frequent healthcare exposure, the necessity for more medications, altered intestinal microbiota, and complicated comorbidities. A diagnosis of CDI is based on evidence of toxin, or the C. difficile organism itself, in a stool sample in the presence of clinical signs and symptoms. Only symptomatic patients should be tested for CDI, and routine surveillance or repeat testing on asymptomatic patients as a test of cure is discouraged. Antibiotic discontinuation alone can improve or resolve CDI in some patients, and concomitant use of antibiotics is associated with decreased response to CDI treatment. Metronidazole, vancomycin, and fidaxomicin are the therapeutic agents currently available for CDI, with the selection of these agents being based on disease severity, history of recurrence, and cost. The recurrence rate after initial treatment is 20-30%. The first recurrence can be treated with the same therapeutic agent and, for subsequent recurrences, vancomycin in a tapered and/or pulsed regimen is recommended. Fecal microbiota transplantation has shown remarkable effectiveness for recurrent anti-refractory CDI, although caution is advised in treating immunocompromised hosts and those with toxic megacolon. C. difficile can be transmitted directly and indirectly via contact with patients or their environment; therefore, isolation precautions should be initiated at the first suspicion of CDI. C. difficile spores can survive for a long time on environmental surfaces, and the patient's room and all equipment used in the room should be disinfected. In order to manage CDI in the elderly, timely diagnosis, appropriate treatment based on severity of illness, and effective infection control are essential.

Hospital cost of Clostridium difficile infection including the contribution of recurrences in French acute-care hospitals

The impact of Clostridium difficile infection (CDI) on healthcare costs is significant due to the extra costs of associated inpatient care. However, the specific contribution of recurrences has rarely been studied. The aim of this study was to estimate the hospital costs of CDI and the fraction attributable to recurrences in French acute-care hospitals. A retrospective study was performed for 2011 on a sample of 12 large acute-care hospitals. CDI costs were estimated from both hospital and public insurance perspectives. For each stay, CDI additional costs were estimated by comparison to controls without CDI extracted from the national DRG (diagnosis-related group) database and matched on DRG, age and sex. When CDI was the primary diagnosis, the full cost of stay was used. A total of 1067 bacteriological cases of CDI were identified corresponding to 979 stays involving 906 different patients. Recurrence(s) were identified in 118 (12%) of these stays with 51.7% of them having occurred within the same stay as the index episode. Their mean length of stay was 63.8 days compared to 25.1 days for stays with an index case only. The mean extra cost per stay with CDI was estimated at €9,575 (median: €7,514). The extra cost of CDI in public acute-care hospitals was extrapolated to €163.1 million at the national level, of which 12.5% was attributable to recurrences. The economic burden of CDI is substantial and directly impacts healthcare systems in France.

Impact of Clostridium difficile infection among pneumonia and urinary tract infection hospitalizations: an analysis of the Nationwide Inpatient Sample.

BackgroundClostridium difficile infection (CDI) remains one of the major hospital acquired infections in the nation, often attributable to increased antibiotic use. Little research, however, exists on the prevalence and impact of CDI on patient and hospital outcomes among populations requiring such treatment. As such, the goal of this study was to examine the prevalence, risk factors, and impact of CDI among pneumonia and urinary tract infection (UTI) hospitalizations.MethodsThe Nationwide Inpatient Sample (2009–2011), reflecting a 20% stratified sample of community hospitals in the United States, was used. A total of 593,038 pneumonia and 255,770 UTI discharges were included. Survey-weighted multivariable regression analyses were conducted to assess the predictors and impact of CDI among pneumonia and UTI discharges.ResultsA significantly higher prevalence of CDI was present among men with UTI (13.3 per 1,000) as compared to women (11.3 per 1,000). CDI was associated with higher in-hospital mortality among discharges for pneumonia (adjusted odds ratio [aOR] for men = 3.2, women aOR = 2.8) and UTI (aOR for men = 4.1, women aOR = 3.4). Length of stay among pneumonia and UTI discharges were also double upon presence of CDI. In addition, CDI increased the total charges by at least 75% and 55% among pneumonia and UTI discharges, respectively. Patient and hospital characteristics associated with CDI included being 65 years or older, Charlson Deyo index for comorbidity of 2 or more, Medicare as the primary payer, and discharge from urban hospitals, among both pneumonia and UTI discharges.ConclusionCDI occurs frequently in hospitalizations among those discharged from hospital for pneumonia and UTI, and is associated with increased in-hospital mortality and health resource utilization. Interventions to mitigate the burden of CDI in these high-risk populations are urgently needed.

Burden of Clostridium difficile infection in the United States.

for the CHIPS Study Group Since publication of their article, the authors report no further potential conflict of interest. 1. Lewis G, ed. Saving mothers’ lives: reviewing maternal deaths to make motherhood safer — 2003-2005: the seventh report on confidential enquiries into maternal deaths in the United Kingdom. London: The Confidential Enquiry into Maternal and Child Health (CEMACH), December 2007 (http://www.hqip.org.uk/ assets/NCAPOP-Library/CMACE-Reports/18.-December-2007 -Saving-Mothers-Lives-reviewing-maternal-deaths-to-make -motherhood-safer-2003-2005-Executive-Summary.pdf).

PTU-333 Clostridium difficile infection rate of recurrence is lower, and mortality is higher, in a large teaching hospital trust than in clinical trials: a prospective observational study

Introduction Clostridium difficile infection (CDI) is the most common nosocomial infection in the United Kingdom. New treatments have shown reduction in CDI recurrence in clinical trials. Their high cost has been justified by savings on treatment of recurrence and reduction in financial penalties. However, in such a sick group of patients with multiple comorbidities recruitment rates to clinical trials are typically very low. A service development project was initiated to assess the current local burden of CDI and rates of recurrence. Method For one year, between 30 th October 2013 and 2014, all samples tested positive for C. difficile toxin production (Techlab Toxin AB Quikcheck) in the Microbiology department of Nottingham University Hospitals NHS Trust (NUH) were identified. Baseline age, leukocyte count, CRP, albumin and creatinine were recorded as well as use of proton pump inhibitors or other antibiotics if treatment was initiated by NUH. The main outcome measure was CDI recurrence within 6 months, with a particular focus on those treated by, and re-presenting to, NUH. At time of submission 6-month data is available for most cases with 3-month data available for all. In April 2014 the Trust adopted the use of Fidaxomicin for recurrent cases of CDI and for those receiving concomitant antibiotic treatment. Results After exclusion of samples sent during the same episode ( nd recurrence, all of whom had been treated with Fidaxomicin on 1 st recurrence. 15 others received Fidaxomicin, 9 of whom had not responded to other treatment or recurred. There was no clear predictor of likelihood of recurrence. 32/121 patients died within 6 months of CDI (26%), of whom 23 died within 3 months (19%). Conclusion CDI recurrence rates in medically treated patients were much lower than that reported for standard therapy in previous clinical trials (25%). Mortality in the medically treated group was much higher than in trials (6–7%) but similar to previous observational studies, reflecting under-representation of very sick patients in clinical trials. Treatment guidelines should recognise this limitation when applying clinical trial results to their patient population. Disclosure of interest V. Wilkinson-Smith: None Declared, L. Koay: None Declared, T. Hills: None Declared, M. Diggle: None Declared, G. Major: None Declared, R. Spiller Grant/ Research Support from: Lesaffre, Ironwood, Norgine, Falk Pharma, Consultant for: Almirall, Astellas, Yuhan, Danone.

The impact of Clostridium difficile infection on resource use and costs in hospitals in Spain and Italy: a matched cohort study

To assess the impact of Clostridium difficile infection (CDI) on hospital resources and costs in Spain and Italy. CDI data were collected from institutions in Spain and Italy. Each patient was matched with two randomly selected uninfected controls in the same institution. Patient outcomes were assessed for the first and second episodes of CDI and for patients aged ≤65 and >65 years. The impact of CDI on hospital length of stay (LOS) was used to calculate CDI-attributable costs. A multivariate analysis using duration of stay as the continuous outcome variable assessed the independent effect of CDI on hospital costs and LOS. LOS attributable to CDI ranged from 7.6-19.0 days in adults and was 5.0 days in children; the increases were greater in adults in Italy than in Spain. Attributable costs per adult patient ranged from €4396 in Madrid to €14023 in Rome, with the majority of the cost being due to hospitalization. For children, the total attributable cost was €3545/patient. These data show that the burden of CDI is considerable in Spain and Italy. Treatments that can reduce LOS, disease severity, and recurrence rates, as well as effective infection control measures to prevent transmission, have the potential to reduce the burden of CDI.

Tu1091 The Burden of Clostridium difficile Infection in Thai Population: The First Report in Thailand by 2010 Nationwide Study

Tu1091 The Burden of Clostridium difficile Infection in Thai Population: The First Report in Thailand by 2010 Nationwide Study

The economic impact of Clostridium difficile infection: a systematic review.

With Clostridium difficile infection (CDI) on the rise, knowledge of the current economic burden of CDI can inform decisions on interventions related to CDI. We systematically reviewed CDI cost-of-illness (COI) studies. We performed literature searches in six databases: MEDLINE, Embase, the Health Technology Assessment Database, the National Health Service Economic Evaluation Database, the Cost-Effectiveness Analysis Registry, and EconLit. We also searched gray literature and conducted reference list searches. Two reviewers screened articles independently. One reviewer abstracted data and assessed quality using a modified guideline for economic evaluations. The second reviewer validated the abstraction and assessment. We identified 45 COI studies between 1988 and June 2014. Most (84%) of the studies were from the United States, calculating costs of hospital stays (87%), and focusing on direct costs (100%). Attributable mean CDI costs ranged from $8,911 to $30,049 for hospitalized patients. Few studies stated resource quantification methods (0%), an epidemiological approach (0%), or a justified study perspective (16%) in their cost analyses. In addition, few studies conducted sensitivity analyses (7%). Forty-five COI studies quantified and confirmed the economic impact of CDI. Costing methods across studies were heterogeneous. Future studies should follow standard COI methodology, expand study perspectives (e.g., patient), and explore populations least studied (e.g., community-acquired CDI).