Incidence and outcomes of Clostridium difficile-associated disease in hematopoietic cell transplant recipients

Clostridioides difficile infection: history, epidemiology, risk factors, prevention, clinical manifestations, treatment, and future options

SUMMARYClostridioides difficile infection (CDI) is one of the major issues in nosocomial infections. This bacterium is constantly evolving and poses complex challenges for clinicians, often encountered in real-life scenarios. In the face of CDI, we are increasingly equipped with new therapeutic strategies, such as monoclonal antibodies and live biotherapeutic products, which need to be thoroughly understood to fully harness their benefits. Moreover, interesting options are currently under study for the future, including bacteriophages, vaccines, and antibiotic inhibitors. Surveillance and prevention strategies continue to play a pivotal role in limiting the spread of the infection. In this review, we aim to provide the reader with a comprehensive overview of epidemiological aspects, predisposing factors, clinical manifestations, diagnostic tools, and current and future prophylactic and therapeutic options for C. difficile infection.

Diarrheal woes in transplantation from real world settings with special focus on clostridium difficile infection

Background

Diarrhea is the major cause of discomfort and morbidity of patients undergoing hematopoietic stem cell transplant (HSCT). The cause of diarrhea may be infective or non-infective.

Methods

This is a prospective single center observational study from North India conducted over a period of approximately 4 years among 105 patients who underwent HSCT (autologous-72, allogeneic-33). The objective of the study was to identify the overall incidence and characteristics of diarrhea in HSCT in the real world, to evaluate any differences among allogeneic or autologous transplants, incidence of C Difficile among diarrheal patients, and antimicrobial usage among these patients.

Results

Diarrhea was present in 89 of 105 patients (84.7%). The mean diarrheal duration was of 8.39±4.57 days (range: 1-24 days). There was non statistical difference between the incidence of diarrhea amongst allogeneic and autologous transplants (78.9% Vs 87.5%). Out of 89 patients with diarrhea, 13 were CDTA positive. We could isolate Clostridium difficile in culture in only 7.6% of patients with CDTA positivity. Metronidazole was the antibiotic of choice for diarrhea in our post-transplant settings. Metronidazole was prescribed for a median duration of 8 days (Range: 3-18 days). Seventeen patients received oral vancomycin with a median duration of 8 days (Range: 5-14 days).

Conclusion

We conclude by saying that diarrhea was a common post-transplant morbidity. Clostridium difficile is not common in patients with the diarrhea post hematopoietic stem cell transplant. All cases of diarrhea need not be infective particularly in allogeneic settings.

How I approach diarrhea in hematological transplant patients: A practical tool

Diarrhea in hematopoietic stem-cell transplantation (HSCT) remains a multifactorial challenge that demands a nuanced diagnostic approach. The causes of infectious diarrhea in HSCT recipients are diverse and influenced by patient-specific risk factors, the post-transplant timeline, and local epidemiology. During the past decade, our understanding of diarrhea in HSCT has witnessed a transformative shift through the incorporation of gastrointestinal (GI) multiplex polymerase chain reaction (PCR) panels. However, the judicious application of these panels is imperative to avoid overtesting and prevent adverse outcomes. The challenge lies in distinguishing between the diverse causes of diarrhea, ascertaining the clinical significance of detected pathogens, and navigating the diagnostic uncertainty presented by several non-infectious conditions such as mucositis, intestinal dysbiosis, and acute graft-versus-host disease (aGvHD), all of which mimic infection. This review examines the landscape of infectious diarrhea in the HSCT population, encompassing both established (e.g., Cytomegalovirus, Clostridioides difficile, and norovirus) and emerging pathogens (e.g., sapoviruses, astroviruses). We propose a multifaceted diagnostic algorithm that combines clinical assessment, risk stratification, and tailored utilization of molecular platforms. While multiplex GI panels present invaluable opportunities for rapid and comprehensive pathogen detection, their judicious use is pivotal in preserving diagnostic stewardship. Customization of diagnostic algorithms tailored to local epidemiology ensures optimal patient care and resource utilization.

Minimizing the risk of Clostridioides difficile infection as an early complication of autologous stem cell transplantation

This quality improvement project aimed to reduce institutional incidence of Clostridioides difficile infection (CDI) following autologous stem cell transplantation. CDI incidence per transplant was .17 in a baseline period and .09 following the implementation of postdischarge ultraviolet room cleaning (χ2 = 2.11, p = .15).

Predicted Bezlotoxumab Exposure in Patients Who Have Received a Hematopoietic Stem Cell Transplant

PURPOSE

Bezlotoxumab is approved for prevention of recurrent Clostridioides (Clostridium) difficile infection (CDI) in adults receiving antibacterial treatment for CDI who are at high risk for recurrent CDI. Previous studies have shown that although serum albumin levels are an important predictor for bezlotoxumab exposure, this has no clinically meaningful impact on efficacy. This pharmacokinetic modeling study assessed whether hematopoietic stem cell transplant (HSCT) recipients, at increased risk of CDI and exhibiting decreased albumin levels within the first month posttransplant, are at risk of clinically relevant reductions in bezlotoxumab exposure.

METHODS

Observed bezlotoxumab concentration-time data pooled from participants in Phase III trials MODIFY I and II (ClinicalTrials.gov identifiers NCT01241552/NCT01513239) and three Phase I studies (PN004, PN005, and PN006) were used to predict bezlotoxumab exposures in two adult post-HSCT populations: A Phase Ib study of posaconazole including allogeneic HSCT recipients (ClinicalTrials.gov identifier NCT01777763; posaconazole-HSCT population); and a Phase III study of fidaxomicin for CDI prophylaxis (ClinicalTrials.gov identifier NCT01691248; fidaxomicin-HSCT population). The bezlotoxumab PK model used the minimum albumin level for each individual in post-HSCT populations to mimic a "worst-case scenario."

FINDINGS

Predicted worst-case bezlotoxumab exposures for the posaconazole-HSCT population (N = 87) were decreased by 10.8% versus bezlotoxumab exposures observed in the pooled Phase III/Phase I data set (N = 1587). No further decrease was predicted for the fidaxomicin-HSCT population (N = 350).

IMPLICATIONS

Based on published population pharmacokinetic data, the predicted decrease in bezlotoxumab exposure in the post-HSCT populations is not expected to have a clinically meaningful effect on bezlotoxumab efficacy at the recommended 10 mg/kg dose. Dose modification is therefore not required in the hypoalbuminemia setting expected post-HSCT. (Clin Ther. 2023;45:XXX-XXX) © 2023 Elsevier HS Journals, Inc.

Risk Factors and Outcome of C. difficile Infection after Hematopoietic Stem Cell Transplantation

Patients who undergo hematopoietic stem cell transplants (HSCT) are at major risk of C. difficile (CD) infection (CDI), the most common cause of nosocomial diarrhea. We conducted a retrospective study, which enrolled 481 patients who underwent autologous (220) or allogeneic HSCT (261) in a 5-year period, with the aim of identifying the incidence, risk factors and outcome of CDI between the start of conditioning and 100 days after HSCT. The overall cumulative incidence of CDI based upon clinical evidence was 5.4% (95% CI, 3.7% to 7.8%), without any significant difference between the two types of procedures. The median time between HSCT and CDI diagnosis was 12 days. Out of 26 patients, 19 (73%) with clinical and symptomatic evidence of CDI were positive also for enzymatic or molecular detection of toxigenic CD; in particular, in 5 out of 26 patients (19%) CD binary toxin was also detected. CDI diagnoses significantly increased in the period 2018-2019, since the introduction in the microbiology lab unit of the two-step diagnostic test based on GDH immunoenzymatic detection and toxin B/binary toxin/027 ribotype detection by real-time PCR. Via multivariate analysis, abdominal surgery within 10 years before HSCT (p = 0.002), antibiotic therapy within two months before HSCT (p = 0.000), HCV infection (p = 0.023) and occurrence of bacterial or fungal infections up to 100 days after HSCT (p = 0.003) were significantly associated with a higher risk of CDI development. The 26 patients were treated with first-line vancomycin (24) or fidaxomicine (2) and only 2 patients needed a second-line treatment, due to the persistence of stool positivity. No significant relationship was identified between CDI and the development of acute graft versus host disease (GVHD) after allogeneic HSCT. At a median follow-up of 25 months (range 1-65), the cumulative incidence of transplant related mortality (TRM) was 16.6% (95% CI 11.7% to 22.4%) and the 3-year overall survival (OS) was 67.0% (95% CI 61.9% to 71.6%). The development of CDI had no significant impact on TRM and OS, which were significantly impaired in the multivariate analysis by gastrointestinal and urogenital comorbidities, severe GVHD, previous infections or hospitalization within two months before HSCT, active disease at transplant and occurrence of infections after HSCT. We conclude that 20% of all episodes of diarrhea occurring up to 100 days after HSCT were related to toxigenic CD infection. Patients with a history of previous abdominal surgery or HCV infection, or those who had received broad spectrum parenteral antibacterial therapy were at major risk for CDI development. CDIs were successfully treated with vancomycin or fidaxomicin after auto-HSCT as well as after allo-HSCT.

Impact of Clostridioides difficile infection on the outcome of patients receiving a hematopoietic stem cell transplantation

OBJECTIVES

Clostridioides difficile infections (CDI) are common in autologous (auto-HSCT) or allogenic hematopoietic stem cell transplant (allo-HSCT) recipients. However, the impact of CDI on patient outcomes is controversial. We conducted this study to examine the impact of CDI on patient outcomes.

METHODS

We performed a retrospective single-center study, including 191 lymphoma patients receiving an auto-HSCT and 276 acute myeloid leukemia (AML) patients receiving an allo-HSCT. The primary endpoint was overall survival (OS). Secondary endpoints were causes of death and, for the allo-HSCT cohort, GvHD- and relapse-free survival (GRFS).

RESULTS

The prevalence of CDI was 17.6% in the AML allo-HSCT and 7.3% in the lymphoma auto-HSCT cohort. A higher prevalence of bloodstream infections, but no differences concerning OS or cause of death were found for patients with CDI in the auto-HSCT cohort. [AU] In the allo-HSCT cohort, OS and GRFS were similar between CDI and non-CDI patients. However, the leading cause of death was relapse among non-CDI patients, but it was infectious diseases in the CDI group with fewer deaths due to relapse.

CONCLUSIONS

CDI was not associated with worse survival in patients receiving a hematopoietic stem cell transplantation, and there were even fewer relapse-related deaths in the AML allo-HSCT cohort.

Incidence and Outcomes Associated With Clostridium difficile Infections: A Systematic Review and Meta-analysis

IMPORTANCE

An understanding of the incidence and outcomes of Clostridium difficile infection (CDI) in the United States can inform investments in prevention and treatment interventions.

OBJECTIVE

To quantify the incidence of CDI and its associated hospital length of stay (LOS) in the United States using a systematic literature review and meta-analysis.

DATA SOURCES

MEDLINE via Ovid, Cochrane Library Databases via Wiley, Cumulative Index of Nursing and Allied Health Complete via EBSCO Information Services, Scopus, and Web of Science were searched for studies published in the United States between 2000 and 2019 that evaluated CDI and its associated LOS.

STUDY SELECTION

Incidence data were collected only from multicenter studies that had at least 5 sites. The LOS studies were included only if they assessed postinfection LOS or used methods accounting for time to infection using a multistate model or compared propensity score-matched patients with CDI with control patients without CDI. Long-term-care facility studies were excluded. Of the 119 full-text articles, 86 studies (72.3%) met the selection criteria.

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers performed the data abstraction and quality assessment. Incidence data were pooled only when the denominators used the same units (eg, patient-days). These data were pooled by summing the number of hospital-onset CDI incident cases and the denominators across studies. Random-effects models were used to obtain pooled mean differences. Heterogeneity was assessed using the I2 value. Data analysis was performed in February 2019.

MAIN OUTCOMES AND MEASURES

Incidence of CDI and CDI-associated hospital LOS in the United States.

RESULTS

When the 13 studies that evaluated incidence data in patient-days due to hospital-onset CDI were pooled, the CDI incidence rate was 8.3 cases per 10 000 patient-days. Among propensity score-matched studies (16 of 20 studies), the CDI-associated mean difference in LOS (in days) between patients with and without CDI varied from 3.0 days (95% CI, 1.44-4.63 days) to 21.6 days (95% CI, 19.29-23.90 days).

CONCLUSIONS AND RELEVANCE

Pooled estimates from currently available literature suggest that CDI is associated with a large burden on the health care system. However, these estimates should be interpreted with caution because higher-quality studies should be completed to guide future evaluations of CDI prevention and treatment interventions.

Clostridium Difficile infections in patients with AML or MDS undergoing allogeneic hematopoietic stem cell transplantation identify high risk for adverse outcome

Clostridium difficile (CD) infection is the main cause of nosocomial enterocolitis in western countries and in patients undergoing allogeneic hematopoietic stem cell transplantation (alloHCT). Recipients of alloHCT are at high risk for CD infection but large studies in this population are rare and conflicting results have been reported. We analyzed 727 patients with AML or MDS undergoing alloHCT in our center from 2004 to 2015. Ninety-six patients (13%) had CD infection and 103 patients (14%) were identified as asymptomatic carriers by screening at admission and once a week during aplasia. Patients with CD infection had a shorter median overall survival of 8 months (95% CI, 6-36 months) compared with 25 months (95% CI, 17-35 months) for patients without CD infection, (HR 1.4, p = 0.04). CD positive patients were less likely to develop acute graft-versus-host disease (aGvHD; HR 0.6, p = 0.004) compared with CD-negative patients, but did not show differences in gastrointestinal aGvHD (HR 0.9, p = 0.5). Symptomatic patients developed gastrointestinal aGvHD (HR 2.5, p = 0.02) more often compared with asymptomatic CD positive patients. This analysis demonstrates a high prevalence for CD infection in patients undergoing alloHCT. A significant lower overall survival for patients with CD infection could be demonstrated.

In-hospital mortality of hematopoietic stem cell transplantation among children with nonmalignancies: A nationwide study in the United States from 2000 to 2012

BACKGROUND

Hematopoietic stem cell transplant (HSCT) can cure or alleviate a wide range of nonmalignant childhood conditions. However, few studies have examined longitudinal national trends of frequency or short-term complications of HSCT before 2006 when an HSCT became a reportable procedure by US law. By using a US nationally representative database, we conducted nationwide longitudinal analyses on demographics, in-hospital mortality, and short-term complications in nonmalignant HSCT from 2000 to 2012.

PROCEDURE

We analyzed 2504 admissions for children < 20 years old who underwent an allogeneic HSCT for a nonmalignant condition by using the Kids' Inpatient Database for the years 2000, 2003, 2006, 2009, and 2012. Changes in in-hospital mortality and other outcomes were assessed over the study period using weighted analyses, which enabled generation of national estimates in each year.

RESULTS

The number of admissions for HSCT increased from 334 to 667 from 2000 to 2012, respectively; among them, the use of bone marrow decreased (66.5% to 34.1%, P < 0.001). In-hospital mortality declined (13.4% to 7.1%, P = 0.04), as did bacteremia (28.7% to 10.1%, P < 0.001) and vascular catheter infections (18.8% to 8.7%, P = 0.006), but cytomegalovirus infections increased (4.9% to 15.9%, P < 0.001), as did adenovirus infections (1.8% to 6.9%, P < 0.001) from 2000 to 2012.

CONCLUSION

Population-based analyses demonstrated a substantial expansion of the utilization of HSCT occurred for pediatric nonmalignancies from 2000 to 2012 in the United States, whereas the in-hospital mortality declined by approximately a half. Further research is needed to identify distinct contributing factors.

Clostridioides difficile Infection in the Stem Cell Transplant and Hematologic Malignancy Population

Clostridioides difficile infection (CDI) is common in the stem cell transplant (SCT) and hematologic malignancy (HM) population and mostly occurs in the early posttransplant period. Treatment of CDI in SCT/HM is the same as for the general population, with the exception that fecal microbiota transplant (FMT) has not been widely adopted because of safety concerns. Several case reports, small series, and retrospective studies have shown that FMT is effective and safe. A randomized controlled trial of FMT for prophylaxis of CDI in SCT patients is underway. In addition, an abundance of novel therapeutics for CDI is currently in development.

Oral Vancomycin Prophylaxis Is Highly Effective in Preventing Clostridium difficile Infection in Allogeneic Hematopoietic Cell Transplant Recipients

BACKGROUND

Clostridium difficile infection (CDI) is a leading cause of infectious complications in allogeneic hematopoietic cell transplant recipients (alloHCT). We sought to evaluate whether prophylactic oral vancomycin reduces the incidence of CDI in alloHCT recipients.

METHODS

We conducted a retrospective cohort study to examine the effectiveness of CDI prophylaxis with oral vancomycin, as compared to no prophylaxis, in 145 consecutive adult alloHCT recipients at the University of Pennsylvania between April 2015 and November 2016. Patients received oral vancomycin 125 mg twice daily, starting on admission and continuing until discharge. The primary outcome of interest was the association between oral vancomycin prophylaxis and CDI diagnosis. Secondary outcomes included graft-versus-host disease (GVHD) and relapse.

RESULTS

There were no cases of CDI in patients that received prophylaxis (0/90, 0%), whereas 11/55 (20%) patients who did not receive prophylaxis developed CDI (P < .001). Oral vancomycin prophylaxis was not associated with a higher risk of acute, grades 2-4 GVHD (subhazard ratio [sHR] 1.59; 95% confidence interval [CI] 0.88-2.89; P = .12), acute, grades 3-4 GVHD (sHR 0.65; 95% CI 0.25-1.66; P = .36), or acute, grades 2-4 gastrointestinal GVHD (sHR 1.95; 95% CI 0.93-4.07; P = .08) at day 180 post-transplant. No associations between oral vancomycin and relapse or survival were observed.

CONCLUSIONS

Prophylaxis with oral vancomycin is highly effective in preventing CDI in alloHCT recipients without increasing the risk of graft-versus-host disease or disease relapse. Further evaluation via a prospective study is warranted.

Risk, Outcomes, and Predictors of Clostridium difficile Infection in Lymphoma: A Nationwide Study

OBJECTIVE

The risk of Clostridium difficile infection (CDI) has not been well studied in patients with lymphoma. We thus sought to determine the risk of CDI in hospitalizations with lymphoma along with its trend, outcomes, and predictors using a large database.

METHODS

Hospital discharge data from the Nationwide Inpatient Sample (NIS) from 2007 to 2011 were used for the study. Using the International Classification of Diseases, Ninth Revision, Clinical Modification codes, all adult patients aged 18 years or older having a primary diagnosis of lymphoma were queried for the presence of CDI as any of the secondary diagnoses. The risk of CDI in lymphoma and its yearly trend were assessed. We performed multivariate logistic regression to determine the independent risk factors of CDI in lymphoma. Furthermore, we studied mortality and other adverse outcomes of CDI in patients with lymphoma.

RESULTS

There were 236,312 discharges (weighted) with the primary diagnosis of lymphoma. CDI was present in 2.13% of patients with lymphoma versus 0.8% in the nonlymphoma group (P < 0.001). On multivariate analysis, the significant predictors of CDI in lymphoma were presence of infection (odds ratio [OR] 3.1, 95% confidence interval [CI] 2.7-3.6), stem cell transplant (OR 2.7, 95% CI 2.3-3.4), graft-versus-host disease (OR 1.9, 95% CI 1.4-2.8), race (Asian vs white, OR 1.6, 95% CI 1.1-2.4), chemotherapy (OR 1.6, 95% CI 1.4-1.8), gastrointestinal surgery (OR 1.4, 95% CI 1.2-1.7), and Charlson Comorbidity Index (CCI) (CCI of 2 vs 0-1: OR 1.2, 95% CI 1.1-1.4; CCI of 3 vs 0-1: OR 1.3, 95% CI 1.03-1.6). CDI in lymphoma was associated with worse hospital outcomes such as increased mortality (17% vs 8%), increased length of stay (23.6 vs 9.9 days), mean total hospital charges ($197,015 vs $79,392), rate of intubation (13% vs 4% vs 13%), and rate of total parenteral nutrition (11% vs 3%).

CONCLUSIONS

Hospitalization with lymphoma was associated with an increased risk of CDI. The significant predictors for CDI in lymphoma were infection, stem cell transplant, graft-versus-host disease, race, chemotherapy, gastrointestinal surgery, and Charlson Comorbidity Index. CDI in lymphoma was associated with increased mortality and other adverse outcomes warranting a need of more vigilance for CDI in patients with lymphoma.

Emergency general surgery procedures in hematopoietic stem cell transplant recipients

BACKGROUND

Outcomes of emergency general surgery (EGS) procedures on hematopoietic stem cell transplant (HST) recipients have not been defined in a large, national database. Whether EGS during HST engraftment admission, or in HST patients with graft versus host disease (GVHD) results in worse outcomes is unknown.

METHODS

The National Inpatient Sample (NIS) was examined for patients with a history of BMT between 2001 and 2014.

RESULTS

There were 520,000 HST admissions meeting inclusion criteria, of which, 14,143 (2.7%) required EGS. Of those requiring EGS, 378 (2.7%) were during engraftment admission and 13,765 (97.3%) on subsequent admission. For those requiring EGS during subsequent admission, 9,920 (72.1%) had a history of GVHD and 3,845 (27.9%) did not. On multivariate analysis, requirement of EGS was associated with mortality (OR: 1.71, 95%CI: 1.47-1.99, p < 0.001). For patients requiring EGS, engraftment admission or GVHD was not associated with mortality.

CONCLUSIONS

While EGS results in worse survival for the HST population, patients in their engraftment admission do not appear to be at increased mortality risk. In addition, GVHD does not worsen survival.

Incidence Rates and Risk Factors of Clostridioides difficile Infection in Solid Organ and Hematopoietic Stem Cell Transplant Recipients

Background

Transplant recipients are an immunologically vulnerable patient group and are at elevated risk of Clostridioides difficile infection (CDI) compared with other hospitalized populations. However, risk factors for CDI post-transplant are not fully understood.

Methods

Adults undergoing solid organ (SOT) and hematopoietic stem cell transplant (HSCT) from January 2010 to February 2017 at Rigshospitalet, University of Copenhagen, Denmark, were retrospectively included. Using nationwide data capture of all CDI cases, the incidence and risk factors of CDI were assessed.

Results

A total of 1687 patients underwent SOT or HSCT (1114 and 573, respectively), with a median follow-up time (interquartile range) of 1.95 (0.52–4.11) years. CDI was diagnosed in 15% (164) and 20% (114) of the SOT and HSCT recipients, respectively. CDI rates were highest in the 30 days post-transplant for both SOT and HSCT (adjusted incidence rate ratio [aIRR], 6.64; 95% confidence interval [CI], 4.37–10.10; and aIRR, 2.85; 95% CI, 1.83–4.43, respectively, compared with 31–180 days). For SOT recipients, pretransplant CDI and liver and lung transplant were associated with a higher risk of CDI in the first 30 days post-transplant, whereas age and liver transplant were risk factors in the later period. Among HSCT recipients, myeloablative conditioning and a higher Charlson Comorbidity Index were associated with a higher risk of CDI in the early period but not in the late period.

Conclusions

Using nationwide data, we show a high incidence of CDI among transplant recipients. Importantly, we also find that risk factors can vary relative to time post-transplant.

A Randomized, Placebo-controlled Trial of Fidaxomicin for Prophylaxis of Clostridium difficile-associated Diarrhea in Adults Undergoing Hematopoietic Stem Cell Transplantation

Background

Clostridium difficile-associated diarrhea (CDAD) is common during hematopoietic stem-cell transplantation (HSCT) and is associated with increased morbidity and mortality. We evaluated fidaxomicin for prevention of CDAD in HSCT patients.

Methods

In this double-blind study, subjects undergoing HSCT with fluoroquinolone prophylaxis stratified by transplant type (autologous/allogeneic) were randomized to once-daily oral fidaxomicin (200 mg) or a matching placebo. Dosing began within 2 days of starting conditioning or fluoroquinolone prophylaxis and continued until 7 days after neutrophil engraftment or completion of fluoroquinolone prophylaxis/clinically-indicated antimicrobials for up to 40 days. The primary endpoint was CDAD incidence through 30 days after study medication. The primary endpoint analysis counted confirmed CDAD, receipt of CDAD-effective medications (for any indication), and missing CDAD assessment (for any reason, including death) as failures; this composite analysis is referred to as "prophylaxis failure" to distinguish from the pre-specified sensitivity analysis, which counted only confirmed CDAD (by toxin immunoassay or nucleic acid amplification test) as failure.

Results

Of 611 subjects enrolled, 600 were treated and analyzed. Prophylaxis failure was similar in fidaxomicin and placebo recipients (28.6% vs 30.8%; difference 2.2% [-5.1, 9.5], P = .278). However, most failures were due to non-CDAD events. Confirmed CDAD was lower in fidaxomicin vs placebo recipients (4.3% vs 10.7%; difference 6.4% [2.2, 10.6], P = .0014). Drug-related adverse events occurred in 15.0% of fidaxomicin recipients and 20.0% of placebo recipients.

Conclusions

While no difference was demonstrated between arms in the primary analysis, results of the sensitivity analysis demonstrated that fidaxomicin significantly reduced the incidence of CDAD in HSCT recipients.

Clinical Trials Registration

NCT01691248.

Retrospective evaluation of fidaxomicin versus oral vancomycin for treatment of Clostridium difficile infections in allogeneic stem cell transplant

OBJECTIVE/BACKGROUND

Clostridium difficile infection (CDI) is a potential complication during hematopoietic stem cell transplantation (HSCT), and no specific recommendations exist regarding treatment of CDI in allogeneic SCT patients. Use of metronidazole and oral vancomycin has been associated with clinical failure. Fidaxomicin has previously been found noninferior to the use of oral vancomycin for the treatment of CDI, and no studies have compared the use of oral vancomycin with fidaxomicin for the treatment of CDI in allogeneic SCT.

METHODS

This retrospective chart review included 96 allogeneic SCT recipients who developed CDI within 100 days following transplantation. Participants were treated with oral vancomycin (n = 52) or fidaxomicin (n = 44). The primary outcome was clinical cure, defined as no need for further retreatment 2 days following completion of initial CDI treatment. Secondary outcomes were global cure, treatment failure, and recurrent disease.

RESULTS

No differences in clinical cure were observed between patients receiving oral vancomycin or fidaxomicin (75% vs. 75%, p = 1.00). Secondary outcomes were similar between oral vancomycin and fidaxomicin in regards to global cure (66% vs. 67%, p = .508), treatment failure (28% vs. 27%, p = .571), and recurrent disease (7% vs. 5%, p = .747). In a subanalysis of individuals that developed acute graft-versus-host disease following CDI, the difference in mean onset of acute graft-versus-host disease was 21.03 days in the oral vancomycin group versus 32.88 days in the fidaxomicin group (p = .0031).

CONCLUSION

The findings of this study suggest that oral vancomycin and fidaxomicin are comparable options for CDI treatment in allogeneic SCT patients within 100 days following transplant.

Treating Clostridium difficile infection in patients presenting with hematological malignancies: Are current guidelines applicable?

OBJECTIVES

Adults with hematological malignancies are at high-risk of Clostridium difficile infection (CDI), but no guidelines for CDI treatment are available in this population. Our primary objective was to evaluate the clinical outcomes in CDI patients with hematological malignancies. Our secondary objectives were to describe CDI severity using the main clinical guidelines and to evaluate the compliance of treatment choice with published guidelines.

PATIENTS AND METHODS

Single-center, retrospective, observational case series including every consecutive adult patient with a confirmed diagnosis of CDI admitted in the hematology unit of our teaching hospital. Each CDI episode was classified as moderate, severe, or complicated according to the main clinical guidelines (IDSA 2010, AJG 2013, ESCMID 2014).

RESULTS

Twenty-three episodes of CDI in 19 patients admitted to the hematology unit occurred between June 2012 and October 2013. Clinical cure was achieved for 20 episodes (87%). Ten weeks after diagnosis, global cure was reached for 14 episodes (61%) whereas recurrence occurred in two episodes (10%). The mortality rate reached 37% (7/19) but the attributable mortality rate was 5% (1/19). ESCMID criteria more frequently classified patients in the severe category compared with the two other classifications. Prescription compliance with clinical guidelines was observed in 61% of episodes with IDSA criteria, 43% with AJG, and 9% with ESCMID.

CONCLUSIONS

IDSA and AJG assessment may underestimate the potential risk of unfavorable clinical outcome. Further prospective studies on a larger cohort are needed to develop adequate treatment guidelines for CDI in hematology settings.

Infections in Hematopoietic Cell Transplant Recipients: Results From the Organ Transplant Infection Project, a Multicenter, Prospective, Cohort Study

Background

Infection is a major cause of morbidity and mortality after allogeneic hematopoietic cell transplantation (HCT). Our object was to better define the epidemiology and outcomes of infections after HCT.

Methods

This was a prospective, multicenter cohort study of HCT recipients and conducted from 2006 to 2011.

The study included 4 US transplant centers and 444 HCT recipients. Data were prospectively collected for up to 30 months after HCT using a standardized data collection tool.

Results

The median age was 53 years, and median follow up was 413 (range, 5–980) days. The most common reason for HCT was hematologic malignancy (87%). The overall crude mortality was 52%. Death was due to underlying disease in 44% cases and infection in 21%. Bacteremia occurred in 231 (52%) cases and occurred early posttransplant (median day 48). Gram-negative bloodstream infections were less frequent than Gram-positive, but it was associated with higher mortality (45% vs 13%, P = .02). Clostridium difficile infection developed in 148 patients (33%) at a median of 27 days post-HCT. There were 53 invasive fungal infections (IFIs) among 48 patients (11%). The median time to IFI was 142 days. Of 155 patients with cytomegalovirus (CMV) infection, 4% had CMV organ involvement. Varicella zoster infection (VZV) occurred in 13 (4%) cases and was disseminated in 2. Infection with respiratory viruses was seen in 49 patients. Pneumocystis jirovecii pneumonia was rare (1%), and there were no documented cases of nocardiosis, toxoplasmosis, endemic mycoses, or mycobacterial infection. This study lacked standardized antifungal and antiviral prophylactic strategies.

Conclusions

Infection remains a significant cause of morbidity and mortality after HCT. Bacteremias and C difficile infection are frequent, particularly in the early posttransplant period. The rate of IFI is approximately 10%. Organ involvement with CMV is infrequent, as are serious infections with VZV and herpes simplex virus, likely reflecting improved prevention strategies.

Clostridium difficile

Clostridium difficile infections (CDIs) have emerged as one of the principal threats to the health of hospitalized and immunocompromised patients. The importance of C difficile colonization is increasingly recognized not only as a source for false-positive clinical testing but also as a source of new infections within hospitals and other health care environments. In the last five years, several new treatment strategies that capitalize on the increasing understanding of the altered microbiome and host defenses in patients with CDI have completed clinical trials, including fecal microbiota transplantation. This article highlights the changing epidemiology, laboratory diagnostics, pathogenesis, and treatment of CDI.

Risk factors for the development of Clostridium difficile infection in adult allogeneic hematopoietic stem cell transplant recipients: A single-center study in Québec, Canada

BACKGROUND

Clostridium difficile infection (CDI) is a significant complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT). Our primary objective was to determine risk factors for the development of CDI during the first year following allo-HSCT.

METHODS

A matched case-control study nested in a cohort of allo-HSCT at a single hospital in Montréal, Québec, Canada, was conducted from 2002 through 2011.

RESULTS

Sixty-five of 760 patients who underwent allo-HSCT between 2002 and 2011 developed CDI, representing an incidence of 8.6%. We selected 123 controls matched for year of transplant for risk factor analyses. In the multivariable analysis, receipt of trimethoprim-sulfamethoxazole (TMP-SMX) prior to transplantation (adjusted odds ratio [aOR] 0.07, 95% confidence interval [CI] 0.02-0.27), mucositis (aOR 5.90, 95% CI 2.08-16.72), and reactivation of cytomegalovirus (CMV) (aOR 6.17, 95% CI 2.17-17.57) and of other Herpesviridae viruses (aOR 3.04, 95% CI 1.13-8.16) were the variables that remained statistically associated with CDI. High-risk antibiotic use in the late post-transplant period (aOR 7.63, 95% CI 2.14-27.22) was associated with development of late CDI.

CONCLUSION

This study revealed reactivation of CMV and other Herpesviridae viruses as novel risk factors for CDI. Administration of TMP-SMX prior to transplantation was independently associated with a decreased risk of CDI. Early and late CDI after HSCT may have distinct risk factors.

Clostridium difficile Infections amongst Patients with Haematological Malignancies: A Data Linkage Study

Objectives

Identify risk factors for Clostridium difficile infection (CDI) and assess CDI outcomes among Australian patients with a haematological malignancy.

Methods

A retrospective cohort study involving all patients admitted to hospitals in Western Australia with a haematological malignancy from July 2011 to June 2012. Hospital admission data were linked with all hospital investigated CDI case data. Potential risk factors were assessed by logistic regression. The risk of death within 60 and 90 days of CDI was assessed by Cox Proportional Hazards regression.

Results

There were 2085 patients of whom 65 had at least one CDI. Twenty percent of CDI cases were either community-acquired, indeterminate source or had only single-day admissions in the 28 days prior to CDI. Using logistic regression, having acute lymphocytic leukaemia, neutropenia and having had bacterial pneumonia or another bacterial infection were associated with CDI. CDI was associated with an increased risk of death within 60 and 90 days post CDI, but only two deaths had CDI recorded as an antecedent factor. Ribotyping information was available for 33 of the 65 CDIs. There were 19 different ribotypes identified.

Conclusions

Neutropenia was strongly associated with CDI. While having CDI is a risk factor for death, in many cases it may not be a direct contributor to death but may reflect patients having higher morbidity. A wide variety of C. difficile ribotypes were found and community-acquired infection may be under-estimated in these patients.

The safety and feasibility of probiotics in children and adolescents undergoing hematopoietic cell transplantation

Hematopoietic cell transplantation (HCT) has become a standard treatment for many adult and pediatric conditions. Emerging evidence suggests that perturbations in the microbiota diversity increase recipients' susceptibilities to gut-mediated conditions such as diarrhea, infection and acute GvHD. Probiotics preserve the microbiota and may minimize the risk of developing a gut-mediated condition; however, their safety has not been evaluated in the setting of HCT. We evaluated the safety and feasibility of the probiotic, Lactobacillus plantarum (LBP), in children and adolescents undergoing allogeneic HCT. Participants received once-daily supplementation with LBP beginning on day -8 or -7 and continued until day +14. Outcomes were compliance with daily administration and incidence of LBP bacteremia. Administration of LBP was feasible with 97% (30/31, 95% confidence interval (CI) 83-100%) of children receiving at least 50% of the probiotic dose (median 97%; range 50-100%). We did not observe any case of LBP bacteremia (0% (0/30) with 95% CI 0-12%). There were not any unexpected adverse events related to LBP. Our study provides preliminary evidence that administration of LBP is safe and feasible in children and adolescents undergoing HCT. Future steps include the conduct of an approved randomized, controlled trial through Children's Oncology Group.

Contribution of Clostridium difficile infection to the development of lower gastrointestinal adverse events during autologous stem cell transplantation

BACKGROUND

Lower gastrointestinal (GI) adverse events (LGAE) are common afflictions of patients undergoing stem cell transplantation (SCT). Unfortunately, the pathophysiology remains poorly characterized. Emerging data suggest a prominent role of intestinal microbiota; however, contributions of pathogenic gut microbiota such as Clostridium difficile are not well defined. We performed a genome-wide association study (GWAS) to investigate clinical and genetic factors associated with development of LGAE.

METHODS

A total of 972 patients undergoing autologous SCT were graded for LGAE based on Common Terminology Criteria for Adverse Events (v 4.0). Germline DNA material was obtained from leukapharesis products and genotyped using Illumina(®) Whole Genome Genotyping Infinium chemistry and HumanOmni1-Quad Bead chips containing over 1.1 million single nucleotide polymorphisms (SNPs) (Illumina, San Diego, California, USA). Statistical models incorporating clinical factors, genetic factors, and a combination of clinical plus genetic factors were utilized to compare patients who developed severe LGAE (grade 2 or above) and others.

RESULTS

Among 972 patients, 459 (47.2%) developed severe LGAE. Baseline hemoglobin and hematocrit, estimated glomerular filtration rate, β2-microglobulin, protocol type, and C. difficile infection (CDI) were associated with severe LGAE on univariate analysis, Genomic comparisons between groups did not reveal any SNPs associated with severe LGAE and neither did incorporation of genetic factors into the clinical model. In addition, 11 candidate SNPs associated with upper GI mucositis were evaluated, alongside clinical factors in a multivariate model. Only CDI was found to be associated with severe LGAE in all models.

CONCLUSION

CDI is a prominent factor in the development of LGAE in patients undergoing autologous SCT.

Fecal microbiota transplantation (FMT) for Clostridium difficile infection: focus on immunocompromised patients

Clostridium difficile infection (CDI) is an emerging problem worldwide associated with significant morbidity, mortality, recurrence rates and healthcare costs. Immunosuppressed patients, including HIV-seropositive individuals, solid organ transplant recipients, patients with malignancies, hematopoietic stem cell transplant recipients, and patients with inflammatory bowel disease are increasingly recognized as being at higher risk of developing CDI where it may be associated with significant complications, recurrence, and mortality. Fecal microbiota transplantation (FMT) has proven to be an effective and safe procedure for the treatment of recurrent or refractory CDI in immunocompetent patients by restoring the gut microbiota and resistance to further recurrences. During the last two years the first data on FMT in immunocompromised patients began to appear in the medical literature. Herein we summarize the use of FMT for the treatment of CDI with a focus on immunocompromised patients.

Risk factors, outcomes and epidemiology associated with Clostridium difficile infection in patients with haematological malignancies in a tertiary care hospital in China

The purpose of this study was to evaluate the risk factors, outcomes and epidemiology associated with Clostridium difficile infection (CDI) in patients with haematological malignancies in a tertiary care hospital in China. C. difficile screening was performed on patients admitted for chemotherapy or haematopoietic stem cell transplantation between 2009 and 2013. C. difficile isolates were analysed by multilocus sequence typing, and a retrospective chart review was performed on all patients with a positive toxin assay. CDI was diagnosed in 21 haematology-oncology ward patients and 14 marrow transplantation service patients for a cumulative incidence of 1.89/1000 and 3.69/1000 patient-days, respectively. Univariate analyses showed that patients who received etoposide had an increased risk of CDI (odds ratio 4.25, 95 % confidence interval 1.32-13.64). There was only one patient death, for which CDI was not the primary cause. Ten sequence types (STs) were identified, of which ST-3 and ST-54 were the most common; the hypervirulent ST-1 (ribotype 027) and ST-11 (ribotype 078) C. difficile strains were not detected in the patients in this study. The incidence of CDI did not differ between patients receiving chemotherapy and those receiving haematopoietic stem cell transplantation. The only risk factor for chemotherapy patients was treatment with etoposide.

Clostridium difficile

Clostridium difficile has re-emerged as a major hospital-acquired infection since 2001. Despite development of polymerase chain reaction-based testing, no single clinical diagnostic test has emerged with sufficient sensitivity, specificity, and turnaround time to be entirely reliable for disease diagnosis. The importance of C difficile acquired outside the hospital environment remains an unknown factor and awaits further epidemiologic investigation. This article discusses the changing epidemiology, clinical presentation, and pathogenesis of C difficile infection and highlights the ongoing challenges of laboratory diagnosis, treatment, and disease relapse.