Clostridium difficile in solid organ transplant recipients

Fecal Microbiota Transplantation Donor Screening Updates and Research Gaps for Solid Organ Transplant Recipients

In this review, we discuss stool donor screening considerations to mitigate potential risks of pathogen transmission through fecal microbiota transplant (FMT) in solid organ transplant (SOT) recipients. SOT recipients have a higher risk for Clostridioides difficile infection (CDI) and are more likely to have severe CDI. FMT has been shown to be a valuable tool in the treatment of recurrent CDI (RCDI); however, guidelines for screening for opportunistic infections transmitted through FMT are underdeveloped. We review reported adverse effects of FMT as they pertain to an immunocompromised population and discuss the current understanding and recommendations for screening found in the literature while noting gaps in research. We conclude that while FMT is being performed in the SOT population, typically with positive results, there remain many unanswered questions which may have major safety implications and warrant further study.

Early Clostridioides difficile infection characterizations, risks, and outcomes in allogeneic hematopoietic stem cell and solid organ transplant recipients

BACKGROUND

Clostridioides difficile infection (CDI) frequently complicates allogeneic hematopoietic stem cell (allo-HCT) and solid organ transplantation (SOT).

METHODS

We retrospectively analyzed risk factors and outcomes of CDI occurring within 30 days of transplant.

RESULTS

Between March 2010 and June 2015, 466 allo-HCT and 1454 SOT were performed. The CDI cumulative incidence (95% CI) was 10% (8-13) and 4% (3-5), following allo-HCT and SOT, respectively (p < .01), occurring at a median (range) 7.5 days (1-30) and 11 (1-30), respectively (p = .18). In multivariate analysis, fluoroquinolones use within 14 days pre-transplantation was a risk factor for CDI following allo-HCT (HR 4.06 [95% CI 1.31-12.63], p = .02), and thoracic organ(s) transplantation was a risk factor for CDI following SOT (HR 3.03 [95% CI 1.31-6.98]) for lung and 3.90 (1.58-9.63) for heart and heart/kidney transplant, p = .02. Compared with no-CDI patients, the length of stay (LOS) was prolonged in both allo-HCT (35 days [19-141] vs. 29 [13-164], p < .01) and SOT with CDI (16.5 [4-101] vs. 7 [0-159], p < .01), though not directly attributed to CDI. In allo-HCT, severe acute graft-versus-host disease (aGVHD) occurred more frequently in patients with CDI (33.3% vs. 15.8% without CDI, p = .01) and most aGVHD (87.5%) followed CDI. Non-relapse mortality or overall survival, not attributed to CDI, were also similar in both allo-HCT and SOT.

CONCLUSIONS

Early post-transplant CDI is frequent, associated with fluoroquinolones use in allo-HCT and the transplanted organ in SOT, and is associated with longer LOS in both the groups without difference in survival but with increased aGVHD in allo-HCT.

The burden of Clostridioides difficile infection in patients with history of liver transplant and during index admission

BACKGROUND/OBJECTIVES

Liver transplant recipients have an increased risk of Clostridioides difficile infection (CDI) which associated with higher morbidity and mortality. CDI in liver transplant has been argued to increase hospital costs, charges, and length of stay (LOS) in small studies. However, no recent nationwide analysis determines these outcomes.

METHODS

This is a retrospective cohort study using the National Inpatient Sample 2016. All patients with ICD10CM diagnostic codes for CDI were included. The cohort was stratified for the history of liver transplant and liver transplant index admission. The primary outcome was the odds of CDI in both patient cohorts to patients without liver transplant. Secondary outcomes were inpatient morbidity, mortality, resource utilization, colectomy rates, LOS, and total hospital costs and charges.

RESULTS

A total of 360 364 patients with CDI were identified, 1665 had a history of liver transplant and 155 had liver transplant during that admission. Patients with a history of liver transplant had increased odds of CDI compared to patients with no history of liver transplant (adjusted odds ratio 2.78; 95% confidence interval, 2.44-3.16). Patients with CDI had greater odds of shock, acute kidney injury, ICU stay, organ failure and significantly higher costs, charges and LOS.

CONCLUSIONS

Patients with a history of liver transplant increased odds of CDI. CDI with history of liver transplant and the index admission for liver transplant had higher odds of morbidity and resource utilization. Clinicians must maintain a high index of suspicion for CDI for early diagnosis and appropriate initiation of treatment.

Clostridium difficile infection after pediatric solid organ transplantation: a practical single-center experience

BACKGROUND

During the last two decades, there has been a worldwide increase in frequency and severity of infections with Clostridium difficile (CDI). Solid organ transplant (SOT) recipients receiving immunosuppressing medications are especially at risk.

METHODS

We collected data from immunocompromised pediatric patients, including kidney and liver transplant recipients, at our tertiary pediatric care center in Germany. For this, we performed a retrospective review of institutional databases and analyzed data from all children who underwent diagnostic tests for CDI in a 3-year study period.

RESULTS

A total of 797 diagnostic tests in 343 patients were performed. We found 104 infection episodes in 69 patients (42% female, ages 12 days-20 years). Children after SOT accounted for 20% of all detected CDI patients in our series. Median time of CDI onset after transplantation was 588 days. Overall antibiotic exposure was identified as the major risk factor, particularly in immunocompromised children after SOT (exposure in > 95% of all cases).

CONCLUSIONS

The occurrence of CDI in the pediatric SOT population contributes to a greater length of stay and higher hospital charges. However, only very few severe complications from CDI were observed in our cohort. A potentially fulminant course of CDI can be prevented in most cases if timely diagnosis and treatment are carried out.

Pancreatic disease patients are at higher risk for Clostridium difficile infection compared to those with other co-morbidities

Background

Surveillance of Clostridium difficile infection (CDI) in patients with underlying diseases is important because use of prophylactic antibiotics makes them prone to CDI. Epidemiology of CDI in this high-risk population is poorly understood. A study was conducted to evaluate the impact of CDI in patients with specific underlying co-morbidities.

Method

A total of 2036 patients, whose fecal samples were processed for C. difficile toxin A and B assay by ELISA formed the basis of study. Patients with underlying diseases were classified based on the organ/kind of disease as pancreatic (n = 340), renal (n = 408), hepatic (n = 245), malignant (n = 517) and miscellaneous disease (n = 526). Laboratory records of clinical and demographic details were reviewed. The association of CDI with age, gender, antibiotic receipt, clinical symptoms and underlying co-morbidities was analyzed. Variation in CDI cases based on age groups was also investigated.

Result

Clostridium difficile toxin positivity was 21.6% in general, whereas it was 30.6% in the pancreatic, 17.9% in the renal, 19.6%, in the hepatic, 21.3% in the malignancy and 20.0% in the miscellaneous disease groups. Toxin positivity was the lowest (14.8%) for female gender under renal disease and the highest (31.8%) for patients aged 40 to < 60 years, under pancreatic disease. Bloody diarrhea was a significant predictor for C. difficile toxin positivity. C. difficile toxin status irrespective to the underlying diseases was neither dependent on gender, age-groups or the number of antibiotics used. Association between patients’ gender, age and antibiotics receipt with underlying disease conditions, respective to C. difficile toxin status showed significance in relation to male gender (p < 0.05), age 40 to < 60 years (p = 0.03) and those receiving single (p = 0.09) or multiple antibiotics (p = 0.07).

Conclusion

Pancreatic disease patients are at a higher risk for developing CDI, and particularly male gender, age 40 to < 60 years and those receiving antibiotics are at significant risk.

Fecal microbiota transplantation for the treatment of recurrent and severe Clostridium difficile infection in solid organ transplant recipients: A multicenter experience

Fecal microbiota transplant (FMT) is recommended for Clostridium difficile infection (CDI) treatment; however, use in solid organ transplantation (SOT) patients has theoretical safety concerns. This multicenter, retrospective study evaluated FMT safety, effectiveness, and risk factors for failure in SOT patients. Primary cure and overall cure were defined as resolution of diarrhea or negative C difficile stool test after a single FMT or after subsequent FMT(s) ± anti-CDI antibiotics, respectively. Ninety-four SOT patients underwent FMT, 78% for recurrent CDI and 22% for severe or fulminant CDI. FMT-related adverse events (AE) occurred in 22.3% of cases, mainly comprising self-limiting conditions including nausea, abdominal pain, and FMT-related diarrhea. Severe AEs occurred in 3.2% of cases, with no FMT-related bacteremia. After FMT, 25% of patients with underlying inflammatory bowel disease had worsening disease activity, while 14% of cytomegalovirus-seropositive patients had reactivation. At 3 months, primary cure was 58.7%, while overall cure was 91.3%. Predictors of failing a single FMT included inpatient status, severe and fulminant CDI, presence of pseudomembranous colitis, and use of non-CDI antibiotics at the time of FMT. These data suggest FMT is safe in SOT patients. However, repeated FMT(s) or additional antibiotics may be needed to optimize rates of cure with FMT.

Medical Course and Complications After Lung Transplantation

Lung transplant prolongs life and improves quality of life in patients with end-stage lung disease. However, survival of lung transplant recipients is shorter compared to patients with other solid organ transplants, due to many unique features of the lung allograft. Patients can develop a multitude of noninfectious (e.g., primary graft dysfunction, pulmonary embolism, rejection, acute and chronic, renal insufficiency, malignancies) and infectious (i.e., bacterial, fungal, and viral) complications and require complex multidisciplinary care. This chapter discusses medical course and complications that patients might experience after lung transplantation.

Lactobacillus plantarum 299v Reduces the Incidence of Clostridium difficile Infection in Nephrology and Transplantation Ward-Results of One Year Extended Study

Background: Lactobacillus plantarum 299v (LP299v) is a probiotic strain which influences on the intestinal bacterial flora. This is why, it has been introduced into clinical practice for the prevention and treatment of diarrheal disorders and alleviation of their symptoms in patients during antibiotic therapy. However, the use of probiotics in the prophylaxis of Clostridium difficile infections (CDI) in these patients is problematic. The aim of this clinical, retrospective, single-centre study was to analyse the incidence of CDI among patients hospitalized in the nephrology and transplantation ward in the period before, during and after stopping of LP299v prophylaxis. Methods: Among 5341 patients hospitalized in the nephrology and transplantation ward over a three year period, 34 patients with CDI were diagnosed and included in this analysis. From December 2013 to December 2014 all patients under antibiotic and immunosuppressive therapies received LP299v as a prophylaxis of CDI. The observation period consisted of three twelve-months periods: before, during LP299v use and after stopping of such method of CDI prevention. Results: A significant (p = 0.0003) reduction of CDI incidence during LP299v use (0.11%) was observed compared to two other periods, that is, before and after LP299v use (1.03% and 0.77%, respectively). Conclusions: Routine use of LP299v as a CDI prophylaxis may prevent CDI during antibiotics therapy in patients treated with immunosuppressive agents in nephrology and transplantation ward.

Evaluation of risk factors for a fulminant Clostridium difficile infection after cardiac surgery: a single-center, retrospective cohort study

Background

Clostridium difficile (CD) is the most common pathogen causing nosocomial diarrhea. The clinical presentation ranges from mild diarrhea to severe complications, including pseudomembranous colitis, toxic megacolon, sepsis, and multi-organ failure. When the disease takes a fulminant course, death ensues rapidly in severe and complex cases. Preventive screening or current prophylactic therapies are not useful. Therefore, this study was conducted to detect risk factors for a fulminant CD infection (CDI) in patients undergoing cardiac surgery.

Methods

Between April 1999 and April 2011, a total of 41,466 patients underwent cardiac surgery at our institution. A review of our hospital database revealed 1256 patients (3.0%) with post-operative diarrheal disease who tested positive for CD; these patients comprised the cohort of this observational study. A fulminant CDI occurred in 153 of these patients (12.2%), which was diagnosed on the basis of gastrointestinal complications, e.g. pseudomembranous colitis, and/or the need for post-cardiac surgery laparotomy. Demographic, peri-operative, and survival data were analyzed, and predictors of a fulminant CDI were assessed by binary logistic regression analysis.

Results

The 30-day mortality was 6.1% (n = 77) for the entire cohort, with significantly higher mortality among patients with a fulminant CDI (21.6% vs. 4.0%, p <  0.001). Overall mortality (27.7%, n = 348) was also higher for patients with a fulminant course of the disease (63.4% vs. 22.8%, p <  0.001), and a laparotomy was required in 36.6% (n = 56) of the fulminant cases. Independent predictors of a fulminant CDI were: diabetes mellitus type 2 (OR 1.74, CI 1.15–2.63, p = 0.008), pre-operative ventilation (OR 3.52, CI 1.32–9.35, p = 0.012), utilization of more than 8 units of red blood cell concentrates (OR 1.95, CI 1.01–3.76, p = 0.046) or of more than 5 fresh-frozen plasma units (OR 3.38, CI 2.06–5.54, p <  0.001), and a cross-clamp time > 130 min (OR 1.93, CI 1.12–3.33, p = 0.017).

Conclusions

We identified several independent risk factors for the development of a fulminant CDI after cardiac surgery. Close monitoring of high-risk patients is important in order to establish an early onset of therapy and thus to prevent a CDI from developing a fulminant course after cardiac surgery.

Recent advances in understanding and managing infectious diseases in solid organ transplant recipients

Background: Undergoing solid organ transplantation (SOT) exposes the recipient to various infectious risks, including possible transmission of pathogen by the transplanted organ, post-surgical infections, reactivation of latent pathogens, or novel infections. Recent advances: In the last few years, the emergence of Zika virus has raised concerns in the transplant community. Few cases have been described in SOT patients, and these were associated mainly with moderate disease and favorable outcome; the notable exception is a recent case of fatal meningo-encephalopathy in a heart transplant recipient. Because of the advances in treating hepatitis C, several teams recently started to use organs from hepatitis C-positive donors. The worldwide increasing incidence of multidrug-resistant pathogens, as well as the increasing incidence of Clostridioidesdifficile infection, is of particular concern in SOT patients. In the field of mycology, the main recent therapeutic advance is the availability of isavuconazole for the treatment of invasive aspergillosis and mucormycosis. This drug has the advantage of minimal interaction with calcineurin inhibitors. Regarding the viral reactivations occurring after transplant, cytomegalovirus (CMV) infection is still a significant issue in SOT patients. The management of resistant CMV remains particularly difficult. The approval of letermovir, albeit in bone marrow transplantation, and the therapeutic trial of maribavir bring a ray of hope. Another advancement in management of post-transplant infections is the development of in vitro tests evaluating pathogen-specific immune response, such as immunodiagnostics for CMV and, more recently, tests for monitoring immunity against BK virus. Conclusion: The increasing number of organ transplantations, the use of newer immunosuppressive drugs, and high-risk donors continue to define the landscape of transplant infectious diseases in the current era.

Enhanced Efficacy of High Dose Oral Vancomycin Therapy in Clostridium difficile Diarrhea for Hospitalized Adults Not Responsive to Conventional Oral Vancomycin Therapy: Antibiotic Stewardship Implications

Current therapy of Clostridium difficile diarrhea (CDD) is problematic. Optimal treatment for CDD remains oral vancomycin, but there is little data on oral vancomycin dosing regimens. The objective of this C. difficile diarrhea study was to compare the efficacy of "high dose" vancomycin, 500 mg (PO) q6h, as sole treatment and in those who after 72 h failed to respond to conventional doses of oral vancomycin, 125-250 mg (PO) q6h. Hospitalized adults with CDD were evaluated by various oral vancomycin regimens, i.e., a conventional dose group (125-250 mg (PO) q6h), a "high dose escalation" dose group (250 mg → 500 mg (PO) q6h), and a "high dose" group (500 mg (PO) q6h). Oral vancomycin treatment groups were compared by time to improvement, i.e., decrease in >50% of watery stools/day and duration of therapy. The high dose escalation and high dose oral vancomycin groups showed the most rapid resolution of diarrhea. There was marked decrease in stools/day after "high dose" vancomycin escalation from conventional dosing, i.e., 250 mg (PO) q6h → 500 mg (PO) q6h. This study demonstrated that "high dose" escalation or initial high dose oral vancomycin, i.e., 500 mg (PO) q6h was the most efficacious regimen for CDD.

Identification of Risk Factors Associated With Clostridium difficile Infection in Liver Transplantation Recipients: A Single-Center Analysis

Clostridium difficile remains the leading cause of health care-associated infectious diarrhea, and its incidence and severity are increasing in liver transplant recipients. Several known risk factors for C difficile infection (CDI) are inherently associated with liver transplantation, such as severe underlying illness, immunosuppression, abdominal surgery, and broad-spectrum antibiotic use. We conducted a single-center retrospective case control study to characterize risk factors for CDI among patients who received a liver transplant from January 2008 to December 2012. We also examined the associations of post-transplantation CDI with transplant outcomes. Cases were defined as having diarrhea with a positive test for C difficile by either toxin A/B enzyme immunoassay (EIA) or glutamate dehydrogenase EIA and polymerase chain reaction within 1 year after transplantation. Sixty-five consecutive patients were evaluated, of which 15 (23%) developed CDI. The median time from transplantation to CDI diagnosis was 65 days (interquartile range [IQR] 13-208) and more than one-half (53%) had severe infection. Risk factors that were associated with CDI among liver transplant recipients included: (1) previous history of CDI (20% vs 0%; P = .001); (2) exposure to proton-pump inhibitor therapy (93% vs 60%; P = .015); (3) antimicrobial therapy before transplantation (47% vs 18%; P = .039); (4) a prolonged length of stay before transplantation (1 day [IQR, 1-19] vs 1 day [IQR, 0-1]; P = .028); and (5) chronic kidney disease (53% vs 20%; P = .011). There was no significant differences in patient survivals at 6 months (93% vs 96%; P = .67) and 12 months (87% vs 94%; P = .35) among CDI case and control subjects, respectively.

The Effect of Lactobacillus plantarum 299v on the Incidence of Clostridium difficile Infection in High Risk Patients Treated with Antibiotics

Background:Lactobacillus plantarum 299v (LP299v) has been used in order to reduce gastrointestinal symptoms during antibiotic exposure. However, it remains controversial whether or not probiotics are effective in the prevention of Clostridium difficile infections (CDI) among patients receiving antibiotics. The aim of this study was to analyze the CDI among patients receiving antibiotics and hospitalized in the period before and after starting routine use of LP299v as a prevention of this infection. Methods: Among 3533 patients hospitalized in the nephrology and transplantation ward during a two-year period, 23 patients with CDI were diagnosed and enrolled in this retrospective study. Since November 2013, prevention of CDI with oral use of LP299v was performed in all patients treated with antibiotics and who were at a high risk of developing CDI. The observation period was divided into two twelve-month intervals before and after initiation of the use of LP299v as a prophylactic against CDI. Results: A significant (p = 0.0001) reduction of the number of cases of CDI was found after routinely using LP299v (n = 2; 0.11% of all hospitalized patients) compared with the previous twelve-month period of observation (n = 21; 1.21% of all hospitalized patients). Conclusions: Routine use of LP299v during treatment with antibiotics may prevent C. difficile infection in the nephrology and transplantation ward.

[Nosocomial infection in patients receiving a solid organ transplant or haematopoietic stem cell transplant]

Bacterial infections are the most common infections in solid organ transplant recipients. These infections occur mainly in the first month after transplantation and are hospital-acquired. Nosocomial infections cause significant morbidity and are the most common cause of mortality in this early period of transplantation. These infections are caused by multi-drug resistant (MDR) microorganisms, mainly Gram-negative enterobacteria, non-fermentative Gram-negative bacilli, enterococci, and staphylococci. The patients at risk of developing nosocomial bacterial infections are those previously colonized with MDR bacteria while on the transplant waiting list. Intravascular catheters, the urinary tract, the lungs, and surgical wounds are the most frequent sources of infection. Preventive measures are the same as those applied in non-immunocompromised, hospitalized patients except in patients at high risk for developing fungal infection. These patients need antifungal therapy during their hospitalization, and for preventing some bacterial infections in the early transplant period, patients need vaccinations on the waiting list according to the current recommendations. Although morbidity and mortality related to infectious diseases have decreased during the last few years in haematopoietic stem cell transplant recipients, they are still one of the most important complications in this population. Furthermore, as occurs in the general population, the incidence of nosocomial infections has increased during the different phases of transplantation. It is difficult to establish general preventive measures in these patients, as there are many risk factors conditioning these infections. Firstly, they undergo multiple antibiotic treatments and interventions; secondly, there is a wide variability in the degree of neutropenia and immunosuppression among patients, and finally they combine hospital and home stay during the transplant process. However, some simple measures could be implemented to improve the current situation.

Impact of pretransplant rifaximin therapy on early post-liver transplant infections

Bacterial and fungal infections are major causes of morbidity and mortality after liver transplantation (LT). The role of intestinal decontamination in the prevention of post-LT infections is controversial. Rifaximin is widely used for the treatment of hepatic encephalopathy. The effect of rifaximin on post-LT infections is unknown. The aim of our study was to determine the effect of rifaximin therapy in the pretransplant period on early bacterial infections (EBIs) and fungal infections within the first 30 days after LT. All adult patients who underwent LT at our institution (January 2009 to July 2011) were included in this retrospective cohort study. Patients receiving antibiotics other than pretransplant protocol antibiotics were excluded. Patients were stratified into 2 groups based on the presence or absence of rifaximin therapy for at least 2 days before LT. Infections were defined by the isolation of any bacterial or fungal organisms within 30 days of LT. Multivariate regression analysis, Student t tests, and Pearson's chi-square tests were used to compare the 2 groups. Two hundred sixty-eight patients were included, and 71 of these patients (26.5%) were on rifaximin at the time of LT. The 2 groups were comparable with respect to age, sex, race, and Model for End-Stage Liver Disease score. There were no significant differences in the rates of EBIs (30% for the non-rifaximin group and 25% for the rifaximin group, P = 0.48) or fungal infections between the 2 groups. There was no increase in antimicrobial resistance among the infecting organisms. There was no difference in survival between the rifaximin and non-rifaximin groups (98% versus 97%, P = 0.36). In conclusion, the use of rifaximin in the pre-LT period was not associated with an increased risk of bacterial or fungal infections in the early post-LT period.

Epidemiology of Clostridium difficile infection

There has been dramatic change in the epidemiology of Clostridium difficile infection (CDI) since the turn of the 21st century noted by a marked increase in incidence and severity, occurring at a disproportionately higher frequency in older patients. Historically considered a nosocomial infection associated with antibiotic exposure, CDI has now also emerged in the community in populations previously considered low risk. Emerging risk factors and disease recurrence represent continued challenges in the management of CDI. The increased incidence and severity associated with CDI has coincided with the emergence and rapid spread of a previously rare strain, ribotype 027. Recent data from the United States and Europe suggest that the incidence of CDI may have reached a crescendo in the recent years and is perhaps beginning to plateau. The acute care direct costs of CDI were estimated to be US$4.8 billion in 2008. However, nearly all the published studies have focused on CDI diagnosed and treated in the acute care hospital setting and fail to measure the burden outside the hospital, including recently discharged patients, outpatients, and those in long-term care facilities. Enhanced surveillance methods are needed to monitor the incidence, to identify populations at risk, and to characterize the molecular epidemiology of strains causing CDI.

How to improve the survival of the kidney transplant - is it only the pharmaceutical management?

Kidney transplantation is the best treatment option in chronic kidney disease patients. Despite the new potent immunosuppressants, the long-term graft survival has not significantly improved. This is a rather complex issue with interrelationship between pretransplant donor-recipient variables, recipient post-transplant perioperative non/immunological factors, the combination/dose of maintenance immunosuppression and the general noncompliance of the patient. The recipients with an increased immunological risk should be maintained on triple therapy with steroids, preferably tacrolimus (Tac) or cyclosporine (CsA) plus mycophenolate mofetil (MMF). Eventual calcineurin inhibitor (CNI) minimization should be coupled with either protocol biopsies or frequent biochemistry monitoring including periodical assessment of anti-human leukocyte antigen and donor-specific antibodies. Recipients with standard immunological risks may be considered for as low as possible triple immunosuppression (steroids, Tac/CsA, MMF) after a period of 6 - 12 months. In cases of CNI minimization, a modification with a higher dose of the other two drugs in the triple therapy combination might be considered. The nonadherence to the prescribed maintenance therapy should be regularly checked-up. In conclusion, antibody induction, MMF, steroids and low-dose Tac/CsA should be the mainstream therapy in majority of patients. The short- and mid-term encouraging results for CNI minimization/withdrawal seem to correspond to recent findings of chronic antibody-mediated rejection, and long-term results need further evaluation.

Clinical update for the diagnosis and treatment of Clostridium difficile infection

Clostridium difficile infection (CDI) presents a rapidly evolving challenge in the battle against hospital-acquired infections. Recent advances in CDI diagnosis and management include rapid changes in diagnostic approach with the introduction of newer tests, such as detection of glutamate dehydrogenase in stool and polymerase chain reaction to detect the gene for toxin production, which will soon revolutionize the diagnostic approach to CDI. New medications and multiple medical society guidelines have introduced changing concepts in the definitions of severity of CDI and the choice of therapeutic agents, while rapid expansion of data on the efficacy of fecal microbiota transplantation heralds a revolutionary change in the management of patients suffering multiple relapses of CDI. Through a comprehensive review of current medical literature, this article aims to offer an intensive review of the current state of CDI diagnosis, discuss the strengths and limitations of available laboratory tests, compare both current and future treatments options and offer recommendations for best practice strategies.

Outcomes of Clostridium difficile infection in recipients of solid abdominal organ transplants

Knowledge of outcomes of Clostridium difficile infection (CDI) in solid organ transplant (SOT) recipients is limited. To evaluate this population, we undertook a retrospective cohort study of all recipients of kidney and liver transplants diagnosed with CDI at a single center over 14 yr. Data pertaining to all episodes of CDI were collected. Multivariate analysis using logistic regression was performed to determine independent predictors of clinical cure. Overall, 170 patients developed 215 episodes of CDI. Among these patients, 162 episodes (75%) were cured, and in 103 episodes (48%), patients were cured within 14 d. In a multivariate analysis, lack of clinical cure at 14 d was predicted by recurrent episode (0.21, 95% CI 0.06-0.72, p = 0.0128), treatment with vancomycin (OR 0.27, 95% CI 0.1-0.74, p = 0.011), vasopressor support (OR 0.23, 95% CI 0.07-0.76, p = 0.0161), and CDI before the year 2004 (OR 0.44, 95% CI 0.2-0.98, p = 0.0446). The latter three factors are likely markers for severity of illness. In this cohort, 13 patients (8%) died during hospitalization, and 49 patients (29%) died within one yr. No deaths were attributed to CDI. Recurrent episode was a major predictor of treatment failure, suggesting that research into development of therapeutic options for recurrent disease is needed.

Epidemiology of Clostridium difficile infection

There has been dramatic change in the epidemiology of Clostridium difficile infection (CDI) since the turn of the 21st century noted by a marked increase in incidence and severity, occurring at a disproportionately higher frequency in older patients. Historically considered a nosocomial infection associated with antibiotic exposure, CDI has now also emerged in the community in populations previously considered low risk. Emerging risk factors and disease recurrence represent continued challenges in the management of CDI. The increased incidence and severity associated with CDI has coincided with the emergence and rapid spread of a previously rare strain, ribotype 027. Recent data from the United States and Europe suggest that the incidence of CDI may have reached a crescendo in the recent years and is perhaps beginning to plateau. The acute care direct costs of CDI were estimated to be US$4.8 billion in 2008. However, nearly all the published studies have focused on CDI diagnosed and treated in the acute care hospital setting and fail to measure the burden outside the hospital, including recently discharged patients, outpatients, and those in long-term care facilities. Enhanced surveillance methods are needed to monitor the incidence, to identify populations at risk, and to characterize the molecular epidemiology of strains causing CDI.

Risk factors associated with Clostridium difficile infection after kidney and pancreas transplantation

BACKGROUND

Clostridium difficile infection (CDI) is a common cause of nosocomial antibiotic-associated diarrhea with an increased incidence reported in solid organ transplant recipients. We sought to determine if kidney and/or pancreas transplant recipients possess unique risk factors for CDI.

METHODS

Between January 2009 and February 2011, 942 kidney and 56 pancreas transplants were performed at the 2 centers. Of these, 28 recipients (kidney, n = 24; pancreas, n = 4) developed CDI. Cases were matched to controls (n = 56) in a 1:2 ratio.

RESULTS

Those with CDI were mostly male patients (82% vs. 48%, P = 0.003), deceased-donor organ recipients (86% vs. 64%, P = 0.045), more likely to have leukopenia (18% vs. 4%, P = 0.038), and had undergone a gastrointestinal procedure within 3 months preceding CDI diagnosis (18% vs. 4%, P = 0.038). Cases had higher cumulative and restricted antimicrobial exposure in days (37 ± 79 vs. 8 ± 12, P = 0.009 and 27 ± 69 vs. 7 ± 10, P = 0.032). Cephalosporin use was more common among cases (43% vs. 16%, P = 0.008).

CONCLUSION

Careful antimicrobial selection and assurance of optimal treatment duration in the kidney and pancreas transplant population is prudent. Clinicians should have a heightened awareness of CDI risk particularly during periods of leukopenia and in the setting of gastrointestinal procedures.

Multidrug-resistant bacterial infection in solid organ transplant recipients

The most frequent complication from infection after solid organ transplantation is bacterial infection. This complication is more frequent in organ transplantation involving the abdominal cavity, such as liver or pancreas transplantation, and less frequent in heart transplant recipients. The sources, clinical characteristics, antibiotic resistance and clinical outcomes vary according to the time of onset after transplantation. Most bacterial infections during the first month post-transplantation are hospital acquired, and there is usually a high incidence of multidrug-resistant bacterial infections. The higher incidence of complications from bacterial infection in the first month post-transplantation may be associated with high morbidity. Of special interest due to their frequency are infections by S. aureus, enterococci, Gram-negative enteric and non-fermentative bacilli. Opportunistic bacterial infections may occur at any time on the posttransplant timeline, but are more frequent between months two and six, the period in which immunosuppression is higher. The most frequent bacterial species causing opportunistic infections in organ transplant recipients are Listeria monocytogenes and Nocardia spp. After month six, posttransplantation solid organ transplant patients usually develop conventional community-acquired bacterial infections, especially urinary tract infections by E. coli and S. pneumoniae pneumonia. In this article we review the clinical characteristics, epidemiology, diagnosis and prognosis of bacterial infections in solid organ transplant patients.

Clostridium difficile colitis: increasing incidence, risk factors, and outcomes in solid organ transplant recipients

BACKGROUND

Clostridium difficile-associated diarrhea (CDAD) is an increasingly important diagnosis in solid organ transplant recipients, with rising incidence and mortality. We describe the incidence, risk factors, and outcomes of colectomy for CDAD after solid organ transplantation.

METHODS

Patients with CDAD were identified from a prospective transplant database. Complicated Clostridium difficile colitis (CCDC) was defined as CDAD associated with graft loss, total colectomy, or death.

RESULTS

From 1999 to 2010, we performed solid organ transplants for 1331 recipients at our institution. The incidence of CDAD was 12.4% (165 patients); it increased from 4.5% (1999) to 21.1% (2005) and finally 9.5% (2010). The peak frequency of CDAD was between 6 and 10 days posttransplantation. Age more than 55 years (hazard ratio [HR]: 1.47, 95% confidence interval [CI]=1.16-1.81), induction with antithymocyte globulin (HR: 1.43, 95% CI=1.075-1.94), and transplant other than kidney alone (liver, heart, pancreas, or combined kidney organ) (HR: 1.41, 95% CI=1.05-1.92) were significant independent risk factors for CDAD. CCDC occurred in 15.8% of CDAD cases. Independent predictors of CCDC were white blood cell count more than 25,000/μL (HR: 1.08, 95% CI=1.025-1.15) and evidence of pancolitis on computed tomography scan (HR: 2.52, 95% CI=1.195-5.35). Six patients with CCDC underwent colectomy with 83% patient survival and 20% graft loss. Of the medically treated patients with CCDC (n=20), the patient survival was 35% with 100% graft loss.

CONCLUSIONS

We have identified significant risk factors for CDAD and predictors of progression to CCDC. Furthermore, we found that colectomy can be performed with excellent survival in selected patients.

Clinical approach to severe Clostridium difficile infection: update for the hospital practitioner

The rising incidence of Clostridium difficile (C. difficile) infection or CDI is now a problem of pandemic proportions. The NAP1 hypervirulent strain of C. difficile is responsible for a majority of recent epidemics and the widespread use of fluoroquinolone antibiotics may have facilitated the selective proliferation of this strain. The NAP1 strain also is more likely to cause severe and fulminant colitis characterized by marked leukocytosis, renal failure, hemodynamic instability, and toxic megacolon. No single test suffices to diagnose severe CDI, instead; the clinician must rely on a combination of clinical acumen, laboratory testing, and radiologic and endoscopic modalities. Although oral vancomycin and metronidazole are considered standard therapies in the medical management of CDI, recently it has been demonstrated that vancomycin is the more effective antibiotic in cases of severe disease. Moreover, early surgical consultation is necessary in patients who do not respond to medical therapy or who demonstrate rising white blood cell counts or hemodynamic instability indicative of fulminant colitis. Subtotal colectomy with end ileostomy is the procedure of choice for fulminant colitis. When applied to select patients in a judicious and timely fashion, surgery can be a life-saving intervention. In addition to these therapeutic approaches, several investigational treatments including novel antibiotics, fecal bacteriotherapy and immunotherapy have shown promise in the care of patients with severe CDI.

Critical care issues in patients after liver transplantation

The majority of patients who undergo liver transplantation (LT) spend some time in the intensive care unit during the postoperative period. For some, this is an expected part of the immediate posttransplant recovery period, whereas for others, the stay is more prolonged because of preexisting conditions, intraoperative events, or postoperative complications. In this review, 4 topics that are particularly relevant to the postoperative intensive care of LT recipients are discussed, with an emphasis on current knowledge specific to this patient group. Infectious complications are the most common causes of early posttransplant morbidity and mortality. The common patterns of infection seen in patients after LT and their management are discussed. Acute kidney injury and renal failure are common in post-LT patients. Kidney injury identification, etiologies, and risk factors and approaches to management are reviewed. The majority of patients will require weaning from mechanical ventilation in the immediate postoperative period; the approach to this is discussed along with the approach for those patients who require a prolonged period of mechanical ventilation. A poorly functioning graft requires prompt identification and appropriate management if the outcomes are to be optimized. The causes of poor graft function are systematically reviewed, and the management of these grafts is discussed.

Clostridium difficile infection in cancer patients and hematopoietic stem cell transplant recipients

Clostridium difficile has become the most common bacterial cause of nosocomial diarrhea. High rates of C. difficile infection (CDI) coupled with increasing morbidity and mortality attributed to CDI have sparked a renewed interest in this disease. Emergence of hypervirulent strains, rising rates of severe and recurrent infection and associated infection control challenges, and diagnostic and therapeutic dilemmas are major issues in the non-oncology population. Scant data on CDI exist in the cancer/transplant population. The purpose of this article is to describe the epidemiology, pathogenesis and management of CDI in patients receiving cancer chemotherapeutic agents, and in hematopoietic stem cell transplant recipients.