Risk factors associated with Clostridium difficile infection in kidney transplant recipients

The impact of Clostridioides difficile infection on outcomes among kidney transplant recipients

BACKGROUND

Clostridioides difficile infection (CDI) is a significant cause of morbidity and mortality among hospitalized patients, particularly those who are immunosuppressed. We aim to assess the outcomes of CDI among kidney transplant (KT) recipients.

METHODS

Nationwide Inpatient Sample from 2016 to 2020 was used to identify patients with KT and stratify based on the presence of CDI. Data were collected regarding demographics and comorbidities. Outcomes included in-hospital mortality, acute kidney injury, intensive care unit admission, transplant rejection, transplant failure, length of stay, and total hospitalization charges. The relationships between variables of interest and outcomes were analyzed using multivariate regression.

RESULTS

A total of 557,635 KT recipients were included. CDI prevalence was 2.4%. The majority of patients in the CDI group were age >65 (43.6%), female (51%), White (55.3%), and had Medicare insurance (74.9%). On multivariate regression analysis, CDI was associated with increased odds of acute kidney injury (aOR 2.06, p < 0.001), intensive care unit admission (aOR 2.47, p < 0.001), and mortality (aOR 1.90, p < 0.001). CDI was also associated with longer length of stay (9.35 days vs 5.42 days, p < 0.001) and higher total hospitalization charges ($110,063 vs $100,006, p < 0.001). There was no difference in transplant rejection, complication, failure, or infection among KT recipients with CDI and those without.

CONCLUSIONS

We found that CDI was associated with worse outcomes and higher costs. KT patients should be monitored closely for signs of CDI in order to initiate appropriate management.

Clostridioides difficile Infection in Kidney Transplant Recipients

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

Diagnosis, Prevention, and Treatment of Infections in Kidney Transplantation

Kidney transplant often is complicated by infections in the recipient from therapy-related and patient-related risk factors. Infections in kidney transplant recipients are associated with increased morbidity, mortality, and allograft dysfunction. There is a predictable timeline after kidney transplant regarding the types of pathogens causing infections, reflecting the net state of immunosuppression. In the early post-transplant period, bacterial infections comprise two thirds of all infections, followed by viral and fungal infections. Infections occurring early after kidney transplantation are generally the result of postoperative complications. In most cases, opportunistic infections occur within 6 months after kidney transplantation. They may be caused by a new infection, a donor-derived infection, or reactivation of a latent infection. Community-acquired pneumonia, upper respiratory tract infections, urinary tract infections, and gastrointestinal infections are the most common infections in the late period after transplantation when the net immunosuppression is minimal. It is crucial to seek information on the time after transplant, reflecting the net state of immunosuppression, previous history of exposure/infections, geography, and seasonal outbreaks. It is imperative that we develop regionally specific guidelines on screening, prevention, and management of infections after kidney transplantation.

Clostridioides difficile infection in solid organ and hematopoietic stem cell transplant recipients: A prospective multinational study

BACKGROUND

Clostridioides difficile infection (CDI) is a significant cause of morbidity and mortality in recipients of solid organ transplant (SOT) or hematopoietic stem cell transplant (HSCT). In retrospective single center analyses, severe disease and relapse are common. We undertook an international, prospective cohort study to estimate the response to physician determined antibiotic treatment for CDI in patients with SOT and HSCT.

METHODS

Adults with a first episode of CDI within the first 2 years of SOT or HSCT were enrolled. Demographics, comorbidities, and medication history were collected, and over 90 days of follow-up clinical cure, recurrences, and complications were assessed. Logistic regression was used to study associations of baseline predictors of clinical cure and recurrence. Odds ratios (ORs) and 95% confidence intervals (CIs) are cited.

RESULTS

A total of 132 patients, 81 SOT and 51 HSCT (32 allogeneic), were enrolled with a median age of 56 years; 82 (62%) were males and 128 (97%) were hospitalized at enrollment. One hundred and six (80.3%) were diagnosed by DNA assay. CDI occurred at a median of 20 days post-transplant (interquartile range, IQR: 6-133). One hundred and eight patients (81.8%) were on proton pump inhibitors; 126 patients (95.5%) received antibiotics within the 6 weeks before CDI. The most common initial CDI treatments prescribed, on or shortly before enrollment, were oral vancomycin alone (50%) and metronidazole alone (36%). Eighty-three percent (95% CI: 76, 89) of patients had clinical cure; 18% (95% CI: 12, 27) of patients had recurrent CDI; global clinical cure occurred in 65.2%. Of the 11 patients who died, two (1.5% of total) were related to CDI. In multivariable logistic regression analyses, the type of initial treatment was associated with clinical cure (p = .009) and recurrence (p = .014). A history of cytomegalovirus (CMV) after transplant was associated with increased risk of recurrence (44% with versus 13% without CMV history; OR: 5.7, 95% CI: 1.5, 21.3; p = .01).

CONCLUSIONS

Among adults who develop CDI after SOT or HSCT, despite their immunosuppressed state, the percentage with clinical cure was high and the percentage with recurrence was low. Clinical cure and recurrence varied by type of initial treatment, and CMV viremia/disease was associated with an increased risk of recurrence.

Anti-virulence strategies for Clostridioides difficile infection: advances and roadblocks

Clostridioides difficile infection (CDI) is a common healthcare- and antibiotic-associated diarrheal disease. If mis-diagnosed, or incompletely treated, CDI can have serious, indeed fatal, consequences. The clinical and economic burden imposed by CDI is great, and the US Centers for Disease Control and Prevention has named the causative agent, C. difficile (CD), as an Urgent Threat To US healthcare. CDI is also a significant problem in the agriculture industry. Currently, there are no FDA-approved preventives for this disease, and the only approved treatments for both human and veterinary CDI involve antibiotic use, which, ironically, is associated with disease relapse and the threat of burgeoning antibiotic resistance. Research efforts in multiple laboratories have demonstrated that non-toxin factors also play key roles in CDI, and that these are critical for disease. Specifically, key CD adhesins, as well as other surface-displayed factors have been shown to be major contributors to host cell attachment, and as such, represent attractive targets for anti-CD interventions. However, research on anti-virulence approaches has been more limited, primarily due to the lack of genetic tools, and an as-yet nascent (but increasingly growing) appreciation of immunological impacts on CDI. The focus of this review is the conceptualization and development of specific anti-virulence strategies to combat CDI. Multiple laboratories are focused on this effort, and the field is now at an exciting stage with numerous products in development. Herein, however, we focus only on select technologies (Figure 1) that have advanced near, or beyond, pre-clinical testing (not those that are currently in clinical trial), and discuss roadblocks associated with their development and implementation.

Gastrointestinal pathogen colonization and the microbiome in asymptomatic kidney transplant recipients

BACKGROUND

In kidney transplant recipients, gastrointestinal (GI) pathogens in feces are only evaluated during diarrheal episodes. Little is known about the prevalence of GI pathogens in asymptomatic individuals in this population.

METHODS

We recruited 142 kidney transplant recipients who provided a non-diarrheal fecal sample within the first 10 days after transplantation. The specimens were evaluated for GI pathogens using the BioFire^® FilmArray^® GI Panel (BioFire Diagnostics, LLC), which tests for 22 pathogens. The fecal microbiome was also characterized using 16S rRNA gene sequencing of the V4-V5 hypervariable region. We evaluated whether detection of Clostridioides difficile and other GI pathogens was associated with post-transplant diarrhea within the first 3 months after transplantation.

RESULTS

Among the 142 subjects, a potential pathogen was detected in 43 (30%) using the GI Panel. The most common organisms detected were C difficile (n = 24, 17%), enteropathogenic Escherichia coli (n = 8, 6%), and norovirus (n = 5, 4%). Detection of a pathogen on the GI panel or detection of C difficile alone was not associated with future post-transplant diarrhea (P > .05). The estimated number of gut bacterial species was significantly lower in subjects colonized with C difficile than those not colonized with a GI pathogen (P = .01).

CONCLUSION

Colonization with GI pathogens, particularly C difficile, is common at the time of kidney transplantation but does not predict subsequent diarrhea. Detection of C difficile carriage was associated with decreased microbial diversity and may be a biomarker of gut dysbiosis.

Impact of asymptomatic bacteriuria incidence and management post-kidney transplantation

OBJECTIVE

Urinary tract infections (UTIs) are the most commonly occurring infectious complication following kidney transplantation. Questions remain regarding whether asymptomatic bacteriuria (ASB) should be treated. The aim was to evaluate the incidence and management of ASB in kidney transplant recipients at a large academic medical center.

METHODS

All subjects receiving an isolated kidney transplant between September 2012 and October 2016, and with at least one ASB episode were included. Demographics, symptomatology, and urine culture data were collected on subjects with bacteriuria in the first year post-transplant. Cultures were classified by symptoms, ASB treatment trends were analyzed, and ASB-to-UTI progression was compared between ASB treatment and non-treatment.

RESULTS

A total of 527 subjects were transplanted with 64 developing at least one ASB episode. The incidence of ASB was 12.1% and treated 74.6% of the time. Neither lack of ASB treatment (P = 0.463) nor ASB within the first month post-transplant (P = 0.303) were associated with ASB-to-UTI progression.

CONCLUSION

Despite high ASB treatment rate, this was not found to be protective against ASB-to-UTI progression. ASB within the first month post-transplant also did not correlate with increased progression risk. These results suggest minimization of ASB treatment in kidney transplant recipients remains an important antimicrobial stewardship target.

Epidemiology, Risk Factors, and Outcomes After Early Posttransplant Clostridiodes difficile Infection in Renal Transplant Recipients

BACKGROUND

Modifiable risk-factors associated with Clostridioides difficile infection (CDI) in renal-transplant (RTX) have not been clearly established and peri-transplant risk has not been described.

OBJECTIVE

Evaluate epidemiology, risk-factors and outcomes after CDI occurring in the first 90 days after RTX (CDI-90).Methods: Observational cohort study/survival analysis of adult RTX recipients from 1/1/2012-12/31/2015. Primary outcome was CDI-90 incidence/risk-factors. Secondary outcome was evaluation of post-90 day transplant outcomes.

RESULTS

982 patients met inclusion criteria; 46 with CDI-90 and 936 without (comparator). CDI incidence in the total population was 4.7% at 90 days, 6.3% at 1 year, and 6.4% at 3 years. Incidence of CDI-90 was 5%; time to diagnosis was 19.4±25 days (median 7). Risk-factors for CDI-90 were alemtuzumab induction (Hazard ratio [HR] 1.5, 95% CI(1.1-2.0), p = 0.005) and age at transplant (HR 1.007/year, 95% CI (1.002-1.012), p= 0.007). However, risk-factors for CDI at any time were different; donation-after-circulatory-death (DCD) donor (HR 2.5 95% CI (1.3-4.9), p = 0.008) and female gender (HR 1.6 95% CI (1.0-2.7), p = 0.049). On Kaplan-Meier, CDI-90 appeared to have an impact on patient/graft survival, however when analyzed in a multivariable stepwise Cox proportional hazards model, only age was significantly associated with survival (p = 0.002).

CONCLUSION AND RELEVANCE

Incidence of CDI-90 is low, mostly occurring in the first post-operative month. Risk-factors vary temporally based on time from transplant. In the early post-op period induction agent and age at transplant are significant, but not after. Associations between CDI and negative graft outcomes appear to be largely driven by age. Future studies validating these risk-factors as well as targeted prophylaxis strategies and their effect on long term graft outcomes and the host microbiome are needed.

Are Clostridium difficile toxins nephrotoxic?

Clostridium difficile-associated disease (CDAD) occurs along a spectrum from simple uncomplicated enteritis to a multi-system disease which may include nephropathy. Pathology is attributed to bacterial toxins, but it is unclear if the latter are directly nephrotoxic. Anecdotes of renal disease from human biopsy findings suggest a variation of histopathologies, but data are relatively limited. Acute renal failure does occur in patients with advanced morbidity. CDAD can complicate chronic renal failure. Kidney tissue culture cytotoxicity has long been known. Kidney function alterations among animal models or diseased humans are relatively uncommon in mild to moderate enteritis. Rare findings of toxinemia are reported. Some have proposed that renal dysfunction arises more from pre-renal compromises. Direct toxin studies on whole kidney are sparse. The role of direct toxin-associated renal disease is worthy of further investigation given the current impetus towards the development of protective and therapeutic passive and active immunity. Hypotheses of toxin-direct or pre-renal toxin compromise of renal function prevail.

Early Emergency General Surgery Is Associated with a Higher Incidence of Clostridium difficile Infection

BACKGROUND

Clostridium difficile infection (CDI) is an important surgical complication. Emergency general surgery (EGS) is a developing area of the acute care surgical practice. Few studies evaluating the incidence and risk factors of CDI in this patient population are available.

PATIENTS AND METHODS

A prospectively maintained Acute and Critical Care Surgery registry spanning from 2008 to 2015 was queried for cases of operative EGS with clinical suspicion of CDI post-operatively. Diagnosis of CDI was made using toxin A/B assay in stools. Demographics, co-morbidities, surgical procedures, length of stay (LOS), intensive care unit LOS, antibiotic use, and death were obtained. The patients positive and negative for CDI were compared using chi-squared and Student's t-test. Multi-variable logistic regression was used to determine risk factors for CDI.

RESULTS

A total of 550 patients were identified. The total incidence of CDI was 12.7%. There was no significant difference in demographics between CDI positive and negative patients. Average time to CDI diagnosis was 10.1 ± 8.5 days post-operatively. Patients who received three or more antibiotic classes were at higher risk of CDI developing post-operatively (83% vs. 75%, p = 0.04). The CDI positive patients underwent an EGS significantly earlier than CDI negative patients (0.9 ± 2.3 vs. 3.2 ± 9.2 days, p < 0.001). The most common procedures were partial colectomies (21.4%); small bowel resections/repairs (12.9%); gastric repair for perforated peptic ulcer (10%); skin and soft tissue procedure (7.1%), and laparotomies (5.7%). There was no difference in outcomes between the groups. On linear regression, an EGS performed later after admission was an independent risk factor for lower CDI (OR 0.87; CI 95% [0.79-0.96], p < 0.01).

CONCLUSION

Patients undergoing an early EGS have a high incidence of CDI. The number of antibiotic classes administered post-operatively affects CDI status. Bowel resections appear to be at increased risk for CDI. Clinicians should have a high index of suspicion and low threshold for testing C. difficile in high-risk EGS patients.