Isolated polycystic liver disease

Genetic Analysis of Severe Polycystic Liver Disease in Japan

Key Points

Among patients with severe polycystic liver disease (PLD) (height-adjusted total liver volume of <1800 ml/m), PKD2 variants were found in 34%. Three patients with PKD1 or PKD2 variants are reported with severe PLD but normal-sized kidneys (hTKV of < 250 ml/m).

Background

Polycystic liver disease (PLD) is present in most patients with autosomal dominant polycystic kidney disease (ADPKD). PLD can alternatively be found with few, if any, kidney cysts as a diagnosis of isolated PLD (autosomal dominant PLD [ADPLD]). Several genes are identified as causative for this spectrum of phenotypes; however, the relative incidence of genetic etiologies among patients with severe PLD is unknown.

Methods

Patients with ADPKD or ADPLD having severe PLD defined as height-adjusted total liver volume (hTLV) >1800 ml/m were recruited. Subsequent clinical care was followed. Genetic analysis was performed using whole exome sequencing.

Results

We enrolled and sequenced 49 patients (38 women, 11 men). Pathogenic or suspected pathogenic variants in polycystic disease genes were found in 44 of 49 patients (90%). The disease gene was PKD1 in 20 of 44 patients (45%), PKD2 in 15 of 44 patients (34%), PRKCSH in 5 of 44 patients (11%), GANAB in 2 of 44 patients (5%), SEC63 in 1 of 44 patients (2%), and ALG8 in 1 of 44 patients (2%). The median hTLV was no different between genetically defined ADPKD and ADPLD groups (4431 [range, 1817–9148] versus 3437 [range, 1860–8211]) ml, P = 0.77), whereas height-adjusted kidney volume was larger as expected in ADPKD than in ADPLD (607 [range, 190–2842] versus 179 [range, 138–234] ml/m, P < 0.01). Of the clinically defined ADPKD patients, 20 of 38 patients (53%) were PKD1 , 15 of 38 (39%) were PKD2 , and 3 (8%) remained genetically unsolved. Among patients with a pathogenic PKD1 or PKD2 variant, we found three patients with a liver-dominant ADPKD (severe PLD with height-adjusted total kidney volume <250 ml/m).

Conclusions

ADPLD-related genes represent 20% of patients with severe PLD in our cohort. Of those enrolled with ADPKD, we observed a higher frequency of PKD2 carriers than in any previously reported ADPKD cohorts. Although there was no significant difference in the hTLV between patients with PKD1 and PKD2 in this cohort, our data suggest that enrollment on the basis of severe PLD may enrich for patients with PKD2 .

Imaging features and management of focal liver lesions

Notably, the number of incidentally detected focal liver lesions (FLLs) has increased dramatically in recent years due to the increased use of radiological imaging. The diagnosis of FLLs can be made through a well-documented medical history, physical examination, laboratory tests, and appropriate imaging methods. Although benign FLLs are more common than malignant ones in adults, even in patients with primary malignancy, accurate diagnosis of incidental FLLs is of utmost clinical significance. In clinical practice, FLLs are frequently evaluated non-invasively using ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI). Although US is a cost-effective and widely used imaging method, its diagnostic specificity and sensitivity for FLL characterization are limited. FLLs are primarily characterized by obtaining enhancement patterns through dynamic contrast-enhanced CT and MRI. MRI is a problem-solving method with high specificity and sensitivity, commonly used for the evaluation of FLLs that cannot be characterized by US or CT. Recent technical advancements in MRI, along with the use of hepatobiliary-specific MRI contrast agents, have significantly improved the success of FLL characterization and reduced unnecessary biopsies. The American College of Radiology (ACR) appropriateness criteria are evidence-based recommendations intended to assist clinicians in selecting the optimal imaging or treatment option for their patients. ACR Appropriateness Criteria Liver Lesion-Initial Characterization guideline provides recommendations for the imaging methods that should be used for the characterization of incidentally detected FLLs in various clinical scenarios. The American College of Gastroenterology (ACG) Clinical Guideline offers evidence-based recommendations for both the diagnosis and management of FLL. American Association for the Study of Liver Diseases (AASLD) Practice Guidance provides an approach to the diagnosis and management of patients with hepatocellular carcinoma. In this article, FLLs are reviewed with a comprehensive analysis of ACR Appropriateness Criteria, ACG Clinical Guideline, AASLD Practice Guidance, and current medical literature from peer-reviewed journals. The article includes a discussion of imaging methods used for the assessment of FLL, current recommended imaging techniques, innovations in liver imaging, contrast agents, imaging features of common nonmetastatic benign and malignant FLL, as well as current management recommendations.

Isolated polycystic liver disease in a child

INTRODUCTION

Polycystic liver disease (PCLD) is a genetic disorder characterized by the growth of >10 cysts in the liver. PCLD is associated with polycystic kidney disease (PKD) in 80-90%of cases (Kothadia et al., 2023 [1]). PCLD can occur in isolation though rarely in children. We present a case report of a child with symptomatic isolated PCLD.

CASE PRESENTATION

A 23-month old female child presented with a 17-month history of gradual increase in abdominal mass. She had acute onset of postprandial vomiting and shortness of breath while lying flat. On examination, she was irritable with massive abdominal distension. Liver function test done showed markedly elevated liver enzymes with preservation of liver synthesis function. Computed tomography (CT) scan showed a large intra-abdominal cyst and normal kidneys bilaterally. During laparotomy, we found multiple exophytic cysts arising from segment IVa of the liver. Hepatic resection was done successfully and patient recovered uneventfully. Histology showed Von Meyenburg complexes characteristic of PCLD.

CLINICAL DISCUSSION

The goal of management should be to counter symptomatology by intervening on developed cysts. The therapeutic options are individualized to address the symptoms and improve the patients' quality of life. Follow up of the patients is based on the presentation and intervention performed, during which period recurrence of cysts is assessed. Complete resection of the liver cysts is recommended to avoid the risk of cholangiocarcinoma.

CONCLUSION

Close follow up by physical examination, laboratory tests and imaging modalities is necessary to detect any recurring masses and malignancy transformation of the cysts to enable timely intervention.

Operative Outcomes for Polycystic Liver Disease: Results of a Large Contemporary Series

INTRODUCTION

Persistent symptoms of pain, early satiety, dyspnea, and gastrointestinal reflux due to significant liver enlargement are indications for surgical debulking in patients with polycystic liver disease (PCLD) due to the lack of effective medical therapies; however, few data exist on outcomes of surgical intervention for PCLD.

METHODS

We conducted a retrospective analysis of consecutive patients who underwent operative intervention due to persistent symptoms secondary to PCLD. Preoperative patient characteristics, 30-day postoperative outcomes, and long-term postoperative outcomes, including complications and symptom resolution, were analyzed.

RESULTS

We identified 50 patients who underwent hepatic resection for symptomatic PCLD. Nine patients (19%) had concomitant polycystic kidney disease, and 14 (28%) had previously undergone interventions for PCLD management. The overall complication rate was 30%, with 8 patients (16%) experiencing Clavien-Dindo Grade III-V complications and no mortalities. The median relative reduction in liver volume was 41%. At a median follow-up of 2 years, 94% has sustained symptom resolution.

CONCLUSIONS

This is among the largest case series exploring PCLD operative outcomes, revealing that surgical intervention for debulking for advanced PCLD is safe and effective for symptom management. Furthermore, patients with PCLD undergoing hepatectomy tolerate significant liver volume loss without evidence of impaired hepatic function.

The Safety and Efficacy of Hepatic Transarterial Embolization Using Microspheres and Microcoils in Patients with Symptomatic Polycystic Liver Disease

Purpose: We investigated the long-term safety and efficacy of hepatic transarterial embolization (TAE) in patients with symptomatic polycystic liver disease (PLD). Materials and Methods: A total of 26 patients were included, mean age of 52.3 years (range: 33−78 years), undergoing 32 TAE procedures between January 2012 and December 2019 were included in this retrospective study. Distal embolization of the segmental hepatic artery was performed with 300−500 µm embolic microspheres associated with proximal embolization using microcoils. The primary endpoint was clinical efficacy, defined by an improvement in health-related quality of life using a modified Short Form-36 Health Survey and improvement in symptoms (digestive or respiratory symptoms and chronic abdominal pain), without invasive therapy during the follow-up period. Secondary endpoints were a decrease in total liver volume and treated liver volume and complications. Results: Hepatic embolization was performed successfully in 30 of 32 procedures with no major adverse events. Clinical efficacy was 73% (19/26). The mean reduction in hepatic volume was −12.6% at 3 months and −27.8% at the last follow-up 51 ± 15.2 months after TAE (range: 30−81 months; both ps < 0.01). The mean visual analog scale pain score was 5.4 ± 2.8 before TAE and decreased to 2.7 ± 1.9 after treatment. Three patients had minor adverse events, and one patient had an adverse event of moderate severity. Conclusion: Hepatic embolization using microspheres and microcoils is a safe and effective treatment for PLD that improves symptoms and reduces the volume of hepatic cysts.

Molecular Mechanisms of Isolated Polycystic Liver Diseases

Polycystic liver disease (PLD) is a rare autosomal dominant disorder including two genetically and clinically distinct forms: autosomal dominant polycystic kidney disease (ADPKD) and isolated polycystic liver disease (PCLD). The main manifestation of ADPKD is kidney cysts, while PCLD has predominantly liver presentations with mild or absent kidney cysts. Over the past decade, PRKCSH, SEC63, ALG8, and LRP5 have been candidate genes of PCLD. Recently, more candidate genes such as GANAB, SEC61B, and ALR9 were also reported in PCLD patients. This review focused on all candidate genes of PCLD, including the newly established novel candidate genes. In addition, we also discussed some other genes which might also contribute to the disease.

Polycystic Kidney/Liver Disease

Autosomal dominant polycystic kidney disease (ADPKD) is a genetic disorder that leads to chronic kidney disease and end-stage kidney disease (ESKD). Polycystic liver disease (PCLD) is the most common extrarenal manifestation of ADPKD. Though isolated PCLD and PCLD due to ADPKD are genetically distinct, they follow a similar clinical course of hepatomegaly from multiple cysts with preserved liver function. Tolvaptan use in ADPKD can slow down the deterioration of renal function and growth of cysts. Somatostatin analogs can slow the growth of polycystic livers but the effect is short-lived. The only curative therapy for PCLD is liver transplantation. Renal transplantation can significantly improve survival in patients with ESKD due to ADPKD.

Polycystic Liver Disease: Advances in Understanding and Treatment

Polycystic liver disease (PLD) is a group of genetic disorders characterized by progressive development of cholangiocyte-derived fluid-filled hepatic cysts. PLD is the most common manifestation of autosomal dominant and autosomal recessive polycystic kidney diseases and rarely occurs as autosomal dominant PLD. The mechanisms of PLD are a sequence of the primary (mutations in PLD-causative genes), secondary (initiation of cyst formation), and tertiary (progression of hepatic cystogenesis) interconnected molecular and cellular events in cholangiocytes. Nonsurgical, surgical, and limited pharmacological treatment options are currently available for clinical management of PLD. Substantial evidence suggests that pharmacological targeting of the signaling pathways and intracellular processes involved in the progression of hepatic cystogenesis is beneficial for PLD. Many of these targets have been evaluated in preclinical and clinical trials. In this review, we discuss the genetic, molecular, and cellular mechanisms of PLD and clinical and preclinical treatment strategies. Expected final online publication date for the Annual Review of Pathology: Mechanisms of Disease, Volume 17 is January 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Imaging in ductal plate malformations

Ductal plate malformations are a heterogenous group of congenital fibrocystic liver diseases resulting from insult to the ductal plate at various stages of embryogenesis. As a result various biliary malformations, cysts, hamartomas and congenital hepatic fibrosis may be seen. We present a radiological pictorial of ductal plate malformations, accurate diagnosis of which is important for clinical management.

Position paper on liver and kidney diseases from the Italian Association for the Study of Liver (AISF), in collaboration with the Italian Society of Nephrology (SIN)

Liver and kidney are strictly connected in a reciprocal manner, in both the physiological and pathological condition. The Italian Association for the Study of Liver, in collaboration with the Italian Society of Nephrology, with this position paper aims to provide an up-to-date overview on the principal relationships between these two important organs. A panel of well-recognized international expert hepatologists and nephrologists identified five relevant topics: 1) The diagnosis of kidney damage in patients with chronic liver disease; 2) Acute kidney injury in liver cirrhosis; 3) Association between chronic liver disease and chronic kidney disease; 4) Kidney damage according to different etiology of liver disease; 5) Polycystic kidney and liver disease. The discussion process started with a review of the literature relating to each of the five major topics and clinical questions and related statements were subsequently formulated. The quality of evidence and strength of recommendations were graded according to the GRADE system. The statements presented here highlight the importance of strong collaboration between hepatologists and nephrologists for the management of critically ill patients, such as those with combined liver and kidney impairment.

Liver transplantation in adult polycystic liver disease: the Ontario experience

BACKGROUND

Liver transplantation (LT) remains the curative treatment for symptomatic Polycystic Liver Disease (PCLD) patients and is associated with excellent survival rates. The aim of the study is to review the Ontario experience in LT for PCLD.

METHODS

A retrospective study was performed from pre-existing LT databases from the LT Units at Toronto General Hospital and London Health Sciences Center, which are the two LT programs in Ontario, Canada. This database contains demographic, clinical parameters and follow-up of all patients transplanted for PCLD. Data was extracted for patients who underwent LT between January 2000-April 2017 and included follow up until December 31st, 2018.

RESULTS

A total of 3560 patients underwent LT, of whom 51 (1.4%) had PCLD and met inclusion criteria. 43 (84%) of these patients were female. The median physiologic Model for End Stage Liver Disease (MELD-Na) score at time of referral was 13 (IQR = 7-22), however all patients required MELD-Na exception points to receive LT. The median age of transplant was 62 years (IQR = 59-64) for male vs. 52 (IQR = 45-56) for female patients. 33 (65%) of our cohort had PCLD while 9 (17.5%) had ADPKD and 9 (17.5%) had both diseases. 39 (76%) had LT due to symptoms of mass effect, while 8 (16%) had portal hypertensive complications. After a median follow-up of 6.3 (IQR = 2.9-12.5) years, the probability of survival was 96% (95% CI: 90%, 100%). Log-rank test, comparing survival analysis between males and females did not show a statistically significant difference (p = 0.26).

CONCLUSION

Most patients underwent LT for PCLD due to symptoms of mass effect with women being more likely than men to undergo LT. LT for PCLD had excellent long-term survival.

Congenital and hereditary cystic diseases of the abdomen

Congenital and hereditary cystic lesions of the abdomen are relatively rare. Correct diagnosis is critical as they may simulate several other benign and malignant acquired diseases of the abdomen. With the correct and appropriate use of imaging, diagnosis may be relatively straightforward and clinical management may be implemented appropriately. The purpose of this article is to describe imaging findings of common and uncommon congenital and hereditary cystic disease of the abdominal organs.

Liver findings in patients with Carney complex, germline PRKAR1A pathogenic variants, and link to cardiac myxomas

This study aimed to evaluate liver involvement in patients with Carney complex (CNC) based on a large cohort and to analyze any germline PRKAR1A genotype-phenotype association of liver disease. The study included 83 patients with CNC, followed between 1995 and 2018 at a tertiary research center. We reviewed liver images, recorded types and number of lesions and analyzed per genotype: all patients were sequenced for the PRKAR1A gene. A total of 29/83 patients (24.0%) had liver radiological findings. Patients with liver lesion had a significantly higher rate of pathogenic variants detected in the PRKAR1A gene (72.4 vs 38.9%, P = 0.005, respectively). Patients with a pathogenic variant detected on germline PRKAR1A analysis had a higher risk for having a liver lesion compared with patients with wild-type (WT) PRKAR1A alleles (21/42 (50.0%) vs 8/41 (19.5%), respectively, P = 0.004). Among patients with liver lesions, those with a nonsense PRKAR1A pathogenic-variant had more liver lesions (7/7) than among those with other pathogenic-variant types (8/22, P = 0.001). In multivariable analysis, detection of liver lesion(s) was associated with an odds ratio of 5.2 for cardiac myxomas (95% CI 1.55-17.49, P = 0.008). In conclusion, patients with CNC, particularly with a PRKAR1A pathogenic variant, have a higher rate of liver lesions. Additionally, liver lesions are associated with a high risk for cardiac myxomas in this population.

Polycystic liver disease: Classification, diagnosis, treatment process, and clinical management

Polycystic liver disease (PLD) is a rare hereditary disease that independently exists in isolated PLD, or as an accompanying symptom of autosomal dominant polycystic kidney disease and autosomal recessive polycystic kidney disease with complicated mechanisms. PLD currently lacks a unified diagnostic standard. The diagnosis of PLD is usually made when the number of hepatic cysts is more than 20. Gigot classification and Schnelldorfer classification are now commonly used to define severity in PLD. Most PLD patients have no clinical symptoms, and minority with severe complications need treatments. Somatostatin analogues, mammalian target of rapamycin inhibitor, ursodeoxycholic acid and vasopressin-2 receptor antagonist are the potentially effective medical therapies, while cyst aspiration and sclerosis, transcatheter arterial embolization, fenestration, hepatic resection and liver transplantation are the options of invasion therapies. However, the effectiveness of these therapies except liver transplantation are still uncertain. Furthermore, there is no unified strategy to treat PLD between medical centers at present. In order to better understand recent study progresses on PLD for clinical practice and obtain potential directions for future researches, this review mainly focuses on the recent progress in PLD classification, clinical manifestation, diagnosis and treatment. For information, we also provided medical treatment processes of PLD in our medical center.

Intracystic Hemorrhage Complicating Polycystic Liver Disease in a 90-Year-Old Woman

Nonparasitic hepatic cysts are common benign tumors that are often asymptomatic and incidentally discovered on imaging. Intracystic hemorrhage is a rare complication of hepatic cysts. We review the literature and discuss a case of intracystic hemorrhage in a 90-year-old woman with polycystic liver disease. The patient underwent cyst aspiration and percutaneous drain placement with subsequent resolution of symptoms. To our knowledge, we report the oldest patient to present with hemorrhage into a hepatic cyst. This case presents unique challenges in management, both because of the patient's age and because of her polycystic liver disease.

Long-term results of liver transplantation for polycystic liver disease: Single-center experience in China

The aim of the present study was to explore the indications for and safety of orthotopic liver transplantation for polycystic liver disease (PLD). Orthotopic liver transplantation in 11 patients with PLD between May 2004 and September 2013 was retrospectively analyzed. Patient epidemiological, clinical and follow-up data were collected. The survival rate was calculated using the Kaplan-Meier method. Over the 10-year period, 11 patients received orthotopic liver transplantation (n=9) and combined liver-kidney transplantation (n=2) for PLD. The recipients' median age was 56 years [(interquartile range (IQR), 52-57 years], and 7 of the patients (63.6%) were classified as having Gigot type II PLD and 4 (36.4%) as having Gigot type III. A total of 8 (72.7%) patients had a severely decreased quality of life (Eastern Cooperative Oncology Group performance status score, ≥3). Only 3 cases (27.3%) were of Class C stage. The mean hospitalization duration was 45.4±15.3 days and the mean length of stay at the intensive care unit was 4.1±1.9 days. The peri-operative mortality was 18.2% and the morbidity was 54.5%. The median follow-up period was 111 months (IQR, 33-132 months). A total of 2 patients died of severe complications after combined liver-kidney transplantation. Furthermore, 1 patient died of ischemia cholangitis during the follow-up period. The actuarial 1-, 5- and 10-year survival rate during the follow-up period was 81.8, 81.8 and 65.5%, respectively. The mean physical component summary score was 87.1±6.9 and the mean mental component summary score was 81.5±6.4. In conclusion, liver transplantation is the only curative procedure for PLD, and the present study indicated that it is relatively and safe and leads to good long-term prognosis and high quality of life. Based on our experience and results, liver transplantation is a primary option for cases of PLD with progressive or advanced symptomatic disease where previous other forms of therapy to palliate symptoms have been insufficient.

Isolated Polycystic Liver Disease: An Unusual Cause of Recurrent Variceal Bleed

Isolated polycystic liver disease is a rare disorder. Majority of the patients with isolated polycystic liver disease are asymptomatic with incidental detection of liver cysts on imaging studies done for other purposes. Minority of patients develop symptoms which are mostly secondary to enlarging cysts size and hepatomegaly. Rarely, these patients develop portal hypertension and can present with its clinical manifestations and consequences in the form acute variceal bleeding or recurrent ascites. We present a rare case of 67-year-old female patient with significant history of polycystic liver disease who presented to the hospital with recurrent hematemesis and melena. She underwent esophagogastroduodenoscopy which showed multiple large esophageal varices requiring banding.

An update on the pathophysiology and management of polycystic liver disease

Polycystic liver disease (PLD) is characterized by the presence of multiple cholangiocyte-derived hepatic cysts that progressively replace liver tissue. They are classified as an inherited ciliopathy /cholangiopathy as pathology exists at the level of the primary cilia of cholangiocytes. Aberrant expression of the proteins in primary cilia can impair their structures and functions, thereby promoting cystogenesis. Areas covered: This review begins by looking at the epidemiology of PLD and its natural history. It then describes the pathophysiology and corresponding potential treatment strategies for PLD. Expert commentary: Traditionally, therapies for symptomatic PLD have been limited to symptomatic management and surgical interventions. Such techniques are not completely effective, do not alter the natural history of the disease, and are linked with high rate of re-accumulation of cysts. As a result, there has been a push for drugs targeted at abnormal cellular signaling cascades to address deregulated proliferation, cell dedifferentiation, apoptosis and fluid secretion. Currently, the only available drug treatments that halt disease progression and improve quality of life in PLD patients are somatostatin analogues. Numerous preclinical studies suggest that targeting components of the signaling pathways that influence cyst development can ameliorate growth of hepatic cysts.

Overexpression of Aquaporin 1 on cysts of patients with polycystic liver disease

BACKGROUND AND OBJECTIVE

Polycystic liver disease (PCLD) represents a group of genetic disorders that include autosomal dominant polycystic kidney disease (ADPKD) and isolated polycystic liver disease (iPCLD). There is currently no definitive treatment except for liver transplantation. The aim of this study was to assess the expression level of aquaporin 1 (AQP1) on the PCLD cysts with different sizes and provide the potential therapeutic target.

METHODS

We collected 3 normal bile ducts, and recruited 8 patients with simple liver cyst disease, 24 patients with ADPKD, and 17 patients with iPCLD. AQP1 expression in different types of cyst walls and in normal bile ducts was detected using real time quantitative PCR, western blot and immunofluorescence staining. We also compared AQP1 expression levels in cysts of different sizes. Besides, ionic concentrations, pH and osmolality of cyst fluid were analyzed.

RESULTS

The results showed that AQP1 expression in PCLD cysts was significantly higher than that in simple liver cysts and the normal bile ducts. In addition, a comparable increasing trend was found in cysts of smaller sizes to cysts of larger sizes. pH values, the sodium and chloride concentrations were higher in cyst fluid than that in the serum.

CONCLUSIONS

AQP1 was overexpressed in cystic cholangiocytes. A tendency of increased AQP1 protein expression in correlation with the cyst size was also found. These observations offered a direction into the molecular mechanisms of cyst expansion and maybe provide new treatment strategies to reduce fluid secretion into liver cysts.

Portal hypertension in polycystic liver disease patients does not affect wait-list or immediate post-liver transplantation outcomes

AIM

To establish the impact of portal hypertension (PH) on wait-list/post-transplant outcomes in patients with polycystic liver disease (PCLD) listed for liver transplantation.

METHODS

A retrospective single-centre case controlled study of consecutive patients listed for liver transplantation over 12 years was performed from our centre. PH in the PCLD cohort was defined by the one or more of following parameters: (1) presence of radiological or endoscopic documented varices from our own centre or the referral centre; (2) splenomegaly (> 11 cm) on radiology in absence of splenic cysts accounting for increased imaging size; (3) thrombocytopenia (platelets < 150 × 10⁹/L); or (4) ascites without radiological evidence of hepatic venous outflow obstruction from a single cyst.

RESULTS

Forty-seven PCLD patients (F: M = 42: 5) were listed for liver transplantation (LT) (single organ, n = 35; combined liver-kidney transplantation, n = 12) with 19 patients (40.4%) having PH. When comparing the PH group with non-PH group, the mean listing age (PH group, 50.6 (6.4); non-PH group, 47.1 (7.4) years; P = 0.101), median listing MELD (PH group, 12; non-PH group, 11; P = 0.422) median listing UKELD score (PH group, 48; non-PH group, 46; P = 0.344) and need for renal replacement therapy (P = 0.317) were similar. In the patients who underwent LT alone, there was no difference in the duration of ICU stay (PH, 3 d; non-PH, 2 d; P = 0.188), hospital stay length (PH, 9 d; non-PH, 10 d; P = 0.973), or frequency of renal replacement therapy (PH, 2/8; non-PH, 1/14; P = 0.121) in the immediate post-transplantation period.

CONCLUSION

Clinically apparent portal hypertension in patients with PCLD listed for liver transplantation does not appear to have a major impact on wait-list or peri-transplant morbidity.

Evidence for a "Pathogenic Triumvirate" in Congenital Hepatic Fibrosis in Autosomal Recessive Polycystic Kidney Disease

Autosomal recessive polycystic kidney disease (ARPKD) is a severe monogenic disorder that occurs due to mutations in the PKHD1 gene. Congenital hepatic fibrosis (CHF) associated with ARPKD is characterized by the presence of hepatic cysts derived from dilated bile ducts and a robust, pericystic fibrosis. Cyst growth, due to cyst wall epithelial cell hyperproliferation and fluid secretion, is thought to be the driving force behind disease progression. Liver fibrosis is a wound healing response in which collagen accumulates in the liver due to an imbalance between extracellular matrix synthesis and degradation. Whereas both hyperproliferation and pericystic fibrosis are hallmarks of CHF/ARPKD, whether or not these two processes influence one another remains unclear. Additionally, recent studies demonstrate that inflammation is a common feature of CHF/ARPKD. Therefore, we propose a "pathogenic triumvirate" consisting of hyperproliferation of cyst wall growth, pericystic fibrosis, and inflammation which drives CHF/ARPKD progression. This review will summarize what is known regarding the mechanisms of cyst growth, fibrosis, and inflammation in CHF/ARPKD. Further, we will discuss the potential advantage of identifying a core pathogenic feature in CHF/ARPKD to aid in the development of novel therapeutic approaches. If a core pathogenic feature does not exist, then developing multimodality therapeutic approaches to target each member of the "pathogenic triumvirate" individually may be a better strategy to manage this debilitating disease.

Spontaneous rupture of non-parasitic or non-neoplastic multiple and giant liver cysts: report of a case

Simple liver cysts occasionally cause pressure symptoms of the abdomen. We herein report an extremely rare case of spontaneous rupture of simple liver cysts. A 65-year-old woman suffered abdominal fullness and dyspnea. Laboratory examinations revealed general inflammation and mild hepatorenal dysfunction. Computed tomography revealed giant polycystic liver and ascites. Echinococcus antibody was not detected. Abdominal paracentesis provided dark brown transparent ascites in which any parasites or tumor cells were not observed. We diagnosed spontaneous rupture of isolated polycystic liver disease (PCLD) and continuously drained the ascites. After the symptoms and laboratory data were improved, resection of liver cysts and left lateral segmentectomy were performed. Histopathologically, simple columnar epithelia inside of cyst walls were observed. The patient remains well without recurrence of the symptoms 10 months after the surgery. We reviewed characteristics of PCLD and considered appropriate treatment for spontaneous rupture of simple liver cysts based on the previous case reports including the present case.

Relationship of urinary endothelin-1 with estimated glomerular filtration rate in autosomal dominant polycystic kidney disease: a pilot cross-sectional analysis

Background

The pathogenesis of progressive renal insufficiency in autosomal dominant polycystic kidney disease (ADPKD) is unclear. Evidence from experimental models of ADPKD suggests that elevated endothelin-1 (ET-1) drives cyst growth, renal fibrosis and loss of renal function, but whether ET-1 is elevated in humans with ADPKD is uncertain.

Methods

In a cross-sectional study of ADPKD we measured urinary ET-1, a surrogate for ET-1 in kidney cortex, in spot collections corrected for creatinine. The volume of each kidney was measured using MRI-based stereology. The relationship of urine ET-1 with MDRD eGFR and kidney volume was modeled by multiple linear regression with adjustment for clinical covariates.

Results

Patients with ADPKD were ages 18 to 53 with eGFRs (median, interquartile range) of 63.2 (43.5–80.2) ml/min/1.73 m² and albumin/creatinine ratios (ACR) of 115.0 (7.5–58.5) μg/mg. Urine ET-1 was inversely associated with eGFR (r = −0.480, P < 0.05) and positively (r = 0.407, P = 0.066) with ACR independent of age and female sex (P < 0.01). ET-1 appeared to be positively associated with total kidney volume (r = 0.426, P = 0.100), with a test for trend across urine ET-1 quartiles yielding z = 1.83, P = 0.068. ET-1 strongly correlated with NAGase (r = 0. 687, P = 0.001), a marker of tubular damage and a surrogate marker of renal disease progression in ADPKD. Of note, ET-1 levels in urine were not correlated with hypertension.

Conclusions

In a translational study of patients with ADPKD, urinary ET-1 was inversely associated with eGFR and positively correlated with total kidney volume. Taken together with results from experimental models, these findings suggest that the role of ET-1 in ADPKD warrants further investigation.

Electronic supplementary material

The online version of this article (doi:10.1186/s12882-016-0232-8) contains supplementary material, which is available to authorized users.

Rare benign tumors of the liver: still rare?

Background

Benign liver tumors are common. They do not spread to other areas of the body, and they usually do not pose a serious health risk. In fact, in most cases, benign liver tumors are not diagnosed because patients are asymptomatic. When they are detected, it’s usually because the person has had medical imaging tests, such as an ultrasound (US), computed tomography (CT) scan, or magnetic resonance imaging (MRI), for another condition.

Materials and methods

A search of the literature was made using cancer literature and the PubMed, Scopus, and Web of Science (WOS) database for the following keywords: “hepatic benign tumors”, “hepatic cystic tumors”, “polycystic liver disease”, “liver macroregenerative nodules”, “hepatic mesenchymal hamartoma”, “hepatic angiomyolipoma”, “biliary cystadenoma”, and “nodular regenerative hyperplasia”.

Discussion and conclusion

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors in some areas of the world; there is an increasing incidence worldwide. Approximately 750,000 new cases are reported per year. More than 75 % of cases occur in the Asia-Pacific region, largely in association with chronic hepatitis B virus (HBV) infection. The incidence of HCC is increasing in the USA and Europe because of the increased incidence of hepatitis C virus (HCV) infection. Unlike the liver HCC, benign tumors are less frequent. However, they represent a chapter always more interesting of liver disease. In fact, a careful differential diagnosis with the forms of malignant tumor is often required in such a way so as to direct the patient to the correct therapy. In conclusion, many of these tumors present with typical features in various imaging studies. On occasions, biopsies are required, and/or surgical removal is needed. In the majority of cases of benign hepatic tumors, no treatment is indicated. The main indication for treatment is the presence of significant clinical symptoms or suspicion of malignancy or fear of malignant transformation.

ACG clinical guideline: the diagnosis and management of focal liver lesions

Focal liver lesions (FLL) have been a common reason for consultation faced by gastroenterologists and hepatologists. The increasing and widespread use of imaging studies has led to an increase in detection of incidental FLL. It is important to consider not only malignant liver lesions, but also benign solid and cystic liver lesions such as hemangioma, focal nodular hyperplasia, hepatocellular adenoma, and hepatic cysts, in the differential diagnosis. In this ACG practice guideline, the authors provide an evidence-based approach to the diagnosis and management of FLL.

Combined liver and kidney transplant in a patient with budd-Chiari syndrome secondary to autosomal dominant polycystic kidney disease associated with polycystic liver disease: report of a case with a 9-year follow-up

Polycystic liver disease (PLD) is a hereditary disease inherited by autosomal dominant trait that occurs as a frequent extrarenal manifestation of autosomal dominant polycystic kidney disease (ADPKD). We report a case of a 59-year-old woman diagnosed with ADPKD associated with PLD. End-stage chronic renal failure with a secondary Budd-Chiari syndrome developed during the patient's clinical course. She underwent combined liver and kidney transplantation, with a successful response over a 9-year follow-up period.

Polycystic liver disease: an overview of pathogenesis, clinical manifestations and management

Polycystic liver disease (PLD) is the result of embryonic ductal plate malformation of the intrahepatic biliary tree. The phenotype consists of numerous cysts spread throughout the liver parenchyma. Cystic bile duct malformations originating from the peripheral biliary tree are called Von Meyenburg complexes (VMC). In these patients embryonic remnants develop into small hepatic cysts and usually remain silent during life. Symptomatic PLD occurs mainly in the context of isolated polycystic liver disease (PCLD) and autosomal dominant polycystic kidney disease (ADPKD). In advanced stages, PCLD and ADPKD patients have massively enlarged livers which cause a spectrum of clinical features and complications. Major complaints include abdominal pain, abdominal distension and atypical symptoms because of voluminous cysts resulting in compression of adjacent tissue or failure of the affected organ. Renal failure due to polycystic kidneys and non-renal extra-hepatic features are common in ADPKD in contrast to VMC and PCLD. In general, liver function remains prolonged preserved in PLD. Ultrasonography is the first instrument to assess liver phenotype. Indeed, PCLD and ADPKD diagnostic criteria rely on detection of hepatorenal cystogenesis, and secondly a positive family history compatible with an autosomal dominant inheritance pattern. Ambiguous imaging or screening may be assisted by genetic counseling and molecular diagnostics. Screening mutations of the genes causing PCLD (PRKCSH and SEC63) or ADPKD (PKD1 and PKD2) confirm the clinical diagnosis. Genetic studies showed that accumulation of somatic hits in cyst epithelium determine the rate-limiting step for cyst formation. Management of adult PLD is based on liver phenotype, severity of clinical features and quality of life. Conservative treatment is recommended for the majority of PLD patients. The primary aim is to halt cyst growth to allow abdominal decompression and ameliorate symptoms. Invasive procedures are required in a selective patient group with advanced PCLD, ADPKD or liver failure. Pharmacological therapy by somatostatin analogues lead to beneficial outcome of PLD in terms of symptom relief and liver volume reduction.

Whole-exome sequencing reveals LRP5 mutations and canonical Wnt signaling associated with hepatic cystogenesis

Polycystic livers are seen in the rare inherited disorder isolated polycystic liver disease (PCLD) and are recognized as the most common extrarenal manifestation in autosomal dominant polycystic kidney disease. Hepatic cystogenesis is characterized by progressive proliferation of cholangiocytes, ultimately causing hepatomegaly. Genetically, polycystic liver disease is a heterogeneous disorder with incomplete penetrance and caused by mutations in PRKCSH, SEC63, PKD1, or PKD2. Genome-wide SNP typing and Sanger sequencing revealed no pathogenic variants in hitherto genes in an extended PCLD family. We performed whole-exome sequencing of DNA samples from two members. A heterozygous variant c.3562C > T located at a highly conserved amino acid position (p.R1188W) in the low density lipoprotein receptor-related protein 5 (LRP5) gene segregated with the disease (logarithm of odds score, 4.62) but was not observed in more than 1,000 unaffected individuals. Screening of LRP5 in a PCLD cohort identified three additional mutations in three unrelated families with polycystic livers (p.V454M, p.R1529S, and p.D1551N), again all undetected in controls. All variants were predicted to be damaging with profound structural effects on LRP5 protein domains. Liver cyst tissue and normal hepatic tissue samples from patients and controls showed abundant LRP5 expression by immunohistochemistry. Functional activity analyses indicated that mutant LRP5 led to reduced wingless signal activation. In conclusion, we demonstrate that germ-line LRP5 missense mutations are associated with hepatic cystogenesis. The findings presented in this study link the pathophysiology of PCLD to deregulation of the canonical wingless signaling pathway.

Polycystic liver disease

A widespread use of ultrasound (US) examination is contributing to an increase in the diagnosis of renal and hepatic cysts. However, the vast majority of these lesions are benign with an indolent course during the patient's lifespan. Adult polycystic kidney disease (APKD) is one of the most common diagnosed entities. APKD is a genetic disease defined by the presence of multiple kidney cysts, occasionally accompanied by hepatic cysts. The presence of hepatic cysts sparing kidneys is very rare and thereby must be assumed as a different clinical entity. This article describes a case of an exuberant hepatomegaly due to the presence of isolated multiple hepatic cysts without renal involvement.

Pathophysiology, epidemiology, classification and treatment options for polycystic liver diseases

Polycystic liver diseases (PLD) represent a group of genetic disorders in which cysts occur in the liver (autosomal dominant polycystic liver disease) or in combination with cysts in the kidneys (autosomal dominant polycystic kidney disease). Regardless of the genetic mutations, the natural history of these disorders is alike. The natural history of PLD is characterized by a continuous increase in the volume and the number of cysts. Both genders are affected; however, women have a higher prevalence. Most patients with PLD are asymptomatic and can be managed conservatively. Severe symptoms can affect 20% of patients who develop massive hepatomegaly with compression of the surrounding organs. Rrarely, patients with PLD suffer from acute complications caused by the torsion of hepatic cysts, intraluminal cystic hemorrhage and infections. The most common methods for the diagnosis of PLD are cross sectional imaging studies. Abdominal ultrasound and computerized tomography are the two most frequently used investigations. Magnetic resonance imaging is more sensitive and specific, and it is a valuable test for patients with intravenous contrast allergies or renal dysfunction. Different treatment modalities are available to physicians caring for these patients. Medical treatment has been ineffective. Percutaneous sclerotherapy, trans-arterial embolization, cyst fenestration, hepatic resection and liver transplantation are indicated to specific groups of patients and have to be tailored according to the extent of disease. This review outlines the current knowledge of the pathophysiology, clinical course, diagnosis and treatment strategies of PLD.

Evaluation of hepatic cystic lesions

Hepatic cysts are increasingly found as a mere coincidence on abdominal imaging techniques, such as ultrasonography (USG), computed tomography (CT) and magnetic resonance imaging (MRI). These cysts often present a diagnostic challenge. Therefore, we performed a review of the recent literature and developed an evidence-based diagnostic algorithm to guide clinicians in characterising these lesions. Simple cysts are the most common cystic liver disease, and diagnosis is based on typical USG characteristics. Serodiagnostic tests and microbubble contrast-enhanced ultrasound (CEUS) are invaluable in differentiating complicated cysts, echinococcosis and cystadenoma/cystadenocarcinoma when USG, CT and MRI show ambiguous findings. Therefore, serodiagnostic tests and CEUS reduce the need for invasive procedures. Polycystic liver disease (PLD) is arbitrarily defined as the presence of > 20 liver cysts and can present as two distinct genetic disorders: autosomal dominant polycystic kidney disease (ADPKD) and autosomal dominant polycystic liver disease (PCLD). Although genetic testing for ADPKD and PCLD is possible, it is rarely performed because it does not affect the therapeutic management of PLD. USG screening of the liver and both kidneys combined with extensive family history taking are the cornerstone of diagnostic decision making in PLD. In conclusion, an amalgamation of these recent advances results in a diagnostic algorithm that facilitates evidence-based clinical decision making.

Neuroendocrine tumor in the liver of a patient with isolated polycystic liver disease: A case report and review of the literature

Neuroendocrine tumors (NETs) frequently metastasize to the liver, but it is rare to find them there as primary tumors. Isolated polycystic liver disease (PCLD) is a rare autosomal dominant disease. There is no known association between polycystic liver disease and neuroendocrine or other tumors. We report a case of a 64-year-old female with a past medical history of isolated PCLD who presented with increasing abdominal pain over a two-week period. Our patient underwent open surgical biopsy one month after presentation. The histological examination and immunohistochemical findings suggested an intermediate grade neuroendocrine tumor. A 24-h delayed whole-body scintigraphy technique was utilized for the identification and localization of neuroendocrine tumors via the administration of In-111-labeled OctreoScan; however, no extrahepatic accumulation was observed. No previous studies in the literature describe a patient with PCLD and a primary or metastatic neuroendocrine tumor of the liver.

Diagnosis and management of polycystic liver disease

Polycystic liver disease (PLD) is arbitrarily defined as a liver that contains >20 cysts. The condition is associated with two genetically distinct diseases: as a primary phenotype in isolated polycystic liver disease (PCLD) and as an extrarenal manifestation in autosomal dominant polycystic kidney disease (ADPKD). Processes involved in hepatic cystogenesis include ductal plate malformation with concomitant abnormal fluid secretion, altered cell-matrix interaction and cholangiocyte hyperproliferation. PLD is usually a benign disease, but can cause debilitating abdominal symptoms in some patients. The main risk factors for growth of liver cysts are female sex, exogenous oestrogen use and multiple pregnancies. Ultrasonography is very useful for achieving a correct diagnosis of a polycystic liver and to differentiate between ADPKD and PCLD. Current radiological and surgical therapies for symptomatic patients include aspiration-sclerotherapy, fenestration, segmental hepatic resection and liver transplantation. Medical therapies that interact with regulatory mechanisms controlling expansion and growth of liver cysts are under investigation. Somatostatin analogues are promising; several clinical trials have shown that these drugs can reduce the volume of polycystic livers. The purpose of this Review is to provide an update on the diagnosis and management of PLD with a focus on literature published in the past 4 years.

Polycystic diseases in visceral organs

Primary cilia are nonmotile, microtubule-based, antenna-like organelles projecting from the apical surface of most mammalian cells. Elegant studies have established the importance of ciliary structure and function in signal transduction and the sensory roles of cilia in maintaining healthy cellular state. In particular, dysfunctional cilia have been implicated in a large number of diseases mainly characterized by the presence of fluid-filled cysts in various organs. Aside from polycystic kidney disease (PKD), however, the roles of cilia in polycystic liver disease (PLD), polycystic pancreas disease (PPD), and polycystic ovarian syndrome (PCOS) are still very vague. In addition, although gender and sex hormones are known to regulate cyst formation, their roles in regulating physiological functions of cilia need to be further explored.

Hepatorenal findings in obligate heterozygotes for autosomal recessive polycystic kidney disease

Autosomal recessive polycystic kidney disease (ARPKD), characterized by progressive cystic degeneration of the kidneys and congenital hepatic fibrosis (CHF), is the most common childhood onset ciliopathy, with an estimated frequency of 1 in 20,000 births. It is caused by mutations in PKHD1. The carrier frequency for ARPKD in the general population is estimated at 1 in 70. Given the recessive inheritance pattern, individuals who are heterozygous for PKHD1 mutations are not expected to have clinical findings. We performed ultrasound (USG) evaluations on 110 parents from 64 independent ARPKD families and identified increased medullary echogenicity in 6 (5.5%) and multiple small liver cysts in 10 parents (9%). All ARPKD parents with these abnormal imaging findings were asymptomatic; kidney and liver function tests were unremarkable. Complete sequencing of PKHD1 in the 16 ARPKD parents with abnormal imaging confirmed the mutation transmitted to the proband, but did not reveal any other pathogenic variants. Our data suggest that carrier status for ARPKD is a predisposition to polycystic liver disease and renal involvement associated with increased medullary echogenicity on USG. Whether some of these individuals become symptomatic as they age remains to be determined.

Systematic review: the pathophysiology and management of polycystic liver disease

BACKGROUND

Polycystic liver diseases (PCLD) represent a group of genetic disorders in which cysts occur solely in the liver, or together with renal cysts. Most of the patients with PCLD are asymptomatic, however, in some patients, expansion of liver cysts causes invalidating abdominal symptoms.

AIM

To provide a systemic review on the pathophysiology and management of PCLD.

METHODS

A PubMed search was undertaken to identify relevant literature using search terms including polycystic liver disease, pathophysiology, surgical and medical management.

RESULTS

The most common complication in patients with PCLD is extensive hepatomegaly, which may lead to malnutrition and can be lethal. Conservative surgical approaches are only partially effective and do not change the natural course of the disease. Liver transplantation has been successfully performed in PCLD, however, in an era of organ shortage, medical management needs to be evaluated. A better understanding of the pathophysiology and the availability of animal models have already identified promising drugs. Abnormalities in cholangiocyte proliferation/apoptosis and enhanced fluid secretion are key factors in the pathophysiology. It has been demonstrated in rodents and in humans that somatostatin analogues diminish liver volume. The role of the inhibitors of the mammalian target of rapamycin (mTOR) in the management of PCLD is still under investigation.

CONCLUSIONS

The exact pathophysiology of polycystic liver disease still remains unclear. In symptomatic patients, none of the currently available surgical options except liver transplantation have been shown to change the natural course of the disease. The use of somatostatin analogues has been shown to diminish liver volume.