Successful living donor liver transplantation for polycystic liver in a patient with autosomal-dominant polycystic kidney disease

PRKX, a Novel cAMP-Dependent Protein Kinase Member, Plays an Important Role in Development

The human protein kinase X gene (PRKX) and cAMP-dependent protein kinase (PKA) are both c-AMP-dependent serine/threonine protein kinases within the protein kinase AGC subgroup. Of all the protein kinases in this group, PRKX is the least studied. PRKX has been isolated from patients with chondrodysplasia punctate and is involved in numerous processes, including sexual differentiation and fertilization, normal kidney development and autosomal dominant polycystic kidney disease (ADPKD), blood maturation, neural development, and angiogenesis in vitro. Although the role of PRKX in development and disease has been reported recently, the underlying mechanism of PRKX activity is largely unknown. In addition, based on the expression pattern of PRKX and the extensive role of PKA in disease and development, PRKX might have additional crucial functions that have not been addressed in the literature. In this review, we summarize the characteristics and developmental functions of PRKX that have been reported by recent studies. In particular, we elucidate the structural and functional differences between PRKX and PKA, as well as the possible roles of PRKX in development and related diseases. Finally, we propose future studies that could lead to important discoveries of more PRKX functions and the underlying mechanisms involved.

Excellent survival after liver transplantation for isolated polycystic liver disease: an European Liver Transplant Registry study

Patients with end-stage isolated polycystic liver disease (PCLD) suffer from incapacitating symptoms because of very large liver volumes. Liver transplantation (LT) is the only curative option. This study assesses the feasibility of LT in PCLD. We used the European Liver Transplant Registry (ELTR) database to extract demographics and outcomes of 58 PCLD patients. We used Kaplan-Meier survival analysis for survival rates. Severe abdominal pain (75%) was the most prominent symptom, while portal hypertension (35%) was the most common complication in PCLD. The explantation of the polycystic liver was extremely difficult in 38% of patients, because of presence of adhesions from prior therapy (17%). Karnofsky score following LT was 90%. The 1- and 5-year graft survival rate was 94.3% and 87.5%, while patient survival rate was 94.8% and 92.3%, respectively. Survival rates after LT for PCLD are good.

Living donor liver transplantation in polycystic liver disease

In the current Model for End-Stage Liver Disease system, patients with polycystic liver disease (PCLD) who have a poor quality of life secondary to their massive hepatomegaly are no longer competitive for a deceased donor liver transplant if their liver function is well preserved. Traditionally, a caval resection has been advocated in these patients because of the difficulty of the hepatectomy with hepatomegaly, which makes living donation impossible. This series looks at 3 patients who underwent a caval sparing hepatectomy and subsequent living donor liver transplantation (LDLT) for PCLD. Graft and patient survival was 100%, and there were few complications in either donors or recipients. LDLT is an ideal option for patients with PCLD and preserved liver function but poor quality of life.

Surgical management of polycystic liver disease

Adult polycystic liver disease (PCLD) is an autosomal dominant condition commonly associated with autosomal dominant polycystic kidney disease (ADPKD). However in the last decade, it has been recognized that there is a distinct form of autosomal dominant PCLD that arises without concomitant ADPKD. Early knowledge of the pathogenesis was gained from the study of hepatic cysts in patients with ADPKD. Bile duct overgrowth after embryogenesis results in cystic hepatic dilatations that are known as biliary microhamartomas or von Meyenburg complexes. Further dilatation arises from cellular proliferation and fluid secretion into these cysts. There is a variable, broad spectrum of manifestations of PCLD. Although PCLD is most often asymptomatic, massive hepatomegaly can lead to disabling symptoms of abdominal pain, early satiety, persistent nausea, dyspnea, ascites, biliary obstruction, and lower body edema. Complications of PCLD include cyst rupture and cyst infection. Also, there are associated medical problems, especially intracranial aneurysms and valvular heart disease, which clinicians need to be aware of and evaluate in patients with PCLD. In asymptomatic patients, no treatment is indicated for PCLD. In the symptomatic patient, surgical therapy is the mainstay of treatment tailored to the extent of disease for each patient. Management options include cyst aspiration and sclerosis, open or laparoscopic fenestration, liver resection with fenestration, and liver transplantation. The surgical literature discussing treatment of PCLD, including techniques, outcomes, and complication rates, are summarized in this review.

Outcome and quality of life in patients with polycystic liver disease after liver or combined liver-kidney transplantation

In advanced stages of polycystic liver disease, often associated with polycystic kidney disease, a curative therapy is liver or combined liver-kidney transplantation. However, little is known about long-term outcome and quality of life. Between 1990 and 2003, 36 patients (32 female, 4 male) with polycystic liver or combined liver-kidney disease underwent liver (n = 21) or liver-kidney (n = 15) transplantation at our center. Main indications for liver transplantation were cachexia, muscle atrophy, loss of weight, recurrent cyst infections, portal hypertension, and ascites. Apart from clinical parameters, 2 anonymous questionnaires (standard short form 36 and self-designed) addressing quality of life and social status were evaluated. Five patients (14 %) died due to sepsis or myocardial infarction with pneumonia, all within 61 days after transplantation. The follow-up time of the remaining 31 patients ranged from 5 to 156 months, with a mean of 62 months. Of the 23 (74%) answered the questionnaires, 91% of patients felt "much better" or "better," only 9% felt "worse" than before, and 52% of patients participated in sports regularly. Fatigue, physical fitness, loss of appetite, and vomiting improved significantly after transplantation. Physical attractiveness and interest in sex increased as well. Professional occupation did not change for 71% of patients. Family situation before and after transplantation changed in 1 case only. Finally, 78% of patients said they would opt for transplantation again, while 17% were undecided; 1 patient would not repeat transplantation. In conclusion, patients with advanced polycystic liver or polycystic liver-kidney disease have an excellent survival rate and an improved quality of life after liver or combined liver-kidney transplantation.

New advances in evaluation and management of patients with polycystic liver disease

Adult polycystic liver disease (APLD) is an autosomal dominant condition most commonly associated with polycystic kidney disease. However, over the last decade it has come to be recognized that APLD is a genetically heterogeneous disorder involving derangements on at least three different chromosomes. Mutations involving chromosomes 16 and 4 accounting for autosomal dominant polycystic kidney disease (ADPKD) type 1 and type 2 have been well described as have their gene products, polycystin-1 and polycystin-2. These have since been joined by a more recently recognized mutation in the short arm of chromosome 19 thought to be responsible for a much rarer form of autosomal dominant polycystic liver disease without any associated renal involvement. Despite the sometimes impressive physical and radiologic findings, only a minority of patients will progress to advanced liver disease or develop complications as a result of massive hepatomegaly. In these patients, medical management alone has proved ineffectual. Therefore, in the symptomatic APLD patient, surgical therapy remains the mainstay of therapy and includes cyst aspiration and sclerosis, fenestration with and without hepatic resection and orthotopic liver transplantation. The surgical literature on treatment of APLD, to include outcome measurements and complication rates are summarized. Additionally, we review other potential organ involvement and resultant complications.

Establishment of Highly Differentiated Immortalized Human Hepatocyte Line With Simian Virus 40 Large Tumor Antigen for Liver Based Cell Therapy

Acute liver failure and metabolic liver disorder animal models have demonstrated that hepatocytes transplanted into the liver or spleen survive and participate in the liver repopulation process, and recent studies have documented the usefulness of hepatocyte transplantation in humans. However, despite the promising cell therapy, there are still many restrictions, such as the shortage of donor human livers and the limited lifespan and the functional insufficiency of primary cultured hepatocytes. The immortalized and highly differentiated human hepatocyte could provide an unlimited supply of transplantable cells. In this study, we established an efficient and highly differentiated immortalized human hepatocyte line for bioartificial liver and hepatocyte transplantation research. Hepatocytes isolated from the liver of a 25 year old, brain dead male were transfected with pcDNA3.1 (-) recombinant plasmid containing the genes encoding simian virus 40 (SV40) large tumor antigen. One of the hepatocyte clones, HepLL, displayed highly differentiated liver functions with immortalized characteristics and was selected with a 700-300 microg/ml of G418 technique in 42 days. To characterize this immortalized cell line for cell therapy in the near future, HepLL cells were studied with immunohistochemistry, reverse transcription-polymerase chain reactions, immunoblotting, and tumorigenicity tests. The results revealed that HepLL cells displayed morphologic characteristics of liver parenchymal cells, secreted albumin, synthesized urea and glycogen, and expressed liver enriched functional markers, but there were no tumorigenic qualities after transplantation into severe combined immunodeficiency mice. Thus this immortalized human hepatocyte line is expected to be a useful tool for studying the functions of differentiated human hepatocyte and a promising strategy to resolve the shortages of donor organs and the limits of primary human hepatocyte for transplantation and bioartificial liver support systems.