Pretransplantation alpha-interferon therapy and the effect of hepatitis C virus infection on kidney allograft recipients

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.

Diabetes mellitus in dialysis and renal transplantation

Diabetes mellitus is the commonest cause of end-stage kidney failure worldwide and is a proven and significant risk factor for the development of cardiovascular disease. Renal impairment has a significant impact on the physiology of glucose homeostasis as it reduces tissue sensitivity to insulin and reduces insulin clearance. Renal replacement therapy itself affects glucose control: peritoneal dialysis may induce hyperglycaemia due to glucose-rich dialysate and haemodialysis often causes hypoglycaemia due to the relatively low concentration of glucose in the dialysate. Autonomic neuropathy which is common in chronic kidney disease (CKD) and diabetes increases the risk for asymptomatic hypoglycaemia. Pharmacological options for improving glycaemic control are limited due to alterations to drug metabolism. Impaired glucose tolerance and diabetes are also common in the post-kidney-transplant setting and increase the risk of graft failure and mortality. This review seeks to summarise the literature and tackle the intricacies of glycaemic management in patients with CKD who are either on maintenance haemodialysis or have received a kidney transplant. It outlines changes to glycaemic targets, monitoring of glycaemic control, the use of oral hypoglycaemic agents, the management of severe hyperglycaemia in dialysis and kidney transplantation patients.

Post-Transplantation Diabetes Mellitus

Solid organ transplantation (SOT) is an established therapeutic option for chronic disease resulting from end-stage organ dysfunction. Long-term use of immunosuppression is associated with post-transplantation diabetes mellitus (PTDM), placing patients at increased risk of infections, cardiovascular disease and mortality. The incidence rates for PTDM have varied from 10 to 40% between different studies. Diagnostic criteria have evolved over the years, as a greater understating of PTDM has been reached. There are differences in pathophysiology and clinical course of type 2 diabetes and PTDM. Hence, managing this condition can be a challenge for a diabetes physician, as there are several factors to consider when tailoring therapy for post-transplant patients to achieve better glycaemic as well as long-term transplant outcomes. This article is a detailed review of PTDM, examining the pathogenesis, diagnostic criteria and management in light of the current evidence. The therapeutic options are discussed in the context of their safety and potential drug-drug interactions with immunosuppressive agents.

Expert opinion on the management of renal manifestations of chronic HCV infection

Chronic HCV infection is a non-traditional (but modifiable) risk factor for chronic kidney disease and has been implicated in glomerular injury and nephrosclerotic disease. Three HCV direct-acting antiviral regimens are available for patients with severe kidney impairment: ombitasvir, paritaprevir with the pharmacokinetic enhancer ritonavir, and dasabuvir; glecaprevir plus pibrentasvir; and elbasvir plus grazoprevir. In patients with severe kidney impairment, sofosbuvir-free regimens are preferred because sofosbuvir accumulation has been associated with a progressive worsening of renal function. In this Review, we provide our expert opinion on the current HCV treatment paradigm and highlight the remaining issues that need to be overcome to improve the treatment of HCV in this population.

Post-transplantation diabetes in kidney transplant recipients: an update on management and prevention

Post-transplantation diabetes mellitus (PTDM) may severely impact both short- and long-term outcomes of kidney transplant recipients in terms of graft and patient survival. However, PTDM often goes undiagnosed is underestimated or poorly managed. A diagnosis of PTDM should be delayed until the patient is on stable maintenance doses of immunosuppressive drugs, with stable kidney graft function and in the absence of acute infections. Risk factors for PTDM should be assessed during the pre-transplant evaluation period, in order to reduce the likelihood of developing diabetes. The oral glucose tolerance test is considered as the gold standard for diagnosing PTDM, whereas HbA1c is not reliable during the first months after transplantation. Glycaemic targets should be individualised, and comorbidities such as dyslipidaemia and hypertension should be treated with drugs that have the least possible impact on glucose metabolism, at doses that do not interact with immunosuppressants. While insulin is the preferred agent for treating inpatient hyperglycaemia in the immediate post-transplantation period, little evidence is available to guide therapeutic choices in the management of PTDM. Metformin and incretins may offer some advantage over other glucose-lowering agents, particularly with respect to risk of hypoglycaemia and weight gain. Tailoring immunosuppressive regimens may be of help, although maintenance of good kidney function should be prioritised over prevention/treatment of PTDM. The aim of this narrative review is to provide an overview of the available evidence on management and prevention of PTDM, with a focus on the available therapeutic options.

Post-Transplant Diabetes Mellitus: Causes, Treatment, and Impact on Outcomes

Post-transplant diabetes mellitus (PTDM) is a frequent consequence of solid organ transplantation. PTDM has been associated with greater mortality and increased infections in different transplant groups using different diagnostic criteria. An international consensus panel recommended a consistent set of guidelines in 2003 based on American Diabetes Association glucose criteria but did not exclude the immediate post-transplant hospitalization when many patients receive large doses of corticosteroids. Greater glucose monitoring during all hospitalizations has revealed significant glucose intolerance in the majority of recipients immediately after transplant. As a result, the international consensus panel reviewed its earlier guidelines and recommended delaying screening and diagnosis of PTDM until the recipient is on stable doses of immunosuppression after discharge from initial transplant hospitalization. The group cautioned that whereas hemoglobin A1C has been adopted as a diagnostic criterion by many, it is not reliable as the sole diabetes screening method during the first year after transplant. Risk factors for PTDM include many of the immunosuppressant medications themselves as well as those for type 2 diabetes. The provider managing diabetes and associated dyslipidemia and hypertension after transplant must be careful of the greater risk for drug-drug interactions and infections with immunosuppressant medications. Treatment goals and therapies must consider the greater risk for fluctuating and reduced kidney function, which can cause hypoglycemia. Research is actively focused on strategies to prevent PTDM, but until strategies are found, it is imperative that immunosuppression regimens are chosen based on their evidence to prolong graft survival, not to avoid PTDM.

Novel views on new-onset diabetes after transplantation: development, prevention and treatment

New-onset diabetes after transplantation (NODAT) is associated with increased risk of allograft failure, cardiovascular disease and mortality, and therefore, jeopardizes the success of renal transplantation. Increased awareness of NODAT and the prediabetic states (impaired fasting glucose and impaired glucose tolerance, IGT) has fostered previous and present recommendations, based on the management of type 2 diabetes mellitus (T2DM). Unfortunately, the idea that NODAT merely resembles T2DM is potentially misleading, because the opportunity to initiate adequate anti-hyperglycaemic treatment early after transplantation might be given away for 'tailored' immunosuppression in patients who have developed NODAT or carry personal risk factors. Risk factor-independent mechanisms, however, seem to render postoperative hyperglycaemia with subsequent development of overt or 'full-blown' NODAT, the unavoidable consequence of the transplant and immunosuppressive process itself, at least in many cases. A proof of the concept that timely preventive intervention with exogenous insulin against post-transplant hyperglycaemia may decrease NODAT was recently provided by a small clinical trial, which is awaiting confirmation from a multicentre study. However, because early insulin therapy aimed at beta-cell protection seems to contrast the currently recommended, stepwise approach of 'watchful waiting' prior to pancreatic decompensation, we here aim at reviewing recent concepts regarding the development, prevention and treatment of NODAT, some of which seem to challenge the traditional view on T2DM and NODAT. In summary, we suggest a novel, risk factor-independent management approach to NODAT, which includes glycaemic monitoring and anti-hyperglycaemic treatment in virtually everybody after transplantation. This approach has widespread implications for future research and is intended to tackle NODAT and also ultimately cardiovascular disease.

Treatment of dialysis patients with chronic hepatitis C using pegylated interferon and low-dose ribavirin

BACKGROUND

No safe and effective therapy exists for chronic hepatitis C in dialysis patients. Available data on the antiviral treatment of hepatitis C in dialysis population is mostly based on standard interferon monotherapy.

OBJECTIVES

We conducted a prospective, cohort trial with combined therapy (pegylated-interferonalpha-2a (135 mcg/week) plus low dose ribavirin (200 mg/day)) for chronic hepatitis C in 15 patients undergoing long-term dialysis. Twelve patients had HCV genotype 1a/1b, three were co-infected with human immunodeficiency virus (HIV), and two had compensated cirrhosis. End-points were sustained viral response and adverse effects.

RESULTS

Sustained virological response was obtained in four patients (including two with HCV genotype 1); the SVR rate was 28.6% (4/14), on an intention-to-treat analysis. One subject with SVR had compensated cirrhosis. All HIV co-infected patients had well controlled HIV and one of them (33%) reached SVR. Seven (50%) of the 14 patients were non-responders, two of which relapsed after discontinuation of therapy. Drop-out rate was 71.4% (10/14). The most frequent side-effect was anemia, which required ribavirin discontinuation in three patients; seven (47%) patients received blood transfusions. Two patients died (week 4 and 14) of causes related to cardiovascular disease, which was frequent in our cohort. Two subjects were hospitalized and discontinued therapy (week 1, and 27).

CONCLUSIONS

Results from this study showed that about one-third of HD patients achieved sustained virological response with pegylated-interferon-alpha-2a plus low-dose ribavirin; however, tolerance to antiviral treatment was unsatisfactory. Well- controlled HIV infection should not be a contraindication to HCV therapy in dialysis patients. Prospective, controlled clinical trials of combined antiviral therapy targeted at HCV in chronic kidney disease population are indicated.

Transplant-associated hyperglycemia

As patient survival after solid organ transplantation continues to improve, comorbidites associated with chronic hyperglycemia will assume increasing importance in limiting outcomes and quality of life. New-onset diabetes mellitus commonly occurs in the posttransplant setting and is associated with multiple complications including graft loss, cardiovascular disease, infection, and death. Furthermore, recent studies have begun to highlight the very high posttransplant prevalence and the significant cardiovascular implications of the prediabetic states of impaired fasting glucose and impaired glucose tolerance, indicating that the overall burden of transplantation-associated hyperglycemia is far greater than previously appreciated. Shared and distinct pathogenic factors and clinical repercussions exist among the organ-specific transplant scenarios. Diabetogenic immunosuppressive agents are common to all organ transplant settings, whereas glucose regulation is also strained by the restoration of failed hepatic and renal function. The atherogenic properties of hyperglycemia are particularly significant in the kidney transplant population, which has a marked predisposition to cardiovascular disease, whereas accelerated cardiac allograft vasculopathy and liver fibrosis have been associated with hyperglycemia in the heart and liver transplant settings, respectively. Aggressive screening will effectively detect transplant-associated hyperglycemia, whereas risk factor modification, lifestyle intervention and, where appropriate, drug therapy, may decrease its impact. Topics of future investigation should include the use of emerging diabetes therapies and avenues for the prevention and reversal of transplant-associated hyperglycemia.

Hepatitis C virus infection in haemodialysis and kidney transplant patients

Chronic infection with hepatitis C virus (HCV) is an important global health problem. The prevalence of HCV is significantly higher in haemodialysis and kidney transplant patients, as compared to the general population. In spite of the relatively milder liver disease activity reported in HCV-infected haemodialysis patients, HCV infection adversely affects survival. Likewise, HCV has a detrimental effect on both patient and graft survival after kidney transplantation. However, patient survival is significantly better with kidney transplantation compared to remaining on dialysis; therefore, HCV infection alone should not be a contraindication to transplantation. Combination antiviral therapy with pegylated interferon-alpha and low-dose ribavirin is currently evolving in haemodialysis patients. Interferon-alpha (standard/pegylated) is relatively contraindicated after kidney transplantation because of an increased risk of allograft rejection. Therefore, antiviral treatment of transplant candidates while on dialysis remains the best option and may avoid the risk of HCV-associated liver and renal disease after transplantation. Large multi-centre clinical trials are required in HCV-infected haemodialysis and kidney transplant patients in order to define optimal therapeutic strategies before and after transplantation.

New-onset diabetes mellitus in the kidney recipient: diagnosis and management strategies

Advancing care has markedly improved survival after kidney transplantation, leaving patients susceptible to the effects of chronic transplant-associated morbidities. New-onset diabetes mellitus (NODM) is common in kidney recipients, threatening health and longevity by predisposing to microvascular and cardiovascular disease and by reducing graft survival. A strong rationale therefore exists for the aggressive treatment of NODM in kidney recipients to limit these complications. Screening for diabetes should be systematic and should span the pre- and posttransplantation periods. Once NODM is diagnosed in the kidney transplant patient, a comprehensive plan of therapy should be used to achieve treatment targets. As in the general population, treatment includes lifestyle modification and drug therapy as needed, but transplant-specific factors add complexity to the care of kidney recipients. Among these, minimizing immunosuppression-related toxicity without compromising graft outcomes is of paramount importance. Preexisting allograft functional impairment and the potential for significant interactions with immunosuppressive agents mandate that the expanding armamentarium of hypoglycemic agents be used with care. A team-oriented treatment approach that capitalizes on the collective expertise of transplant physicians, diabetologists, nurse-educators, and dieticians will optimize both glycemic control and the overall health of hyperglycemic kidney recipients.

Efficacy and safety of pegylated-interferon α-2a in hemodialysis patients with chronic hepatitis C

AIM: To evaluate the efficacy and safety of pegylated-interferon alpha-2a in hemodialysis patients with chronic hepatitis C.

METHODS: Thirty-six hemodialysis patients with chronic hepatitis C were enrolled in a controlled and prospective study. All patients were treatment naive, positive tested for anti-HCV antibodies, and positive tested for serum HCV-RNA. Twenty-two patients received 135 &mgr;g peglyated-interferon α-2a weekly for 48 wk (group A). The remaining patients were left untreated, eleven refused therapy, and three were not candidates for kidney transplantation and were allocated to the control group (group B). At the end of the treatment biochemical and virological response was evaluated, and 24 wk after completion of therapy sustained virological response (SVR) was assessed. Side effects were monitored.

RESULTS: Of 22 hemodialysis patients, 12 were male and 10 female, with a mean age of 35.2 ± 12.1 years. Virological end-of-treatment response was observed in 14 patients (82.4%) in group A and in one patient (7.1%) in group B (P = 0.001). Sustained virological response was observed in 11 patients (64.7%) in group A and in one patient in group B (7.1%). Biochemical response parameters normalized in 10/14 patients (71.4%) at the end of the treatment. ALT levels in group B were initially high in six patients and normalized in one of them (25%) at the end of the 48 wk. In five patients (22.7%) therapy had to be stopped at mo 4 due to complications of weakness, anemia, and bleeding.

CONCLUSION: SVR could be achieved in 64.7% of patients on hemodialysis with chronic hepatitis C by a treatment with peglyated-interferon α-2a. Group A had a significantly better efficacy compared to the control group B, but the side effects need to be concerned.

Transplant-associated hyperglycemia: a new look at an old problem

New-onset diabetes has long been recognized as a common complication of kidney transplantation, promoting cardiovascular disease, death, and graft failure. Studies in recent years have begun to highlight the very high posttransplantation prevalence of the prediabetic states of impaired fasting glucose and impaired glucose tolerance and the significant repercussions of these states on cardiovascular health. Therefore, the overall burden of transplant-associated hyperglycemia (TAH), which encompasses new-onset diabetes and the prediabetic states, is far greater than previously appreciated. The kidney transplant population is predisposed to insulin resistance and to additional insults of hypertension and hyperlipidemia that, together with hyperglycemia, compose the metabolic syndrome and promote atherosclerosis. When recipients with an underlying, frequently nonmodifiable predisposition to glucose dysregulation encounter transplant-specific, often modifiable, diabetogenic exposures, TAH manifests. Aggressive screening will effectively detect TAH, whereas risk factor modification, lifestyle intervention, and, when appropriate, drug therapy may decrease its impact. Topics of future investigation should include the use of emerging diabetes therapies and avenues for the prevention and reversal of TAH.

Efficacy and tolerability of pegylated-interferon alpha-2a in hemodialysis patients with chronic hepatitis C

BACKGROUND AND AIM

Hepatitis C virus (HCV) is prevalent in hemodialysis (HD) patients. These patients experience more side-effects with antiviral treatment. The aim of the present study was to evaluate the efficacy and tolerability of pegylated interferon (PEG-IFN) alpha-2a in chronic hemodialysis patients with chronic hepatitis C.

METHODS

Twenty-five patients were included into the study. All of the patients were interferon naive, anti-HCV antibodies positive and polymerase chain reaction HCV-RNA positive. Twelve of the patients received PEG-IFN alpha-2a at a dose of 135 microg weekly for 48 weeks (Group 1). The remaining 13 patients who received no specific treatment were used as controls (Group 2). The patients were prospectively followed up for a period of 18 months. Biochemical and virological responses were evaluated at the end of the study period (end-of-treatment response) and 6 months after the completion of therapy (sustained response).

RESULTS

Virological end-of-treatment response was observed in 10 patients (83.4%) in Group 1 and one patient (7.7%) in Group 2 (P < 0.001). Sustained virological response was observed in nine patients (75%) in Group 1 and one patient (7.7%) in Group 2 (P < 0.001). Alanine aminotransferase (ALT) levels were initially increased in seven patients in Group 1 and normalized in five of these patients at the end of the treatment and sustained biochemical response was 71.4%. In contrast, ALT levels in Group 2 were initially high in five patients and normalized in two of them (40%) at the end of the 48 weeks. Even if most of the patients experienced several side-effects (anemia 75%, fatigue 58.3%, thrombocytopenia 33.3% and leukopenia 33.3%), they did not impose the discontinuation of the treatment.

CONCLUSION

The present study showed that PEG-IFN alpha-2a for 48 weeks is efficacious and well tolerated in hemodialysis patients with HCV.

Hepatitis C virus seropositivity at the time of renal transplantation in the United States: associated factors and patient survival

National statistics for patient characteristics and survival of renal transplant recipients positive for hepatitis C virus (HCV+) at the time of renal transplant are presented. A historical cohort analysis of 33479 renal transplant recipients in the United States Renal Data System from 1 July, 1994 to 30 June, 1997 has been carried out. The medical evidence form was also used for additional variables, but because of fewer available values, this was analyzed in a separate model. Outcomes were patient characteristics and survival associated with HCV+. Of 28692 recipients with valid HCV serologies, 1624 were HCV+ at transplant (5.7% prevalence). In logistic regression analysis, HCV+ was associated with African-American race, male gender, cadaveric donor type, increased duration of pre-transplant dialysis, previous transplant, donor HCV+, recipient (but not donor) age, serum albumin, alcohol use, and increased all-cause hospitalizations. Diabetes and IgA nephropathy were less associated with HCV+. Total all-cause, unadjusted mortality was 13.1% in HCV+ vs. 8.5% in HCV- patients (p <0.01 by log rank test). In Cox regression, mortality was higher for HCV+ (adjusted hazard ratio = 1.23, 95% confidence interval = 1.01-1.49, p = 0.04). HCV+ recipients were more likely to be African-American, male, older, and to have received repeat transplants and donor HCV+ transplants. HCV+ recipients also had substantially longer waiting times for transplant. In contrast to recent studies, diabetes did not have an increased association with HCV+, perhaps due to limitations of the database. HCV+ recipients had increased mortality and hospitalization rates compared with other transplant recipients.

Interferon therapy in haemodialysis patients with acute hepatitis C virus infection and factors that predict response to treatment

In view of the high rate of chronicity of acute hepatitis C and the low efficacy of interferon (IFN) treatment in advanced liver disease, it may be beneficial to treat patients during the acute phase of the infection. Here we assessed the effects of variable-dose IFNalpha-2b treatment in haemodialysis patients with acute hepatitis C virus (HCV) infection, and identified factors that may predict response to this therapy. The study population included 67 patients, but 14 were excluded due to side-effects or because they were lost to follow-up. Seventeen patients who received no specific treatment were used as controls (Group 1). Sixteen and 20 patients received low-(3 MU) and high-dose (6-10 MU) IFNalpha-2b three times weekly for 3 months (Groups 2 and 3, respectively). Virological end-of-treatment response (ETR) was observed in 1 (5.6%), 13 (56.5%), and 17 (65.4%) patients in Groups 1, 2, and 3, respectively, and virological sustained response (SR) was observed in 1 (5.6%), 6 (26.1%), and 13 (50%) patients in the three groups. The rates of virological ETR and SR in the treated groups were significantly higher than those of the control group (P < 0.01 for all comparisons). In multivariate logistic regression analysis, single stranded confirmational polymorphysm (SSCP) band number (P=0.02) was the only factor that was significantly associated with virological SR. In conclusion, IFN-alpha treatment initiated during the acute phase of HCV infection is associated with a higher rate of virological ETR and SR. This study suggested that quasispecies heterogeneity has predictive value with regard to virological SR.