Anemia After Renal Transplantation

Treatment Options for Anemia in Kidney Transplant Patients: A Review

Anemia is common after kidney transplantation. The etiology may be multifactorial, such as causes of anemia in the general population and causes that are unique to the kidney transplant setting. Posttransplant anemia, particularly when severe, may be associated with adverse effects such as graft failure, mortality, and a decline in kidney function. After careful investigation, that is, having excluded or treated reversible causes of anemia, treatment of anemia in patients with a kidney transplant is based on iron supplementation or erythropoiesis-stimulating agents (ESA), although there are no specific guidelines on anemia management in this patient population. Iron therapy is often needed, but optimal and safe iron-deficiency management strategies remain to be defined. Evidence suggests that ESAs are safe and potentially associated with favorable outcomes. Better graft function has been reported with ESA use targeting hemoglobin levels higher than those recommended in the general population with chronic kidney disease and with no apparent increased risk of cardiovascular events. These results require further investigation. Data on the use of hypoxia-inducible factor inhibitors are limited. Prevention and treatment of anemia in kidney transplantation can improve patients' quality of life, life expectancy, allograft function, and survival.

Impact of iron status on kidney outcomes in kidney transplant recipients

Iron plays an important role in hemodynamics and the immunity, independent of anemia. Since dynamic changes occur in iron storage after kidney transplantation (KT), we investigated the association between iron status and kidney outcomes in KT patients. We analyzed data from the KoreaN cohort study for Outcome in patients With KT (KNOW-KT). The iron status was classified into three groups based on ferritin or transferrin saturation (TSAT) levels one year after KT, with reference ranges of 20‒35% and 100‒300 ng/mL for TSAT and ferritin, respectively. The primary outcome was the composite outcome, which consisted of death, graft failure, and an estimated glomerular filtration rate decline ≥ 50%. In total, 895 patients were included in the final analysis. During a median follow-up of 5.8 years, the primary outcome occurred in 94 patients (19.8/1000 person-years). TSAT levels decreased one year after KT and thereafter gradually increased, whereas ferritin levels were maintained at decreased levels. The adjusted hazard ratios (95% confidence intervals) for the composite outcome were 1.67 (1.00-2.77) and 1.20 (0.60-2.40) in the TSAT > 35% and ferritin > 300 ng/mL groups, respectively. High iron status with high TSAT levels increases the risk of graft failure or kidney functional deterioration after KT.

The current therapeutic approach for anaemia after kidney transplant

PURPOSE OF REVIEW

Anaemia after kidney transplantation is a common finding with no uniform management guideline. Most approaches are derived from the chronic kidney disease (CKD) population. Recent advances for the treatment of anaemia in patients with CKD/End stage renal disease include hypoxia-inducible factor-prolyl hydroxylase inhibitor (HIF-PHi), a novel class of oral erythropoietin-stimulating agents (ESAs). We present relevant studies of HIF-PHi in the transplant population and its implications on the management of posttransplant anaemia.

RECENT FINDINGS

Data on HIF-PHi use in the kidney transplant population are promising. Limited data demonstrate a significant increase in haemoglobin, with a comparable safety profile to epoetin. Reported adverse effects include overcorrection and low iron stores.

SUMMARY

Current therapeutic approaches to anaemia in the kidney transplant population is mostly derived from the CKD population. More studies are needed on HIF-Phi, a novel class of ESAs that has thus far demonstrated promise in the kidney transplant population.

Influence of Pretransplant Factors on Posttransplant Anemia Recovery Rate in Primary Deceased Donor Kidney Transplant Recipients

OBJECTIVES

Our objective was to evaluate the influence of pretransplant risk factors on posttransplant anemia recovery.

MATERIALS AND METHODS

This single-center observational retrospective study included 80 deceased donor kidney transplant recipients who had been followed up to 16 months after kidney transplant. Time point of posttransplant anemia recovery was considered the time when hemoglobin of 11.0 g/dL was achieved and maintained for 3 consecutive monthly visits. We collected donor/transplant characteristics (age, sex, hypertension history, cause of death, donor kidney function, expanded criteria donor status, deceased donor score, HLA mismatch, and cold ischemia time) and recipient data (pretransplant hemoglobin, parathyroid hormone, kidney graft function, delayed graft function, acute rejection, infections, surgical bleeding, posttransplant parathyroid hormone, iron stores, and C-reactive protein and tacrolimus levels). We used univariate and multivariate Cox proportional hazards analyses and Kaplan-Meier plots to determine associations between variables and posttransplant anemia recovery rate. P < .05 was considered significant.

RESULTS

We identified 62 deceased donors (33 male; mean age 50 ± 15.1 years) and 80 kidney transplant recipients (52 male; mean age 47.0 ± 10.6 years). Mean pretransplant hemoglobin was 11.4 ± 1.5 g/dL. Donor age, deceased donor score, pretransplant parathyroid hormone, posttransplant transferrin saturation (all P < .05), and tacrolimus level (P < .01) were significantly related to posttransplant anemia recovery. Kaplan-Meier curve identified that recipients of deceased donors below 60 years old achieved hemoglobin of 11.0 g/dL more frequently and earlier than recipients of deceased donors above 60 years old (P < .05).

CONCLUSIONS

Deceased donor age, deceased donor score, pretransplant serum parathyroid hormone, posttransplant transferrin saturation, and tacrolimus level were significantly associated with posttransplant anemia recovery rate in deceased donor kidney transplant recipients. Anemia recovery was more frequent and earlier in recipients of deceased donors below 60 years than in recipients of donors 60 years old and above.

Anemia and Erythrocytes: Behavior and Prevalence 1 Year After Kidney Transplant

INTRODUCTION

Renal transplantation presents multiple complications after its completion, some of them related to the behavior of hemoglobin levels. The objective of this study is to determine the behavior and prevalence of anemia and erythrocytosis in the first year after renal transplantation.

MATERIAL AND METHODS

A retrospective, observational study was conducted of a cohort of patients of the 21st Century National Medical Center in Mexico of transplants performed from January 1, 2013 to December 31, 2017. A total of 649 met the inclusion criteria. Pre-transplant hemoglobin (Hb) levels were determined, as well as levels 1 month, 3, 6, 9, and 12 months after transplantation, and the prevalence of anemia and erythrocytosis was determined in each month. Descriptive analysis was performed with measures of central tendency and measures of dispersion. The statistical program SPSS version 25 was used.

RESULTS

The mean pre-transplant Hb was 10.69 g/dL (standard deviation [SD] 2.04). One year after the renal transplant, Hb averaged 14.45 g/dL (SD 2.30), which meant an increase over the first year after renal transplantation of 3.76 g/dL. Pre-transplant anemia occurred in 73.1% of patients, and erythrocytosis in 0.1%; 12.9% of patients and 5.9% in erythrocytosis continued with anemia for a year.

CONCLUSIONS

Renal transplantation allows Hb levels to recover in a multifactorial way; however, the persistence of anemia and erythrocytes creates a study challenge in any transplant unit, due to their prevalence of 12.9 and 5.9% respectively.

The interaction between post-transplant anemia and allograft function in kidney transplantation: The Japan Academic Consortium of Kidney Transplantation-II study

BACKGROUND

The interaction between post-transplant anemia (PTA) and allograft function in kidney transplantation has not been evaluated directly. PTA, defined by WHO/AST criteria, was investigated in 1307 adult kidney transplant recipients between 2000 and 2015 (median follow-up, 7 years).

METHODS

We investigated the impact of hemoglobin (Hb) on graft failure (non-censored for death) and their interactions, time-dependent Cox model, and subgroup analysis were used.

RESULTS

PTA prevalence was 43.6% at 7 years and varied according to allograft function, recipient sex, and follow-up period. Decreased Hb considering the time-varying effect was associated with an increased risk of graft failure (hazard ratio = 1.83, 95% CI 1.66-2.02, P < 0.001). In subgroup analysis, allograft function (post-transplant time-averaged estimated glomerular filtration rate and cut point: 45 mL/min/1.73 m²) had significant interaction (P = 0.032). The 7-year graft failure rate in recipients with PTA and high eGFR was 7.7% (HR 1.52, 95% CI 1.25-1.84), whereas in those with PTA and low eGFR was 19.9% (HR 2.00, 95% CI 1.74-2.31).

CONCLUSIONS

The unfavorable impact of PTA was significantly enhanced by low allograft function. PTA is likely to be associated with graft failure due to interaction with allograft function. Therefore, we should consider both Hb level and allograft function while determining the treatment strategy.

Post renal transplant anemia: severity, causes and their association with graft and patient survival

Background

Post transplantation anemia (PTA) is common among kidney transplant patients. PTA is associated with increased graft loss and in most studies with increased mortality. However, the effect of the severity of anemia on this associations was not thoroughly evaluated.

Methods

Patients who underwent kidney transplantation in Rabin Medical Center (RMC) were included in the study. Data were collected during the years 2002–2016. Anemia was defined as hemoglobin (Hb) level less than 12 g/dL in women and less than 13 g/dL in men, in accordance with World Health Organization (WHO) criteria. Severe anemia was defined as hemoglobin lower than 11 g/dL. Primary outcome was a composite of patient and graft survival. We used univariate and multivariate models to evaluate association between severity and specific causes of anemia with the outcomes. As the risk associated with anemia changed over time we analyzed the risk separately for the early and the late period (before and after 1251 days).

Results

Our cohort included 1139 patients, 412 (36.2%) of which had PTA and 134 (11.7%) had severe anemia. On multivariable analysis, severe anemia was highly associated with the primary outcome at the early period (HR 6.26, 95% CI 3.74–10.5, p < 0.001). Anemia due to either AKI & acute rejection (11.9% of patients) or infection (16.7%), were associated with primary outcome at the early period (HR 9.32, 95% CI 5.3–26.41, p < 0.001 and HR 3.99, 95% CI 2.01–7.95, p < 0.001, respectively). There was non-significant trend for association between anemia due to Nutritional deficiencies (29.1%) and this outcome (HR 3.07, 95% CI 0.93–10.17, p = 0.067).

Conclusion

PTA is associated with graft loss and mortality especially during the first three years. Anemia severity affects this association. An anemia workup is recommended for PTA.

Electronic supplementary material

The online version of this article (10.1186/s12882-019-1244-y) contains supplementary material, which is available to authorized users.

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.

Retrospective analysis of perioperative transfusion requirements in living donor renal transplantation

BACKGROUND

Extensive bleeding in solid organ transplantation is a major challenge faced by transplant surgeons. Our aim was to audit the peri-operative transfusion requirements in our patients.

MATERIALS AND METHODS

A retrospective analysis of living donor renal transplant surgeries performed from 1st May 2014 to 31st December 2014 was done. The blood/blood component usage during the peri-operative period was obtained. Univariate analysis was performed and the significant factors identified were further analyzed through multivariate regression analysis.

RESULTS

A total of 510 patients (398 males: 78%, and 112 females: 22%) ranging from 18 to 77 years in age were included in the study. Of these, 269 (52.7%) patients were not transfused, while 241 (47.3%) patients received a total of 845 units of blood/blood components. The mean pre-operative hemoglobin in the transfused group was 8.7g/dl while in the non-transfused group it was 10.3g/dl. Leukoreduced packed red blood cell (PRBC) was the major blood component transfused during the peri-operative period. Multivariate regression analysis revealed that pre-operative hemoglobin was a major predictor of intra-operative PRBC transfusion (p = <0.001). Average post-operative length of stay (PLOS) was 10 ± 6 days. There was no significant difference in the PLOS between the transfused and non-transfused groups of patients; however, a statistical significant increase in utilization for both PRBC (p = 0.044) and fresh frozen plasma (p = 0.002) was observed with increased PLOS.

CONCLUSION

Nearly 47.3% of patients undergoing living donor renal transplant received transfusion. PRBC was the most common product transfused and pre-operative hemoglobin was identified as strong predictor of blood consumption.

Treatment With Darbepoetin During the First Year After Renal Transplantation: The Starting Point

INTRODUCTION

Multiple factors are associated with post-transplantation anemia, and renal function is the main factor. The aims of this study were to compare the evolution of hemoglobin in the first year post-transplantation according to darbepoetin (DA) treatment, and factors related to it, to evaluate the difference between earlier versus delayed treatment, and to describe the dose change pattern.

PATIENTS AND METHODS

We describe a retrospective study of cohorts in 462 transplant recipients (2004-2011). The variables reported were from donor, transplantation recipient, and DA treatment.

RESULTS

In this study, 67.5% of patients were treated with DA, 32.5% were not. The comparison of hemoglobin in both groups during the first year showed a similar evolution with significant differences between consecutive measures until the second trimester. The hemoglobin of the treated group was significantly lower. The evolution of renal function was not different. Multivariate analysis related DA treatment to delayed graft function (DGF) and albuminuria in the first year. Patients with early versus delayed DA introduction did not show a difference regarding length of treatment, but the total dose in the delayed introduction was lower. The evolution of creatinine and hemoglobin was similar in both groups.

CONCLUSION

The introduction of DA was related to DGF and albuminuria. The delayed introduction of DA meant the following: less total dose than earlier introduction, no difference in length of treatment, and a similar evolution in hemoglobin and renal function in both groups. The lack of guidelines about DA treatment in renal transplantation makes it difficult to establish a pattern of dose adjustment.

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.

The pre-transplant anemic condition is independent of long-term outcome in living-related kidney transplantation

The relationship between pre-transplant Hemoglobin (Hb) concentration and long-term outcome of living-related kidney transplantation is far from well addressed. A retrospective cohort study was conducted by reviewing the medical profile of the patients who received living-related kidney transplantations at our center from January 2006 to January 2013. Patients were divided into two groups: high Hb group (≥10 g/dL) and low Hb group (<10 g/dL). Cox regression model was utilized to analyze the effect of pre-transplant hemoglobin concentration on the patient and graft survival. About 422 patients were of Hb level <10 g/dL (78.30 ± 14.18 g/dL), 280 were >10 g/dL (116.2 ± 14.43 g/dL) (p < 0.001). In a follow-up of 35.34 ± 18.12 months, we did not find any difference in serum creatinine between the two groups. Low Hb concentration is not associated with increased risk of developing DGF (HR = 1.186, 95% CI: 0.53-2.654), acute rejection (HR = 1.338, 95% CI: 0.919-1.947), overall infection (HR = 1.263, 95% CI: 0.847-1.885) nor perioperational infection (HR = 1.019, 95% CI: 0.513-2.026). Though we detected a trend that low Hb level group were of higher incidence of patient death and graft failure, the two groups did not differ significantly (2.38% vs. 0.71%, p = 0.096; and 4.04% vs. 2.14%, p = 0.165, respectively). Cox regression model revealed that pre-transplant Hb level <10 g/dL was independent of increased overall mortality (HR = 3.379; 95% CI: 0.706-17.172) and increased death censored allograft failure risk (HR = 1.556; 95% CI: 0.595-4.069). Pre-transplant Hb concentration <10 g/dL is independent of poor long-term outcome of living-related kidney transplantation.

The impact of post-transplant hemoglobin level on renal allograft outcome

BACKGROUND

Anemia is a common complication of chronic renal disease and renal transplantation. Early post-transplant anemia is the consequence of blood loss, immunosuppressant therapy, and failure to produce sufficient erythropoietin. Late post-transplant anemia has been attributed to drug therapy, renal dysfunction, and infection. The effect of post-transplant anemia on renal allograft survival and acute rejection rates is not established. The aim of this study was to examine the impact of post-transplant anemia on renal function and allograft outcomes.

MATERIALS AND METHODS

We included 411 patients who underwent living or deceased donor renal transplantations in our center from April 1990 to March 2010. The patients were divided into 2 groups according to their postoperative hemoglobin level at 1 month: anemic group (<12.0 g/dL in men, <11.0 g/dL in women) and nonanemic group (≥ 12.0 g/dL in men, ≥ 11.0 g/dL in women). The outcome measures included postoperative serum creatinine levels at 12 and 36 months, acute and chronic rejection rates, as well as long-term graft survival.

RESULTS

The acute and chronic rejection rates were significantly higher in the anemic group: 28.1% versus 19.7% (P = .000) and 24.1% versus 19.7% (P = .027), respectively. Postoperative serum creatinine levels at 12 and 36 months were not significantly different in patients with functioning grafts regardless of their anemia status (P = .530 and P = .430, respectively). Graft survival was lower with anemia: 85.4% versus 93.8% at 5 years, and 74.8% versus 83.5% at 10 years (P = .040).

CONCLUSIONS

Post-transplant anemia was associated with poorer renal function at 12 months, higher acute rejection rates, and worse long-term renal allograft outcomes compared with subjects displaying normal hemoglobin levels.

Renal function is independently associated with red cell distribution width in kidney transplant recipients: a potential new auxiliary parameter for the clinical evaluation of patients with chronic kidney disease

Red cell distribution width (RDW), a measure of heterogeneity in the size of circulating erythrocytes, reportedly predicts mortality. Similarly to RDW, impaired renal function is also associated with inflammation and protein-energy wasting. This study assessed if renal function is associated with RDW independent of relevant confounders in stable kidney transplant recipients. We examined the association between RDW and estimated glomerular filtration rate (eGFR) in a cohort of 723 prevalent kidney transplanted recipients who were not receiving erythropoietin-stimulating agents. Associations were examined in regression models adjusted for age, sex, comorbidity, blood haemoglobin, iron indices, markers of nutritional status and inflammation, markers of bone and mineral metabolism and the use of immune suppressants. Lower eGFR was significantly associated with higher RDW (r = -0·382, P < 0·001). This association remained highly significant even after multivariate adjustments where 10 ml/min decrease in the eGFR was significantly associated with an increase of the RDW values (B10 ml/min decrease  =  0·078; 95% confidence interval: 0·044-0·111). The results were consistent in subgroups of patients with different levels of haemoglobin, chronic kidney disease status and various markers of inflammation and iron status. Lower eGFR is associated with higher RDW, independent of comorbidity, iron deficiency, inflammation and nutritional status in kidney transplant recipients.

Anemia in living donor kidney transplantation

BACKGROUND

We evaluated the prevalence of pretransplantation and posttransplantation anemia and its effect on serum creatinine levels among living donor kidney transplant recipients.

METHODS

We reviewed retrospectively 170 adult patients who underwent living donor kidney transplantation between 1994 and 2009. We defined anemia as hemoglobin (Hb) ≤12 g/dL for women and ≤13 g/dL for men with severe anemia as Hb <11 g/dL for both men and women (World Health Organization criteria). Patients were also categorized according to Hb levels less than or greater than 10 g/dL for correlation with recipient serum creatinine levels at months 1, 3, 6, and 12.

RESULTS

Mean recipient and donor ages were 33 ± 10 and 45 ± 12 years, respectively. Mean cold ischemia time was 76 ± 43 minutes. At the time of transplantation, anemia and severe anemia prevalences were 86.7% and 58.8%, respectively. Anemia was observed in 64 patients (42.1%) at posttransplantation month 3. Pretransplantation severe anemia was a good predictor of both Hb levels and anemia presence posttransplantation. Pretransplantation anemia and severe anemia caused greater requirements for posttransplantation blood transfusions (P < .05). Younger age and female gender were significant risk factors for severe anemia pretransplantation. There was a significant correlation between posttransplantation Hb levels and serum creatinine levels at 12 month (P = .01). Recipient female gender and longer hospital stay were significant risk factors for both anemia and severe anemia posttransplantation. Higher recipient weight and history of acute rejection episode were also significant for posttransplantation severe anemia.

CONCLUSION

This study indicated that successful kidney transplantation had a positive effect on Hb levels. Posttransplantation anemia predicted worse graft function in the first month after transplantation.

Post-transplant anemia and associated risk factors: the impact of steroid-free therapy

CONTEXT AND OBJECTIVE

The prevalence of post-renal transplant anemia (PTA) reported in the literature is variable and several factors contribute towards its pathophysiology. This study aimed to investigate the prevalence of PTA, its associated risk factors and the impact of therapy without steroids.

DESIGN AND SETTING

Retrospective cohort study in a renal transplantation unit at a tertiary hospital.

METHODS

Anemia was defined as hemoglobin (Hb) < 12 g/dl in female adult recipients and < 13 g/dl in males. Donor and recipient age and gender, type of donor, creatinine, delayed graft function, acute rejection, use of angiotensin-converting enzyme inhibitors (ACEI) or angiotensin receptor blockers (ARB) and therapy without steroids were investigated as risk factors for PTA through multivariate logistical regression analysis.

RESULTS

Evaluations were performed on 258 recipients (mean age: 38.8 years; 60.5% males; 35.7% did not receive steroids). Anemia was diagnosed in 38% of the patients (at the sixth month, M6), 28% (M12), 32% (M24) and 45% (at last follow up). Donor age > 50 years was associated with greater risks of PTA at M6 (odds ratio (OR) = 4.68) and M24 (OR = 6.57), as well as with therapy without steroids at M6 (OR = 2.96). Delayed graft function was independently associated with PTA at M6 (OR = 3.66) and M12 (OR = 2.85).

CONCLUSION

The lowest prevalence of PTA was observed between M9 and M24 after renal transplantation. Delayed graft function, donor age and therapy without steroids were the most important factors associated with PTA.

Treatment of anemia with erythropoietin-stimulating agents in kidney transplant recipients and chronic kidney disease-another drawback of immunosuppression?

Anemia is more prevalent in allograft recipients compared with glomerular filtration rate (GFR) matched patients with chronic kidney diseases. There is a paucity of data concerning the correction of anemia in the posttransplant period with erythropoietin-stimulating agents (ESA). The aim of this study was to compare the iron status, kidney function, inflammatory state, use of drugs affecting erythropoiesis (immunosuppressants ACEi/ARB) and correction of anemia using ESA in a chronic kidney disease (CKD) population versus kidney transplant recipients. We included 67 patients treated with ESA including 17 after kidney transplantation. CKD Patients with native kidneys were significantly older than allograft recipients (mean age 69 versus 51 years; P < .001, and despite similar serum creatinine and iron parameters showed an estimated lower GFR (19 mL/min versus 23 mL/min; P < .05). Median time of ESA therapy was similar among patients with native kidney CKD versus kidney recipients, but they achieved a significantly higher hemoglobin (11.04 versus 10.36 g/dL; P < .05). There was no difference between patients administered or not a mammalian target of rapamycin antagonist. None of the patients with native kidney CKD received immunosuppressive therapy, but they were prescribed ACEi more often than kidney recipients. The higher degree of anemia in kidney allograft recipient is the most probably attributed to the use of immunosuppressive drugs, despite their better kidney function and comparable iron status. This study suggested that higher doses of ESA should be employed to anemia in kidney transplant recipients.

Systematic review of hepatocellular carcinoma mortality rates among hepatitis B virus-infected renal transplant recipients, with supplemental analyses of liver failure and all-cause mortality

OBJECTIVES

The purpose of this review was to compare the mortality rates for hepatocellular carcinoma (HCC) among hepatitis B surface antigen (HBsAg)-seropositive renal transplant (RT) patients versus HBsAg-seropositive persons of the general population.

METHODS

A comprehensive search was performed to identify cohort studies of HBsAg-seropositive RT patients with at least 4 years of follow-up. Data were analyzed as outlined below. HCC was a rare event in regions of low and intermediate seroprevalence of HBsAg. Subsequently, studies from low and intermediate seroprevalence areas were analyzed separately from those of high seroprevalence areas.

RESULTS

Thirty-one retrospective studies that followed 1277 seropositive RT patients were identified for inclusion. The studies were pooled and compared to four different general population studies that included 12558 seropositive persons using Poisson methods. The mortality rate of HCC was increased in low and intermediate seroprevalence areas (RR 7.67, 95% confidence interval (CI) 3.93-15.0; RR 9.92, 95% CI 5.38-18.3). In high seroprevalence areas, the mortality rate of HCC was increased compared to one population study, but not another (RR 2.76, 95% CI 1.64-4.63; RR 1.02, 95% CI 0.61-1.69).

CONCLUSIONS

Mortality due to HCC was increased in low and intermediate seroprevalence areas, but the evidence was inconclusive for high seroprevalence areas.

The Janus faces of ESAs: caveat Chimaera!

Patients with chronic kidney disease (CKD) have a Janus quality as they look back whence they came in developing CKD and, in some cases, also look forwards to a potential kidney transplant with the attendant promise of improvement in quality and often quantity of life. Making the most of this often unique opportunity is key-maximising the chance that the engraftment starts as a success, and then later, preserving good kidney transplant function for as long as possible. Two recently published, independently conceived and executed studies are relevant to both aspects of this quest and thus to all kidney transplant recipients (KTRs). Both trials also simultaneously stoke and quench the continuing, heated debates over target haemoglobin (Hb) levels, and the use of erythropoiesis-stimulating agents (ESAs), in CKD patients. One study--of acute, high-dose ESA administration--adds to the plethora of adverse safety signals swirling around the use of ESAs while surprisingly also showing renal function benefits at 12 months. The other study features chronic lower-dose ESA use in stable KTRs with anaemia and impaired renal function and not only purports to show a salutary effect on 2-year renal function outcomes (and thus reducing "return to dialysis" rates), but also rebuts the now widely accepted current notion that by chronic use of ESAs to target full Hb correction/higher Hb values in anaemic CKD patients, we are potentially causing harm.

Anemia and erythrocytosis in patients after kidney transplantation

Anemia is a highly prevalent disorder in recipients of renal allografts. Despite its frequent occurrence, there is still uncertainty with regard to treatment targets and treatment options. This includes questions on appropriate iron management, the choice and dosage of erythropoietin stimulating agents, criteria for the timing of treatment initiation and the targeted hemoglobin values. The review summarizes available data on recent therapeutic strategies for post transplant anemia, as well as for post transplant erythrocytosis, another hematological disorder, that has decreased in recent years.

Risk factors for chronic anemia in pediatric orthotopic liver transplantation: analysis of data from the SPLIT registry

Risk factors for chronic anemia in the post-transplant period have not been clearly delineated in pediatric liver transplant recipients. We analyzed data from children transplanted from 2000 to 2008 with at least two consecutive hemoglobin values from follow-up between six months and five yr post-transplant. A multivariate model was derived to determine independent risk factors associated with chronic anemia. Of 1026 children in this analysis, 242 (23.6%) were found to have chronic anemia. On multivariate analysis, GI bleeding (OR 11.83 [2.08-67.49], p = 0.0054), presence of leukopenia (OR 9.55 [95% CI 3.71-24.62], p < 0.0001), use of cyclosporine (OR 3.69, [95% CI 1.56-8.76], p = 0.0039) and corticosteroids (OR 2.90 [95% CI 1.94-4.33], p < 0.0001), and cGFR <90 mL/min/1.73 m(2) (OR 4.62 [95% CI 2.47-8.67], p < 0.0001) represented the most significant risk factors for chronic anemia. Use of antihypertensive medications (OR 1.89 [95% CI 1.23-2.91], p = 0.0039) was also significantly associated with a higher risk. In summary, chronic anemia is common in children following liver transplant. Our findings underscore the need to define the mechanisms by which these risk factors, some of which are modifiable, result in chronic anemia in pediatric liver transplant recipients.

Increasing levels of hemoglobin improve renal transplantation outcomes

INTRODUCTION

Several studies have reported various data on prevalence of posttransplant anemia (PTA). We have little information about its impact on long-term graft outcomes and few studies of the optimal hemoglobin (Hb) target in kidney transplantation.

METHODS

We examined retrospectively 144 kidney transplant recipients of mean age 44.4 ± 12.3 years and follow-up of 40.5 ± 4.6 months. Exclusion criteria were age below 18 years, multiorgan transplantation, and graft failure in the first year. Using simple and multiple linear regression models, we evaluated the potential prediction of a serum concentration of Hb at 1 year after renal transplantation on allograft outcome as measured by Δ% estimated glomerular filtration rate (eGFR), the difference between eGFR, measured with the Modification of Diet in Renal Disease (MDRD) formula, at the end of follow-up, and at 1 year. Multiple models were adjusted for recipient sex, recipient age, donor age, ESA therapy, acute rejection episodes (ARE), days of delayed graft function, human leukocyte antigen mismatches and cold ischemia time.

RESULTS

At 1 year after transplantation, the mean Hb level was 13.77 ± 1.87 g/dL in males and 12.52 ± 1.53 g/dL in females. The average eGFR at 1 year was 63.07 ± 25.88 mL/min. At the end of follow-up, the mean Δ% eGFR was -5.73% ± 27.30%. Blood concentration of Hb correlated with donor, recipient sex, ARE, and eGFR at 1 year. There was a close correlation between the Δ% Hb and eGFR upon univariate analysis and the multiple linear regression model. Hb was the only predictor of transplant outcome.

CONCLUSIONS

Many factors are involved in kidney allograft function. Among these, Hb is important. In this work we demonstrated that increasing levels of Hb at 1 year after transplantation seemed to predict better preservation of graft function, representing a marker of a good quality graft.

Proteinuria is a predictor of posttransplant anemia

INTRODUCTION

Posttransplant anemia (PTA) involves many factors. Although the link between the hemoglobin (Hb) levels and renal function is known, the relationship between proteinuria and PTA hemoglobin has not been widely explored. The aim of this study was to evaluate whether proteinuria was a predictor of anemia and whether erythropoietin-stimulating agent therapy was a protective factor for kidney damage among transplantation patients.

METHODS

We retrospectively examined 144 kidney transplant recipients of mean age 44.4 ± 12.3 years and a mean follow-up period of 40.5 ± 4.6 months. Exclusion criteria were age under 18 years, multiorgan transplantation, proteinuria at 6 months over 1.5 g/d, and transplant failure within the first year. Using regression models, we evaluated the potential predictive power of proteinuria at 6 months after renal transplantation for anemia as expressed by Hb levels at 1 year.

RESULTS

The frequency of patients with PTA was 38.89% at 1 year, 35.21% at 2 years, and 31.43% at 3 years. Variables with significant correlations with anemia upon univariate analysis were: proteinuria, donor age, acute rejection, estimated glomerular filtration rate, s-creatinine, and salbumin. Upon multivariate regression analysis 24-hour proteinuria and s-albumin remained independent predictors of 1-year PTA. Univariate analysis among the entire cohort showed a significant correlation between 1-year Hb and proteinuria/24 hours at 6 months (P=.007), an observation that was confirmed in the adjusted model along with recipient sex. Patients were then divided into two groups regarding treatment with erythropoiesis stimulating agents (ESA). Multivariate analysis showed that proteinuria (P=.005) was a predictor of Hb only among the group of patients who did no receive erythropoietin, whereas this relationship disappeared among the group treated with ESA.

CONCLUSIONS

These results showed that proteinuria at 6 months was a predictor of Hb levels at 1 year. Treatment of transplant patients with ESA may be a protective factor for renal endothelial damage expressed as proteinuria.

Mammalian target of rapamycin (mTOR) inhibitors: potential uses and a review of haematological adverse effects

Mammalian target of rapamycin (mTOR) inhibitors (mTORis) constitute a relatively new category of immunosuppressive and antineoplastic drugs. These share a unique mechanism of action that is focused on the inhibition of the mTOR. Their clinical applications have recently expanded significantly to cover a wide spectrum of immune and non-immune-mediated disorders, including, apart from solid organ transplantation, various solid organ and haematological malignancies, rheumatological and auto-immune diseases such as rheumatoid arthritis, systemic lupus erythematosus, fibrotic conditions, e.g. pulmonary and hepatic fibrosis, and even metabolic problems such as diabetes mellitus and obesity. The most challenging and frequent adverse effects of the mTORis are the haematological ones, especially anaemia, leukopenia and thrombocytopenia. A unique characteristic of mTORi-induced anaemia is concurrent marked microcytosis. Recently, mechanisms have been proposed to explain the microcytic appearance of this anaemia; these include globin production defect, erythropoietin resistance, chronic inflammation, dysregulation of cellular iron metabolism and hepcidin-mediated iron homeostasis interference. As the differential diagnosis of microcytic anaemia includes pure iron deficiency, functional iron deficiency and haemoglobinopathies, characterization of the anaemia requires significant investigation, time and costs. Therefore, understanding of the likely interaction between mTORis and patients is valuable in clinical practice. Moreover, this could expand the drugs' therapeutic applications to other disorders, and suggest novel targets for further research.

Mammalian target of rapamycin (mTOR) inhibitors: potential uses and a review of haematological adverse effects

Mammalian target of rapamycin (mTOR) inhibitors (mTORis) constitute a relatively new category of immunosuppressive and antineoplastic drugs. These share a unique mechanism of action that is focused on the inhibition of the mTOR. Their clinical applications have recently expanded significantly to cover a wide spectrum of immune and non-immune-mediated disorders, including, apart from solid organ transplantation, various solid organ and haematological malignancies, rheumatological and auto-immune diseases such as rheumatoid arthritis, systemic lupus erythematosus, fibrotic conditions, e.g. pulmonary and hepatic fibrosis, and even metabolic problems such as diabetes mellitus and obesity. The most challenging and frequent adverse effects of the mTORis are the haematological ones, especially anaemia, leukopenia and thrombocytopenia. A unique characteristic of mTORi-induced anaemia is concurrent marked microcytosis. Recently, mechanisms have been proposed to explain the microcytic appearance of this anaemia; these include globin production defect, erythropoietin resistance, chronic inflammation, dysregulation of cellular iron metabolism and hepcidin-mediated iron homeostasis interference. As the differential diagnosis of microcytic anaemia includes pure iron deficiency, functional iron deficiency and haemoglobinopathies, characterization of the anaemia requires significant investigation, time and costs. Therefore, understanding of the likely interaction between mTORis and patients is valuable in clinical practice. Moreover, this could expand the drugs' therapeutic applications to other disorders, and suggest novel targets for further research.

Risk factors for immediate anemia in renal transplant recipients: a single-center experience

BACKGROUND

Although endogenous erythropoietin secretion returns via the renal allograft a few hours following successful engraftment, anemia is a common early or late complication. In addition, anemia is a risk factor for ischemic heart disease and graft loss. We sought to determine risk factors for and the prevalence of severe anemia immediately posttransplantation (PTA).

METHODS

This cross-sectional retrospective study performed between 2006 and 2009 enrolled 864 adult subjects of mean age 40.7±13.8 (range=6-75) years. On the basis of The World Health Organization criteria, a hemoglobin (Hb) level less than 11 g/dL for men and less than 10 g/dL for women was defined as severe anemia.

RESULTS

Severe anemia occurred frequently (62.7%) among these patients whose most common underlying disease was hypertension 311 (58.2%). Their mean Hb level was 9.9±1.8 g/dL at the time of hospital discharge, namely, almost 2 weeks after transplantation. More than 90% (n=778) of subjects received a kidney from a living donor. Immediate severe anemia associated with delayed graft function (DGF; P=.01), antithymocyte globulin (ATG)/antilymphocyte globulin (ALG) administration (P=.000), acute rejection (P=.000), recipient gender (P=.000), cold ischemic time (P=.01), pretransplant Hb (P=.000), posttransplant creatinine (P=.001), and acute rejection episodes (P=.000). Upon logistic regression analysis donor age (P=.04, confidence interval [CI]=0.7-0.9), recipient female gender (P=.009, CI=0.08-0.7), and ATG/ALG use (P=.009, CI=1.7-43.4) showed significant effects to cause severe PTA.

CONCLUSION

Immediate anemia after renal transplantation is a consequence of poor renal function. In addition, ATG/ALG use and DGF can induce severe PTA, which may play roles in ischemic heart disease and graft loss.

Treatment of anemia with epoetin in kidney transplant recipients

The aim of this study was to analyze the prevalence and efficacy of renal anemia treated with epoetin in maintenance kidney transplant recipients in Slovenia. By the end of 2009, 107 out of 537 patients (19.9%) had been treated with epoetin. A cohort of 49 patients (45.8%) were analyzed in detail: 11 patients received epoetin alpha, 18 epoetin beta, 10 darbepoetin alpha, and 10 patients received methoxy polyethylene glycol-epoetin beta. The median epoetin dose was 0.36 µg/kg body weight per week. The median serum laboratory parameters were as follows: hemoglobin 120 g/L, hematocrit 0.36, ferritin 332 ng/mL, transferrin saturation 34%, serum creatinine 145 µmol/L, serum albumin 41 g/L, intact parathyroid hormone 79 ng/L, and C-reactive protein 3 mg/L. We concluded that the prevalence of renal anemia in kidney transplant recipients treated with epoetin was approximately 20%, and laboratory parameters suggested that the treatment of renal anemia in this study cohort was optimal.

Erythropoietin resistance as surrogate marker of graft and patient survival in renal transplantation: 3-year prospective multicenter study

BACKGROUND

Some transplant recipients demonstrate an inadequate response to erythropoiesis-stimulating agents, or so-called erythropoietin (Epo) resistance. The cause is multifactorial. Resistance to EPO may entail a poor prognosis for the graft and the patient, although results in the literature are inconsistent, and long-term follow-up is lacking.

OBJECTIVE

To evaluate whether the presence of Epo resistance at the beginning of the study was a predictive factor for graft and patient survival.

MATERIALS AND METHODS

From 482 renal transplant recipients (Kidney Disease Outcomes Quality Initiative stage 3-4T) receiving Epo-stimulating agents in the Anemia and Renal Transplantation in Spain study, 101 were selected for the present study. Erythropoietin resistance was defined as a ratio of weekly Epo dosage/hemoglobin concentration>486,94 U/g/dL with a hemoglobin/<11 g/dL. Darbepoetin dosage was calculated in Epo equivalent units, with a 1:200 conversion factor. Patients were grouped as Epo-resistant (ER+) or not Epo-resistant (ER-), to assess whether Epo resistance was predictive of patient and graft survival.

RESULTS

There were no differences in demographic data between the 2 groups except for a higher incidence of vascular, interstitial, and diabetes-related causes of chronic renal failure in the ER+ group. At 3 years posttransplantation, graft survival was 33% in the ER+ group vs 58% in the ER- group (P=.06), and patient survival was 52% in the ER+ group vs 88% in the ER- group (P=.008). Using a Cox regression model, at 3 years, the relative risk of graft failure was 1.96 in the ER+ group (95% CI, 0.93-3.12; P=.07), and of patient death was 3.9 (95% confidence interval, 1.30-11.63; P=.01).

CONCLUSION

Erythropoietin resistance is an independent risk factor for death after renal transplantation.

Cause of death with graft function among renal transplant recipients in an integrated healthcare system

BACKGROUND

Cardiovascular disease (CVD) is the leading cause of death in renal transplant recipients with a functioning allograft. Modification of CVD risk factors may, therefore, decrease overall mortality in this patient population. We studied renal transplant recipients within an integrated healthcare system (IHS) that uses case management and electronic health records to determine mortality from CVD.

METHODS

We retrospectively collected data on all renal transplant recipients over a 10-year period. The primary endpoint was death with graft function (DWGF). Cardiovascular events were used as secondary endpoints. We determined the cause of death and collected laboratory data. The data were analyzed using Student's t test for continuous data, chi square for categorical data, and multivariate logistic regression. Survival was determined using the Kaplan-Meier product-limit method.

RESULTS

Death from "other" causes accounted for 29%. This was followed by CVD (24%), infection (16%), and malignancy (12%). The most common "other" causes were diabetes mellitus and end-stage renal disease. Overall, lower hemoglobin, uncontrolled blood pressure, and lower albumin levels were associated with DWGF. There were 184 cardiovascular events in total. Low-density lipid levels were lower in the group with cardiovascular events and DWGF. The use of antihypertensive and antihyperlipidemic agents was similar between the two groups with the exception of diuretics, which were used more often in the DWGF group.

CONCLUSIONS

There was a low rate of DWGF because of CVD within this IHS. It is possible that coordinated care within an IHS leads to improved cardiovascular mortality.

Early risk factors for persistent anemia after kidney transplantation

STUDY OBJECTIVE

To identify predictors of persistent posttransplant anemia that appear within the first week after kidney transplantation in order to determine the high-risk patients who might receive the most benefit from erythropoiesis-stimulating agents.

STUDY DESIGN

Retrospective cohort study.

SETTING

University-affiliated hospital and outpatient clinic.

PATIENTS

One hundred sixty-four adult kidney transplant recipients (January 1, 2002-June 30, 2007) with anemia on posttransplant day 7 who were followed at the clinic for at least 2 months after transplantation.

MEASUREMENTS AND MAIN RESULTS

Data from deidentified electronic medical records of the kidney transplant recipients were collected and included demographic characteristics, primary cause of renal failure, pertinent laboratory data, and donor information. To detect early predictors of persistent anemia, patients with persistent posttransplant anemia, defined as a hemoglobin level below 11 g/dl for 2 months (day 60) after transplantation, were compared with those who had nonpersistent posttransplant anemia, defined as a hemoglobin level below 11 g/dl on day 7 but 11 g/dl or greater on day 60. Of the 164 patients classified as having anemia on posttransplant day 7, 39 (23.8%) had persistent posttransplant anemia on day 60. In univariate analyses, hemoglobin level of 9 g/dl or below on day 7, donor age younger than 10 years, and female sex were variables associated with increased risk of persistent posttransplant anemia. In a multivariate analysis, donor age younger than 10 years was the most significant predictor of persistent posttransplant anemia, followed by hemoglobin level of 9 g/dl or below.

CONCLUSION

Patients receiving transplants from donors younger than 10 years and those with hemoglobin levels of 9 g/dl or below on postoperative day 7 were found to be at highest risk for persistent posttransplant anemia and may receive the most benefit from early initiation of erythropoiesis-stimulating agent therapy. In most of the kidney transplant recipients, posttransplant anemia resolved without the use of these agents.

Primary care of the renal transplant patient

There has been a remarkable rise in the number of kidney transplant recipients (KTR) in the US over the last decade. Increasing use of potent immunosuppressants, which are also potentially diabetogenic and atherogenic, can result in worsening of pre-existing medical conditions as well as development of post-transplant disease. This, coupled with improving long-term survival, is putting tremendous pressure on transplant centers that were not designed to deliver primary care to KTR. Thus, increasing numbers of KTR will present to their primary care physicians (PCP) post-transplant for routine medical care. Similar to native chronic kidney disease patients, KTRs are vulnerable to cardiovascular disease as well as a host of other problems including bone disease, infections and malignancies. Deaths related to complications of cardiovascular disease and malignancies account for 60-65% of long-term mortality among KTRs. Guidelines from the National Kidney Foundation and the European Best Practice Guidelines Expert Group on the management of hypertension, dyslipidemia, smoking, diabetes and bone disease should be incorporated into the long-term care plan of the KTR to improve outcomes. A number of transplant centers do not supply PCPs with protocols and guidelines, making the task of the PCP more difficult. Despite this, PCPs are expected to continue to provide general preventive medicine, vaccinations and management of chronic medical problems. In this narrative review, we examine the common medical problems seen in KTR from the PCP's perspective. Medical management issues related to immunosuppressive medications are also briefly discussed.

The possible role of early post-transplant inflammation in later anemia in kidney transplant recipients

Delayed kidney graft function and acute rejection in the early post-transplant period affect both short and long-term allograft survival. Allograft rejection, as an inflammatory state, results in increased erythropoietin resistance, which leads to decreased haemoglobin (Hb) level. We conducted this study to evaluate whether inflammation in the early post-transplant period could predict later anemia.This is a retrospective cohort study based on the analysis of 64 existing clinical records.

PREDICTOR

White blood cells (WBC) count obtained by the end of the first week post-transplant (W1). Covariates: Donor's age, recipient's age and sex.

OUTCOME

Anemia identified at 12 months (M12) post engraftment. Median WBC count at W1 was 9,5 x103/microL (5th - 95th percentile 5,2 x103/microL -17,8 x103/microL). Mean Hb values at M12 were 129,9 +/- 20,3 g/L, in males 136,2 +/- 20,1 g/L and in females 119,4 +/- 16,2 g/L. The significant correlation was found between WBC at W1 and Hb at M12. Pearson coefficient of correlation r was -0,26, and 95% confidence interval (CI) for r was -0,47 to -0,015 (p=0,03). Univariate logistic regression showed significant association between WBC at W1 and Hb at M12 (OR 1,20; 95% CI 1,04 to 1,39, p=0,01). After the adjustment for donor's and recipient's age by transplantation and recipient's sex, multiple regression showed that WBC count remained predictive of anemia at M12 (OR 1,17; 95% CI 1,01 to 1,36, p=0,03). Early post-transplant inflammatory response predicts later anemia in kidney transplant recipients. An increase in WBC count in the first week post-transplant by 109/L increases the risk for anemia after twelve months by 17%.

Impact of very early high doses of recombinant erythropoietin on anemia and allograft function in de novo kidney-transplant patients

After kidney transplantation, occurrence of anemia in the early post-transplant period (<1 month) is high and arises out of issues that are multifactorial. We performed a retrospective single-center study to assess whether delivery of high doses of erythropoietin-stimulating agents (ESA) within the first week of kidney transplantation, translates at 1 month post-transplant, in to causing less anemia and whether it has an impact on allograft function. Ninety-nine patients were not given ESA (group I), whereas 82 were (250 IU/kg/week; group II). All patients had similar pretransplant and baseline (day 0) variables. Similar numbers of group II patients were still receiving ESA by day 14 (97.5%) and day 30 (89%). Respective figures for group I were 27% and 27%. Independent factors for anemia at 1 month post-transplant included: being male subject, treatment for hypertension at pretransplant, anemia at transplant, a higher mean corpuscular volume at transplant, and an induction therapy using antithymocyte globulins. Independent predictive factors for lower creatinine clearance included being female subjects, having a donor aged >50 years, being a recipient aged >50 years, not treated for hypertension at pretransplant, and no post-transplant ESA therapy. High doses of ESA within the first month of kidney transplantation have no impact on anemia or renal function by 1 month post-transplant.

Anemia identified one month after renal transplantation is predictive of anemia identified after twelve months

The aim of this study was to evaluate whether anemia identified earlier than 3 months postengraftment in modern era could be predictive of anemia at 12 months. Cross-sectional and cohort studies based on retrospective analysis of existing clinical records were performed. Data on recipient's age at transplantation, follow-up serum creatinine (SCR) and hemoglobin (Hb) on day 7 (D7), at month 1 (M1) and at month 3 (M3) postengraftment were collected. Outcome was anemia identified at 12 months (M12) postengraftment. There were 75 patients on D7, 74 at M1 and 61 at M3. Multiple linear regression model that included recipient's age at transplantation, Hb and creatinine on D7 and tested the risk for anemia at M12 retained only the age in the model, with the coefficient of 0,84 (P=0,001). The same model at M1 retained Hb and age, with the coefficients of 0,26 (P=0,03) and 0,81 (P=0,0002), respectively and at M3 it retained Hb and age, with the coefficients of 0,41 (P=0,004) and 0,70 (P=0,003), respectively. Anemia identified at M1 after renal transplantation is predictive of anemia at M12.

Anemia after kidney transplantation

Over the last years, the renal transplant community has shown a growing interest in the incomplete correction of anemia by the transplanted kidney. Between 25% and 30% of these patients will be anemic at some time after transplantation. In addition to impaired kidney function, other factors may also play a role in the pathogenesis of posttransplant anemia: immunosuppressive agents such as azathioprine, mycophenolate mofetil, and sirolimus; angiotensin-converting enzyme inhibitors and angiotensin-II receptor antagonists; impaired iron homeostasis; and donor and recipient age. There is a controversy on whether posttransplant anemia has the same negative effects on morbidity and mortality as in nontransplanted patients with chronic kidney disease and data on whether correction of anemia are beneficial or lacking. Anemia check-up should be part of the long-term follow-up of the renal transplant patients. Controlled trials should investigate the impact of a better control of anemia on the patient morbidity and outcome.

Posttransplant anemia: the role of sirolimus

Posttransplant anemia is a common problem that may hinder patients' quality of life. It occurs in 12 to 76% of patients, and is most common in the immediate posttransplant period. A variety of factors have been identified that increase the risk of posttransplant anemia, of which the level of renal function is most important. Sirolimus, a mammalian target of rapamycin inhibitor, has been implicated as playing a special role in posttransplant anemia. This review considers anemia associated with sirolimus, including its presentation, mechanisms, and management.