Outcomes and native renal recovery following simultaneous liver-kidney transplantation.

With the increase in patients having impaired renal function at liver transplant due to MELD, accurate predictors of posttransplant native renal recovery are needed to select candidates for simultaneous liver-kidney transplantation (SLK). Current UNOS guidelines rely on specific clinical criteria for SLK allocation. To examine these guidelines and other variables predicting nonrecovery, we analyzed 155 SLK recipients, focusing on a subset (n = 78) that had post-SLK native GFR (nGFR) determined by radionuclide renal scans. The 77 patients not having renal scans received a higher number of extended criteria donor organs and had worse posttransplant survival. Of the 78 renal scan patients, 31 met and 47 did not meet pre-SLK UNOS criteria. The UNOS criteria were more predictive than our institutional criteria for all nGFR recovery thresholds (20-40 mL/min), although at the most conservative cut-off (nGFR ≤ 20) it had low sensitivity (55.3%), specificity (75%), PPV (67.6%) and NPV (63.8%) for predicting post-SLK nonrecovery. On multivariate analysis, the only predictor of native renal nonrecovery (nGFR ≤ 20) was abnormal pre-SLK renal imaging (OR 3.85, CI 1.22-12.5). Our data support the need to refine SLK selection utilizing more definitive biomarkers and predictors of native renal recovery than current clinical criteria.

Differential effects of very high doses of doxercalciferol and paricalcitol on serum phosphorus in hemodialysis patients.

BACKGROUND: Treatment of secondary hyperparathyroidism (SHPT) includes use of calcitriol (1,25D(3)) to suppress parathyroid hormone (PTH), but dosing of 1,25D(3) is limited by the development of hypercalcemia and a high calcium x phosphorus (Ca x P) product due to gut absorption of calcium and phosphorus as well as enhanced bone resorption. The vitamin D analog 19-Nor-1,25(OH)2-vitamin D2 (paricalcitol) and the prohormone 1alpha-OH-vitamin D2 (doxercalciferol) have been proposed as alternatives which may cause less hypercalcemia and elevated Ca x P, while still suppressing PTH. METHODS: We performed a prospective study to assess the acute bone mobilization effects of very high doses of paricalcitol and doxercalciferol. 13 hemodialysis patients received 160 mcg of paricalcitol and 120 mcg of doxercalciferol on 2 separate occasions in a research center while on a low calcium, low phosphorus diet, and sevelamer alone as a phosphorus binder. Changes in Ca, PO4, and PTH were measured over 36 h. RESULTS: Serum phosphorus rose faster, and peaked significantly higher at 36 h following doxercalciferol (2.12 +/- 0.11 mmol/l) than paricalcitol (1.85 +/- 0.07 mmol/l; p = 0.025). Ca x P product also rose more following doxercalciferol than paricalcitol, and peaked higher at 36 h (5.02 +/- 0.26 vs. 4.54 +/- 0.21 mmol/l; p = 0.061). In contrast, suppression of PTH at 36 h was comparable (63% after paricalcitol and 65% with doxercalciferol). CONCLUSION: Consistent with animal studies, paricalcitol provides profound PTH suppression, while stimulating bone resorption and/or intestinal absorption less than doxercalciferol, resulting in less elevation of serum phosphorus and Ca x P.

Flow in hemodialysis grafts after angioplasty: Do radiologic criteria predict success?

BACKGROUND: The anatomic success of percutaneous angioplasty of venous stenosis is determined by the improvement in cross-sectional diameter of the vessel. A successful outcome is defined as a residual stenosis of <30%. The purpose of this study was to determine whether the angiographic assessment of a venous stenosis correlates with the change in graft blood flow following angioplasty. METHODS: Twenty-two hemodialysis patients with decreased intragraft blood flow (<700 mL/min) underwent diagnostic fistulography and angioplasty. All grafts were patent at the time of the procedure. Intragraft blood flow was measured before and after angioplasty using the ultrasonic dilution technique. Change in graft blood flow after angioplasty was correlated to the morphologic changes of the treated stenosis. RESULTS: The mean preangioplasty and postangioplasty graft blood flows were 457 +/- 136 and 818 +/- 202 mL/min, respectively. The mean degree of stenosis before angioplasty was 74 +/- 15% and 18 +/- 14% after dilation (P < 0.001). The only variable that significantly correlated with postangioplasty blood flow was preangioplasty flow (r2 = 0.22, P < 0.001). The postangioplasty blood flow was not significantly different than the highest recorded blood flow measured in that graft (798 +/- 213 mL/min, P = NS). There was no significant correlation between the change in blood flow and the change in percentage of stenosis. CONCLUSION: Following angioplasty of a venous stenosis, the graft blood flow is most closely predicted by the preprocedural blood flow and is similar to the highest recorded blood flow ever measured in that graft. Angiographic criteria to assess the success of angioplasty are not predictive of changes in blood flow.