Anemia after kidney transplantation

Relationship of hemoglobin levels with outcomes in deceased donor kidney transplant: a retrospective cohort study

INTRODUCTION

Anemia is frequent in patients undergoing replacement therapy for kidney failure. Anemia in the pre- and post-transplantation period might be related to kidney transplant outcomes. The current study therefore sought to assess the relationship between anemia, delayed allograft function (DGF), chronic kidney allograft dysfunction (CAD), and death from any cause following kidney transplantation from a deceased donor.

METHODS

This was a retrospective study with 206 kidney transplant patients of deceased donors. We analyzed deceased donors' and kidney transplant patients' demographic data. Moreover, we compared biochemical parameters, anemia status, and medicines between DGF and non-DGF groups. Afterward, we performed a multivariate analysis. We also evaluated outcomes, such as CAD within one year and death in ten years.

RESULTS

We observed a lower frequency of pre-transplant hemoglobin concentration (Hb) but higher frequency of donor-serum creatinine and red blood transfusion within one week after transplantation in the group with DGF. In addition, there was an independent association between Hb concentration before transplantation and DGF [OR 0.252, 95%CI: 0.159-0.401; p < 0.001]. There was also an association between Hb concentration after six months of kidney transplantation and both CAD [OR 0.798, 95% CI: 0.687-0.926; p = 0.003] and death from any cause.

CONCLUSION

An association was found between pre-transplantation anemia and DGF and between anemia six months after transplantation and both CAD and death by any cause. Thus, anemia before or after transplantation affects the outcomes for patients who have undergone kidney transplantation from a deceased donor.

Hemophagocytic lymphohistiocytosis after solid organ transplantation: A challenge for clinicians

Hemophagocytic lymphohistiocytosis (HLH) is a rare inflammatory disorder with a high mortality rate and a wide range of symptoms. Solid organ transplantation, which provides patients with a unique immunosuppressive state, is a less common predisposing factor for HLH. HLH after solid organ transplantation (HLH-SOT) is very rare and fatal. It is hard to diagnose and treat and extremely understudied. The use of immunosuppressants makes the situation of HLH-SOT more complex. This review summarizes the existing literature on HLH after solid organ transplantation and describes its triggers and symptoms, focusing on its diagnosis and treatment. We performed a literature search of case reports, case series, letters to the editor, and clinical quizzes describing patients with HLH after solid organ transplantation (HLH-SOT). We provide recommendations on the diagnosis protocol and treatment strategy based on the existing evidence.

Association between blood transfusion after kidney transplantation and risk for the development of de novo HLA donor-specific antibodies and poor clinical outcomes: A single-center retrospective study

BACKGROUND

Blood transfusion after kidney transplantation may increase the risk of sensitization and development of de novo human leukocyte antigen (HLA) donor-specific antibodies (DSAs). This study aimed to evaluate whether blood transfusion during the first year after kidney transplantation influences the development of de novo DSAs and clinical outcomes of kidney transplantation recipients.

METHODS

This retrospective cohort study included nonsensitized first-time kidney transplantation recipients at Tianjin First Central Hospital from 2010 to 2022. The incidence of de novo DSA development and clinical outcomes between the groups were compared. Luminex single antigen beads were used to monitor DSAs.

RESULTS

Of the 538 non-HLA-sensitized kidney transplantation recipients included in the study, 164 patients who received at least one unit of leukoreduced red blood cell transfusion within the first year (the transfused group), whereas the remaining 374 patients received no blood transfusion (the non-transfused group). Our analysis showed that there was a significant difference in the development of de novo DSAs and de novo anti-class I HLA-Ab between the two groups. Indeed, the transfused recipients had a higher serum creatinine and lower estimated glomerular filtration rate (eGFR) at 1-, 6-, and 12-month (all p > 0.05) after transplantation. Futhermore, a higher incidence of CMV infection, antibody-mediated rejection (AMR), hyper acute rejection (HAR), and delayed graft function (DGF) was identified in the transfused group (all p < 0.05). The graft survival was lower in the transfused group compared with patients in the non-transfused group (P = 0.002). Blood transfusion post-transplantation was a risk factor for de novo DSAs development but not an independent predictive factor for AMR and graft loss (odds ratio = 2.064 [1.243-3.429], p = 0.005).

CONCLUSIONS

Our study showed that blood transfusion after transplantation is associated with the occurrence of de novo DSAs increasing an immunological risk for poor clinical outcomes for kidney transplantation recipients.

Evaluating the utilisation and expenditure patterns of erythropoietin stimulating agents and immunosuppressants in Australian chronic kidney disease patients

Objectives

This study aimed to characterise utilisation and expenditure patterns associated with erythropoietin stimulating agents (ESAs) (darbepoetin alfa, epoetin alfa, epoetin beta, epoetin lambda and methoxy polyethylene glycol-epoetin beta) and immunosuppressants (mycophenolate, tacrolimus, ciclosporine, sirolimus and everolimus) in the Australian chronic kidney disease (CKD) population from 2010–2018.

Methods

Utilisation and expenditure data for each drug were obtained from the Pharmaceutical Benefit Scheme and Highly Specialised Drugs program. Utilisation data were provided a number of dispensing per year, which was then converted to the daily defined dose per 1000 population per day for each year. Temporal trends were then analysed.

Key findings

Over the study period, utilisation of methoxy polyethylene glycol-epoetin beta and epoetin lambda rose by 13.7 and 81.4-fold, respectively. Contrastingly, the utilisation of darbepoetin alfa, epoetin alfa and epoetin beta declined by 6%, 42% and 70%, respectively. In 2018, tacrolimus, sirolimus, everolimus and mycophenolate utilisation was up 126%, 16.9%, 125% and 182% respectively; conversely, ciclosporine utilisation dropped 19%. Total Australian expenditure on all ESAs examined remained stable at around AUD 128 million over the study period, while total Australian expenditure across all immunosuppressants increased 1.1-fold reaching just over AUD 98 million.

Conclusions

It appears that immunosuppressant utilisation and expenditure are rising as transplantation rates in Australia continue to increase. Conversely, ESA utilisation and expenditure remained relatively unchanged over the study period. This may be due to increasing concerns around the safety of ESAs offsetting the increasing number of people with CKD.

Anaemia associated with Tacrolimus: A case report and literature review

WHAT IS KNOWN AND OBJECTIVE

Tacrolimus (FK506), an immunosuppressant, is a popular option for combination drug treatment of nephrotic syndrome. It is well-tolerated by most patients and rarely induces anaemia. We report a case of anaemia in a girl with immunoglobulin A (IgA) nephropathy that occurred after FK506 treatment.

CASE SUMMARY

A 12-year-old girl received a combination treatment of FK506 and hormones. During the therapy, the red blood cells (RBCs), haemoglobin (HGB) and red blood cell-specific volume (HCT) continued to decrease following an increase in the whole blood concentration of FK506. Moderate anaemia was found in the patient. The levels of RBC, HGB and HCT gradually improved after discontinuation of the FK506 and symptomatic treatment.

WHAT IS NEW AND CONCLUSION

The mechanism by which FK506 induces anaemia remains unclear. The genetic polymorphisms of CYP3A5 or the chemical structure may have an effect in the onset of the disease. Thus, when a patient presents with a newly developed anaemic condition during FK506 treatment, after elimination of haematuria and any underlying disease, the possibility of the effect of the medication should be considered.

Changes in clinical indicators related to the transition from dialysis to kidney transplantation-data from the ERA-EDTA Registry

Background

Kidney transplantation should improve abnormalities that are common during dialysis treatment, like anaemia and mineral and bone disorder. However, its impact is incompletely understood. We therefore aimed to assess changes in clinical indicators after the transition from chronic dialysis to kidney transplantation.

Methods

We used European Renal Association–European Dialysis and Transplant Association Registry data and included adult dialysis patients for whom data on clinical indicators before and after transplantation (2005–15) were available. Linear mixed models were used to quantify the effect of transplantation and of time after transplantation for each indicator.

Results

In total, 16 312 patients were included. The mean age at transplantation was 50.1 (standard deviation 14.2) years, 62.9% were male and 70.2% were on haemodialysis before transplantation. Total, low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterol and triglycerides increased right after transplantation but decreased thereafter. All other indicators normalized or approached the target range soon after transplantation and these improvements were sustained for the first 4 years of follow-up. In patients with higher estimated glomerular filtration rate (eGFR) levels (30–60 and >60 mL/min/1.73 m²), the improvement of haemoglobin, ferritin, ionized calcium, phosphate, parathyroid hormone, HDL cholesterol, triglycerides, albumin and C-reactive protein levels was more pronounced than in patients with a lower eGFR (<30 mL/min/1.73 m²).

Conclusions

Except for total cholesterol, LDL cholesterol and triglycerides, all clinical indicators improved after transplantation. These improvements were related to eGFR. Nevertheless, values remained out of range in a considerable proportion of patients and anaemia and hyperparathyroidism were still common problems. Further research is needed to understand the complex relationship between eGFR and the different clinical indicators.

Pure Red Cell Aplasia After Kidney Transplantation: Parvovirus B19 Culprit or Coincidence?

Background

Anemia is present even in long-term observation after kidney transplantation. Observational study results indicate the presence of chronic post-transplantation anemia in 1 in 3 recipients. An extreme form of erythroid line dysfunction is pure red cell aplasia (PRCA). It may be caused by immunosuppressive treatment per se or a side effect, opportunistic pathogen activation. Parvovirus B19 (PV B19) infection is quite likely the cause of refractory normocytic anemia in immunocompromised patients.

Case Report

In this case report we discuss biological and clinical features of this phenomenon and the treatment strategies, based on 2 PRCA cases in kidney transplant recipients. Additionally, a systematic review of published reports of PV B19 related PRCA in kidney recipients is presented.

Conclusions

PV replication should be ruled out in cases of persistent and/or refractory anemia after kidney transplantation. The established first-line treatment of PRCA is passive immunization. Taking into account cost effectiveness, a decrease in immunosuppression load is reasonable under careful control of allograft function.

Nutritional Management for Chronic Kidney Disease Patients who Undergo Bariatric Surgery: A Narrative Review

Bariatric surgery (BS) may be effective for chronic kidney disease (CKD) patients by reducing microalbuminuria and proteinuria, and by facilitating their meeting inclusion criteria for kidney transplantation. However, nutritional management for this population is complex and specific guidelines are scarce. A literature search was performed to create dietetic practice for these patients based on the most recent evidence. For the purposes of nutritional recommendations, we divided the patients into 2 subgroups: 1) patients with CKD and dialysis, and 2) patients after kidney transplantation. Before surgery, nutritional care includes nutritional status evaluation and adjusting doses of supplements to treat deficiencies and daily nutrient intake according to the dietary restrictions derived from kidney disease, including quantities of fluids, protein, phosphorus, potassium, and vitamins. After BS, these patients are at major risk for lean body mass loss, malnutrition and dehydration because of fluid restriction and diuretics. Postoperative nutritional recommendations should be carefully tailored according to CKD nutritional limitations and include specific considerations regarding protein, fluids, and supplementation, in particular calcium, vitamin A, and vitamin D. Nutritional management of CKD and kidney transplant patients undergoing BS is challenging and future studies are required to establish uniform high-level evidence-based guidelines.

Clinical risk factors associated with the post-transplant anemia in kidney transplant patients

BACKGROUND

Anemia is a very common occurrence in post-renal transplant patients. Post-transplantation anemia (PTA) is associated with significant graft loss or cardiovascular morbidity. The objective of this study is to identify clinical risk factors associated with anemia after kidney transplantation.

METHODS

Our retrospective cohort study included a total of 570 renal transplant recipients. For the definition of anemia, we adopted "the lower limit of normal for Hgb concentration of blood" proposed by Beutler E and Waalen J [14], which has adjustments for age, gender and ethnicity. Post-transplant anemia (PTA) was defined as anemia that arose between 30 and 180days after transplantation. Based on this definition, of the 570 renal transplant recipients, 344 patients (62.1%) experienced PTA. The patients were divided into anemic and non-anemic groups, and a total of 20 clinical factors were compared between the two groups.

RESULTS

In the univariate analysis, age, race, multiple transplants, delayed graft function (DGF), and use of tacrolimus, sirolimus, thymoglobulin, ganciclovir, ACE inhibitors, and ARBs were associated with PTA. In the multivariate analysis, age (>60years old, OR=2.62, p=0.001), race (OR=2.54, p=0.001), and use of sirolimus (OR=2.01, p=0.019), antiviral agents (OR=1.96, p=0.015), thymoglobulin (OR=1.86, p=0.011), and DGF (OR=2.78, p=0.001) remained significant.

CONCLUSION

The current results show that undergoing a transplant at age 60 or older, use of sirolimus, antiviral agents, and thymoglobulin are independent clinical risk factors associated with PTA. In terms of ethnicity, AA, MEA, or PI is higher risk for PTA and Hispanic is significantly lower risk for PTA compared to Caucasians.

Laboratory use of hepcidin in renal transplant recipients

Hepcidin is a small peptide with a critical role in cellular iron homeostasis, as it regulates utilization of stored iron and antimicrobial defense in inflammation (bacterial and fungal). Since it was isolated in 2000, and especially in the last decade, numerous studies aimed to evaluate the clinical use of plasma and urine hepcidin as a marker of anemia, especially anemia of chronic disease and post-transplant anemia (PTA). Hepcidin regulation is delicately tuned by two inflammatory pathways activated by interleukin-6 (IL-6) and bone morphogenic proteins (BMPs) and iron regulated pathway sensitive to circulating transferin-iron (TR-Fe) complex. BMP-mediated pathway and TR-Fe sensitive pathway seem to be connected by hemojuveline, a BMP co-factor that interacts with transferine receptor 2 (TRF2) in cases of high TR-Fe circulatory concentration. In addition to these regulatory mechanisms other regulators and signaling pathways are being extensively researched.
Hepcidin has been identified as an important contributor to morbidity and mortality in end stage renal disease (ESRD) but no such association has jet been found in case of PTA. However, there is an association between higher doses of erythropoiesis-stimulating agents (ESA) and mortality in the posttransplant period and the assumption that hepcidin might play a role in ESA resistance in PTA. Thus the review’s main goal was to summarize papers published on the association of hepcidin with PTA, give up-to-date information on hepcidin regulation and on potential therapeutics that optimize hepcidin regulation. We also compared the performances of tests for hepcidin determination and reviewed research on immunosuppressants’ (IS) effect on hepcidin concentration.

Post-renal transplantation anemia at 12 months: prevalence, risk factors, and impact on clinical outcomes

PURPOSE

To investigate any association between post-transplantation anemia (PTA) and clinical outcomes following living donor kidney transplantation.

METHODS

We retrospectively evaluated 887 patients who received living donor kidney transplantations at our medical center between January 2006 and December 2012 to evaluate whether PTA, defined as serum hemoglobin (Hb) levels of <130 g/l in men and <120 g/l in women, at 12 months is associated with post-transplant outcomes, including graft function, death-censored graft survival, or patient survival.

RESULTS

The prevalence of PTA at 1, 3, 6, and 12 months was 84.3, 39.5, 26.2, and 21.6 %, respectively. Donor age [hazard ratio (HR), 1.03; 95 % confidence interval (CI) 1.01-1.05] and acute rejection (HR 2.13; 95 % CI 1.28-3.54) were found to be independent risk factors for PTA at 12 months. Recipient age (HR 0.98; 95 % CI 0.95-1.00), pre-transplantation Hb levels (HR 0.99; 95 % CI 0.98-1.00), and estimated glomerular filtration rates (eGFRs) at 12 months (HR 0.96; 95 % CI 0.94-0.97) were found to confer slight protection against PTA at 12 months. PTA at 12 months was associated with increased graft loss (HR 1.046; 95 % CI 1.045-1.046). For each increase in anemia degree, there was a 2.77-fold greater risk of graft loss (HR 2.77; 95 % CI 1.50-5.13). When stratified according to eGFR, PTA was found to be a predictor of graft loss in patients with an eGFR of <60 ml/min/1.73 m(2) (HR 4.57; 95 % CI 1.98-10.56) but not in patients with an eGFR of >60 ml/min/1.73 m(2) (HR 1.89; 95 % CI 0.13-27.78). PTA was not found to be a predictor of patient survival.

CONCLUSIONS

Anemia is common after kidney transplantation, and its prevalence declines with time after transplantation. Presence of anemia at 12 months post-transplant was an independent predictor of graft loss, with higher risk of graft loss in patients with anemia and poorer kidney functions.

Bone marrow biopsy in patients with renal transplant: spectrum of findings and diagnostic use

OBJECTIVES

Renal transplant may be complicated by cytopenia, fever of unknown etiology, or hematolymphoid malignancies. Bone marrow biopsy may be indicated to evaluate these complications. However, to the best of our knowledge, no previous study has systematically documented the characteristics of bone marrow biopsy in these patients. The present study reports the range of bone marrow findings in renal transplant recipients.

MATERIALS AND METHODS

We selected 85 patients who underwent bone marrow biopsy among 1745 renal transplant recipients who had transplant at Ba şkent University from January 1990 to December 2013. The files of these patients were reviewed for age, sex, age at renal transplant, underlying renal disease, donor type, immunosuppressive therapy, presence or absence of acute humoral or cellular rejection, duration between transplant and bone marrow biopsy, indication for bone marrow biopsy, and histopathologic diagnoses of bone marrow biopsies.

RESULTS

The most common cause of renal insufficiency leading to transplant in this patient group was unknown etiology, observed in 24 patients (28.2%). The most common indication for bone marrow biopsy was blood cytopenia, detected in 56 patients (65.9%). Neoplastic involvement of the bone marrow was detected in 6 patients (7.1%), all of which were hematolymphoid malignancies. Corticosteroids were the most commonly used immunosuppressive agents, administered to all patients.

CONCLUSIONS

Bone marrow biopsy provides important information in renal transplant recipients, especially in cases of neoplastic bone marrow involvement, specific inflammation, and amyloidosis, which are uncommon in this patient group. The overall diagnostic use is related to the individual situation of each patient.

An Association between BK Virus Replication in Bone Marrow and Cytopenia in Kidney-Transplant Recipients

The human polyomavirus BK (BKV) is associated with severe complications, such as ureteric stenosis and polyomavirus-associated nephropathy (PVAN), which often occur in kidney-transplant patients. However, it is unknown if BKV can replicate within bone marrow. The aim of this study was to search for BKV replication within the bone marrow of kidney-transplant patients presenting with a hematological disorder. Seventy-two kidney-transplant patients underwent bone-marrow aspiration for cytopenia. At least one virus was detected in the bone marrow of 25/72 patients (35%), that is, parvovirus B19 alone (n = 8), parvovirus plus Epstein-Barr virus (EBV) (n = 3), cytomegalovirus (n = 4), EBV (n = 2), BKV alone (n = 7), and BKV plus EBV (n = 1). Three of the eight patients who had BKV replication within the bone marrow had no detectable BKV replication in the blood. Neutropenia was observed in all patients with BKV replication in the bone marrow, and blockade of granulocyte maturation was observed. Hematological disorders disappeared in all patients after doses of immunosuppressants were reduced. In conclusion, an association between BKV replication in bone marrow and hematological disorders, especially neutropenia, was observed. Further studies are needed to confirm these findings.

Cardiovascular death in kidney recipients treated with renin-angiotensin system blockers

BACKGROUND

Angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin receptor blockers (ARBs) are widely prescribed after kidney transplantation, but evidence for an improvement in outcomes is mixed. A recent trial demonstrated a significantly lower incidence of major cardiovascular events in ACEI-treated recipients.

METHODS

Collaborative Transplant Study data on cardiovascular death during years 2 to 10 after kidney transplantation in patients with a functioning graft were analyzed according to whether ACEI/ARB or other antihypertensive therapy (excluding diuretics) was administered at year 1.

RESULTS

Of 39,251 transplants analyzed, 15,250 (38.9%) received ACEI/ARB and 24,001 (61.1%) received other antihypertensive therapy at year 1 after transplantation. The mean duration of follow-up was 5.8 years. During years 2 to 10 after transplantation, cardiovascular death occurred in 918 patients (cumulative incidence=4.7%) with a functioning graft. The rate of cardiovascular death was similar in patients who received ACEI/ARB therapy or other antihypertensive treatment overall and in subpopulations of patients who were considered by the transplant center to be at an increased cardiovascular risk, had no pretransplant risk factors, were aged 60 years and older, were treated for diabetes at year 1, or had serum creatinine of 130 μmol/L or higher at year 1. Multivariable Cox regression analysis confirmed that treatment with ACEI/ARB did not confer a beneficial effect beyond that conferred by other antihypertensive treatments on the cumulative incidence of cardiovascular death during years 2 to 10 (hazard ratio=1.1, P=0.24).

CONCLUSIONS

This large-scale retrospective analysis of prospectively collected data shows that the rate of cardiovascular death in kidney transplant recipients receiving ACEI/ARB or other antihypertensive medications is virtually identical.

Prevalence and management of post-transplant anemia in long-term follow-up of Chinese kidney transplant recipients: a single-center report

BACKGROUND

Post-transplant anemia (PTA) has long been a less-recognized complication in kidney transplant recipients, and its prevalence also tends to be underestimated. This study sought to evaluate the prevalence, management, and risk factors of PTA from a group of long-term follow-up Chinese kidney transplant recipients.

METHODS

One hundred and fifty-four adult kidney transplant recipients were followed up at Fuzhou General Hospital, China, and retrospectively studied.

RESULTS

PTA prevalence at transplant and at 5-yearly time points after transplantation were 45.5%, 10.7%, 9.6%, 14.8%, 13.5%, and 19.6%, respectively. Overall, 38.3% of patients had been anemic at least once during the follow-up period, and 42% of these patients had recurrent anemia. Correlation analysis indicated that hemoglobin levels were associated with graft function. No correlations between anemia and age, gender, immunosuppressive regimens, or antihypertensive agents were observed. Binary logistic regression analysis suggested that serum creatinine and blood urea nitrogen were associated with the diagnosis of anemia at 1 year post-transplant. At 5 years post-transplant, only serum creatinine concentrations correlated with anemia. Although iron drugs are frequently used, erythropoietin was rarely administered in those anemic patients suffering poor graft function that necessitated such therapies.

CONCLUSIONS

The prevalence of PTA is noticeably high, and impaired kidney graft function seemed to be the major risk factor for anemia. There is an urgent need to improve current PTA management and to establish modified guidelines for this common complication in kidney transplant recipients.

Anemia control in renal transplant recipients receiving continuous erythropoietin receptor activator (C.E.R.A.) treatment: the AnemiaTrans Study

INTRODUCTION

Continuous erythropoietin receptor activator (C.E.R.A.) effectively enables anemia control in patients with chronic kidney disease, but little information is available in renal transplant recipients. The authors aimed to evaluate the effect of C.E.R.A. under clinical practice conditions on anemia control in renal transplant recipients.

METHODS

This was a multicenter, retrospective, observational study carried out in adult renal transplant patients in the immediate posttransplant period and at late posttransplant period receiving C.E.R.A. in clinical practice. Patients' data were retrieved from their medical charts at baseline and months 1, 3, and 6.

RESULTS

A total of 318 evaluable patients were enrolled into the study: 32 in the immediate posttransplant period and 286 at late posttransplant period (erythropoiesis-stimulating agent [ESA]-naïve, n = 44; converting from other ESAs, n = 242). Patients in the immediate posttransplant period experienced a significant increase in hemoglobin (Hb) levels from baseline to month 1 (9.9±1.5 g/dL vs. 11.5±1.4 g/dL; P< 0.001). ESA-naïve patients showed increasing mean Hb levels from baseline to month 6 (10.1±0.7 g/dL vs. 11.7±1.0 g/dL; P < 0.001) and 94.7% achieved Hb ≥11 g/dL during the study. In patients converted from other ESAs, the percentage of patients with Hb between 11-13 g/dL was maintained from baseline to month 6 with no significant differences (61.0% vs. 62.4%). Mean monthly doses of C.E.R.A. at baseline were 134.4±56.4 μg, 81.3±28.1 μg, and 93.0±44.2 μg in immediate posttransplant, ESA-naïve, and converted patients, respectively. C.E.R.A. was well tolerated.

CONCLUSION

C.E.R.A. enables anemia control in renal transplant recipients, allowing target Hb levels to be achieved and maintained with doses even below those described in the Summary of Product Characteristics.

Serum erythropoietin level and mortality in kidney transplant recipients

BACKGROUND AND OBJECTIVES

Posttransplant anemia is frequently reported in kidney transplant recipients and is associated with worsened patient survival. Similar to high erythropoiesis-stimulating agent requirements, resistance to endogenous erythropoietin may be associated with worse clinical outcomes in patients with ESRD. We examined the association between serum erythropoietin levels and mortality among kidney transplant recipients.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We collected sociodemographic, clinical, medical, and transplant history and laboratory data at baseline in 886 prevalent kidney transplant recipients (mean age 51 ± 13 [SD] years, 60% men, 21% diabetics). A solid-phase chemiluminescent immunometric assay was used to measure serum erythropoietin. Cox proportional hazards regression was used to model the association between baseline serum erythropoietin levels and all-cause mortality risk.

RESULTS

During the median 39-month follow-up, 99 subjects died. The median serum erythropoietin level was 10.85 U/L and hemoglobin was 137 ± 16 g/L. Mortality rates were significantly higher in patients with higher erythropoietin levels (crude mortality rates in the highest to lowest erythropoietin tertiles were 51.7, 35.5, and 24.0 per 1000 patient-years, respectively [P = 0.008]). In unadjusted and also in adjusted Cox models each SD higher serum erythropoietin level significantly predicted all-cause mortality: HR(1SD increase) 1.22 and 1.28, respectively. In adjusted Cox models each SD higher serum erythropoietin/blood hemoglobin ratio also significantly predicted all-cause mortality: HR(1SD increase) 1.32. Serum erythropoietin predicted mortality in all analyzed subgroups.

CONCLUSIONS

In this sample of prevalent kidney transplant recipients, higher serum erythropoietin levels were associated with increased mortality.

[Cytopenias following kidney transplantation]

Cytopenias frequently occur during the first months after solid organ transplantation. Many mechanisms are involved but drugs toxicity and infections are the major causes of cytopenias. Anemia is also related with chronic kidney graft dysfunction. Several drugs are pointed out but antithymocyte globulin, antiproliferative drugs and antiviral drugs are mainly responsible for cytopenias. Infectious causes are mainly viral and can rarely induce macrophage activation syndromes. Passenger lymphocyte syndrome is only described after ABO incompatible transplantations. Thrombotic microangiopathies are frequent and multifactorial (antibody mediated rejection, calcineurine inhibitors toxicity, infections, initial nephropathy recurrence). Cytopenias following transplantation increase the risk of infectious disease by neutropenia and generally lead to an immunosuppressive therapy reduction. It seems to increase the risk of rejection when the baseline immunosuppressive level is not further restored.

Hematologic Disorders after Solid Organ Transplantation

The evaluation of hematologic disorders after solid organ transplantation (SOT) must take into account issues unique to the post-transplant setting that influence the development of anemia and single or multi-lineage cytopenias. Attention to the time of onset of cytopenia(s) is important, because the disorders of passenger lymphocyte syndrome, transplant-related thrombotic microangiopathy, hemophagocytic syndrome, and graft-versus-host disease typically occur during the first few months after SOT, and post-transplant lymphoproliferative disorder usually occurs within the first year. Drug-related anemia and cytopenia(s) occur due to a variety of mechanisms, including drug-induced hemolysis and marrow suppression and perturbation of T-cell subsets by the immunosuppressive agents, leading to immune dysregulation and autoimmunity. Viral infections can cause direct suppression of hematopoiesis, and a variety of opportunistic infections can precipitate acquired hemophagocytic syndrome, a frequently lethal systemic inflammatory disorder. Early investigation of pancytopenia by bone marrow biopsy is warranted, because it is often the presenting symptom of one or multiple life-threatening pathologies after SOT, such as graft-versus host disease, post-transplant lymphoproliferative disorder, hemophagocytic syndrome, or severe opportunistic infections, and these entities may have a better prognosis if early interventions are undertaken.

Association between the malnutrition-inflammation score and post-transplant anaemia

BACKGROUND

Post-transplant anaemia (PTA) is common and is associated with adverse consequences. The protein-energy wasting (PEW) syndrome is associated with erythropoietin resistance in patients on maintenance dialysis. We assessed the association between PEW and PTA in a large prevalent cohort of stable kidney-transplanted patients.

METHODS

Data from 942 prevalent kidney-transplanted patients were analysed. Socio-demographic parameters, laboratory results, transplantation-related data and medication were obtained from the charts. Biomarkers reflecting nutritional status and inflammation [serum leptin, albumin, interleukin-6 (IL-6), tumour necrosis factor-α (TNF-α) and C-reactive protein] were measured. Anthropometric measures and the malnutrition-inflammation score (MIS) were also tabulated. Anaemia was defined according to the guidelines of the American Society of Transplantation.

RESULTS

Mean age was 51 ± 13 years, 57% were males and 22% had diabetes. The prevalence of PTA was 33%. The haemoglobin (Hb) level significantly and negatively correlated with the MIS (rho = - 0.316), marginally with serum TNF-α (rho = - 0.079) and serum IL-6 (rho = - 0.075) and positively with serum transferrin (r = 0.298), serum albumin (r = 0.274), abdominal circumference (r = 0.254) and serum leptin (rho = - 0.152), P < 0.05 for all. In a multivariable linear regression model, MIS was independently associated with Hb (beta = - 0.118, P = 0.004) in patients with estimated glomerular filtration rate (eGFR) lower than or equal to 60 mL/min/1.73 m(2), but not in patients with higher eGFR.

CONCLUSIONS

The MIS is independently associated with PTA in the kidney-transplanted population with eGFR lower than or equal to 60 mL/min/1.73 m(2).

Calcium, phosphate and parathyroid metabolism in kidney transplanted patients

INTRODUCTION

Impaired kidney function is common in kidney-transplanted patients and complications of chronic kidney disease (CKD), such as mineral and bone disorders (MBD) are also prevalent in this population. Similarly to other stages of CKD, increasing evidence supports the association between MBD and cardiovascular risk after kidney transplantation as well. Still, little is known about the prevalence, clinical correlates of MBD and its management in transplanted patients. In this study, we aimed to examine the characteristics of MBD and its associations with clinical parameters in a large prevalent cohort of patients after kidney transplantation.

METHODS

Nine hundred and ninety stable patients followed at a single kidney transplant outpatient clinic were included in the study. Detailed medical history, demographic data and routine laboratory results, including Ca, P and intact PTH were collected. Estimated GFR was calculated using the abbreviated MDRD formula, patients were stratified into three groups based on eGFR. Target levels for Ca, P and iPTH were based on CKD stages according to the NKF-K/DOQI guidelines. Standard statistical procedures, binomial and multinomial regressions were used in the analysis.

RESULTS

The mean age was 51 years, 57% were males and 21% were diabetic, with 72 months (median) post-transplantation. Most of the patients were in CKD stage 3. Serum phosphorus showed strong negative correlation with graft function in CKD stages 4-5 (r = -0.633, P < 0.001). Hyperphosphatemia was independently associated with the time spent on dialysis before transplantation, serum iPTH and CKD stages 4-5. iPTH showed negative correlation with eGFR in CKD stages 3-5 (rho = -0.289, P < 0.001) and weak positive correlation with time spent on dialysis prior to transplant (rho = 0.114, P < 0.001). Both hyperparathyroidism (42%) and relative hypoparathyroidism (15%) were frequent. The prescription of P-binders (6%) and vitamin D analogs (33%) was sporadic.

CONCLUSION

Disturbances of bone and mineral metabolism after transplantation are prevalent and are strongly correlated with the kidney function, similarly to non-transplanted CKD patients. MBD in this population is not adequately managed.