Model for end-stage liver disease (MELD) exception for polycystic liver disease
Polycystic liver disease (PLD) is commonly associated with polycystic kidney disease, but is unaccompanied by renal cysts in 10% of cases. Symptomatic PLD is mainly limited to adults and rarely, if ever, presents in childhood. There is currently no effective medical therapy for PLD. Most patients who have PLD require no medical or surgical intervention. Patients with PLD rarely, if ever, experience biochemical hepatic deterioration, and classic symptoms of hepatic failure such as ascites, variceal hemorrhage, or encephalopathy are unusual.1–3 Although there is a typical lowering of the quality of life in these patients, to date, quality of life (although not well studied) has not been associated with decreased survival. Serious, life-threatening complications related to multiple hepatic cysts may occur, including cyst infection, hepatic vein outflow obstruction, portal hypertension, refractory ascites after cyst fenestration, cyst carcinoma, cholangiocarcinoma, and most importantly, pain and/or chronic wasting with malnutrition.2–4
Symptomatic PLD only occurs in patients with massive hepatic cystic disease in which the total cyst:parenchyma ratio is >1.5 Patients with PLD on hemodialysis are at greatest risk of life-threatening complications due to hepatic cysts complicated by infection, hemorrhage, and carcinoma. In one center, 10% of the mortality in patients with PLD on hemodialysis was attributed to these complications. However, this observation has not been confirmed by other centers. Nontransplant interventions that can relieve symptoms of massive hepatic cystic disease include percutaneous cyst puncture and sclerotherapy, laparoscopic cyst decompression, open laparotomy with fenestration, and liver resection.3, 6–10 These interventions can provide temporary or prolonged relief of symptoms but may be associated with significant morbidity and even mortality. Open surgical decompression is associated with a very low mortality rate but is associated with substantial morbidity. Laparoscopic decompression reduces hospital length of stay but is also associated significant morbidity.6 Liver resection is indicated only in highly selected patients and is associated with the potential for frequent morbidity and significant mortality.
Liver transplantation (LT), the ultimate treatment for PLD, eliminates the disease and its complications and provides long-lasting relief of symptoms.11–14 Approximately 40% of those undergoing LT will require simultaneous kidney transplantation. Five-year survival after LT or liver-kidney transplantation is approximately 70 to 75%, and much of the mortality is in the first year. LT with or without kidney transplantation should be avoided in severely malnourished or debilitated patients. Patients with PLD may be candidates for living-donor LT. Patients with PLD generally have preserved liver function and normal Model for End-Stage Liver Disease (MELD) scores if they do not have renal involvement.
CRITERIA FOR LISTING PATIENTS WITH PLD FOR LT
Patients with PLD should meet the following criteria in order to be listed for LT:
Satisfy criteria for massive PLD (total cyst:parenchyma ratio >1) and have a complication of the PLD that is likely to resolve after LT.
Are not candidates for, or have disease that has failed to respond to, nontransplant interventions for relief of symptoms; malnutrition may be considered a primary contraindication to nontransplant surgery.
Have clinically significant manifestations of liver disease that can be attributed to massive PLD, which may include cachexia, ascites, portal hypertension (variceal bleeding), hepatic venous outflow obstruction, biliary obstruction, cholestasis, or recurrent cyst infection.
Have severe malnutrition (assessment made on the basis of hypoalbuminemia or decreased lean body mass).
Have serum albumin <2.2 mg/dL.
Have lean body mass reflected by decreased midarm circumference, measured in the nondominant arm midway between the acromion and the olecranon process: <23.1 cm in female patients and <23.8 cm in male patients.
SYNTHESIS OF AVAILABLE DATA
There are insufficient data to justify automatic priority for patients with PLD.
PROPOSAL FOR STANDARDIZED MELD EXCEPTIONS FOR CANDIDATES WITH PLD
We propose that PLD continue to be addressed by Regional Review Boards by using the following criteria, with data to be prospectively collected by the United Network for Organ Sharing and additional MELD priority assigned on a case-by-case basis; additional MELD priority should not be automatically granted at this time. Cyst carcinoma should not be used as an indication for standardized MELD exception because this disease is associated with poor survival or the prognosis is unknown, and LT for quality of life should not be a consideration to support upgrading patients to a higher MELD score. Patients who meet the criteria below should be granted a MELD score exception:
Patients without renal insufficiency may receive a MELD score of 15. The score may be increased by an additional 3 points every 3 months upon reapplication with submission of current clinical data.
Patients with renal insufficiency (defined as glomerular filtration rate or creatinine clearance < 30 mL/min) may receive a MELD score of 20. The score may be increased by an additional 3 points every 3 months upon reapplication.
Clinical data that need to prospectively collected and be submitted to the Regional Review Boards include documentation of recurrent cyst infection by culture reports, and weight of the explant liver and the ratio of the liver weight to patient height to determine whether these parameters correlate with patient outcome. In addition, the Regional Review Boards may require vascular studies (full reports with computed tomographic scans, magnetic resonance imaging, or angiography) to document cases of vascular occlusion.