Pancreas Donor Hypernatremia: Is it Really a Risk Factor for Simultaneous Pancreas-kidney Transplantation?

INTRODUCTION

Solid organ donor hypernatremia has been classically reported to be a risk factor for cell lysis and graft damage. National criteria for pancreatic donation consider severe hypernatremia (sodium level more than 160 mEq/L) to be relative exclusion criteria. The aim of our study is to review the postoperative outcomes of our simultaneous pancreas-kidney transplantation (SPKT) sample in terms of pancreatic fistula, intra-abdominal abscesses, pancreatitis, pancreas graft thrombosis, early pancreatectomy, and reoperation rates regarding different ranges of donor sodium levels.

MATERIAL AND METHODS

We performed a retrospective analysis among 161 SPKTs performed in our center between the years 2001 and 2017. We compared the aforementioned postoperative variables in two situations: 1) Whether the donor pancreas sodium levels were inferior to 149 mEq/L, or equal to or greater than 150 mEq/L; and 2) If they had severe hypernatremia (considering sodium levels greater than or equal to 160 mEq/L as threshold) or not. To ensure the comparability of the groups, a second comparison was performed on new samples after using propensity score matching. A Student t test or Mann-Whitney U test was used for intergroup comparisons of quantitative variables where appropriate, whereas a χ² test or Fisher's exact test was used to compare categorical data.

RESULTS

No statistically significant differences were found between the groups that relate high donor serum sodium levels with the morbidity variables included in our study or with early pancreatic graft loss.

CONCLUSIONS

In our cohort, early postoperative main morbidity and pancreas graft loss of SPKT recipients do not differ significantly regarding donor serum sodium levels.

What Is the Influence of Both Risk Donor and Risk Receiver on Simultaneous Pancreas-Kidney Transplantation?

INTRODUCTION

Some factors affect the pancreas of a marginal donor, and although their influence on graft survival has been determined, there is an increasing consensus to accept marginal organs in a controlled manner to increase the pool of organs. Certain factors related to the recipient have also been proposed as having negative influence on graft prognosis. The objective of this study was to analyze the influence of these factors on the results of our simultaneous pancreas-kidney (SPK) transplantation series.

MATERIALS AND METHODS

Retrospective analysis of 126 SPK transplants. Donors and recipients were stratified in an optimal group (<2 expanded donor criteria) and a risk group (≥2 criteria). A pancreatic graft survival analysis was performed using a Kaplan-Meier test and log-rank test. Prognostic variables on graft survival were studied by Cox regression. Postoperative complications (graded by Clavien classification) were compared by χ² test or Fisher test.

RESULTS

Median survival of pancreas was 66 months, with no significant difference between groups (P > .05). Multivariate analysis showed risk factors to be donor age, cold ischemia time, donor body mass index, receipt body mass index, and receipt panel-reactive antibody.

CONCLUSIONS

In our series, the use of pancreatic grafts from donors with expanded criteria is safe and has increased the pool of grafts. Different variables, both donor and recipient, influence the survival of the pancreatic graft and should be taken into account in organ distribution systems.

Pretransplant interferon-γ secretion by CMV-specific CD8+ T cells informs the risk of CMV replication after transplantation

In this prospective study we analyzed pretransplant interferon-γ secretion by cytomegalovirus (CMV)-specific CD8+ T cells to assess its possible utility in determining the risk of CMV replication after solid organ transplantation. A total of 113 lung and kidney transplant patients were enrolled in the study but only 55 were evaluable. All CMV-seronegative recipients were pretransplant "nonreactive" (IFNγ <0.2 IU/mL) (11/11), whereas 30/44 (68.2%) CMV-seropositive (R+) recipients were "reactive" (IFNγ ≥0.2 IU/mL) and 14/44 (31.8%) were "nonreactive". In the R(+) "nonreactive" group, 7/14 (50%) developed posttransplant CMV replication, whereas the virus replicated only in 4/30 (13.3%) of the R(+) "reactive" patients (p = 0.021). According to the best multivariate model, pretransplant "nonreactive" recipients receiving an organ from a CMV-seropositive donor had a 10-fold increased risk of CMV replication compared to pretransplant "reactive" recipients (adjusted OR 10.49, 95% CI 1.88-58.46). This model displayed good discrimination ability (AUC 0.80) and calibration (Hosmer-Lemeshow test, p = 0.92). Negative and positive predictive values were 83.7% and 75%, respectively. The accuracy of the model was 82%. Therefore, assessment of interferon-γ secretion by cytomegalovirus (CMV)-specific CD8+ T cells prior to transplantation is useful in informing the risk of posttransplant CMV replication in solid organ transplant patients.

Recurrent membranoproliferative glomerulonephritis after second renal graft treated with plasmapheresis and rituximab

We present a case of a 45-year-old man who suffered from idiopatic membranoproliferative glomerulonephritis (MPGN) in the native kidney that relapsed after his first and second renal grafts. The patient was diagnosed in 1990 with lobular MPGN type I, receiving his first renal graft in 1996. In 2001, a biopsy showed recurrence of MPGN type I (rMPGN). He underwent a second renal graft in 2008. In January 2010, he experienced increased proteinuria and creatinine. Upon electron microscopy of a renal graft biopsy we diagnosed a new rMPGN. At the time of the biopsy, complement levels were normal, although C3 and C4 decreased further. We administered 12 plasmapheresis (PP) sessions and four doses of rituximab. Due to persistent renal impairment, we performed a new biopsy 3 months later, showing less severity of the acute lessions. He received a new cycle of treatment (PP+rituximab). One year later, his renal function was stable with a creatinine ranging between 2 and 2.5 mg/dL and a protein/creatinine ratio less than 1 mg/mg. We concluded that the treatment stopped the disease progression.

Impact of recurrent glomerulonephritis on renal graft survival

BACKGROUND

Glomerular disease causes graft loss in the intermediate and long term, especially recurrent primary renal disease, negatively impacting graft survival. Thus, it must be considered a differential diagnosis in the evaluation of chronic graft dysfunction.

METHODS

The objectives of our study were to compare the impacts of primary glomerular disease on graft survival and association with interstitial fibrosis/tubular atrophy (IFTA) or transplant glomerulopathy. We examined the influence of the relapse of glomerulonephritis (GN) on renal graft survival in a retrospective study of 1057 patients undergoing renal transplantations between March 1981 and October 2009. Among this group, 128 patients were diagnosed with pretransplant GN by renal biopsy. We examined graft survival on recurrence compared with IFTA and transplant glomerulopathy using Kaplan-Meier analysis.

RESULTS

We analyzed a cohort of 128 patients who were diagnosed with pretransplant GN by renal biopsy, including 28.9% (37) of whom were males. The mean age was 42.04 ± 13.82 years. The most frequent type was immunoglobulin A GN (IgAGN; 31.3%), followed by membranoproliferative GN (MPGN; 28.9%), rapidly progressive GN (RPGN; 16.4%), focal-segmental GN (FSGN; 13.3%), membranous GN (9.4%), and minimal change GN; (0.8%). Among the 16 cases (12.5%) of GN recurrence; MPGN was associated most frequently (n = 10, 28.9%), followed by FSGN (n = 4, 23.5%), RPGN (n = 1, 4.8%), and IgAGN (n = 1, 2.5%). We noted that 11.8% of subjects to be positive for hepatitis C virus; while 3.9% were hepatitis B virus(HBV)-positive. We observed no differences in hepatic serology between patients who experienced recurrence (HBV 6.3% vs hepatitis C virus [HCV] 18.8%) compared with IFTA (HBV 3.1% vs HCV 9.4%). Fifty-one patients (39.8%) were biopsied after transplantation due to impaired renal function: there were recurrences of GN in 12.5% (n = 16), IFTA in 25% (n = 32), and transplant glomerulopathy in 2.3% (n = 3) cases. The average graft survival in our cohort was 8.36 ± 0.59 years. The median patient survival among those who experienced a recurrence was 8.36 ± 1.79 years; 7.19 ± 1.01 years in IFTA patients; and 3.31 ± 0.91 years in patients with transplant glomerulopathy (log-rank P = .06). Upon multivariate analysis, recurrence of GN was not an independent predictor of renal loss.

CONCLUSIONS

MPGN was the type of GN that recurred most frequently followed by FSGN. No differences in graft survival were noted between long-term recurrence of GN and other causes of chronic graft dysfunction. The recurrence of primary disease did not worsen the renal graft prognosis versus other causes of chronic graft dysfunction.

Results of living kidney donation in Andalusia: 2006-2009

Renal transplantation is the best therapeutic choice in patients with end-stage renal disease (ESRD), with donation from living donors the alternative that offers the best medium- and long-term results. Because of the limited number of cadaver donors and the progressive increase in donor age, transplantation from living donors has become the renal replacement treatment of choice. Several studies have demonstrated that donation does not increase the donor's risk of developing ESRD in the long term. Some studies have asserted that a donor's life expectancy increases as a result of the comprehensive study and screening process they must undergo. The objective of the present study was to evaluate the vital status and onset of chronic renal disease in 101 living kidney donors in Andalusia, Spain, during 2006-2009, based on data obtained from the Sistema de Información de la Coordinación Autonómica de Trasplantes de Andalucía (Regional Transplants Coordination of Andalusia). Donor survival was 99%, and the only death, from lung cancer, was not associated with the surgical procedure. Only 5 transplants failed during this period, and no donors developed ESRD. Neither the probability of survival nor the risk of developing ESRD in donors was influenced by kidney donation.

Blood pressure and body water distribution in chronic renal failure patients

Evidence exists of the important role of sodium balance and extracellular fluid volume in the genesis of hypertension in chronic renal failure (CRF). Several studies have shown that patients with advanced CRF have an increased, interstitial and intravascular, extracellular water volume (ECW). The relationship between the increase in ECW and high blood pressure has also been reported. Using electric bioimpedance, body water distribution was studied in 32 patients from our dialysis unit. Twelve of these patients were hypertensive and 20 had normal blood pressure. Hypertensive patients had a significantly greater total body water volume and ECW than the normotensive patients. Given the importance of ECW in controlling blood pressure, one of the main aims of haemodialysis is a suitable extraction of sodium and water during the treatment. Despite technological advances in dialysis therapy, cardiovascular instability during treatment is still a clinical problem. In recent years, new strategies to control ECW, with good haemodynamic tolerance, have been developed. These strategies include haemofiltration, haemodiafiltration and sodium and ultrafiltration profiles.

Cardiovascular response to hemodialysis: the effects of uremia and dialysate buffer

Cardiovascular instability continues to be one of the primary clinical problems in hemodialysis. Acetate buffer in dialysate is one of the factors that may induce hypotension. Since uremia may have a direct effect on the regulation of the cardiovascular system, the present study was designed to investigate the separate effects of uremia and acetate hemodialysis on blood pressure in anesthesized dogs, as well as the hemodynamic parameters determined by invasive cardiovascular monitoring. Animals were separated into four groups: (1) group I, hemodialysis with acetate in controls; (2) group II, hemodialysis with acetate in uremic dogs; (3) group III, hemodialysis with bicarbonate in controls; and (4) group IV, hemodialysis with bicarbonate in uremic dogs. Acute uremia was induced by bilateral ureteral ligation and a 90-minute hemodialysis (acetate or bicarbonate) procedure was performed 72 hours later. The results obtained in this study show that, compared with dogs with normal renal function, acute uremia resulted in an elevation in mean arterial pressure (MAP; 178 +/- 13 vs. 115 +/- 23 mm Hg, P < 0.01), which was associated with an increase in cardiac index (CI) and left ventricular stroke work index (LVSWI). In these dogs, the pulmonary capillary wedge pressure (PCWP; preload) and the systemic vascular resistance index (SVRI; afterload) were not different than controls. In uremic dogs, hemodialysis with acetate, but not with bicarbonate, decreased the MAP to values similar to controls. The decrease in MAP induced by acetate hemodialysis in uremic dogs was associated with a decrease in SVRI and PCWP. These results suggest that in dogs with acute uremia, acetate hemodialysis (HD) decreases myocardial contractility that was previously increased by a direct effect of uremia. In controls, acetate produced a moderate decrease in MAP that was the result of a mild decrease in CI and SVR. Since PCWP was not significantly decreased after acetate HD, the decrease in CI can be attributed to a mild decrease in myocardial performance. In conclusion, this study in dogs suggests that uremia enhances myocardial contractility directly. Acetate hemodialysis reduces this elevated myocardial contractility to normal values.