The introduction of MELD (model for end-stage liver disease) prioritization for liver transplant, which is greatly influenced by renal dysfunction, has coincided with an increase in simultaneous liver–kidney transplantation (SLK). SLK has increased from an average of 110 per year pre-MELD up to 368 in 2006 post-MELD (1). A prime motivation to perform SLK in end-stage liver disease (ESLD) candidates is the potent negative impact of renal insufficiency (acute or chronic) on liver transplant outcomes (2,3). Several large studies over the last 11 years have shown that pre-transplant renal failure is associated with increased post-transplant end-stage renal disease (ESRD), higher mortality and diminished quality of life (2–5). Controversy surrounding SLK centers on the questions of how to determine recovery of acute kidney injury (AKI) in the setting of ESLD and the ‘net benefit’ of kidney transplant in liver candidates with kidney failure. Furthermore, the higher MELD scores in transplant candidates receiving liver transplant alone (LTA) compared to SLK also suggest some SLK (with ESRD) have less severe liver disease than LTA and may be receiving a liver transplant prematurely.
Disparity in the recovery of AKI in waitlisted candidates and the level of kidney dysfunction at transplant for SLK compared to kidney transplant alone (KTA) recipients is demonstrated by the following data. In 2005, 59.0% of those receiving deceased donor SLK were on dialysis at transplant compared to 85.6% of those receiving a KTA. The average pre- and post-MELD era MDRD (modification of diet in renal disease) calculated glomerular filtration rate (eGFR) of recipients not on dialysis at kidney transplantation has been consistently higher for SLK compared to KTA recipients (Tables 1 and 2). Since MELD allocation began, 15% (40/265) of those on dialysis at listing for LTA have discontinued dialysis by the time of transplant where as 6.5% (n = 24/371) of those listed for SLK and 4.3% (771/17 862) of those listed for KTA have discontinued dialysis prior to transplant (Table 3).
|Type of listing||LTA no dialysis||SLK no dialysis||KTA no dialysis|
|Type of TX||LTA no dialysis||SLK no dialysis||KTA no dialysis|
|No dialysis at transplant||Dialysis at transplant|
|No dialysis at listing||10 972||301|
|Dialysis at listing||40||225|
|No dialysis at listing||296||89|
|Dialysis at listing||24||347|
To review the impact of renal disease on liver transplant outcome, the benefit of SLK and to better standardize the evaluation and selection of SLK candidates, a consensus conference of hepatologists, transplant surgeons, nephrologists and coordinators convened in March 2006. The agenda included a review of the Scientific Registry of Transplant Recipients (SRTR) liver transplant data (with a focus on the post-MELD data) and individual center reports on factors predicting post-transplant renal failure such as the pre-transplant duration of dialysis and renal histology. After the data presentation, participants met in work groups to discuss the following topics: the evaluation of kidney disease in ESLD, selection criteria for SLK, impact of hepatorenal syndrome (HRS) treatment on kidney function, treatment of acute renal failure in liver failure and new data needed to better identify risk factors for post-transplant renal failure. Each group developed a consensus approach that was presented to all conferees for discussion. This report is the summary of consensus agreements reached during these discussions. The writing of this consensus statement was the responsibility of the work group leaders and presenters of the individual center data.