Infectious complications as the leading cause of death after kidney transplantation: analysis of more than 10,000 transplants from a single center

Persistent Mortality Risk From Device-related Healthcare-associated Infection in Kidney Transplant Recipients Despite Multifaceted Interventions Action Calls for a Zero-tolerance Policy

Background

Although multifaceted control intervention actions (bundles) are highly effective in reducing the risk of device-related healthcare-associated infections (d-HAIs), no studies have explored their impact on the outcomes of kidney transplant recipients (KTRs) or the extent of risk reduction achievable through the bundle implementation.

Methods

Seven hundred ninety-eight prevalent KTRs admitted to the intensive care unit (ICU) requiring invasive devices were included: 449 patients from the bundle preimplementation period and 349 from the postimplementation period. The primary outcome was mortality within 90 d of ICU admission. Using Poisson regression models, the magnitude of risk reduction for d-HAIs after the bundle implementation and the impact of d-HAIs on the risk of death was estimated.

Results

The 90-d survival rate was significantly lower in patients with d-HAIs (37.7% versus 71.7%; P < 0.001). The bundle implementation reduced the risk of d-HAIs by 58% (relative risk, 0.42; P = 0.005). Despite the significant reduction in d-HAIs after the bundle implementation, d-HAIs were associated with a 2.6-fold higher risk of death (hazard ratio [HR], 2.63; P < 0.001) regardless of the study period. Additional variables associated with increased risk of death included age (HR, 1.03; P < 0.001), baseline immunosuppression (HR based on mycophenolate versus others 0.74; P = 0.02), time since transplantation (HR, 1.003; P < 0.001), platelet count at ICU admission (HR, 0.998; P < 0.001), and sepsis as the reason for ICU admission (HR, 1.67; P < 0.001).

Conclusions

The persistent risk associated with d-HAIs, despite the implementation of multifaceted control intervention actions in an ICU specialized in KTR care, underscores the need for a zero-tolerance policy toward d-HAIs.

Infections in Kidney Transplant Recipients: Perspectives in French Caribbean

Few studies have focused on the infectious complications in kidney transplant recipients in tropical regions, particularly in the Caribbean. The primary objective of this study was to determine the incidence of bacterial, fungal, and parasitic infections in kidney transplant recipients in the French Caribbean and French Guiana. We included all patients who received a kidney transplant at the University Hospital of Guadeloupe between January 2014 and October 2016, with post-transplant follow-up in the French Caribbean. A total of 91 patients were included, of whom 57 developed an infectious event during follow-up. When infections were documented (94/111), bacterial infections were the most frequent (79/94), followed by fungal (11/94) and parasitic infections (4/94). Four cases of nocardiosis were identified (4/79). Phaeohyphomycosis was the most common fungal infection (7/11). In a multivariate analysis, the female gender and diabetes mellitus at the time of transplant were significantly associated with a higher risk of infection. This study is the first to describe the epidemiology of infections in kidney transplant recipients in the Caribbean and to analyze the potential risk factors. We reported a similar profile of bacterial infections to that which were observed in the European and American studies. However, we found a higher incidence of tropical infections, such as nocardiosis and phaeohyphomycosis, which highlights the need for heightened awareness among healthcare teams to ensure earlier and more appropriate treatment. Further studies focusing on these rare tropical infections are necessary to better understand their risk factors.

Torquetenovirus Viremia Quantification Using Real-Time PCR Developed on a Fully Automated, Random-Access Platform

Quantification of Torquetenovirus (TTV) viremia is becoming important for evaluating the status of the immune system in solid organ transplant recipients, monitoring the appearance of post-transplant complications, and controlling the efficacy of maintenance immunosuppressive therapy. Thus, diagnostic approaches able to scale up TTV quantification are needed. Here, we report on the development and validation of a real-time PCR assay for TTV quantification on the Hologic Panther Fusion® System by utilizing its open-access channel. The manual real-time PCR previously developed in our laboratories was optimized to detect TTV DNA on the Hologic Panther Fusion® System. The assay was validated using clinical samples. The automated TTV assay has a limit of detection of 1.6 log copies per ml of serum. Using 112 samples previously tested via manual real-time PCR, the concordance in TTV detection was 93% between the assays. When the TTV levels were compared, the overall agreement between the methods, as assessed using Passing-Bablok linear regression and Bland-Altman analyses, was excellent. In summary, we validated a highly sensitive and accurate method for the diagnostic use of TTV quantification on a fully automated Hologic Panther Fusion® System. This will greatly improve the turnaround time for TTV testing and better support the laboratory diagnosis of this new viral biomarker.

Effect of post-transplant diabetes mellitus on cardiovascular events and mortality: a single-center retrospective cohort study

PURPOSE

This study aims to investigate the impact of post-transplant diabetes mellitus (PTDM) on cardiovascular events, graft survival, and mortality and to determine the risk factors involved in developing PTDM.

METHODS

A total of 703 patients who underwent kidney transplantation were included in the study. The total sample was subdivided into three groups: (i) patients with PTDM; (ii) patients who had diabetes before the transplantation (DM); and (iii) patients without diabetes (NoDM). The data on graft failure, cardiovascular events, all-cause mortality, and the potential risk factors that play a role in developing PTDM were recorded and analyzed.

RESULTS

The patients were followed for a median of 80 (6-300) months after transplantation. Out of all patients, 41 (5.8%) had DM before transplantation, and 101 (14.4%) developed PTDM. Recipient BMI, post-transplant fasting plasma glucose, and hepatitis C seropositivity were independent risk factors for PTDM development. The incidence of cardiovascular events was 6.1% in the NoDM group, 14.9% in the PTDM group, and 29.3% in the DM group (p < 0.001). In PTDM patients, hepatitis C seropositivity and the recipient's age at transplant were independent predictors of a cardiovascular event. There were no significant differences between the groups regarding the risk of graft loss. PTDM had no significant effect on all-cause mortality. However, the survival rates of DM patients were significantly reduced compared to those with NoDM or PTDM.

CONCLUSIONS

PTDM had no impact on patient survival. Hepatitis C seropositivity and recipient age at transplant predicted cardiovascular events in PTDM patients.

Peritoneal dialysis after failed kidney allograft: Comparing patients with and without pd before transplant

BACKGROUND

The result of published studies on the clinical outcome of peritoneal dialysis (PD) after kidney allograft failure is conflicting. There are also few published data on the outcome of patients who had PD before kidney transplant and then return to PD after allograft failure.

METHODS

We reviewed 100 patients who were started on PD after kidney allograft failure between 2001 and 2020 (failed transplant group); 50 of them received PD before transplant. We compared the clinical outcome to 200 new PD patients matched for age, sex, and diabetic status (control group).

RESULTS

The patients were followed for 45.8 ± 40.5 months. the 2-year patient survival rate was 83.3% and 87.8% for the failed transplant and control groups, respectively (log rank test, p = 0.2). The corresponding 2-year technique survival rate 66.5% and 71.7% (p = 0.5). The failed transplant and control groups also had similar hospitalization rate and peritonitis rate. In the failed transplant group, there was also no difference in patient survival, technique survival, hospitalization, or peritonitis rate between those with and without PD before transplant. In the failed transplant group, patients who had PD before transplant and then returned to PD after allograft failure had substantial increase in D/P4 (0.585 ± 0.130 to 0.659 ± 0.111, paired t-test, p = 0.032) and MTAC creatinine (7.74 ± 3.68 to 9.73 ± 3.00 ml/min/1.73m2, p = 0.047) from the time before the transplant to the time after PD was resumed after failed allograft.

CONCLUSIONS

The clinical outcome of PD patients with a failed kidney allograft is similar to other PD patients. However, patients who have a history of PD before kidney transplant and then return to PD after allograft failure have increased peritoneal transport parameters.

Regulation of gut microbiota: a novel pretreatment for complications in patients who have undergone kidney transplantation

Kidney transplantation is an effective method to improve the condition of patients with end-stage renal disease. The gut microbiota significantly affects the immune system and can be used as an influencing factor to change the prognoses of patients who have undergone kidney transplantation. Recipients after kidney transplantation showed a lower abundance of Firmicutes and Faecalibacterium prausnitzii and a higher proportion of Bacteroidetes and Proteobacteria. After using prebiotics, synbiotics, and fecal microbiota transplantation to regulate the microbial community, the prognoses of patients who underwent kidney transplantation evidently improved. We aimed to determine the relationship between gut microbiota and various postoperative complications inpatients who have undergone kidney transplantation in recent years and to explore how gut microecology affects post-transplant complications. An in-depth understanding of the specific functions of gut microbiota and identification of the actual pathogenic flora during complications in patients undergoing kidney transplantation can help physicians develop strategies to restore the normal intestinal microbiome of transplant patients to maximize their survival and improve their quality of life.

Effects of Bacterial Urinary Tract Infection on Clinical Outcome and Survival of Kidney Transplant Patients

BACKGROUND

There is no consensus on whether the development of urinary tract infections (UTIs) leads to high mortality or graft loss in kidney transplant patients. A high incidence of multidrug resistant (MDR) infections was observed worldwide and is associated with these complications. The aim of this study was to analyze the effects of UTIs on the clinical outcome and survival in kidney transplant patients.

METHODS

This retrospective study evaluated 601 kidney transplant patients who were categorized as follows: group 1 (G1) patients without a UTI, group 2 (G2) patients with a UTI, and group 3 (G3) recipients with a recurrent UTI. Patients were followed up for at least 1 year after transplantation. Graft survival, risk of graft loss, and risk of developing a UTI were analyzed by the Kaplan-Meier method, Cox regression, and logistic regression methods, respectively. Differences with P < .05 were considered statistically significant.

RESULTS

The proportion of rejection episodes was higher in G3 (32.35%) than in G1 (20.89%) and G2 (21.88%) (P < .001). The graft survival after the 10-year follow-up was better in G1 (73.29%) than in G3 (61.62%) (P = .019). UTI recurrent episodes increased the risk of graft loss >2.5-fold. Women and those who received a kidney from a deceased donor (DD) were at risk of at least 1 UTI event during follow-up. A greater proportion of MDR infections was observed in G3 than in G2 (P < .001).

CONCLUSIONS

The risk factors for developing a UTI were female sex, receiving a DD kidney, susceptibility to other infections, episodes of rejection, and delayed graft function. Moreover, a UTI, especially a recurrent UTI, was an important risk factor for allograft loss.

Survival Rate of Renal Transplant and Factors Affecting Renal Transplant Failure

OBJECTIVES

The most important complication in kidney transplant is acute/chronic rejection. In this study, we investigated the factors affecting kidney rejection and transplant survival.

MATERIALS AND METHODS

In this survival analysis study, 352 patients (mean follow-up of 12.9 ± 4.4 years) who underwent renal biopsy due to increased creatinine level from 2012 to 2016 were identified by glomerular filtration rate level and rejection. Probable factors affecting renal function and survival rate after transplant rejection were assessed. P < .05 was considered as significant.

RESULTS

Among our study patients, 40.9% developed early and 59.1% developed late acute kidney injury. Graft survival rates at 1 and 5 years were 98.9% and 68.5%, respectively, which was significant when rejection type was considered (P = .002). In addition, patient survival rates at 1 and 5 years were 99.7% and 98.6%, respectively. Graft survival at 5 years was significantly lower among older subjects, those with diabetes, those who received deceased donor organs, and those with late acute kidney injury (P < .002). Patient survival was significantly higher among young patients, those with systemic lupus erythematosus, those who received living donor organs, and those without cytomegalovirus infection (P < .003).

CONCLUSIONS

We observed that recipient age, type of donor, underlying disease, infection, and late acute kidney injury had great negative impacts on renal dysfunction and survival. In our center, because of the large number of kidney transplants from deceased donors, the necessity of antithymocyte globulin induction therapy was considered, since this study showed that patients who received rabbit antithymocyte globulin induction had better outcomes.

Association Between Blood and Lymphocyte Levels of Cyclosporin A and Infectious Complications in Renal Transplant Patients

Objectives

This study aims to investigate a potential association between whole blood and lymphocyte Cyclosporin A (CyA) levels and the occurrence and frequency of infectious complications in kidney transplant patients.

Methods

The study involves 130 kidney transplant recipients who received CyA in addition to Mycophenolate Mofetil and steroids. CyA whole blood trough and maximum level (CyA BL₀ and CyA BLm) as well as the corresponding levels in the lymphocytes (CyA L₀ and CyA Lm) were measured for 6 months post-transplantation.

Results

Cytomegalovirus (CMV) as well as urinary tract infections (UTIs) were the most commonly diagnosed with an incidence of 24.6% and 26.2%, respectively. Only CyA L₀ showed a significant association with CMV infection occurrence (adjusted OR = 1.051, 95% CI .997–1.025, P-value 0.046). A positive linear correlation was found between CyA BL₀, CyA BLm and CyA Lm and the number of CMV episodes per patient.

Conclusion

We showed an association between the CMV infections occurrence and the trough lymphocyte level of CyA (CyA L₀). Both lymphocyte CyA levels also correlated with the frequency of CMV infections. Further studies are needed to establish the optimal range of both CyA blood and lymphocyte levels and decrease the risk of opportunistic infections in high risk patients.

What Is the Part of Tropical Diseases Among Infectious Complications in Renal Transplant Recipients in the Amazon? A 12-Year Multicenter Retrospective Analysis in French Guiana

BACKGROUND

Infectious complications in kidney transplant recipients (KTRs) are well studied in temperate countries but remain barely known in tropical ones. The main objective of this study was to describe infection-related hospitalizations in patients living in the Amazon, where it has never been described.

METHODS

All KTRs residing in French Guiana between 2007 and 2018 were included retrospectively. Infection-related hospitalizations were collected in the main medical centers of the territory.

RESULTS

Eighty-two patients were included, and 42 were infected during the study period (51%). Eighty-seven infections were identified. The main sites of infection were urinary, in 29% of cases (25/87), and pulmonary, in 22% of cases (19/87). When documented (48/87), bacterial infections were predominant (35/48), followed by viral (8/48), fungal (4/48), and parasitic infections (1/48). Endemic so-called tropical infections accounted for 6% of infections (5/87). Histoplasma capsulatum was the most commonly isolated fungus (2/4).

CONCLUSIONS

This study suggests that the spectrum of infections in KTRs in French Guiana differs little from that of temperate countries. Nevertheless, some tropical infections are described. More studies on fungal infections in KTRs should be undertaken to clarify the weight of histoplasmosis in these patients.

Differences Between Infectious Disease Events in First Liver Transplant Versus Retransplantation in the Swiss Transplant Cohort Study

Retransplantation after graft failure is increasingly performed, and inferior graft survival, patient survival, and quality of life has been reported. The role of infectious disease (ID) events in this less favorable outcome is unknown. We analyzed ID events after first liver transplantation (FLTpx) and retransplantation (reLTpx) in the Swiss Transplant Cohort Study. Clinical factors were compared after FLTpx and reLTpx, and survival analysis was applied to compare the time to ID events after FLTpx and after reLTpx, adjusted for age, sex, Model for End-Stage Liver Disease score, donor type, liver transplant type (whole versus split liver), and duration of transplant surgery. In total, 60 patients were included (65.0% male, median age of 56 years). Overall, 343 ID events were observed: 204 (59.5%) after the FLTpx and 139 (40.5%) after reLTpx. Bacterial infections were most frequent (193/343, 56.3%), followed by viral (43/343, 12.5%) and fungal (28/343, 8.2%) infections, with less infections by Candida spp. but more by Aspergillus spp. after reLTpx (P = 0.01). The most frequent infection site was bloodstream infection (86, 21.3%), followed by liver and biliary tract (83, 20.5%) and intraabdominal (63, 15.6%) infections. After reLTpx, more respiratory tract and surgical site infections were observed (P < 0.001). The time to first infection was shorter after FLTpx (adjusted hazard ratio [HR], 0.5; 95%-confidence interval [CI], 0.3-1.0; P = 0.04). Reduced hazards for ID events after reLTpx were also observed when modelling recurrent events (adjusted HR, 0.5; CI, 0.3-0.8; P = 0.003). The number of infections was comparable after FLTpx and reLTpx; however, differences regarding infection sites and fungal species were observed. Hazards were reduced for infection after reLTpx.

Risk factors for colonization and infection by resistant microorganisms in kidney transplant recipients

OBJECTIVES

to assess the prevalence of colonization and infection by multidrug-resistant bacteria in patients undergoing kidney transplantation and identify the rate of infection, morbidity and mortality and associated risk factors.

METHODS

a prospective cohort of 200 randomly included kidney transplant recipients. Epidemiological surveillance of the studied microorganisms was carried out in the first 24 hours and 7 days after transplantation.

RESULTS

ninety (45%) patients were considered colonized. Female sex, hypertension and diabetes (p<0.005), dialysis time (p<0.004), length of stay after transplantation, delayed renal function, and length of stay were identified as risk factors. The microorganisms were isolated from surgical site, bloodstream and urinary tract infections.

CONCLUSIONS

colonization by resistant microorganisms in kidney transplant patients was frequent and risk factors associated with infection were identified. The results should guide the care team in order to minimize morbidity and mortality related to infectious causes in this population.

A large-scale investigation into the role of classical HLA loci in multiple types of severe infections, with a focus on overlaps with autoimmune and mental disorders

Background

Infections are a major disease burden worldwide. While they are caused by external pathogens, host genetics also plays a part in susceptibility to infections. Past studies have reported diverse associations between human leukocyte antigen (HLA) alleles and infections, but many were limited by small sample sizes and/or focused on only one infection.

Methods

We performed an immunogenetic association study examining 13 categories of severe infection (bacterial, viral, central nervous system, gastrointestinal, genital, hepatitis, otitis, pregnancy-related, respiratory, sepsis, skin infection, urological and other infections), as well as a phenotype for having any infection, and seven classical HLA loci (HLA-A, B, C, DPB1, DQA1, DQB1 and DRB1). Additionally, we examined associations between infections and specific alleles highlighted in our previous studies of psychiatric disorders and autoimmune disease, as these conditions are known to be linked to infections.

Results

Associations between HLA loci and infections were generally not strong. Highlighted associations included associations between DQB1*0302 and DQB1*0604 and viral infections (P = 0.002835 and P = 0.014332, respectively), DQB1*0503 and sepsis (P = 0.006053), and DQA1*0301 with “other” infections (a category which includes infections not included in our main categories e.g. protozoan infections) (P = 0.000369). Some HLA alleles implicated in autoimmune diseases showed association with susceptibility to infections, but the latter associations were generally weaker, or with opposite trends (in the case of HLA-C alleles, but not with alleles of HLA class II genes). HLA alleles associated with psychiatric disorders did not show association with susceptibility to infections.

Conclusions

Our results suggest that classical HLA alleles do not play a large role in the etiology of severe infections. The discordant association trends with autoimmune disease for some alleles could contribute to mechanistic theories of disease etiology.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-021-02888-1.

Comparison of outcomes of peritoneal dialysis between patients after failed kidney transplant and transplant-naïve patients: a meta-analysis of observational studies

PURPOSE

The influence of prior failed kidney transplants on outcomes of peritoneal dialysis (PD) is unclear. Thus, we conducted a systematic review and meta-analysis to compare the outcomes of patients initiating PD after a failed kidney transplant with those initiating PD without a prior history of kidney transplantation.

METHODS

We searched PubMed, Embase, CENTRAL, and Google Scholar databases from inception until 25 November 2020. Our meta-analysis considered the absolute number of events of mortality, technical failures, and patients with peritonitis, and we also pooled multi-variable adjusted hazard ratios (HR).

RESULTS

We included 12 retrospective studies. For absolute number of events, our analysis indicated no statistically significant difference in technique failure [RR, 1.14; 95% CI, 0.80-1.61; I²=52%; p = 0.48], number of patients with peritonitis [RR, 1.13; 95% CI, 0.97-1.32; I²=5%; p = 0.11] and mortality [RR, 1.00; 95% CI, 0.67-1.50; I²=63%; p = 0.99] between the study groups. The pooled analysis of adjusted HRs indicated no statistically significant difference in the risk of technique failure [HR, 1.25; 95% CI, 0.88-1.78; I²=79%; p = 0.22], peritonitis [HR, 1.04; 95% CI, 0.72-1.50; I²=76%; p = 0.85] and mortality [HR, 1.24; 95% CI, 0.77-2.00; I²=66%; p = 0.38] between the study groups.

CONCLUSION

Patients with kidney transplant failure initiating PD do not have an increased risk of mortality, technique failure, or peritonitis as compared to transplant-naïve patients initiating PD. Further studies are needed to evaluate the impact of prior and ongoing immunosuppression on PD outcomes.

Long-term outcomes after kidney transplant failure and variables related to risk of death and probability of retransplant: Results from a single-center cohort study in Brazil

Background

Returning to dialysis after kidney graft loss (GL) is associated with a high risk of mortality, mainly in the first 3–6 months. The follow-up of patients with GL should be extended to better understand crude patient outcomes, mainly in emerging countries, where the transplantation activity has increased.

Methods

This is a historical single-center cohort study conducted in an emerging country (Brazil) that included 115 transplant patients with kidney allograft failure who were followed for 44.1 (21.4; 72.6) months after GL. The outcomes were death or retransplantation after GL calculated by Kaplan-Meier and log-rank tests. Proportional hazard ratios for death and retransplantation were assessed by Cox regression.

Results

The 5-year probability of retransplantation was 38.7% (95% CI: 26.1%-51.2%) and that of death was 37.7% (95% CI: 24.9%-50.5%); OR = 1.03 (95% CI: 0.71–1.70) and P = 0.66. The likelihood of retransplantation was higher in patients who resumed dialysis with higher levels of hemoglobin (HR = 1.22; 95% CI = 1.04–1.43; P = 0.01) and lower in blood type O patients (HR = 0.48; 95% CI = 0.25–0.93; P = 0.03), which was associated with a lower frequency of retransplantation with a subsequent living-donor kidney. On the other hand, the risk of death was significantly associated with Charlson comorbidity index (HR for each point = 1.37; 95% CI 1.19–1.50; P<0.001), and residual eGFR at the time when patients had resumed to dialysis (HR for each mL = 1.14; 95% CI = 1.05–1.25; P = 0.002). The trend toward a lower risk of death when patients had resumed to dialysis using AV fistula access was observed (HR = 0.50; 95% CI 0.25–1.02; P = 0.06), while a higher risk seems to be associated with the number of previous engraftment (HR = 2.01; 95% CI 0.99–4.07; P = 0.05).

Conclusions

The 5-year probability of retransplantation was not less than that of death. Variables related to the probability of retransplantation were hemoglobin level before resuming dialysis and ABO blood type, while the risk of death was associated with comorbidities and residual eGFR.

Human pegivirus-1 infection in kidney transplant recipients: A single-center experience

Kidney transplantation is the treatment of choice for patients with end-stage renal disease. In the posttransplant period, the induced immunosuppression leads to an increased risk of developing infectious diseases, a leading cause of death after kidney transplantation. Human pegivirus-1 (HPgV-1) is considered a nonpathogenic human virus and is highly frequent in individuals parenterally exposed, however, its impact on kidney transplantation outcome is poorly understood. Given the scarcity of epidemiological data for this infection on organ recipients in Brazil, we conducted a study in a single center for kidney transplantation in Rio de Janeiro, aiming to determine HPgV-1 prevalence and genotypic distribution. Serum samples from 61 renal recipients, followed up for the first year after transplantation, were evaluated for viral RNA and genotypes were determined by sequencing of the 5'-untranslated region. HPgV-1 RNA was detected in 36.1% (22/61) of patients. Genotype 2 was the most commonly found (80.9%), followed by genotypes 3 (9.5%), 1, and 5, in 4.8% each. Statistical comparisons did not reveal any significant impact of HPgV-1 in patient outcome. Further epidemiologic studies are needed to understand if immunosuppression may interfere in HPgV-1 persistence rates and if viremia might impact graft dysfunction rates in kidney recipients.

Mesangial expansion at 5 years predicts death and death-censored graft loss after renal transplantation

Death with a functioning graft and death-censored renal allograft failure remain major problems for which effective preventative protocols are lacking. The retrospective cohort study aimed to determine whether histologic changes on a 5-year surveillance kidney biopsy predict adverse outcomes after transplantation in recipients who had: both Type 2 diabetes (T2DM) and obesity (BMI ≥ 30 kg/m² ) at the time of transplantation (T2DM/Obesity, n = 75); neither (No T2DM/No obesity, n = 78); No T2DM/Obesity (n = 41), and T2DM/No obesity (n = 47). On 5-year biopsies, moderate-to-severe mesangial expansion was more common in the T2DM/Obesity group (Banff mm score ≥2 = 49.3%; Tervaert classification MS ≥ 2b = 26.7%) compared to the other groups (p < .001 for both scores). Risk factors included older age, higher BMI, HbA1C, and triglycerides at 1-year post-transplant. Moderate-to-severe mesangial expansion correlated with death with function (HR 1.74 (1.01, 2.98), p = .045 Banff and 1.89 (1.01, 3.51) p = .045 Tervaert) and with death-censored graft loss (HR 3.2 (1.2, 8.8), p = .02 Banff and HR 3.8 (1.3, 11.5), p = .01 Tervaert) over a mean of 11.6 years of recipient follow-up post-transplant. These data suggest that mesangial expansion in recipients with T2DM and obesity may reflect systemic vascular injury and might be a novel biomarker to predict adverse outcomes post renal transplant.

Impact of Combinations of Donor and Recipient Ages and Other Factors on Kidney Graft Outcomes

As the availability of kidneys for transplantation continues to be outpaced by its growing demand, there has been an increasing utilization of older deceased donors in the last decades. Considering that definition of factors that influence deceased donor kidney transplant outcomes is important for allocation policies, as well as for individualization of post-transplant care, the purpose of this study was determine the risks for death censored graft survival and for patient survival conferred by older age of the donor in the context of the age of the recipient and of risk factors for graft and/or patient survival. The investigation was conducted in a single-center cohort of 5,359 consecutive first kidney transplants with adult deceased donors performed on non-prioritized adult recipients from January 1, 2002, to December 31, 2017. Death censored graft survival and patient survival were lower in older donors, whereas graft survival was higher and patient survival was lower in old recipients. The analyses of combinations of donor and recipient ages showed that death censored graft survival was lower in younger recipients in transplants from 18 to 59-year old donors, with standard or extended criteria, but no difference in graft survival was observed between younger and older recipients when the donor was ≥ 60-year old. Patient survival was higher in younger recipients in transplants with younger or older donors. Two to six HLA-A,B,DR mismatches, when compared to 0-1 MM, conferred risk for death-censored graft survival only in transplants from younger donors to younger recipients. Pre-transplant diabetes conferred risk for patient survival only in 50–59-year old recipients, irrespectively, of the age of the donor. Time on dialysis ≥ 10 years was a risk factor for patient survival in transplants with all donor-recipient age combinations, except in recipients with ≥ 60 years that received a kidney from an 18–49-year old donor. In conclusion, the results obtained in this study underline the importance of analyzing the impact of the age of the donor taking into consideration different scenarios.

The urinary microbiome shows different bacterial genera in renal transplant recipients and non-transplant patients at time of acute kidney injury - a pilot study

Background

In the past urine was considered sterile. Through the introduction of next generation sequencing, it has become clear that a urinary microbiome exists. Acute kidney injury (AKI) represents a major threat to kidney transplant recipients. Remarkable changes in the urinary metabolome occur during AKI, which may influence the urinary microbiome. To our knowledge, this is the first study that examines the urinary microbiome in renal transplant recipients (RTX) and non-transplant recipients (nRTX) at time of AKI.

Methods

In this cross-sectional pilot-study the urinary microbiome of 21 RTX and 9 nRTX with AKI was examined. Clean catch morning urine samples were obtained from all patients on the first day of AKI diagnosis. AKI was defined according to KDIGO guidelines. Urinary microbiota and the urinary metabolome during AKI were assessed in one patient. 16S rRNA sequencing was performed. Sequences were processed using UPARSE-pipeline for operational taxonomic units (OTU) and taxon finding.

Results

We successfully extracted and sequenced bacterial DNA from 100% of the urine samples. All 30 patients revealed at least 106,138 reads. 319 OTU and 211 different genera were identified. The microbiotic diversity richness in the RTX group was no different from the nRTX group. Eighteen genera were solely present in nRTX and 7 in RTX.

Conclusions

The urinary microbiome at time of AKI showed different bacterial genera in RTX compared to nRTX. The nRTX group exhibited no different diversity to the RTX group. Irrespective of the status of a previous renal transplantation, the urinary microbiome comprised > 210 different genera. An intraindividual change in microbiota diversity and richness was observed in one study patient during recovery from AKI.

Early Hospital Readmission (EHR) in kidney transplantation: a review article

Early hospital readmission (EHR), defined as all readmissions within 30 days of initial hospital discharge, is a health care quality measure. It is influenced by the demographic characteristics of the population at risk, the multidisciplinary approach for hospital discharge, the access, coverage, and comprehensiveness of the health care system, and reimbursement policies. EHR is associated with higher morbidity, mortality, and increased health care costs. Monitoring EHR enables the identification of hospital and outpatient healthcare weaknesses and the implementation of corrective interventions. Among kidney transplant recipients in the USA, EHR ranges between 18 and 47%, and is associated with one-year increased mortality and graft loss. One study in Brazil showed an incidence of 19.8% of EHR. The main causes of readmission were infections and surgical and metabolic complications. Strategies to reduce early hospital readmission are therefore essential and should consider the local factors, including socio-economic conditions, epidemiology and endemic diseases, and mobility.

Frailty predicts surgical complications after kidney transplantation. A propensity score matched study

Background and objective

Surgical complications after kidney transplantation can lead to catastrophic outcomes. Frailty has been associated with important kidney transplantation outcomes; however, there are no studies assessing this measure of physiological reserve as a specific predictor of surgical complications in this population. Such an assessment was, therefore, the objective of the present study.

Methods

A total of 87 individuals aged ≥ 18 years who underwent kidney transplantation between March 2017 and March 2018 were included. At the time of admission for kidney transplantation, demographic, clinical, and kidney transplantation data were collected, and the frailty score was calculated according to Fried et al., which comprises five components: shrinking, weakness, exhaustion, low activity, and slowed walking speed. Urological, vascular, and general surgical complications were assessed three months later, or until graft loss or death. The propensity score was used to achieve a better homogeneity of the sample, and new analyses were performed in this new, balanced sample.

Results

Of the 87 individuals included, 30 (34.5%) had surgical complications. After propensity score matching, the risk of surgical complications was significantly higher among the frail individuals (RR 2.14; 95% CI 1.01–4.54; p = 0.035); specifically, the risk of noninfectious surgical complications was significantly higher among these individuals (RR 2.50; 95% CI 1.11–5.62; p = 0.017).

Conclusion

The results showed that individuals with some degree of frailty before kidney transplantation were more subject to surgical complications. The calculation of the frailty score for transplant candidates and the implementations of measures to increase the physiological reserve of these patients at the time of kidney transplantation may possibly reduce the occurrence of surgical complications.

Clinical outcomes of incident peritoneal dialysis patients coming from kidney transplantation program: A case-control study

Introduction

Brazil ranks second in the absolute number of transplantations in the world. Despite improvements in graft survival, many patients will progress to graft loss and return to dialysis. Concerns exist regarding adverse clinical outcomes in this population when undergone peritoneal dialysis (PD).

Objective

To compare the occurrence of mortality, technique failure, and peritonitis among incident patients in PD coming from either Tx or pre-dialysis treatment.

Methodology

A retrospective study in which 47 adult patients with Tx failure (Tx group) were matched for age, gender, diabetes mellitus (DM), modality and start year of PD, with 1:1 predialysis patient (nTx group). The Fine-Gray competing risk model was used to analyze mortality and technique failure.

Results

Compared to nTx, the Tx group had a lower body mass index, serum potassium, and albumin concentrations. A higher ferritin level, transferrin saturation and the number of patients with positive serology for viral hepatitis were also observed in the Tx group. In the multivariate analysis, patients of the Tx group had 4.4-times higher risk of death (p = 0.007), with infection as the main cause. Technique failure and peritonitis were similar in both groups.

Conclusion

Previous Tx is a risk factor for mortality but not for technique failure or peritonitis in incident patients on a PD program.

Risk factors and etiology of repeat infection in kidney transplant recipients

Kidney transplantation (KT) is the best therapy available for patients with end-stage renal disease, but postoperative infections are a significant cause of mortality.In this retrospective study the frequency, risk factors, causative pathogens, and clinical manifestations of infection in KT recipients from Beijing Chao-Yang Hospital, Capital Medical University were investigated. Ninety-seven KT recipients who were hospitalized with infection between January 2010 and December 2016 were included. Clinical characteristics, surgery details, laboratory results, and etiology were compared in patients who developed single infection and patients who developed repeated infection (2 or more) after KT.A total of 161 infections were adequately documented in a total of 97 patients, of which 57 patients (58.8%) had 1 infection, 24 (24.7%) had 2, 11 (11.3%) had 3; 3 (3.1%) had 4, and 2 (2.1%) had 5 or more. The most common infection site was the urinary tract (90 infections; 56%), both overall and in the repeated infection group. The most frequently isolated pathogen was Pseudomonas aeruginosa. In the repeated infection patients, in most cases of P. aeruginosa infection (54%) it was cultured from urine. For first infections, a time between KT and infection of ≤ 21 days (area under receiver operating characteristic curve [AUC] 0.636) and a tacrolimus level ≥ 8 ng/mL (AUC 0.663) independently predicted repeat infection. The combination of these two predictive factors yielded an AUC of 0.716, which did not differ statistically significantly from either predictor alone.With regard to first infections after KT, a time between KT and infection of ≤ 21 days, and a tacrolimus level ≥ 8 ng/mL each independently predicted repeated infection in KT recipients.

Impact of Pneumocystis jirovecii pneumonia on kidney transplant outcome

Backgrounds

Pneumocystis jirovecii pneumonia (PCP) remains an important cause of morbidity and mortality in kidney transplant recipients. While the acute phase toxicity in patients with PCP is well-characterized, there is a lack of data on the effects of PCP on long-term graft outcome.

Method

This retrospective observational study analyzed 1502 adult patients who underwent kidney transplantation at Seoul National University Hospital between 2000 and 2017. After a propensity score matching was performed, the graft and survival outcomes were compared between PCP-negative and PCP-positive groups.

Results

A total of 68 patients (4.5%) developed PCP after transplantation. The multivariable Cox analysis showed that positivity for cytomegalovirus and lack of initial oral antibiotic prophylaxis were risk factors of post-transplant PCP. The PCP-positive group had higher hazard ratios of graft failure [adjusted hazard ratio (HR), 3.1 (1.14–8.26); P = 0.027] and mortality [adjusted HR, 11.0 (3.68–32.80); P < 0.001] than the PCP-negative group. However, the PCP event was not related with subsequent development of de novo donor-specific antibodies or pathologic findings, such as T-cell or antibody mediated rejection and interstitial fibrosis and tubular atrophy.

Conclusions

PCP is a risk factor of long-term graft failure and mortality, irrespective of rejection. Accordingly, appropriate prophylaxis and treatment is needed to avoid adverse transplant outcomes of PCP.

Electronic supplementary material

The online version of this article (10.1186/s12882-019-1407-x) contains supplementary material, which is available to authorized users.

Long-Term Outcomes among Kidney Transplant Recipients and after Graft Failure: A Single-Center Cohort Study in Brazil

Background

The results of kidney transplantation are impacted by the categories of events responsible for patient death and graft failure. The objective of this study was to evaluate the causes of death and graft failure and outcomes after graft failure among kidney transplant recipients.

Methodology

A retrospective cohort study was conducted with 944 patients who underwent kidney transplantation. Outcomes were categorized in a managed and hierarchical manner.

Results

The crude mortality rate was 10.8% (n=102): in 35.3% cause of death was infection, in 30.4% cardiovascular disease, and in 15.7% neoplasia and in 6.8%, it was not possible to determine the cause of death. The rate of graft loss was 10.6%. The main causes of graft failure were chronic rejection (40%), acute rejection (18.3%), thrombosis (17.3%), and recurrence of primary disease (16.5%). Failures due to an acute rejection occurred earlier than those due to chronic rejection and recurrence (p<0.0001). As late causes of graft loss, death with the functioning kidney occurred earlier than recurrence and chronic rejection (p=0.008). The outcomes after graft failure were retransplantation in 26.1% and death in 21.4%, at a mean of 25.5 and 21.4 months, respectively.

Conclusion

It was possible to identify more than 90% of the events responsible for the deaths of transplanted patients, predominantly infectious and cardiovascular diseases. Among the causes of graft failure, chronic and acute rejections and recurrence were the main causes of graft failure which were followed more frequently by retransplantation than by death on dialysis.

Updates on urinary tract infections in kidney transplantation

Urinary tract infection (UTI) represents the most common infection after kidney transplantation; it is associated with an increased risk for acute kidney rejection and impaired graft function in the early post-transplant period. Kidney transplant recipients with UTIs are often clinically asymptomatic due to the immunosuppressive therapy; however, asymptomatic bacteriuria may progress to acute pyelonephritis, bacteremia and urosepsis, particularly in the early post-transplant period, that are independent risk factors for short and long-term graft and patient survival. This article reviews the definitions, incidence, risk factors and the management of UTI in kidney transplant recipients; furthermore, the main controversial and still unanswered questions, regarding the causes of recurrent UTIs, adequate use of antibiotics to avoid antibiotic resistance, dosing and timing for prophylaxis and treatment of symptomatic infections, are also discussed. The emerging definition of urinary microbiota introduces new concepts in understanding the complexity of the disease and might represent the future target for therapeutic interventions.

The influence of clinical, environmental, and socioeconomic factors on five-year patient survival after kidney transplantation

INTRODUCTION

The risk of death after kidney transplant is associated with the age of the recipient, presence of comorbidities, socioeconomic status, local environmental characteristics and access to health care.

OBJECTIVE

To investigate the causes and risk factors associated with death during the first 5 years after kidney transplantation.

METHODS

This was a single-center, retrospective, matched case-control study.

RESULTS

Using a consecutive cohort of 1,873 kidney transplant recipients from January 1st 2007 to December 31st 2009, there were 162 deaths (case group), corresponding to 5-year patient survival of 91.4%. Of these deaths, 25% occurred during the first 3 months after transplant. The most prevalent cause of death was infectious (53%) followed by cardiovascular (24%). Risk factors associated with death were history of diabetes, dialysis type and time, unemployment, delayed graft function, number of visits to center, number of hospitalizations, and duration of hospital stay. After multivariate analysis, only time on dialysis, number of visits to center, and days in hospital were still associated with death. Patients who died had a non-significant higher number of treated acute rejection episodes (38% vs. 29%, p = 0.078), higher mean number of adverse events per patient (5.1 ± 3.8 vs. 3.8 ± 2.9, p = 0.194), and lower mean eGFR at 3 months (50.8 ± 25.1 vs. 56.7 ± 20.7, p = 0.137) and 48 months (45.9 ± 23.8 vs. 58.5 ± 20.2, p = 0.368).

CONCLUSION

This analysis confirmed that in this population, infection is the leading cause of mortality over the first 5 years after kidney transplantation. Several demographic and socioeconomic risk factors were associated with death, most of which are not readily modifiable.

Outcomes of cryptococcosis in renal transplant recipients in a less-resourced health care system

BACKGROUND

Cryptococcosis is the second most common cause of invasive fungal infections in renal transplant recipients in many countries, and data on graft outcome after treatment for this infection is lacking in less-resourced health care settings.

METHODS

Data from 47 renal transplant recipients were retrospectively collected at a single institution during a period of 13 years. Graft dysfunction, graft loss, and mortality rates were evaluated. Predictors of mortality and graft loss were estimated.

RESULTS

A total of 38 (97.4%) patients treated with amphotericin B deoxycholate (AMBd) showed graft dysfunction after antifungal initiation and 8 (18.2%) had kidney graft loss. Graft loss within 30 days after cryptococcosis onset was significantly associated with disseminated infection, greater baseline creatinine levels, and graft dysfunction concomitant to AMBd therapy and an additional nephrotoxic condition. The 30-day mortality rate was 19.2% and it was significantly associated with disseminated and pulmonary infections, somnolence at admission, high CSF opening pressure, positive CSF India ink, creatinine levels greater than 2.0 mg/dL at admission, graft dysfunction in patients treated with AMBd and an additional nephrotoxic condition and graft loss within 30 days.

CONCLUSION

Graft dysfunction was common in renal transplant recipients with cryptococcosis treated with AMBd. The rate of graft loss rate was high, most frequently in patients with concomitant nephrotoxic conditions. Therefore, the clinical focus should be on the use of less nephrotoxic lipid formulations of amphotericin B in this specific population requiring a polyene induction regimen for treatment of severe cryptococcosis in all health care systems caring for transplantation recipients.

Immunization in end stage renal disease: The perception of waiting list patients

BACKGROUND

The number of patients with chronic kidney disease is increasing worldwide, as well as the number of patients in kidney transplant waiting lists. In order to prevent infections related to immunosuppressive therapy, immunization guidelines for CKD patients before transplantation have been proposed. The aim of the present study was to evaluate adherence to immunization in a cohort of CKD patients in transplant waiting list and their renal replacement therapy clinics.

METHODS

CKD patients older than 18 years old, receiving renal replacement therapy longer than 12 months and included in kidney transplant waiting list at University of Campinas (Unicamp) were enrolled.

RESULTS

From February 2014 to December 2015, 105 patients fulfilled the inclusion criteria. Complete hepatitis B vaccination was observed in 73% and influenza vaccine in 67%. None of the other vaccine protocols reached 50% of coverage. Patients receiving immunization at primary health units presented higher coverage for diphtheria, tetanus (dT), measles, mumps, rubella (MMR), and hepatitis B vaccines, while patients immunized at renal replacement therapy clinics showed higher prevalence of pneumococcus (pneumo23).

CONCLUSION

The low rates of immunization could reflect the RRT's clinics knowledge about the vaccines guidelines and its application on daily care. We suggest an integration between transplant center and RRT clinics, through lectures, periodic checking of vaccination cards, and easy to follow guidelines in order to provide a better vaccine coverage and to obtain higher immunization rates.

Clinical Features of Kidney Transplant Recipients Admitted to the Intensive Care Unit

INTRODUCTION

There is a paucity of data regarding the complications in kidney transplant patients who may require intensive care unit (ICU) management, despite being the most common solid organ transplant worldwide.

OBJECTIVE

To identify the main reasons for ICU admission and to determine the factors associated with hospital mortality in kidney transplant recipients.

DESIGN

This single-center retrospective cohort study was conducted between September 2013 and June 2014, including all consecutive kidney transplant patients requiring ICU admission. We collected data on patient demographics, transplant characteristics, clinical data, and prognostic scores. The independent determinants of hospital mortality were identified by multiple logistic regression analysis. We also assessed the performance of Simplified Acute Physiology Score 3 (SAPS 3) and Acute Physiology and Chronic Health Evaluation II (APACHE II) scores.

RESULTS

We analyzed data from 413 patients, the majority of whom were admitted late after renal transplantation (1169 days; 63-3003 days). The main reason for admission was sepsis (33.2%), followed by cardiovascular disease (16%). Age (odds ratio [OR] 1.05, confidence interval [CI], 1.01-1.09), SAPS 3 score (OR 1.04, CI, 1.01-1.08), the need for mechanical ventilation (OR 26.47, CI, 10.30-68.08), and vasopressor use (OR 3.34, CI, 1.37-8.13) were independently associated with hospital mortality. The performance of SAPS 3 and APACHE II scores was poor in this population and overestimated the mortality rates.

CONCLUSION

Sepsis was the main reason for ICU admission in kidney transplant recipients, followed by cardiovascular disease. Age and disease severity were associated with hospital mortality.