Creatinine clearance and proteinuria as early markers of kidney graft survival

Introduction

In patients who receive a kidney transplant from expanded criteria donors (ECDs), few studies are available concerning the relation between the clinical characteristics, pretransplant biopsies, and graft outcomes.

Aim

To identify early clinical markers predicting worse graft survival in recipients of kidneys from ECDs.

Materials and methods

Between 1999 and 2006, we performed a prospective, observational study in 180 recipients of kidney grafts from ECDs that had undergone a preoperative biopsy to evaluate viability. The patients received immunosuppression with basiliximab, late introduction of tacrolimus, mycophenolate mofetil, and steroids. Data were gathered on demographic and posttransplantation clinical characteristics at 1, 3, 6, and 9 months, including estimates of proteinuria and of the glomerular filtration rate using the Modification of Diet in Renal Disease (MDRD) formula.

Results

The mean age of the donors was 63.54 years and of the recipients, 58.38 years. A creatinine clearance below the median (40 mL/min, interquartile range 32-50 mL/min) in the first posttransplant year was significantly associated with worse death-censored graft survival (log-rank 14.22, P < .0001). A proteinuria value above the median (100 mg/24 h, interquartile range 40-275 mg/24 h) at 1 year posttransplant significantly reduced the death-censored graft survival (log-rank 14.3, P < .0001). Multivariate Cox analysis showed that a creatinine clearance < 40 mL/min in the first year (hazardsratio [HR] 5.7, 95% Confidence Interval [CI] 1.62-20.37; P = .007) and proteinuria at 1 year greater tan 100 mg/24 h (HR 8.3, 95% CI 2.15-32.06; P = .002) were independent risk factors for death-censored graft loss after adjusting for donor age and acute rejection episodes.

Conclusions

Limited renal function and/or low proteinuria at 1 year posttransplant were associated with worse kidney graft survival among recipients of kidneys from ECDS.     

Clinical outcome of renal transplantation in end-stage renal disease patients with positive pretransplantation hepatitis B surface antigen

Background

Renal transplantation (RTx) is the best therapeutic modality for patient suffering from end-stage renal disease (ESRD) with positive pretransplantation hepatitis B surface antigen (HbsAg). We report 11 years of single-center experience on RTx vis-à-vis patient/graft survival, graft function in terms of serum creatinine (SCr), and rejection episodes in 35 ESRD patients with pretransplantation HbsAg positivity.

Patients and Methods

Thirty-five ESRD patients with pretransplantation HbsAg positivity underwent RTx at our center between 2000 and 2010. Mean recipient age was 36.06 ± 12.22 years; 30 were males and 5 were females. Mean donor age was 43.51 ± 13.63 years; 13 were males and 22 were females. The majority of donors were parents (31.42%) and spouses (22.85%). Mean HLA match was 2 ± 1.37. The most common recipient diseases leading to ESRD were chronic glomerulonephritis (51%) and diabetes (17.5%). Posttransplantation immunosuppression consisted of a calcineurin inhibitor-based regimen.

Results

Over mean follow-up of 6.16 ± 3.69 years, patient and graft survival rates were 71.42% and 71.42%, respectively, with mean SCr of 1.92 ± 0.62 mg% with 20% biopsy-proven acute rejection episodes. In total, 10 (28.57%) patients were lost, mainly to infections.

Conclusion

RTx for ESRD with pretransplantation HbsAg positivity has acceptable graft function and patient/graft survival over 11 years follow-up and should be encouraged.     

Cause of Death in Multiorgan Donors and Its Relation to the Function of Transplanted Kidneys

Background

Brain death is an important variable contributing to donor-specific kidney damage. Poor kidney performance posttransplantation may be related to the cause of death of the donor.

Objective

To assess the influence of cause of death in multiorgan donors on the function of transplanted kidneys.

Material and Methods

Standard criteria for the brain stem death protocol were applied in 146 potential heart donors included in the study. Conventional supportive management consisted of mechanical ventilation to achieve normocapnia, rewarming, and fluid and electrolyte replacement. Dopamine infusion not exceeding 10 μg/kg/min and desaminovasopressin were titrated to predetermined mean arterial pressure (MAP). In renal allograft recipients (n = 232), kidney function was monitored using serial serum creatinine concentrations on days 1, 2, 3, 7, 14, 30, and 90 posttransplantation. The relation between donor cause of death (injury, bleeding, or other cause) and recipient serum creatinine concentration was analyzed in the postoperative period.

Results

Significantly greater serum creatinine concentrations were observed up to 14 days posttransplantation in recipients of a kidney from a donor who died of any cause other than injury. Recipients of a kidney from a donor who died of bleeding exhibited significantly greater serum creatinine concentrations at 30 days posttransplantation.

Conclusions

A cause of death other than injury or bleeding in a multiorgan donor is predictive of worse kidney graft function in the first 14 days posttransplantation. Intracranial bleeding in a multiorgan donor is predictive of worse kidney graft function in the early period posttransplantation.     

Use of simulect can reduce the incidence of acute rejection and demonstrates with superior 3-year patient and graft survival rates in renal transplantation

Background

Acute rejection is a major cause of graft loss in renal transplantation. Because the highest risk for acute rejection is in the first month posttransplantation, improved prophylaxis could be most beneficial in this period. Simulect administration provides 30 to 45 days of immunoprophylaxis against acute rejection during the critical period after transplantation.

Objectives

We sought to assess the incidence of acute rejection episodes and the safety and tolerability of Simulect plus Neoral immunosuppression. Patient and graft survival rates up to 3 years posttransplantation were evaluated.

Method

Forty-one transplant recipients received Simulect by intravenous infusion of an initial 20-mg dose on the day of renal transplantation and a second 20-mg dose on day 4 posttransplant. All renal recipients received immunosuppression with Neoral and steroid.

Results

There were eight cases (19.5%) of acute rejection within 1 year. The rejection episodes were easily reversed with steroid pulse therapy in seven patients except for graft loss. The 1-, 2-, and 3-year graft survival rates were 95%, 93%, and 88%, respectively. Overall, the 3-year patient survival rate was 100%.

Conclusions

Simulect in combination with Neoral and steroid-reduced the incidence of acute rejection without an increase in adverse events. The low incidence and severity of acute rejection may have led to the superior 3-year patient and graft survival rates in renal transplantation.     

Extended-release tacrolimus therapy in de novo kidney transplant recipients: single-center experience

Background

Available data for extended-release tacrolimus (Tac) except in clinical trials are limited.

Objective

To describe our initial experience with once-daily Tac in combination with corticosteroids and mycophenolate mofetil therapy in patients undergoing de novo renal transplantation.

Patients and Methods

In this retrospective, observational, single-center study, data were obtained for 49 adult recipients treated with extended-release Tac and 30 patients treated with standard-release Tac (control group). Mean (SD) follow-up in the 2 groups was 3.5 (2.5) months and 4.0 (2.6) months, respectively. The primary characteristics were comparable between the groups.

Results

The acute rejection rate in the extended-release group was 10%, and 13% in the standard-release group. Patient and graft survival rates were 98% and 96% vs 100% and 90%, respectively. Renal function in the 2 groups was comparable: serum creatinine concentration 1.3 (0.2) mg/dL vs 1.45 (0.4) mg/dL. At day 14 posttransplantation, Tac doses were 0.17 mg/kg/d vs 0.14 mg/kg/d, and blood concentrations were 9.0 ng/mL vs 14.0 ng/mL. In recipients older than 60 years, lower dosages of Tac resulted in blood concentrations similar to those in younger patients, with less variation in dosage.

Conclusions

Short-term experience with extended-release Tac therapy in de novo renal recipients confirms its efficacy and safety. Adjusting blood concentrations in the immediate posttransplantation period is less difficult with extended-release Tac compared with the twice-daily formulation.     

The prognostic value of pre-implantation graft biopsy on the outcomes of renal transplantations

Introduction

The pre-implantation graft biopsy is an important tool for the selection of donors, providing objective information about graft function outcomes. The degree of histological lesions is related to the incidence of delayed graft function (DGF) and long-term survival of the graft.

Materials and Methods

We analyzed 30 graft biopsy specimens by a semi-quantitative evaluation of chronic lesions. We evaluated the clinical characteristics of recipients, the presence of DGF, and the renal function in the immediate posttransplantation period, as well as month 3 and month 6 after transplantation.

Results

Histological evaluation showed glomerulosclerosis score 0 in 77% versus score of 1 in 23%; fibrosis score 0 in 46.5% versus score 1 in 46.5% and score 2 in 7%; tubular atrophy score 0 in 53.5% versus score 1 in 36.5% and score 2 in 10%; vascular score 0 in 17% versus score 1 in 50% and score 2 in 33%. Approximately 33% of patients displayed DGF and 13% acute rejection episodes. There was a positive correlation between the presence of interstitial fibrosis and serum creatinine values at 3 (P = .01) and 6 months (P = .02). No correlation was observed between graft function and the presence of tubular atrophy, glomerulosclerosis, and vascular changes.

Conclusion

We observed that a large number of graft biopsy specimens (83%) displayed vascular changes related to the age of the donor. Only a minor degree of interstitial fibrosis, was related to better graft function. The presence of tubular atrophy, vascular changes, and glomerulosclerosis showed no impact on short-term graft function.     

Change in Serum Lipid Peroxide as an Oxidative Stress Marker and Its Effects on Kidney Function After Successful Kidney Transplantation

Background

Reactive oxygen species are believed to be responsible for organ injury after reperfusion. We evaluated serial changes in lipid peroxide (LPO) as an oxidative stress marker after kidney transplantation and investigated its effects on graft function.

Methods

Fifty-nine kidney transplant recipients were enrolled between September 2006 and March 2009. The control group consisted of kidney donors (n = 40). Serum LPO concentrations were measured by a thiobarbituric acid reaction. The serum creatinine concentration and estimated glomerular filtration rate (eGFR) were used to evaluate graft function. Blood samples were obtained preoperatively, on postoperative day (POD) 5, and at 1 year posttransplantation. The median concentration of LPO on POD 5 was used as a cut-off.

Results

The mean preoperative LPO concentration was greater than the control group. The mean LPO concentration on POD 5 was increased compared with the preoperative level. However, the mean LPO concentration at 1 year was significantly decreased compared with the preoperative day, but greater than the control group. On POD 5, the mean serum creatinine concentration in the low LPO group was lower than that in the high LPO group. The mean eGFR in the low LPO group was significantly higher than that in the high LPO group. There was no difference in mean serum creatinine concentrations and eGFR at 1 year between the groups.

Conclusion

Oxidative stress showed a significant impact on graft function in the immediate posttransplant period.     

Serum flow cytometric c1q binding antibody analysis of renal recipients with low levels of sensitization

Aim

Patients displaying flow cytometric crossmatch results within the grey zone of positivity are hard to evaluate, especially if they are undergoing their first transplantation. For these patients assays of donor-specific anti-HLA (human leukocyte antigen) antibodies with complement-fixing properties to cause cell lysis are important for antibody-mediated rejection and graft failure. The aim of this study was to detect the relevance of serum C1q-binding antibodies detected in renal recipients with grey zone crossmatch reactivity who were considered to show low levels of sensitization against their potential donors.

Method

This study includes 114 patients who were admitted for their first renal transplantation between September 2009 and August 2011, including 33 subjects considered by flow cytometric cross-match to be the sensitized group, whereas the remaining 81 recipients had negative results. We analyzed the accumulation of serum the immunoglobulin (Ig)G bound C1q on HLA-coated flowcytometric panel reactive antibody (FlowPRA) beads. The serum samples were retrospectively analyzed with [C1q]FlowPRA (HLA class I and II), which were collected during the pretransplantation period every 6 months and every week posttransplantation within the first month and every 3 months thereafter. All serum samples were analyzed for the presence of anti-FlowPRA IgG alloantibody. We compared the C1q FlowPRA-positive and-negative groups for the number of posttransplantation days that the serum creatinine level was below <2 mg/dL as a metric of graft function.

Results

With a mean follow-up of 492 ± 84 days, there was a significant difference between flow cytometric crossmatch results and creatinine decrease rate (P = .02). The serum creatinine decrease rates of the 9 C1q-positive versus the 15 C1q-negative subjects showed significant difference (P < .05).

Conclusion

C1q-binding antibody analysis shows the presence of serum antibodies capable of complement binding and antibody-mediated rejection, which could be useful to assess rejection risk among the “grey zone” of renal recipients with low levels of sensitization against their donors.     

Donor-recipient age difference and graft survival in living donor kidney transplantation

Background

In paired living kidney exchange donation from an old donor to a young recipient, it may be argued that elderly donors provide an inferior quality kidney. However, the impact of donors older than recipients on transplant outcomes remains unclear.

Methods

We retrospectively reviewed the charts of primary living kidney transplantation patients who were divided into two groups based on the age difference between donor and recipient (recipient age subtracted from donor age, donor-recipient < 20 vs ≥ 20). The donor-recipient age difference < 20 group comprised 75 and donor-recipient age difference ≥ 20 group, 25 subjects. Outcome measures included serum creatinine, acute rejection episodes as well as graft and patient survivals at 1 and 5 years after transplantation.

Results

The mean donor age difference cohorts of < 20 and ≥ 20 years showed donor ages of 33 ± 8 and 54 ± 8 years, respectively. The mean recipient age in both groups averaged under 40 years. The acute rejection rate within the first year posttransplantation was greater among age difference ≥ 20 years. The mean serum creatinine values of the donor-recipient age difference < 20 group was lower than the ≥20 years group at 1 and 5 years posttransplant. The 1-year difference was associated with an increased creatinine value at 5 years. However, death-censored graft survival of the age difference of the ≥ 20 years group was not different (hazard ratio [HR] = 0.1, 95% confidence interval [CI] = 0.01-1.37, P = .08). Patient survival of the age difference ≥ 20 years group showed no difference compared with the age difference < 20 years group (HR = 0.25, 95% CI = 0.01-6.35, P = .4).

Conclusion

Although the cohort of a donor-young recipient age difference ≥ 20 years showed a greater risk of an acute rejection episode early posttransplantation, it did not affect graft or patient survivals. When considering paired kidney donation, older age donors should not necessarily be limited.     

Risk of cardiovascular disease associated with refractory hypertension in renal transplant recipients

Background

Hypertension is common after renal transplantation, affecting as many as 80% of recipients. It is generally accepted that hypertension is associated with poor graft survival and reduced life expectancy because of increased cardiovascular risk factors. The prevalence of refractory hypertension in renal transplant recipients is unknown, and could be associated with a poor prognosis.

Objective

To investigate the effects of refractory hypertension on cardiovascular disease (CVD) after renal transplantation in 486 patients with grafts functioning for longer than 1 year.

Patients and Methods

Patients were classified into 2 groups: (1) 57 with refractory hypertension, that is, systolic blood pressure 130 mm Hg or greater or diastolic blood pressure 80 mm Hg or greater, and receiving treatment with at least 3 drugs, one of which was a diuretic; and (2) the remaining 429 patients. Patient and graft survival, and posttransplantation CVD were analyzed.

Results

Refractory hypertension was associated with male sex (82.5% vs 66.5% [P < .01]), poor renal function (mean [SD] serum creatinine concentration 2.2 [1.2] mg/dL vs 1.6 [0.6] mg/dL; Modification of Diet in Renal Disease score 39.2 [20.0] mL/min/1.73 m² vs 49.2 [18.0] mL/min/1.73 m² [P = .000]; and steroid therapy (94.7% vs 79.0% [P = .001]). In the group with refractory hypertension, 5-year patient and graft survival rates were lower, and the incidence of posttransplantation CVD was greater (relative risk, 1.7; 95% confidence interval, 1.05-2.18; P = .03).

Conclusion

Refractory hypertension is an independent risk factor for increased cardiovascular morbidity and mortality in renal transplant recipients.     

Multivariate Analysis of Risk Factors for Early Loss of Pancreas Grafts Among Simultaneous Pancreas-Kidney Transplants

To evaluate the risk factors for pancreas graft loss within 3 months postoperatively among 170 simultaneous pancreas-kidney transplantation (SPKT) we examined 38 variables.

Methods

Twenty-two variables were related to recipients; 12 to donors and 4 to the surgical procedure. In addition the latest follow-up dates as well as the transplant and/or death dates. Independent variables were examined with reference to the dependent pancreatic loss variable, excluding losses owing to deaths. Variables with statistical significance were analyzed to predict early graft loss.

Results

Univariate analyses determined the following significant variables: kidney cold ischemia time, older donors, non-white donors, death cause related to vascular disease, wound infection, and length of extended hospitalization. However, multivariate analysis showed that only donor age and kidney cold ischemia time were significant predictors for early pancreastic graft loss.

Conclusion

Donor age and kidney cold ischemia time were independently related to pancreatic loss after SPKT within 3 months posttransplantation.     

Conversion to Tacrolimus Extended-Release Formulation: Short-term Clinical Results

Objective

To determine the short-term clinical results of conversion of treatment from tacrolimus twice daily (BID TAC) to the extended-release formulation (OD TAC), milligram for milligram, and whether such conversion is safe in stable kidney transplant recipients.

Patients and Methods

The study included 38 kidney transplant recipients (median [SD] age, 54.3 [14.4] years) with stable renal function (mean [SD] serum creatinine concentration 1.29 [0.38] mg/dL). Posttransplantation follow-up was 3.4 (3.1) years (range, 4-168 months). All patients had been receiving BID TAC (2.45 [1.52] mg/d) when treatment was converted to OD TAC, milligram for milligram. Follow-up including clinical evaluation and laboratory tests was at 7, 21, and 90 days postconversion.

Results

No significant differences were observed during follow-up in serum creatinine concentration, blood glucose level, hemoglobin level, or proteinuria. There were no episodes of acute rejection. No de novo posttransplantation diabetes mellitus was diagnosed; patients with diabetes required similar dosage of hypoglycemia treatment. Arterial pressure remained stable without changes in antihypertension treatment. Tacrolimus doses were not modified (2.45 [1.52] mg/d at baseline vs 2.45 [1.67] mg/d at 3 months postconversion; however, tacrolimus concentration decreased significantly (7.6 [1.8] ng/mL at baseline vs 6.42 [1.13] ng/mL at 3 months postconversion. Reduction in tacrolimus concentration was more remarkable in patients receiving a dose of less than 0.025 mg/kg/d.

Conclusions

Conversion from BID TAC to OD TAC, milligram for milligram, is clinically safe; however, monitoring of tacrolimus concentration in patients receiving low dosage is mandatory to prevent subtherapeutic levels.     

1,25-Dihydroxyvitamin D Deficiency Predicts Poorer Outcome After Renal Transplantation

Objective

To assess 1,25-dihydroxyvitamin D status and the effect of vitamin concentration on transplantation outcome in renal allograft recipients.

Patients and Methods

Ninety patients underwent renal transplantation between 2002 and 2005. All received alfacalcidol supplementation before surgery. 1,25-Dihydroxyvitamin D concentration was determined on day 3 posttransplantation and at 1-, 6-, 12-, 18-, and 24-month follow-up.

Results

Severe 1,25-dihydroxyvitamin D deficiency was noted in 83% of patients immediately posttransplantation. From 1 to 12 months thereafter, concentrations increased almost 3-fold, and remained constant to 24 months. In 50% of patients, the 1,25-dihydroxyvitamin D concentration reached a concentration of more than 30 pg/mL, similar to that in healthy volunteers; in the other 50%, the concentration reached 17.2 pg/mL. A high incidence of delayed graft function was observed in patients with 1,25-dihydroxyvitamin D deficiency (44% vs 6%). There was a negative correlation between the initial 1,25-dihydroxyvitamin D and serum creatinine concentrations at day 3 and month 6 (P < .03). Similarly, the 1,25-dihydroxyvitamin D concentration at 1 month was negatively correlated with creatinine concentration at months 1 through 24 (P < .01). Poor outcome was observed primarily in patients with 1,25-dihydroxyvitamin D deficiency; 2 patients developed cancer, 5 grafts were lost, and 4 patients died of cardiovascular events.

Conclusions

1,25-Dihydroxyvitamin D deficiency is highly prevalent in renal allograft recipients. Patients with 1,25-dihydroxyvitamin D deficiency are at greater risk of delayed graft function, and the graft is more likely to be lost. These findings suggest the necessity of adequate vitamin D supplementation both before and after transplantation.     

Graft infection in kidney recipients and its relation to transplanted kidney function

Introduction

Following kidney transplantation, septic complications are the leading causes of therapeutic failure including recipient death or graft removal. The serum creatinine level is one of the earliest metrics of kidney metabolic function. We examined the influence of graft infection on serum creatinine levels in kidney recipients.

Study design

We analyzed the function of 220 kidneys transplanted in nine centers in Poland. The kidneys were recovered from 146 multiorgan donors. Donor urea and creatinine levels were within the normal range. We investigated the influence of perioperative graft infection incidence on recipient creatinine levels at 1, 2, 3, 7, 14, 30, 90, and 180 days after kidney transplantation. The association of the serum creatinine level with categorical variables was assessed using either Student t test analysis of variance and multivariate techniques. In all analyses P < .05 indicated statistical significance.

Results

There were 25 graft infections revealing a significant relationship with increased recipient serum creatinine level after kidney transplantation (P = .003). Multivariate analysis confirmed the impact of infection.

Conclusion

Perioperative kidney graft infection influenced graft funtion in the early and late periods post-transplantation.     

Early postoperative spectral Doppler parameters of renal transplants: the effect of donor and recipient factors

Background

The objective of this study was to explore the donor and recipient factors related to the spectral Doppler parameters of the transplant kidney in the early posttransplantation period.

Methods

This retrospective study included 76 patients who underwent renal transplantation assessed using Doppler ultrasonography (US) on the first postoperative day. We compared spectral Doppler parameters (peak systolic velocity [PSV] and resistive index [RI]) of the segmental artery of the transplant kidney according to the type of renal transplant, level of serum creatinine (SCr) of donor prior to organ donation, and donor/recipient age.

Results

RI was significantly higher in deceased-donor kidney transplantation (DDKT) as compared with living-donor kidney transplantation (LDKT; 0.73 ± 0.10 vs 0.66 ± 0.11; P = .007). In the DDKT recipients, multivariate analysis showed donor SCr was the only factor affecting PSV (P = .023), whereas recipient age was the only factor affecting RI (P = .035). In the LDKT recipients, multivariate analysis showed recipient age was the only factor affecting both PSV (P = .009) and RI (P = .018).

Conclusion

Spectral Doppler parameters in the early posttransplantation period are related to the type of renal transplant, donor renal function, and recipient age. These factors should be taken into consideration when interpreting the results of spectral Doppler US.     

Hyperuricemia after renal transplantation

Background

Hyperuricemia is a common complication after kidney transplantation, and may adversely affect graft survival.

Objective

To assess the prevalence of and predictors for development of hyperuricemia after renal transplantation.

Materials and Methods

Hyperuricemia was defined as a serum uric acid concentration of at least 7.0 mg/dL in men and 6.0 mg/dL in women. From March 2008 to May 2010, uric acid concentration was measured in 12,767 blood samples from 2961 adult renal transplant recipients (64% male and 36% female patients).

Results

Hyperuricemia was observed in 1553 patients (52.4%). The disorder frequently occurred in women (P = .003) and in patients with impaired renal graft function (P = .00). After adjustment for sex, serum creatinine concentration, diabetes mellitus, cyclosporine concentration, and dyslipidemia, only female sex (P = .03) and renal allograft dysfunction (P = .05) were associated with hyperuricemia after kidney transplantation.

Conclusion

Hyperuricemia is a common complication after kidney transplantation, and renal allograft insufficiency predisposes to higher uric acid concentration.     

Is it safe to use a kidney from an expanded criteria donor?

Background

The use of expanded criteria donor (ECD) kidneys has been encouraged to enlarge the donor pools due to the shortage of donors. However, a major concern with ECD kidneys is poor long-term graft survival. The objective of this study was to determine whether ECD kidneys had a negative impact on graft survival.

Methods

We analyzed all deceased donor renal transplantations at our center from September 1995 to December 2009.

Results

ECD donors show characteristics, such as comparatively older age, a history of hypertension and diabetes, the use of norepinephrine, high serum creatinine levels and deceased donor scores, and decreased albumin levels and estimated glomerular filtration rates. However, the occurrence of delayed graft function and primary nonfunction among ECD grafts was comparable to those of standard criteria donor (SCD) grafts. Graft survival was not significantly different between the two groups. Only serum creatinine levels at 3, 6, and 9 months after transplantation were lower in the ECD than the SCD group. Multivariate analysis identified longer hospital stay after transplantation, delayed graft function, and acute rejection episodes as independent predictors of poor graft survival.

Conclusion

Graft survival of ECD kidney was comparable to that of SCD kidneys. We observed that donor factors prior to procurement were not risk factors for graft failure.     

First Year Renal Function as a Predictor of Kidney Allograft Outcome

Background

Several factors are known to have detrimental effects on kidney allograft function in the first year posttransplantation, which has been reported to be an important factor influencing long-term graft survival.

Objectives

The objectives of this study were to evaluate risk factors for lower estimated glomerular filtration rate (eGFR) at 3 and 12 months posttransplantation and analyze the influence of first year allograft function on graft and patient survivals.

Patients

We performed a retrospective review of the clinical data from 433 cadaveric donor kidney transplantations in adults performed in our unit from May 1989 to May 2007.

Results

Donor female gender and nontraumatic cause of death, panel-reactive antibody (PRA) titer ≥50%, acute rejection episodes, and delayed graft function (DGF) were significant risk factors for a decreased eGFR at one year posttransplantation. Recipient and donor age showed negative correlations with eGFR at 3 and 12 months. A logistic regression model showed acute rejection episodes, DGF, donor age ≥55 years, donor female gender, and nontraumatic cause of donor death to be independent adverse risk factors for eGFR <60 mL/min at 3 and 12 months. Lower eGFRs at 3 and 12 months were associated with poorer allograft survival when data were censored for death with a functioning graft and patient survival. Multivariate analysis revealed that PRA titer ≥50%, acute rejection episodes, and eGFR <30mL/min at 12 months had adverse effects on allograft survival.

Conclusion

Several factors influence kidney allograft function in the first year after transplantation. Kidney allograft function at 12 months predicted long-term graft survival.     

Comparison of paired exchange kidney transplantations with living related kidney transplantations

Objective

Paired-exchange kidney transplantation (PETx) gains an importance because it is difficult to find suitable organs. The aim of this study was to compare biochemical and clinical parameters of PETx with those of living-related kidney transplantation (LRTx).

Method

The 57 PETx included 18 female and 39 male recipients among 1081 LRTx in 360 females and 721 males (N = 1138) whose operations were performed between November 21, 2008, and March 1, 2011. These two groups were compared for graft and patient survival, rejections, serum creatinine levels, glomerular filtration rates (GFRs), and other biochemical parameters.

Results

The PETx patients were older than the LRTx patients (45.4 ± 13.2 years versus 40.9 ± 13.5 years; P = .014). HLA mismatch was higher in the PETx group (4.7 ± 0.7 versus 3.56 ± 1.6; P = .000). First- and second-year serum creatinine and GFR values were similar between the two groups. Acute rejection episodes (PETx: 13/57; LRTx: 226/1081, P = .925), patient loss (0/57 versus 34/1081; P = .174) and graft loss (1/57 versus 55/1081; P = .257) were similar between the two groups.

Conclusion

Our study showed similar biochemical and clinical findings of PETx versus LRTx over 2 years posttransplantation.     

Clinical manifestations of hypercalcemia and hypophosphatemia after kidney transplantation

Introduction

Abnormalities of calcium and phosphorus metabolism in end-stage renal disease patients can persist after transplantation. We investigated their natural courses after transplantation, their risk factors for posttransplantation hypercalcemia and hypophosphatemia, and their impacts on allograft outcomes.

Methods

We retrospectively analyzed a total of 490 adult patients who underwent kidney transplantations between 2000 and 2009.

Results

The serum calcium continued to increase, and reaching a plateau at around 3 months after transplantation. Thereafter it decreased, reaching a stable level by 2 years. Forty-four patients (9.0%) displayed hypercalcemia within 1 year; it persisted longer than that in 23 subjects (4.7%). Both longer dialysis duration (odds ratio [OR] 1.423; 95% confidence interval [CI], 1.192-1.699) and high intact serum parathyroid hormone (iPTH) level before transplantation (OR 1.002; 95% CI, 1.000-1.003) increased the risk for posttransplantation hypercalcemia. After a significant decrease during the first week, the serum phosphorus level increased, becoming stable between 1 and 6 months after transplantation. Hypophsphatemia occurred in 379 patients (77.3%) with 336 patients displaying hypophosphatemia without hypercalcemia. However, neither hypercalcemia nor hypophosphatemia influenced graft outcomes. Eight patients underwent pretransplantation parathyroidectomy, whereas 4 patients underwent posttransplantation parathyroidectomy. Neither group of patients experienced posttransplantation hypercalcemia.

Conclusions

Both hypercalcemia and hypophosphatemia are common after renal transplantation, especially among patients with a long history of dialysis before transplantation. Strict control of hyperparathyroidism including parathyroidectomy before transplantation may be the appropriate approach to these abnormalities.