Asymptomatic cytomegalovirus infection is associated with increased risk of new-onset diabetes mellitus and impaired insulin release after renal transplantation

An update review of post-transplant diabetes mellitus: Concept, risk factors, clinical implications and management

OBJECTIVE

Kidney transplantation is the gold standard therapeutic alternative for patients with end-stage renal disease; nevertheless, it is not without potential complications leading to considerable morbidity and mortality such as post-transplant diabetes mellitus (PTDM). This narrative review aims to comprehensively evaluate PTDM in terms of its diagnostic approach, underlying pathophysiological pathways, epidemiological data, and management strategies.

METHODS

Articles were retrieved from electronic databases using predefined search terms. Inclusion criteria encompassed studies investigating PTDM diagnosis, pathophysiology, epidemiology, and management strategies.

RESULTS

PTDM emerges as a significant complication following kidney transplantation, influenced by various pathophysiological factors including peripheral insulin resistance, immunosuppressive medications, infections, and proinflammatory pathways. Despite discrepancies in prevalence estimates, PTDM poses substantial challenges to transplant. Diagnostic approaches, including traditional criteria such as fasting plasma glucose (FPG) and HbA1c, are limited in their ability to capture early PTDM manifestations. Oral glucose tolerance test (OGTT) emerges as a valuable tool, particularly in the early post-transplant period. Management strategies for PTDM remain unclear, within sufficient evidence from large-scale randomized clinical trials to guide optimal interventions. Nevertheless, glucose-lowering agents and life style modifications constitute primary modalities for managing hyperglycemia in transplant recipients.

DISCUSSION

The complex interplay between PTDM and the transplant process necessitates individualized diagnostic and management approaches. While early recognition and intervention are paramount, modifications to maintenance immunosuppressive regimens based solely on PTDM risk are not warranted, given the potential adverse consequences such as increased rejection risk. Further research is essential to refine management strategies and enhance outcomes for transplant recipients.

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.

Pancreatic steatosis is an independent risk factor for post-transplant diabetes mellitus in kidney transplant patients

BACKGROUND AND AIM

Post-transplant diabetes mellitus (PTDM) is associated with an increased risk of post-transplant cardiovascular diseases, and several risk factors of PTDM have been shown in the literature. Yet, the relationship between hepatic and pancreatic steatosis with post-transplant diabetes mellitus remains vague. We aimed to evaluate pancreatic steatosis, a novel component of metabolic syndrome, and hepatic steatosis association with post-transplant diabetes mellitus in a single-center retrospective cohort study conducted on kidney transplant recipients.

METHOD

We have performed a single-center retrospective cohort study involving all kidney transplant recipients. We have utilized pretransplant Fibrosis-4, nonalcoholic fatty liver disease fibrosis score, and abdominal computed tomography for the assessment of visceral steatosis status.

RESULTS

We have included 373 kidney transplant recipients with a mean follow-up period of 32 months in our final analysis. Post-transplant diabetes mellitus risk is associated with older age (p < .001), higher body-mass index (p < .001), nonalcoholic fatty liver disease-fibrosis score (p = .002), hepatic (p < .001) or pancreatic (p < .001) steatosis on imaging and higher pre-transplant serum triglyceride (p = .003) and glucose levels (p = .001) after multivariate analysis.

CONCLUSION

Our study illustrates that recipients' pancreatic steatosis is an independent predictive factor for post-transplant diabetes mellitus including in kidney transplant patients.

Cross-seeding enables repurposing of aurein antimicrobial peptides as a promoter of human islet amyloid polypeptide (hIAPP)

Since hIAPP (human islet amyloid polypeptide) aggregation and microbial infection are recognized as significant risk factors that contribute to the pathogenesis of type II diabetes (T2D), targeting these catastrophic processes simultaneously may have a greater impact on the prevention and treatment of T2D. Different from the well-studied hIAPP inhibitors, here we propose and demonstrate a repurposing strategy for an antimicrobial peptide, aurein, which can simultaneously modulate hIAPP aggregation and inhibit microbial infection. Collective data from protein, cell, and bacteria assays revealed multiple functions of aurein including (i) promotion of hIAPP aggregation at a low molar ratio of aurein:hIAPP = 0.5 : 1-2 : 1, (ii) reduction of hIAPP-induced cytotoxicity in RIN-m5F cells, and (iii) preservation of original antimicrobial activity against E. coli., S.A., and S.E. strains in the presence of hIAPP. These functions of aurein are mainly derived from its strong binding to different hIAPP seeds through conformationally similar β-sheet association. Our study provides a promising avenue for the repurposing of antimicrobial peptides (such as aurein) as amyloid modulators for blocking at least two pathological pathways in T2D.

Cytomegalovirus High-risk Kidney Transplant Recipients Show No Difference in Long-term Outcomes Following Preemptive Versus Prophylactic Management

BACKGROUND

Following kidney transplantation (KT), cytomegalovirus (CMV) infection remains an important challenge. Both prophylactic and preemptive antiviral protocols are used for CMV high-risk kidney recipients (donor seropositive/recipient seronegative; D+/R-). We performed a nationwide comparison of the 2 strategies in de novo D+/R- KT recipients accessing long-term outcomes.

METHODS

A nationwide retrospective study was conducted from 2007 to 2018, with follow-up until February 1, 2022. All adult D+/R- and R+ KT recipients were included. During the first 4 y, D+/R- recipients were managed preemptively, changing to 6 mo of valganciclovir prophylaxis from 2011. To adjust for the 2 time eras, de novo intermediate-risk (R+) recipients, who received preemptive CMV therapy throughout the study period, served as longitudinal controls for possible confounders.

RESULTS

A total of 2198 KT recipients (D+/R-, n = 428; R+, n = 1770) were included with a median follow-up of 9.4 (range, 3.1-15.1) y. As expected, a greater proportion experienced a CMV infection in the preemptive era compared with the prophylactic era and with a shorter time from KT to CMV infection ( P  < 0.001). However, there were no differences in long-term outcomes such as patient death (47/146 [32%] versus 57/282 [20%]; P  = 0.3), graft loss (64/146 [44%] versus 71/282 [25%]; P  = 0.5), or death censored graft loss (26/146 [18%] versus 26/282 [9%]; P  = 0.9) in the preemptive versus prophylactic era. Long-term outcomes in R+ recipients showed no signs of sequential era-related bias.

CONCLUSIONS

There were no significant differences in relevant long-term outcomes between preemptive and prophylactic CMV-preventive strategies in D+/R- kidney transplant recipients.

Association of Epstein-Barr virus, cytomegalovirus and lipocalin with periodontitis in type 2 diabetic subjects

OBJECTIVE

The current study aims to evaluate and compare the lipocalin, adiponectin and periodontal viruses in the generalized periodontitis patients with and without diabetes mellitus.

MATERIALS AND METHODS

Seventy subjects were grouped into 35 systemically healthy (GP) and 35 patients with diabetes mellitus (GP+DM). The periodontal parameters, demographic and diabetic variables were evaluated in both the groups. The subgingival tissue samples were procured from the diseased sites and were analysed for the detection of EBV, CMV, HSV and protein markers by real-time polymerase chain reaction (RT-PCR) and lipocalin and adiponectin were identified by enzyme-linked immunosorbent assay (ELISA).

RESULTS

The demographic variables such as age and BMI did not differ between the groups. PI and CAL were found to be significantly higher in GP+DM (p < 0.05). EBV (82.9%), CMV (71.4%) and protein marker: lipocalin were also found to be statistically highly significant in GP+DM and adiponectin was found to be higher in GP group and reduced in GP+DM group (p < 0.0001).

CONCLUSION

The increased prevalence of EBV and CMV and lipocalin with reduced levels of adiponectin in patients with diabetes and periodontitis which may show aggravation of the diabetic status of the periodontitis patients thereby reinforcing a strong Periodontitis-DM continuum.

Relationship between Cytomegalovirus Viremia and Long-Term Outcomes in Kidney Transplant Recipients with Different Donor Ages

OBJECTIVES

To explore the Cytomegalovirus (CMV) burden on the long-term post-transplant course in different donor ages, we evaluated the incidence and risk factors for CMV in our kidney-transplanted patients (KTs) with extensive adoption of expanded-criteria donors (ECDs).

METHODS

Retrospective evaluation of 929 consecutive first KTs (49.5% receiving an organ from a donor ≥ 60 years) performed between 01-2003 and 12-2013. Overall survival was estimated using Kaplan-Meier curves; cumulative incidence function was additionally analyzed to consider the potential role of death with a functioning graft as a competitive event with graft dysfunction and to avoid overestimation. Apart from regular DNAemia monitoring in all patients, prophylaxis was adopted in high-risk groups (D+/R- or recipients of anti-thymocyte globulin induction), with pre-emptive therapy in the remaining groups.

RESULTS

CMV incidence was 19.5% (4-34.9% according to serostatus combination: D-/R-, D-/R+, D+/R+, D+/R-). Donor and recipient age, recipient pre-transplant hypertension, DR antigen compatibility, cold ischemia time, and post-transplant early complications, including rejection, urologic and renal artery stenosis, and lower renal function and proteinuria ≥ 0.5 g/day at one year after KT were associated with CMV. CMV determined lower death-censored graft survival (DCGS) (p < 0.01), with a prominent effect in R+ (p < 0.01) and without impact in R- (p = 0.32 in D-/R- and p = 0.006 in D+/R-). Interestingly, CMV occurrence influenced DCGS only in KTs who received grafts from donors < 50 or 50-69 years old (p < 0.01), while it was not significant with older donors (p = 0.07). The analysis of the cumulative incidence of graft loss accounting for death as a competing risk confirmed all these findings. In multivariate analysis, CMV replication/disease in the first year was an independent predictor for DCGS (HR 1.73 [1.3-2.3]).

CONCLUSIONS

In a large population with extensive ECD adoption, CMV viremia in the first year demonstrates its harmful effect with an independent role for graft loss and significant impact among R+ recipients and KTs with donors < 70 years.

Longitudinal Exposure to Tacrolimus and New-Onset Diabetes Mellitus in Renal Transplant Patients

PURPOSE

Tacrolimus is an immunosuppressant widely used in transplantations requiring mandatory concentration-controlled dosing to prevent acute rejection or adverse effects, including new-onset diabetes mellitus (NODM). However, no relationship between NODM and tacrolimus exposure has been established. This study aimed to evaluate the relationship between cumulative tacrolimus exposure and NODM occurrence.

METHODS

A total of 452 kidney transplant patients were included in this study. Sixteen patients developed NODM during the first 3 months after transplant. We considered all tacrolimus concentration (C0) values collected until the diagnosis of NODM in these patients and until 3 months after transplant in the others. New tacrolimus cumulative exposure metrics were derived from the time profile of the tacrolimus morning predose concentration, C0: the percentage of C0 values > cutoff, the average of C0 values above the cutoff, and the percentage of the area under C0 versus time curve, AUCC0, above the cutoff. The cutoff chosen was 15 ng/mL, corresponding to the higher end of the therapeutic range for the early post-transplant period. The influence of these metrics on NODM and other clinical and biological characteristics was investigated using the Cox models.

RESULTS

The percentage of C0 > 15 mcg/L was statistically different between patients with and without NODM (P = 0.01). Only these tacrolimus C0-derived metrics were significantly associated with an increased risk of NODM [HR: 1.73 (1.43-2.10, P < 0.001)].

CONCLUSION

This study shows that tacrolimus concentrations >15 mcg/L affect the incidence of NODM.

Incidence of Dementia Following Hospitalization With Infection Among Adults in the Atherosclerosis Risk in Communities (ARIC) Study Cohort

Importance

Factors associated with the risk of dementia remain to be fully understood. Systemic infections are hypothesized to be such factors and may be targets for prevention and screening.

Objective

To investigate the association between hospitalization with infection and incident dementia.

Design, Setting, and Participants

Data from the community-based Atherosclerosis Risk in Communities (ARIC) study, a prospective cohort study, were used. Enrollment occurred at 4 research centers in the US, initiated in 1987 to 1989. The present study includes data up to 2019, for 32 years of follow-up. Data analysis was performed from April 2021 to June 2022.

Exposures

Hospitalizations with infections were identified via medical record review for selected International Classification of Diseases, Ninth Revision (ICD-9) and International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10) codes, from baseline until administrative censoring or dementia diagnosis. Participants were considered unexposed until first hospitalization with infection and exposed thereafter. Selected infection subtypes were also considered.

Main Outcomes and Measures

Incident dementia and time-to-event data were identified through surveillance of ICD-9 and ICD-10 hospitalization and death certificate codes, in-person assessments, and telephone interviews. A sensitivity analysis was conducted excluding cases occurring within 3 years or beyond 20 years from exposure. Data were collected before study hypothesis formulation.

Results

Of the 15 792 ARIC study participants, an analytical cohort of 15 688 participants who were dementia free at baseline and of Black or White race were selected (8658 female [55.2%]; 4210 Black [26.8%]; mean [SD] baseline age, 54.7 [5.8] years). Hospitalization with infection occurred among 5999 participants (38.2%). Dementia was ascertained in 2975 participants (19.0%), at a median (IQR) of 25.1 (22.2-29.1) years after baseline. Dementia rates were 23.6 events per 1000 person-years (95% CI, 22.3-25.0 events per 1000 person-years) among the exposed and 5.7 events per 1000 person-years (95% CI, 5.4-6.0 events per 1000 person-years) among the unexposed. Patients hospitalized with infection were 2.02 (95% CI, 1.88-2.18; P < .001) and 1.70 (95% CI, 1.55-1.86; P < .001) times more likely to experience incident dementia according to unadjusted and fully adjusted Cox proportional hazards models compared with individuals who were unexposed. When excluding individuals who developed dementia less than 3 years or more than 20 years from baseline or the infection event, the adjusted hazard ratio was 5.77 (95% CI, 4.92-6.76; P < .001). Rates of dementia were significantly higher among those hospitalized with respiratory, urinary tract, skin, blood and circulatory system, or hospital acquired infections. Multiplicative and additive interactions were observed by age and APOE-ε genotype.

Conclusions and Relevance

Higher rates of dementia were observed among participants who experienced hospitalization with infection. These findings support the hypothesis that infections are factors associated with higher risk of dementias.

Kidney transplant from hepatitis C viremic donors into aviremic recipients and risk for post-transplant BK and CMV infection

BACKGROUND

kidney transplantation from HCV-viremic donors to uninfected recipients is associated with excellent short-term outcomes. However, HCV viremia might be associated with an increased risk for post-transplant viral complications.

METHODS

We designed a retrospective study of HCV-negative kidney-only transplant recipients between 2018 and 2020. Recipients were grouped into group 1; HCV-negative donors, and group 2; HCV-viremic donors. Patients were matched 1:1 using propensity score. Primary objectives were to compare the incidence of CMV viremia ≥ 200 ml/IU, and BK viremia ≥1000 copies/ml between the groups. Secondary outcomes included group comparison of CMV disease, BK viremia ≥10,000 copies/ml, and one year patient and allograft survival.

RESULTS

The study included 634 patients in group 1, and 71 patients in group 2. 65 pairs of patients were matched. Incidence of CMV viremia (33.3% vs 40.0%, p = 0.4675), and BK viremia (15.9% vs 27.7%, P = 0.1353) did not differ significantly between groups in the matched cohort. Incidence of CMV disease (81.0% Vs 76.9%; p = 1.000), and BK viremia ≥10,000 copies/ml (9.5% vs 16.9%, p = 0.2987) were comparable between groups. There was no difference in the one-year patient or allograft survival between groups.

CONCLUSION

kidney transplant from HCV-viremic donors is not associated with increased risk for BK or CMV viremia. This article is protected by copyright. All rights reserved.

Nonallograft Complications of Lung Transplantation

Long-term exposure to immunosuppressive therapy may exacerbate pre-existing medical comorbidities or result in the development of new chronic medical conditions after lung transplantation. This article focuses on common nonallograft complications with the highest impact on short- and long-term outcomes after transplantation. These include diabetes mellitus, hypertension, dyslipidemia, kidney disease (acute and chronic), and malignancy. We discuss evidence-based strategies for the prevention, diagnosis, and management of these nonallograft complications in this article.

Management of Diabetes in Candidates for Liver Transplantation and in Transplant Recipients

Diabetes is common in patients waitlisted for liver transplantation because of end-stage liver disease or hepatocellular cancer as well as in posttransplant phase (posttransplantation diabetes mellitus). In both conditions, the presence of diabetes severely affects disease burden and long-term clinical outcomes; careful monitoring and appropriate treatment are pivotal to reduce cardiovascular events and graft and recipients' death. We thoroughly reviewed the epidemiology of diabetes in the transplant setting and the different therapeutic options, from lifestyle intervention to antidiabetic drug use-including the most recent drug classes available-and to the inclusion of bariatric surgery in the treatment cascade. In waitlisted patients, the old paradigm that insulin should be the treatment of choice in the presence of severe liver dysfunction is no longer valid; novel antidiabetic agents may provide adequate glucose control without the risk of hypoglycemia, also offering cardiovascular protection. The same evidence applies to the posttransplant phase, where oral or injectable noninsulin agents should be considered to treat patients to target, limiting the impact of disease on daily living, without interaction with immunosuppressive regimens. The increasing prevalence of liver disease of metabolic origin (nonalcoholic fatty liver) among liver transplant candidates, also having a higher risk of noncirrhotic hepatocellular cancer, is likely to accelerate the acceptance of new drugs and invasive procedures, as suggested by international guidelines. Intensive lifestyle intervention programs remain however mandatory, both before and after transplantation. Achievement of adequate control is mandatory to increase candidacy, to prevent delisting, and to improve long-term outcomes.

Predictors of New-onset Diabetes After Kidney Transplantation During 2019-nCoV Pandemic: A Unison of Frequentist Inference and Narrow AI

BACKGROUND: New-onset diabetes after kidney transplant (NODAT) is a severe metabolic complication that frequently occurs in recipients following transplantation. AIM: The study aims to verify NODAT, compare cases and non-cases of this entity, and explore potential predictors in recipients within 1 year following kidney transplantation. METHODS: The research is a retrospective study of 90 renal transplant recipients (n = 90). Demographic factors and clinical aspects were analyzed using non-Bayesian statistics and machine learning (ML). The clinical aspects included the glycated hemoglobin (HbA1c) level, associated viral infections (hepatitis B virus [HBV], hepatitis C virus [HCV], and cytomegalovirus [CMV]), prior kidney transplant, hemodialysis status, body mass index (BMI) at transplant time, and 3 months later, primary causes of renal failure, and post-transplant therapeutics. All individuals were on cyclosporine and prednisolone treatment. RESULTS: The mean age was 39 (±1.5) years; recipients included 27 females (30%) and 63 males (70%). Donor type was live related (16, 17.8%) or live unrelated (74, 82.2%); 27 recipients (30%) had O+ blood group, while 70% belonged to other groups. Thirteen recipients (14.4%) were not on dialysis. Only 32 individuals (35.6%) developed NODAT. Concerning virology, confirmed by real-time polymerase chain reaction before transplantation, 19 recipients (21.1%) were CMV positive, 9 (10%) were HCV positive, and 2 (2.2%) had HBV. CONCLUSIONS: In reconciliation with frequentist statistics, the dual ML model validated several predictors that either negatively (protective) or positively (harmful) influenced HbA1c level, the majority of which were significant at 95% confidence interval. Individuals who are HCV and CMV positive are predicted to develop NODAT. Further, older individuals, with blood group O+ve, prior history of hemodialysis, a relatively high BMI before the transplant, and receiving higher doses of prednisolone following the transplant are more likely to develop NODAT. The current study represents the first research from Iraq to explore NODAT predictors among kidney transplant recipients using frequentist statistics and artificial intelligence models.

Cytomegalovirus Exposure and the Risk of Overall Infection After Kidney Transplantation: A Cohort Study on the Indirect Effects Attributable to Viral Replication

Previous reports hypothesized that cytomegalovirus (CMV) may predispose to non-CMV infection after kidney transplantation (KT). We analysed the incidence of non-CMV infection (overall, bacterial and opportunistic) in 291 KT recipients according to the previous development of any level or high-level (≥1,000 IU/ml) CMV viremia. Exposure to CMV replication was assessed throughout fixed intervals covering first the 30, 90, 180 and 360 post-transplant days (cumulative exposure) and non-overlapping preceding periods (recent exposure). Adjusted Cox models were constructed for each landmark analysis. Overall, 67.7 and 50.5% patients experienced non-CMV and CMV infection, respectively. Patients with cumulative CMV exposure had higher incidence of non-CMV infection beyond days 30 (p-value = 0.002) and 90 (p-value = 0.068), although these associations did not remain after multivariable adjustment. No significant associations were observed for the remaining landmark models (including those based on high-level viremia or recent CMV exposure), or when bacterial and opportunistic infection were separately analysed. There were no differences in viral kinetics (peak CMV viremia and area under curve of CMV viral load) either. Our findings do not support the existence of an independent association between previous CMV exposure and the overall risk of post-transplant infection, although results might be affected by power limitations.

Posttransplant Diabetes Mellitus and Immunosuppression Selection in Older and Obese Kidney Recipients

Rationale & Objective

Posttransplant diabetes mellitus (DM) after kidney transplantation increases morbidity and mortality, particularly in older and obese recipients. We aimed to examine the impact of immunosuppression selection on the risk of posttransplant DM among both older and obese kidney transplant recipients.

Study Design

Retrospective database study.

Setting & Participants

Kidney-only transplant recipients aged ≥18 years from 2005 to 2016 in the United States from US Renal Data System records, which integrate Organ Procurement and Transplantation Network/United Network for Organ Sharing records with Medicare billing claims.

Exposures

Various immunosuppression regimens in the first 3 months after transplant.

Outcomes

Development of DM >3 months-to-1 year posttransplant.

Analytical Approach

We used multivariable Cox regression to compare the incidence of posttransplant DM by immunosuppression regimen with the reference regimen of thymoglobulin (TMG) or alemtuzumab (ALEM) with tacrolimus + mycophenolic acid + prednisone using inverse propensity weighting.

Results

12.7% of kidney transplant recipients developed posttransplant DM with higher incidences in older (≥55 years vs <55 years: 16.7% vs 10.1%) and obese (body mass index [BMI] ≥ 30 kg/m² vs BMI < 30 kg/m²: 17.1% vs 10.9%) patients. The incidence of posttransplant DM was lower with steroid avoidance [TMG/ALEM + no prednisone (8.4%) and IL2rAb + no prednisone (9.7%)] than TMG/ALEM with triple therapy (13.1%). After adjustment for donor and recipient characteristics, TMG/ALEM with steroid avoidance was beneficial for all groups [age < 55 years: adjusted HR (aHR), 0.63 (95% confidence interval [CI], 0.54-0.72); age ≥ 55 years: aHR, 0.69 (95% CI, 0.60-0.79); BMI < 30 kg/m²: aHR, 0.69 (95% CI, 0.60-0.78); BMI ≥ 30 kg/m²: aHR, 0.67 (95% CI, 0.57-0.79)]. However, IL2rAb with steroid avoidance was beneficial only for older patients (aHR, 0.76; 95% CI, 0.58-0.99) and for those with BMI < 30 kg/m² (aHR, 0.63; 95% CI, 0.46-0.87).

Limitations

Retrospective study and lacked data on immunosuppression levels.

Conclusions

The beneficial impact of steroid avoidance using tacrolimus on posttransplant DM appears to differ by patient age and induction regimen.

Obesity and Post-Transplant Diabetes Mellitus in Kidney Transplantation

Worldwide, the prevalence obesity, diabetes, and chronic kidney disease is increasing apace. The relationship between obesity and chronic kidney disease is multidimensional, especially when diabetes is also considered. The optimal treatment of patients with chronic kidney disease includes the need to consider weight loss as part of the treatment. The exact relationship between obesity and kidney function before and after transplantation is not as clear as previously imagined. Historically, patients with obesity had worse outcomes following kidney transplantation and weight loss before surgery was encouraged. However, recent studies have found less of a correlation between obesity and transplant outcomes. Transplantation itself is also a risk factor for developing diabetes, a condition known as post-transplant diabetes mellitus, and is related to the use of immunosuppressive medications and weight gain following transplantation. Newer classes of anti-diabetic medications, namely SGLT-2 inhibitors and GLP-1 agonists, are increasingly being recognized, not only for their ability to control diabetes, but also for their cardio and renoprotective effects. This article reviews the current state of knowledge on the management of obesity and post-transplant diabetes mellitus for kidney transplant patients.

Safety and Efficacy of Long-Term Administration of Dipeptidyl peptidase IV Inhibitors in Patients With New Onset Diabetes After Kidney Transplant

OBJECTIVES

The appearance of new onset diabetes is common after kidney transplant. Treatment options are limited because of renal function-related contraindications, interactions with immunosuppressive drugs, and side effects. We investigated the long-term safety and efficacy of dipeptidyl peptidase IV inhibitors in renal transplant recipients with new onset diabetes.

MATERIALS AND METHODS

We treated 12 patients with dipeptidyl peptidase IV inhibitors, and 5 patients received insulin monotherapy as initial treatment of new onset diabetes after kidney transplant. All patients were followed for 12 months after diagnosis. Glycosylated hemoglobin A1c, estimated glomerular filtration rate (Chronic Kidney Disease Epidemiology Collaboration equation), plasma immunosuppressive trough levels, serum lipids, blood pressure, and body weight were measured during outpatient visits. Effects of dipeptidyl peptidase IV inhibitors and insulin on the aforementioned parameters were measured to compare values at time of diagnosis versus mean values of the last 6 months of follow-up.

RESULTS

Patients were treated with linagliptin (4 patients), sitagliptin (4 patients), vildagliptin (2 patients), and alogliptin (2 patients). Patients had a mean age of 59.4 ± 12 years and a mean glycosylated hemoglobin A1c of 6.6% at diagnosis, which was decreased to 6.1% (P = .03) at 1 year of follow-up. Renal function remained stable, and plasma tacrolimus levels did not appear to be affected. No significant differences were shown in serum total, low-density lipoprotein, and high-density lipoprotein cholesterol levels aftertreatment. Nevertheless,triglyceride levels were significantly reduced (from 214.4 to 174.9 mg/dL; P = .0039). A decrease in body weight was also observed. Finally, patients treated with dipeptidyl peptidase V inhibitors achieved better glycosylated hemoglobin A1c levels than those treated with insulin.

CONCLUSIONS

Dipeptidyl peptidase IV inhibitors appear to be a safe, effective, and hypoglycemia-free option fortreatment of new onset diabetes in renaltransplant recipients and possibly provide better diabetes control than insulin therapy.

Current Pharmacological Intervention and Medical Management for Diabetic Kidney Transplant Recipients

Hyperglycemia after kidney transplantation is common in both diabetic and non-diabetic patients. Both pretransplant and post-transplant diabetes mellitus are associated with increased kidney allograft failure and mortality. Glucose management may be challenging for kidney transplant recipients. The pathophysiology and pattern of hyperglycemia in patients following kidney transplantation is different from those with type 2 diabetes mellitus. In patients with pre-existing and post-transplant diabetes mellitus, there is limited data on the management of hyperglycemia after kidney transplantation. The following article discusses the nomenclature and diagnosis of pre- and post-transplant diabetes mellitus, the impact of transplant-related hyperglycemia on patient and kidney allograft outcomes, risk factors and potential pathogenic mechanisms of hyperglycemia after kidney transplantation, glucose management before and after transplantation, and modalities for prevention of post-transplant diabetes mellitus.

Analysis of the frequency of single nucleotide polymorphisms in cytokine genes in patients with New Onset Diabetes After Transplant

New Onset Diabetes After Transplantation (NODAT) is a serious metabolic complication. While β-cell dysfunction is considered the main contributing factor in the development of NODAT, the precise pathogenesis is not well understood. Cytokines are thought to be involved in the inflammation of islet β-cells in diabetes; however, few studies have investigated this hypothesis in NODAT. A total of 309 kidney transplant recipients (KTRs) were included in this study. An association between kidney transplants, and the development of diabetes after transplant (NODAT) was investigated. Comparison was made between KTRs who develop diabetes (NODAT cases) or did not develop diabetes (control), using key cytokines, IL-6 G (− 174)C, macrophage mediator; IL-4 C (− 490)T, T helper (Th)-2 cytokine profile initiator; Th-1 cytokine profile initiator interferon-γ T (+ 874) A gene and TGF β1 C (+ 869) T gene polymorphisms were investigated. The genes were amplified using well-established polymerase chain reaction (PCR) techniques in our laboratory. Compared to the AA and AT genotypes of interferon gamma (IFNG), there was a strong association between the TT genotype of IFNG and NODAT kidney transplant recipients (KTRs) versus non-NODAT KTRs (p = 0.005). The AA genotype of IFNG was found to be predominant in the control group (p = 0.004). Also, significant variations of IL6 G (− 174) C, IL-4 C (− 590) T, interferon-γ T (+ 874) A gene and transforming growth factor β1 C (+ 869) T may contribute to NODAT. Our data is consistent with theTh-1/T-reg pathway of immunity. Further larger pan Arab studies are required to confirm our findings.

Does reactivation of cytomegalovirus contribute to severe COVID-19 disease?

The majority of people infected with SARS-CoV-2 are asymptomatic or have mild to moderate symptoms. However, for unknown reasons, about 15 % have severe pneumonia requiring hospital care and oxygen support, and about 5 % develop acute respiratory distress syndrome, septic shock, and multiorgan failure that result in a high mortality rate. The risk of severe COVID-19 is highest among those who are over 70 years of age. Why severe COVID-19 develops in some people but not others is not understood. Could some cases involve reactivation of latent cytomegalovirus (CMV)?

Peptide Vaccination against Cytomegalovirus Induces Specific T Cell Response in Responses in CMV Seronegative End-Stage Renal Disease Patients

Introduction: Cytomegalovirus (CMV) reactivation occurs in seronegative patients after solid organ transplantation (SOT) particularly from seropositive donors and can be lethal. Generation of CMV-specific T cells helps to prevent CMV reactivation. Therefore, we initiated a clinical phase I CMVpp65 peptide vaccination trial for seronegative end-stage renal disease patients waiting for kidney transplantation. Methods: The highly immunogenic nonamer peptide NLVPMVATV derived from CMV phosphoprotein 65(CMVpp65) in a water-in-oil emulsion (Montanide™) plus imiquimod (Aldara™) as an adjuvant was administered subcutaneously four times biweekly. Clinical course as well as immunological responses were monitored using IFN-γ ELISpot assays and flow cytometry for CMV-specific CD8⁺ T cells. Results: Peptide vaccination was well tolerated, and no drug-related serious adverse events were detected except for Grade I–II local skin reactions. Five of the 10 patients (50%) mounted any immune response (responders) and 40% of the patients presented CMV-specific CD8⁺ T cell responses elicited by these prophylactic vaccinations. No responders experienced CMV reactivation in the 18 months post-transplantation, while all non-responders reactivated. Conclusion: CMVpp65 peptide vaccination was safe, well tolerated, and clinically encouraging in seronegative end-stage renal disease patients waiting for kidney transplantation. Further studies with larger patient cohorts are planned.

Population Pharmacokinetics and Bayesian Estimation of the Area Under the Concentration-Time Curve for Ganciclovir in Adult Chinese Renal Allograft Recipients After Valganciclovir Administration

Valganciclovir (VGCV) is the prodrug of ganciclovir (GCV). The objective of this study was to establish a population pharmacokinetic model (PPK) of GCV to investigate the PK characteristics of GCV after administration of VGCV in adult Chinese renal allograft recipients. Seventy Chinese renal allograft recipients were given 450 mg (n = 41) or 900 mg (n = 29) VGCV daily. Blood samples were drawn 0-24 hours after 5 days' therapy, and GCV plasma levels were determined. The PPK model was constructed using nonlinear mixed-effects modeling, and the Bayesian estimation of AUC_0-24h was constructed for an individual patient based on limited plasma samples. The PK of GCV was best described by a 2-compartment model with a first-order absorption process. The CL/F, V₂ /F, Q/F, V₃ /F, K_a , and lag time of GCV were 15.8 ± 0.71 L/h, 10.9 ± 2.38 L, 3.98 ± 0.40 L/h, 167 ± 44.0 L, 0.23 ± 0.0078 1/h, and 0.93 ± 0.017 hours, respectively. Clearance of creatinine was found to have a significant impact on the CL/F of GCV (P < .01). Sampling strategies consisted of plasma concentrations 0 and 2 and 0, 2, and 4 hours after VGCV administration were shown to be suitable for the estimation of the GCV AUC_0-24h . The PPK model was acceptable and can describe the PK of GCV in Chinese renal transplant patients administered VGCV. The AUC_0-24h of GCV in Chinese renal transplant patients can be calculated by a limited sampling strategy method.

Prevalence and Risk Factors of New-Onset Diabetes After Transplantation (NODAT)

Background

New-onset diabetes after transplantation (NODAT) is a serious complication after a solid organ transplant. NODAT occurs in 2% to 53% of all solid organ transplant recipients. The identification of high-risk patients and the implementation of measures to limit the development of NODAT can improve the long-term patient prognosis.

Material/Methods

Our study group consisted of 336 patients undergoing heart transplant. Patients with prior diabetes (60 patients) were excluded from analysis. The remaining 276 patients were divided in 2 groups: with NODAT (n=109) and without NODAT (n=167). Logistic regression analysis was used for NODAT risk factor assessment.

Results

NODAT occurred in 109 (32%) out of 336 patients without diagnosed diabetes before heart transplantation. Risk factors for post-transplant diabetes mellitus, which was shown by the analysis of the collected data, were BMI at discharge (OR=1.082, CI 1.011–1.158, p=0.0233), history of diagnosed CMV infection (OR=1.464, CI 1.068–2.007, p=0.0179), and age over 51 years (OR=1.634, CI 1.274–2.095, p=0.0001).

Conclusions

1. New-onset diabetes after transplantation (NODAT) or long-lasting hypoglycemia (over 2 years after transplantation) was diagnosed in 32% patients after heart transplantation developed. 2. The risk factors of NODAT were BMI at discharge and history of diagnosed CMV infection, and age over 51 years was an independent risk factor.

Risk Factors Related to New-Onset Diabetes after Renal Transplantation in Patients of a High Complexity University Hospital in Colombia, 20 Years of Experience

INTRODUCTION

New-onset diabetes after transplantation (NODAT) is associated with immunosuppression. Its complications can negatively influence patients' quality of life, which is why it is important to study the associated risk factors and expand the possible therapies in this particular group of patients. Materials and methods. Case-control study nested in a retrospective cohort. It included patients who received kidney transplantation at the high complexity University Hospital Fundación Valle del Lili in Cali, Colombia, between 1995 and 2014. Two controls were assigned for each case, depending on the type of donor and the date of the surgery. Information was collected from clinical records and the institutional TRENAL registry. We carried out a descriptive analysis of the selected variables and identified the risk factors with conditional logistic regression.

RESULTS

122 cases were identified to which 224 controls were assigned. The median age was 44 years (IQR: 34-55), and 54% were men. Having >50 years of age at the time of transplantation (OR: 3.18, 95% CI: 1.6-6.3, p = 0.001), body mass index >30 kg/m² (OR: 3.6, 95% CI: 1.3-9.7, p = 0.010) and being afro-descendant (OR: 2.74, 95% CI: 1.1-6.5, p = 0.023) were identified as risk factors for the development of NODAT. Pretransplant fasting plasma glucose >100 mg/dl (OR: 2.9, 95% CI: 1.4-6.4, p = 0.005) and serum triglycerides >200 mg/dl (OR: 2.5, 95% CI: 1.4-4.4, p = 0.002) were also reported as independent risk factors.

CONCLUSION

We ratify some risk factors for the development of this important disease, which include certain modifiable characteristics. Interventions aimed at changes in lifestyle could be established in a timely manner before transplant surgery.

Validation of Identified Susceptible Gene Variants for New-Onset Diabetes in Renal Transplant Recipients

Genome-wide association studies (GWAS) and candidate gene approaches have identified single nucleotide polymorphisms (SNPs) associated with new-onset diabetes after renal transplantation (NODAT). We evaluated associations between NODAT and SNPs identified in previous studies. We genotyped 1102 renal transplant recipients from the Korean Organ Transplantation Registry (KOTRY) database; 13 SNPs were assessed for associations with NODAT (occurring in 254 patients; 23.0%), within one year after transplantation. The frequency of the T allele at KCNQ1 rs2237892 was significantly lower in patients with NODAT compared to control patients (0.30 vs. 0.39; p = 8.5 × 10^-5). The T allele at rs2237892 was significantly associated with decreased risk of NODAT after adjusting for multiple variables, compared to the C allele (OR 0.63, 95% CI 0.51-0.79; p = 5.5 × 10^-5). Dominant inheritance modeling showed that CT/TT genotypes were associated with a lower risk for development of NODAT (OR 0.56, 95% CI 0.42-0.76; p = 2.0 × 10^-4) compared to the CC genotype. No other SNPs were associated with NODAT. Our study validated the protective effect of T allele at KCNQ1 rs2237892 on the development of NODAT in a large cohort of renal transplant recipients. Our findings on susceptibility variants might be a useful tool to predict NODAT development after renal transplantation.

Risk factors for cytomegalovirus infection in patients with antineutrophil cytoplasmic antibody-associated vasculitis

Aims

Cytomegalovirus (CMV) infection under immunosuppression sometimes causes death. This study aimed to elucidate risk factors for CMV infection in patients with antineutrophil cytoplasmic antibody-associated vasculitis (AAV).

Methods

Patients with AAV who underwent remission induction treatment at Okayama University Hospital between 2006 and 2016 were retrospectively analyzed. The primary outcome was the development of CMV infection within 3 months.

Results

Of the 111 patients, 13 (11.7%) patients developed CMV infection. Patients with CMV infection were older (p = 0.030) and had a higher body mass index (p = 0.029) in comparison to those without CMV infection. A higher proportion had a severe form (p = 0.001) and granulomatosis with polyangiitis (GPA) (p = 0.001), as well as a higher Birmingham Vasculitis Activity Score (p = 0.018) and C-reactive protein (p = 0.018) levels at baseline. Using logistic regression analysis, severe form and GPA were independent risk factors (odds ratio [OR] = 9.68, 95% confidence interval [CI] = 1.92–60.23, and OR = 7.46, 95% CI = 1.46–47.60, respectively). In addition, patients with CMV infection were more likely than those without infection to be glucocorticoid-related diabetes mellitus (p = 0.025).

Conclusion

Our study highlights disease severity and subgroups of AAV as risk factors for CMV infection.

Role of sex in post-transplant diabetes mellitus development: Are men and women equal?

INTRODUCTION

Sex differences are defined as biology-linked differences between women and men that occur through the sex chromosomes and their effects on organ systems.

MATERIAL AND METHODS

The objective of this prospective study was to determine risk factors for post-transplant diabetes mellitus (PTDM) in men and women.

RESULTS

A total of 417 patients (271 men and 146 women) were included in the monitored group. Age at the time of kidney transplantation (KT) >60 years and hypovitaminosis D at the time of KT (<20 μg/l) were identified as independent risk factors for PTDM in both men and women. It was further confirmed as an independent risk factor for men a waist circumference at the time of KT >94 cm, C-peptide at the time of KT >5 ng/ml, HOMA-IR >2 and triacylglycerols at the time of KT >1.7 mmol/l. In case of women, the dominant factor was BMI at the time of KT >30 kg/m2 and menopause at the time of KT. A significant decrease in C-peptide was recorded in women with PTDM.

CONCLUSION

It was confirmed that there are gender differences with regard to the development of PTDM after KT. Women show pancreas β cell dysfunction, whereas insulin resistance and metabolic syndrome are dominant in men.

Post-transplant diabetes mellitus in patients with solid organ transplants

Solid organ transplantation (SOT) is a life-saving procedure and an established treatment for patients with end-stage organ failure. However, transplantation is also accompanied by associated cardiovascular risk factors, of which post-transplant diabetes mellitus (PTDM) is one of the most important. PTDM develops in 10-20% of patients with kidney transplants and in 20-40% of patients who have undergone other SOT. PTDM increases mortality, which is best documented in patients who have received kidney and heart transplants. PTDM results from predisposing factors (similar to type 2 diabetes mellitus) but also as a result of specific post-transplant risk factors. Although PTDM has many characteristics in common with type 2 diabetes mellitus, the prevention and treatment of the two disorders are often different. Over the past 20 years, the lifespan of patients who have undergone SOT has increased, and PTDM becomes more common over the lifespan of these patients. Accordingly, PTDM becomes an important condition not only to be aware of but also to treat. This Review presents the current knowledge on PTDM in patients receiving kidney, heart, liver and lung transplants. This information is not only for transplant health providers but also for endocrinologists and others who will meet these patients in their clinics.

Non-immunological complications following kidney transplantation

Kidney transplantation (KT) is the most effective way to decrease the high morbidity and mortality of patients with end-stage renal disease. However, KT does not completely reverse the damage done by years of decreased kidney function and dialysis. Furthermore, new offending agents (in particular, immunosuppression) added in the post-transplant period increase the risk of complications. Cardiovascular (CV) disease, the leading cause of death in KT recipients, warrants pre-transplant screening based on risk factors. Nevertheless, the screening methods currently used have many shortcomings and a perfect screening modality does not exist. Risk factor modification in the pre- and post-transplant periods is of paramount importance to decrease the rate of CV complications post-transplant, either by lifestyle modification (for example, diet, exercise, and smoking cessation) or by pharmacological means (for example, statins, anti-hyperglycemics, and so on). Post-transplantation diabetes mellitus (PTDM) is a major contributor to mortality in this patient population. Although tacrolimus is a major contributor to PTDM development, changes in immunosuppression are limited by the higher risk of rejection with other agents. Immunosuppression has also been implicated in higher risk of malignancy; therefore, proper cancer screening is needed. Cancer immunotherapy is drastically changing the way certain types of cancer are treated in the general population; however, its use post-transplant is limited by the risk of allograft rejection. As expected, higher risk of infections is also encountered in transplant recipients. When caring for KT recipients, special attention is needed in screening methods, preventive measures, and treatment of infection with BK virus and cytomegalovirus. Hepatitis C virus infection is common in transplant candidates and in the deceased donor pool; however, newly developed direct-acting antivirals have been proven safe and effective in the pre- and post-transplant periods. The most important and recent developments on complications following KT are reviewed in this article.

Valganciclovir Prophylaxis Versus Preemptive Therapy in Cytomegalovirus-Positive Renal Allograft Recipients: Long-term Results After 7 Years of a Randomized Clinical Trial

BACKGROUND

The VIPP study compared valganciclovir prophylaxis with preemptive treatment regarding efficacy, safety, and long-term graft outcome in cytomegalovirus (CMV)-positive (R+) renal transplant recipients.

METHODS

Multicenter, open-label, randomized clinical study with a 12-month study phase and a follow-up of up to 84 months. Patients in the prophylaxis group received 2 × 450 mg/d oral valganciclovir for 100 days adjusted to renal function. Preemptive treatment with 2 × 900 mg/d valganciclovir was initiated at a viral load of 400 CMV copies/mL or greater (polymerase chain reaction) and maintained over ≥14 days, followed by secondary prophylaxis. Patients were stratified by donor CMV IgG serostatus (donor CMV IgG positive [D+]/R+, donor CMV IgG negative [D-]/R+).

RESULTS

The 12-month results were reported previously (Witzke et al Transplantation 2012). The intent-to-treat/safety population comprised 148 patients in the prophylaxis (61.5% D+/R+) and 151 patients in the preemptive group (52.3% D+/R+). Overall, 47% patients completed the follow-up. Significantly fewer patients in the prophylaxis compared with preemptive group experienced a CMV infection or disease up to month 84 (11.5%; 95% confidence interval [95% CI], 6.8-17.8%] vs 39.7%; 95% CI, 31.9-48.0%; P < 0.0001 and 4.7%; 95% CI, 1.9-9.5% vs 15.9%; 95% CI, 10.5-22.7%; P = 0.002). Incidences of graft loss (7.4% vs 8.6%), death (9.5% vs 11.3%), rejection (29.1% vs 28.5%), and renal function (estimated glomerular filtration rate [mean ± SD]: 58.2 ± 26.3 vs 59.9 ± 25.7 mL/min per 1.73 m) were not significantly different between prophylaxis and preemptive treatment. Tolerability was comparable between groups.

CONCLUSIONS

Prophylaxis was more effective than the preemptive approach, applying a low-intense surveillance protocol in preventing CMV infection and disease in intermediate-risk patients. Both strategies were similarly effective in preventing graft loss and death under the conditions of this long-term trial with a threshold of 400 copies/mL for initiation of anti-CMV treatment.

Immunogenetics of new onset diabetes after transplantation in Kuwait

Introduction and aim: New onset diabetes after transplantation (NODAT) is a serious metabolic complication following kidney transplantation. Although beta-cell dysfunction is considered the main contributing factor in the development of this complication, its exact etiology is yet to be identified. We aimed to investigate NODAT among kidney transplant cohort in Kuwait with special stress on correlation between its risk factors and interferon gamma genotyping. Materials and methods: We surveyed 309 kidney transplant recipients from Hamed Al Essa Transplantation Centre, Kuwait. The participants were categorized into cohorts according to the development of NODAT diagnosed based on the American Diabetes Association guidelines. Statistical analyses were performed using SPSS software. We genotyped interferon gamma as the leading immunosignature for T lymphocyte. Results: No relationship between ethnicity and the development of NODAT was identified. However, there was a significant difference in age between cohorts. Younger patients demonstrated a lower rate of NODAT while, NODAT reached its maximum in 40-60-year age group. IFNG TT genotype was significantly associated with NODAT (p=0.005), while IFNG AA was considerably higher in the non-NODAT group. Conclusion: Beside the conventional contributing factors of NODAT, our results might represent a suitable platform for a larger cytokine and chemokine spectrum genotyping.

Development of a Predictive Model Using Endoscopic Features for Gastric Cytomegalovirus Infection in Renal Transplant Patients

BACKGROUND

Cytomegalovirus (CMV) is a common viral pathogen in transplant patients which often targets the stomach. However, the endoscopic characteristics of gastric CMV infection are not well established. We aimed to develop a predictive model using endoscopic findings for gastric CMV infection in renal transplant patients.

METHODS

A retrospective study of 287 kidney transplant recipients who underwent endoscopy with biopsy for suspected CMV infection from January 2006 to November 2015 at a tertiary referral hospital was performed. CMV infection was defined based on inclusion bodies in hematoxylin and eosin and immunohistochemical staining. Endoscopic and clinical parameters related to gastric CMV infection were selected by univariate analyses. Multivariate logistic regression was used to create a predictive model from β-coefficients.

RESULTS

CMV was present in 107 (37.7%) of the 287 patients. Multivariate analysis found age (odds ratio [OR], 0.964; 95% confidence interval [CI], 0.938-0.99; P = 0.008), erosions with surface exudate (OR, 5.34; 95% CI, 2.687-10.612; P < 0.001), raised shape of erosions (OR, 3.957; 95% CI, 1.937-8.083; P < 0.001), and antral location of ulcers (OR, 15.018; 95% CI, 5.728-39.371; P < 0.001) as independent predictive factors for gastric CMV infection. Using the predictive model created from this analysis, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 71.03%, 85.56%, 74.51%, 83.24%, and 80.14%, respectively. The area under the receiver operating characteristic curve of this model for detecting CMV infection was 0.850 (95% CI, 0.803-0.889; P < 0.001).

CONCLUSIONS

The predictive model with typical endoscopic findings may be useful for detecting gastric CMV infection in renal transplant patients.

Association between cytomegalovirus seropositivity and Type 2 diabetes is explained by age and other demographic characteristics: the National Health and Nutrition Examination Survey

AIMS

To assess the association between cytomegalovirus and Type 2 diabetes among 6664 participants from the National Health and Nutrition Examination Survey.

METHODS

We used existing data from adults aged 20-49 years who participated in the National Health and Nutrition Examination Survey from 1999 to 2004. Cytomegalovirus status was determined using cytomegalovirus-specific immunoglobulin G antibodies. Prevalent Type 2 diabetes was assessed through self-report or a plasma fasting glucose of ≥7 mmol/l. Logistic regression models were used to evaluate the association between Type 2 diabetes and cytomegalovirus seropositivity after adjustment for age, gender, race/ethnicity, smoking status, education, BMI and physical activity.

RESULTS

In a univariate model, the crude odds of Type 2 diabetes were 47% higher in those who were cytomegalovirus-seropositive vs cytomegalovirus-seronegative. The association was attenuated and no longer significant after adjustment for age and other covariates: the odds ratio for diabetes was 1.09 (95% CI 0.71 to 1.66) for cytomegalovirus-seropositive vs -seronegative individuals.

CONCLUSIONS

Our study suggests that the association between cytomegalovirus and Type 2 diabetes is explained by age and other risk factors for diabetes.

New-onset diabetes after kidney transplantation: can the risk be modified by choosing immunosuppression regimen based on pretransplant viral serology?

Background

This study aimed to analyze adult kidney transplant recipients (KTRs) for the risk of new-onset diabetes after transplantation (NODAT) associated with viral serologies and immunosuppression regimens [tacrolimus (Tac) + mycophenolate (MPA), cyclosporine (CSA) + MPA, sirolimus (SRL) + MPA, SRL + CSA or SRL +Tac].

Methods

Cox regression models were used to examine the risk of NODAT in the first posttransplant year associated with: (i) CSA + MPA, SRL + MPA, SRL + MPA or SRL + Tac versus reference, Tac + MPA; (ii) pretransplant viral serology [+ or -; hepatitis B core (HBc), hepatitis C (HCV), cytomegalovirus (CMV) or Epstein Barr Virus (EBV)]; and (iii) interactions between immunosuppression regimens and the viral serology found significant in the main analysis.

Results

Adult KTRs (n = 97 644) from January 1995 through September 2015 were studied. HCV+ [hazard ratio (HR) 1.50, 95% confidence interval (CI) 1.31-1.68] or CMV+ (HR 1.12, 95% CI 1.06-1.19) serology was a risk factor and HBc+ (HR 1.04, 95% CI 0.95-1.15) or EBV+ (HR 1.06, 95% CI 0.97-1.15) serology was not a risk factor for NODAT. Regardless of associated HCV or CMV serology, risk of NODAT relative to the reference regimen (Tac + MPA) was lower with CSA + MPA [HCV-: HR 0.74, 95% CI 0.65-0.85; HCV+: HR 0.47, 95% CI 0.28-0.78; CMV-: CSA + MPA HR 0.68, 95% CI 0.54-0.86; CMV+: (CSA + MPA) HR 0.73, 95% CI 0.63-0.85] and similar with SRL + CSA or SRL + MPA. In KTRs with HCV- or CMV+ serology, SRL + Tac was associated with a higher risk of NODAT relative to reference [HCV- (HR 1.43, 95% CI 1.17-1.74) and CMV+ (HR 1.44, 95% CI 1.14-1.81), respectively]. The risk for NODAT-free graft loss was lower with Tac + MPA than the other regimens.

Conclusions

Tailoring immunosuppression regimen based on HCV or CMV serology may modify the risk of developing NODAT in KTRs.

Less renal allograft fibrosis with valganciclovir prophylaxis for cytomegalovirus compared to high-dose valacyclovir: a parallel group, open-label, randomized controlled trial

BACKGROUND

Cytomegalovirus (CMV) prophylaxis may prevent CMV indirect effects in renal transplant recipients. This study aimed to compare the efficacy of valganciclovir and valacyclovir prophylaxis for CMV after renal transplantation with the focus on chronic histologic damage within the graft.

METHODS

From November 2007 through April 2012, adult renal transplant recipients were randomized, in an open-label, single-center study, at a 1:1 ratio to 3-month prophylaxis with valganciclovir (n = 60) or valacyclovir (n = 59). The primary endpoint was moderate-to-severe interstitial fibrosis and tubular atrophy assessed by protocol biopsy at 3 years evaluated by a single pathologist blinded to the study group. The analysis was conducted in an intention-to-treat population.

RESULTS

Among the 101 patients who had a protocol biopsy specimen available, the risk of moderate-to-severe interstitial fibrosis and tubular atrophy was significantly lower in those treated with valganciclovir (22% versus 34%; adjusted odds ratio, 0.31; 95% confidence interval, 0.11-0.90; P = 0.032 by multivariate logistic regression). The incidence of CMV disease (9% versus 2%; P = 0.115) and CMV DNAemia (36% versus 42%; P = 0.361) were not different at 3 years.

CONCLUSIONS

Valganciclovir prophylaxis, as compared with valacyclovir, was associated with a reduced risk of moderate-to-severe interstitial fibrosis and tubular atrophy in patients after renal transplantation.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry ( ACTRN12610000016033 ). Registered on September 26, 2007.

New-onset diabetes after kidney transplantation: Incidence and associated factors

AIM

To determine the incidence and associated factors of new-onset diabetes after transplantation (NODAT) in a Portuguese central hospital.

METHODS

This single-center retrospective study involved consecutive adult nondiabetic transplant recipients, who had undergone kidney transplantation between January 2012 and March 2016. NODAT was diagnosed according to the criteria of the American Diabetes Association. Data were collected from an institutional database of the Nephrology and Kidney Transplantation Department (Santa Maria Hospital, Lisbon, Portugal) and augmented with data of laboratorial parameters collected from the corresponding patient electronic medical records. Exclusion criteria were preexisting diabetes mellitus, missing information and follow-up period of less than 12 mo. Data on demographic and clinical characteristics as well as anthropometric and laboratorial parameters were also collected. Patients were divided into two groups: With and without NODAT - for statistical comparison.

RESULTS

A total of 156 patients received kidney transplant during the study period, 125 of who were included in our analysis. NODAT was identified in 27.2% of the patients (n = 34; 53% female; mean age: 49.5 ± 10.8 years; median follow-up: 36.4 ± 2.5 mo). The incidence in the first year was 24.8%. The median time to diagnosis was 3.68 ± 5.7 mo after transplantation, and 76.5% of the patients developed NODAT in the first 3 mo. In the group that did not develop NODAT (n = 91), 47% were female, with mean age of 46.4 ± 13.5 years and median follow-up of 35.5 ± 1.6 mo. In the NODAT group, the pretransplant fasting plasma glucose (FPG) levels were significantly higher [101 (96.1-105.7) mg/dL vs 92 (91.4-95.8) mg/dL, P = 0.007] and pretransplant impaired fasting glucose (IFG) was significantly more frequent (51.5% vs 27.7%, P = 0.01). Higher pretransplant FPG levels and pretransplant IFG were found to be predictive risk factors for NODAT development [odds ratio (OR): 1.059, P = 0.003; OR: 2.772, P = 0.017, respectively].

CONCLUSION

NODAT incidence was high in our renal transplant recipients, particularly in the first 3 mo posttransplant, and higher pretransplant FPG level and IFG were risk factors.

Infection in Kidney Transplantation

Infection is an important cause of morbidity and mortality after kidney transplantation. It has been estimated that 70% of kidney transplant recipients will experience an infection episode within the first 3 years after transplantation (Dharnidharka et al. 2007). After cardiovascular disease, infection is the second leading cause of death in recipients with allograft function (Snyder et al. 2009). The immunosuppressive therapy required to prevent organ rejection places the kidney transplant recipient at increased risk for donor-derived, nosocomial, and community-acquired infections as well as reactivation of latent pathogens. Pretransplant screening, immunizations, and optimal antibacterial and antiviral prophylaxis can help to reduce the impact of infection. Awareness of the approach to infection in the transplant recipient including diagnostic and management strategies is essential to optimizing outcomes.

[Post-transplantation diabetes mellitus in kidney recipients]

Post-transplantation diabetes mellitus is defined as diabetes that is diagnosed in grafted patients. It affects 20 to 30 % of kidney transplant recipients, with a high incidence in the first year. The increasing age at transplantation and the rising incidence of obesity may increase its prevalence in the next years. Post-transplantation diabetes mellitus is associated with poor outcomes, such as mortality, cardiovascular events or graft dysfunction. Its occurrence is mainly related to immunosuppressive agents, affecting both insulin secretion and sensibility. Immunosuppressants may be iatrogenic, and as such, induce an early and transient diabetes. They may also precociously determine a permanent diabetes, acting here as a promoting factor in patients proned to the development of type 2 diabetes. Lastly, they may behave, far from transplantation, as an additional risk factor for type 2 diabetes. The screening, management and prognosis of these different subtypes of post-transplantation diabetes mellitus will be different.

Post-Transplant Diabetes Mellitus After Kidney Transplant in Hispanics and Caucasians Treated with Tacrolimus-Based Immunosuppression

Background

Development of post-transplant diabetes mellitus after kidney transplant (PTDM) significantly increases kidney graft loss and mortality. Several risk factors for PTDM have been reported, including Hispanic ethnicity and the use of calcineurin inhibitors and corticosteroids. The incidence and impact of PTDM in the Hispanic kidney transplant population is unknown.

Material/Methods

We retrospectively reviewed the medical records of 155 Hispanic and 124 Caucasian patients, who were not diabetics and underwent kidney transplant between January 2006 and December 2011. We analyzed their clinical outcomes at 12 months post-transplant, including the incidence of PTDM, acute rejection rates, and patient and graft survival.

Results

Hispanics who developed PTDM (n=22) were more than 10 years older and had higher body mass index (BMI) than Hispanics without PTDM (p<0.001 and p=0.001, respectively). Caucasians with PTDM (n=13) were non-significantly older (2.5 years) and had higher BMI than Caucasians without PTDM (p=0.526, p=0.043, respectively). The incidence of PTDM was not significantly different between Hispanics and Caucasians treated with tacrolimus-based immunosuppression (14.2% and 10.5%, respectively).

Conclusions

PTDM did not cause significant difference in short-term outcomes after kidney transplant in Hispanics or Caucasians. Larger multicenter prospective and long-term clinical trials are needed to validate these findings.

Genetic factors in pathogenesis of diabetes mellitus after kidney transplantation

Posttransplant diabetes mellitus (PTDM) is one of the major metabolic complications after transplantation of solid organs including the kidney. This type of diabetes mellitus affects allograft survival, cardiovascular complications and overall patient survival. The modifiable risk factors that contribute to PTDM include obesity, some viral infections (eg, hepatitis C virus, cytomegalovirus) and especially immunosuppressive drugs including corticosteroids, tacrolimus, cyclosporine and sirolimus. Currently, predisposing genetic factors have been considered important in PTDM development. The commonly evaluated genetic determinants include genes encoding transcription factors, cytokines, chemokines, adipokines, ionic channels, glucose transporters, cytochrome P450 enzymes and other enzymes metabolizing drugs, drug transporters. Unfortunately, the results of studies are inconclusive and differ between populations. There is a need for large genome-wide association study to identify the genetic risk factors associated with PTDM development.

Expansions of Cytotoxic CD4+CD28- T Cells Drive Excess Cardiovascular Mortality in Rheumatoid Arthritis and Other Chronic Inflammatory Conditions and Are Triggered by CMV Infection

A large proportion of cardiovascular (CV) pathology results from immune-mediated damage, including systemic inflammation and cellular proliferation, which cause a narrowing of the blood vessels. Expansions of cytotoxic CD4⁺ T cells characterized by loss of CD28 (“CD4⁺CD28⁻ T cells” or “CD4⁺CD28^null cells”) are closely associated with cardiovascular disease (CVD), in particular coronary artery damage. Direct involvement of these cells in damaging the vasculature has been demonstrated repeatedly. Moreover, CD4⁺CD28⁻ T cells are significantly increased in rheumatoid arthritis (RA) and other autoimmune conditions. It is striking that expansions of this subset beyond 1–2% occur exclusively in CMV-infected people. CMV infection itself is known to increase the severity of autoimmune diseases, in particular RA and has also been linked to increased vascular pathology. A review of the recent literature on immunological changes in CVD, RA, and CMV infection provides strong evidence that expansions of cytotoxic CD4⁺CD28⁻ T cells in RA and other chronic inflammatory conditions are limited to CMV-infected patients and driven by CMV infection. They are likely to be responsible for the excess CV mortality observed in these situations. The CD4⁺CD28⁻ phenotype convincingly links CMV infection to CV mortality based on a direct cellular-pathological mechanism rather than epidemiological association.

Hypomagnesemia and increased risk of new-onset diabetes mellitus after transplantation in pediatric renal transplant recipients

BACKGROUND

New-onset diabetes after transplantation (NODAT) is a significant co-morbidity following kidney transplantation. Lower post-transplant serum magnesium levels have been found to be an independent risk factor for NODAT in adult kidney transplant recipients.

METHODS

We undertook a retrospective analysis of risk factors for NODAT in pediatric renal transplant recipients at our institution with the aim of determining if hypomagnesemia confers a significant risk of developing NODAT in this patient population.

RESULTS

A total of 173 children with a median age at transplantation of 7.0 (range 1.3-17.5) years were included. Hypomagnesemia was found to be a significant independent risk factor for NODAT (p = 0.01). High trough tacrolimus levels were also independently associated with NODAT (p < 0.001). There was no significant association between NODAT and body mass index at the time of transplantation, monthly cumulative steroid dose or post-transplant cytomegalovirus viremia (p = 0.9, 0.6 and 0.7, respectively).

CONCLUSIONS

This study identifies hypomagnesemia as a significant independent risk factor for the development of NODAT in pediatric renal transplant recipients. Given the clear association between hypomagnesemia and NODAT in both adults and children following renal transplantation, further studies are merited to clarify the etiology of this association and to examine the effect of magnesium supplementation on NODAT.