Clinical management of polycystic liver disease

A 41-year old female underwent a computed tomography (CT) scan in 2010 because of symptoms suggestive of appendicitis. Incidentally, multiple liver lesions characterised as cysts were detected. The presence of small to medium sized liver cysts (diameter between <1 cm and 4 cm) in all liver segments (>100 cysts) and absence of kidney cysts in the context of normal renal function led to the clinical diagnosis of autosomal dominant polycystic liver disease (ADPLD). Five years later she was referred to the outpatient clinic with increased abdominal girth, pain in the right upper abdomen and right flank, and early satiety. She had difficulties bending over and could neither cut her toenails nor tie her shoe laces. In her early twenties she had used oral contraception for five years. She has been pregnant twice. Clinical examination showed an enlarged liver reaching into the right pelvic region and crossing the midline of the abdomen. Laboratory testing demonstrated increased gamma-glutamyl transferase (80 IU/L, normal <40 IU/L) and alkaline phosphatase (148 IU/L, normal <100 IU/L) levels. Bilirubin, albumin and coagulation times were within the normal range. A new CT scan in 2015 was compatible with an increased number and size of liver cysts. The diameter of cysts varied between <1 cm and 6 cm (anatomic distribution shown [Fig. 2B]). There were no signs of hepatic venous outflow obstruction, portal hypertension or compression on the biliary tract. Height-adjusted total liver volume (htTLV) increased from 2,667 ml/m in 2012 to 4,047 ml/m in 2015 (height 172 cm). The case we present here is not uncommon, and prompts several relevant questions.

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.

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.

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.

Results of percutaneous sclerotherapy and surgical treatment in patients with symptomatic simple liver cysts and polycystic liver disease

AIM: To evaluate the results of the treatment of simple liver cysts (solitary and multiple) and polycystic liver disease (PLD) using percutaneous sclerotherapy and/or surgical procedures in a single tertiary referral centre.

METHODS: Retrospective analysis of 54 patients referred for evaluation and possible treatment of simple liver cysts (solitary and multiple) and PLD, from January 1997 to July 2006.

RESULTS: Simple liver cysts were treated in 41 pts (76%) with a mean size of 12.6 cm. The most common reason for referral was abdominal pain or discomfort (85%). Percutaneous sclerotherapy was performed as initial treatment in 30 pts, showing cyst recurrence in 6 pts (20%). Surgical treatment was initially performed in 11 pts with cyst recurrence in 3 pts (27%). PLD was treated in 13 pts (24%) with a mean size of the dominant cyst of 13 cm. Percutaneous sclerotherapy for PLD was performed in 9 pts with recurrence in 7 pts (77.8%). Surgical treatment for PLD was undertaken in 4 pts (30.8%) with recurrence in all. Eventually, 2 pts with PLD in the presence of polycystic kidney disease underwent liver- and kidney transplantation because of deterioration of liver and kidney function.

CONCLUSION: The majority of patients with simple liver cysts and PLD are referred for progressive abdominal pain. As initial treatment, percutaneous sclerotherapy is appropriate. Surgical deroofing is indicated in case of cyst recurrence after percutaneous sclerotherapy. However, the results of percutaneous sclerotherapy and surgical treatment for PLD are disappointing. Partial liver resection is indicated when there is suspicion of a pre-malignant lesion.

Ursodeoxycholic acid in advanced polycystic liver disease: A phase 2 multicenter randomized controlled trial

BACKGROUND & AIMS

Ursodeoxycholic acid (UDCA) inhibits proliferation of polycystic human cholangiocytes in vitro and hepatic cystogenesis in a rat model of polycystic liver disease (PLD) in vivo. Our aim was to test whether UDCA may beneficially affect liver volume in patients with advanced PLD.

METHODS

We conducted an international, multicenter, randomized controlled trial in symptomatic PLD patients from three tertiary referral centers. Patients with PLD and total liver volume (TLV) ⩾2500ml were randomly assigned to UDCA treatment (15-20mg/kg/day) for 24weeks, or to no treatment. Primary endpoint was proportional change in TLV. Secondary endpoints were change in symptoms and health-related quality of life. We performed a post-hoc analysis of the effect of UDCA on liver cyst volume (LCV).

RESULTS

We included 34 patients and were able to assess primary endpoint in 32 patients, 16 with autosomal dominant polycystic kidney disease (ADPKD) and 16 with autosomal dominant polycystic liver disease (ADPLD). Proportional TLV increased by 4.6±7.7% (mean TLV increased from 6697ml to 6954ml) after 24weeks of UDCA treatment compared to 3.1±3.8% (mean TLV increased from 5512ml to 5724ml) in the control group (p=0.493). LCV was not different after 24weeks between controls and UDCA treated patients (p=0.848). However, UDCA inhibited LCV growth in ADPKD patients compared to ADPKD controls (p=0.049).

CONCLUSIONS

UDCA administration for 24weeks did not reduce TLV in advanced PLD, but UDCA reduced LCV growth in ADPKD patients. Future studies might explore whether ADPKD and ADPLD patients respond differently to UDCA treatment.

LAY SUMMARY

Current therapies for polycystic liver disease are invasive and have high recurrence risks. Our trial showed that the drug, ursodeoxycholic acid, was not able to reduce liver volume in patients with polycystic liver disease. However, a subgroup analysis in patients that have kidney cysts as well showed that liver cyst volume growth was reduced in patients who received ursodeoxycholic acid in comparison to patients who received no treatment. Trial registration number https://www.clinicaltrials.gov/: NCT02021110. EudraCT Number https://www.clinicaltrialsregister.eu/: 2013-003207-19.

Clinical response after laparoscopic fenestration of symptomatic hepatic cysts: a systematic review and meta-analysis

BACKGROUND

Laparoscopic fenestration is one of the treatment options for symptomatic hepatic cysts, either solitary or in context of polycystic liver disease (PLD), but indications, efficacy and surgical techniques are under debate.

METHODS

A systematic literature search (1950-2017) of PubMed, Embase, Web of Science and the Cochrane Library was performed (CRD42017071305). Studies assessing symptomatic relief or symptomatic recurrence after laparoscopic fenestration in patients with symptomatic, non-parasitic, hepatic cysts were included. Complications were scored according to Clavien-Dindo. Methodological quality was assessed by Newcastle-Ottawa scale (NOS) for cohort studies. Pooled estimates were calculated using a random effects model for meta-analysis.

RESULTS

Out of 5277 citations, 62 studies with a total of 1314 patients were included. Median NOS-score was 6 out of 9. Median follow-up duration was 30 months. Symptomatic relief after laparoscopic fenestration was 90.2% (95% CI 84.3-94.9). Symptomatic recurrence was 9.6% (95% CI 6.9-12.8) and reintervention rate was 7.1% (95% CI 5.0-9.4). Post-operative complications occurred in 10.8% (95% CI 8.1-13.9) and major complications in 3.3% (95% CI 2.1-4.7) of patients. Procedure-related mortality was 1.0% (95% CI 0.5-1.6). In a subgroup analysis of PLD patients (n = 146), symptomatic recurrence and reintervention rates were significantly higher with respective rates of 33.7% (95% CI 18.7-50.4) and 26.4% (95% CI 12.6-43.0). Complications were more frequent in PLD patients, with a rate of 29.3% (95% CI 16.0-44.5).

CONCLUSIONS

Laparoscopic fenestration is an effective procedure for treatment of symptomatic hepatic cysts with a low symptomatic recurrence rate. The symptomatic recurrence rate and risk of complications are significantly higher in PLD patients.

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.

Current management of noninfectious hepatic cystic lesions: A review of the literature

Nonparasitic hepatic cysts consist of a heterogeneous group of disorders, which differ in etiology, prevalence, and manifestations. With improving diagnostic techniques, hepatic cysts are becoming more common. Recent advancements in minimally invasive technology created a new Era in the management of hepatic cystic disease. Herein, the most current recommendations for management of noninfectious hepatic cysts are described, thereby discussing differential diagnosis, new therapeutic modalities and outcomes.

Rare cystic liver lesions: A diagnostic and managing challenge

Cystic formations within the liver are a frequent finding among populations. Besides the common cystic lesions, like simple liver cysts, rare cystic liver lesions like cystadenocarcinoma should also be considered in the differential diagnosis. Thorough knowledge of each entity’s nature and course are key elements to successful treatment. Detailed search in PubMed, Cochrane Database, and international published literature regarding rare cystic liver lesions was carried out. In our research are included not only primary rare lesions like cystadenoma, hydatid cyst, and polycystic liver disease, but also secondary ones like metastasis from gastrointestinal stromal tumors lesions. Up-to date knowledge regarding diagnosis and management of rare cystic liver lesions is provided. A diagnostic and therapeutic algorithm is also proposed. The need for a multidisciplinary approach by a team including radiologists and surgeons familiar with liver cystic entities, diagnostic tools, and treatment modalities is stressed. Patients with cystic liver lesions must be carefully evaluated by a multidisciplinary team, in order to receive the most appropriate treatment, since many cystic liver lesions have a malignant potential and evolution.

Genetics and mechanisms of hepatic cystogenesis

Polycystic liver disease (PLD) is a heterogeneous genetic condition. PKD1 and PKD2 germline mutations are found in patients with autosomal dominant polycystic kidney disease (ADPKD). Autosomal dominant polycystic liver disease (ADPLD) is associated with germline mutations in PRKCSH, SEC63, LRP5, and recently ALG8 and SEC61. GANAB mutations are found in both patient groups. Loss of heterozygosity of PLD-genes in cyst epithelium contributes to the development of hepatic cysts. A genetic interaction network is implied in hepatic cystogenesis that connects the endoplasmic glycoprotein control mechanisms and polycystin expression and localization. Wnt signalling could be the major downstream signalling pathway that results in hepatic cyst growth. PLD in ADPLD and ADPKD probably results from changes in one common final pathway that initiates cyst growth. This article is part of a Special Issue entitled: Cholangiocytes in Health and Diseaseedited by Jesus Banales, Marco Marzioni, Nicholas LaRusso and Peter Jansen.

The Association of Combined Total Kidney and Liver Volume with Pain and Gastrointestinal Symptoms in Patients with Later Stage Autosomal Dominant Polycystic Kidney Disease

BACKGROUND

There is an ongoing debate if and how kidney and liver volume are associated with pain and gastrointestinal (GI) symptoms in autosomal dominant polycystic kidney disease (ADPKD) patients. Since both kidney and liver volume could interact, we investigated whether combined total kidney and liver volume had stronger associations with ADPKD-related pain and GI symptoms than the volumes of the organs separately.

METHODS

We used baseline data from the DIPAK-1 study, which included ADPKD patients with an estimated glomerular filtration rate (eGFR) between 30 and 60 mL/min/1.73 m2. MR imaging was performed to measure height-adjusted total kidney volume (hTKV), height-adjusted total liver volume (hTLV) and the combination of both (height-adjusted total kidney liver volume [hTKLV]).

RESULTS

Three hundred nine ADPKD patients were included with a mean age of 48 ± 7 years, 53% female, eGFR 50 ± 11 mL/min/1.73 m2 and median hTKV, hTLV and hTKLV of 1,095 (758-1,669), 1,173 (994-1,523) and 2,496 (1,972-3,352) mL/m, respectively. ADPKD-related pain and GI symptoms were present in, respectively, 27.5 and 61.2% of patients. Gender was no effect modifier in the association between kidney and/or liver volume, and symptom burden, indicating that all models could be tested in the overall study population. hTKLV and hTLV were significantly associated with pain and GI symptoms, whereas hTKV was not. Model testing revealed that the associations of pain and GI symptoms with hTKLV were significantly stronger than with hTKV (p = 0.04 and p = 0.04, respectively) but not when compared to hTLV (p = 0.2 and p = 0.5, respectively).

CONCLUSIONS

This study indicates that combined kidney and liver volume was associated with the presence and severity of pain and GI symptoms in ADPKD, with a more prominent role for hTLV than for hTKV.

Epidemiology of autosomal-dominant polycystic liver disease in Olmsted county

Background & Aims

Isolated autosomal-dominant polycystic liver disease (ADPLD) is generally considered a rare disease. However, the frequency of truncating mutations to ADPLD genes in large, population sequencing databases is 1:496. With the increasing use of abdominal imaging, incidental detection of hepatic cysts and ADPLD has become more frequent. The present study was performed to ascertain the incidence and point prevalence of ADPLD in Olmsted County, MN, USA, and how these are impacted by the increasing utilisation of abdominal imaging.

Methods

The Rochester Epidemiology Project and radiology databases of Mayo Clinic and Olmsted Medical Center were searched to identify all subjects meeting diagnostic criteria for definite, likely, or possible ADPLD. Annual incidence rates were calculated using incident cases during 1980–2016 as numerator, and age- and sex-specific estimates of the population of Olmsted County as denominator. Point prevalence was calculated using prevalence cases as numerator, and age- and sex-specific estimates of the population of Olmsted County on 1 January 2010 as denominator.

Results

The incidence rate and point prevalence of combined definite and likely ADPLD were 1.01 per 100,000 person-years and 9.5 per 100,000 population, respectively. Only 15 of 35 definite and likely incident ADPLD cases had received a diagnostic code, and only 8 had clinically significant hepatomegaly. The incidence rates were much higher when adding possible cases, mainly identified through radiology databases, particularly in recent years and in older patients because of the increased utilisation of imaging studies.

Conclusions

Clinically significant isolated ADPLD is a rare disease with a prevalence <1:10,000 population. The overall prevalence of ADPLD, however, to a large extent not clinically significant, is likely much higher and closer to the reported genetic prevalence.

Lay summary

Isolated autosomal-dominant polycystic liver disease (ADPLD) is generally considered a rare disease. However, we demonstrate that it is a relatively common disease, which is rarely (<1:10,000 population) clinically significant.

•

Isolated autosomal-dominant polycystic liver disease (ADPLD) is generally considered a rare disease.

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Truncating mutations to ADPLD genes are fairly common (1:496) in large, population sequencing databases.

•

We identified 35 individuals meeting diagnostic criteria for definite or likely ADPLD and 99 additional patients with possible ADPLD.

•

The point prevalence of definite or likely ADPLD on 01/01/2010 was 9.5/100,000 or 36.0/100,000 population if adding possible cases.

•

Clinically significant isolated ADPLD is rare (<1:10,000 population), but the overall prevalence is likely much higher.

Total kidney and liver volume is a major risk factor for malnutrition in ambulatory patients with autosomal dominant polycystic kidney disease

Background

In patients with autosomal dominant polycystic kidney disease (ADPKD), malnutrition may develop as renal function declines and the abdominal organs become enlarged. We investigated the relationship of intra-abdominal mass with nutritional status.

Methods

This cross-sectional study was performed at a tertiary hospital outpatient clinic. Anthropometric and laboratory data including serum creatinine, albumin, and cholesterol were collected, and kidney and liver volumes were measured. Total kidney and liver volume was defined as the sum of the kidney and liver volumes and adjusted by height (htTKLV). Nutritional status was evaluated by using modified subjective global assessment (SGA).

Results

In a total of 288 patients (47.9% female), the mean age was 48.3 ± 12.2 years and the mean estimated glomerular filtration rate (eGFR) was 65.3 ± 25.3 mL/min/1.73 m². Of these patients, 21 (7.3%) were mildly to moderately malnourished (SGA score of 4 and 5) and 63 (21.7%) were at risk of malnutrition (SGA score of 6). Overall, patients with or at risk of malnutrition were older, had a lower body mass index, lower hemoglobin levels, and poorer renal function compared to the well-nourished group. However, statistically significant differences in these parameters were not observed in female patients, except for eGFR. In contrast, a higher htTKLV correlated with a lower SGA score, even in subjects with an eGFR ≥45 mL/min/1.73 m². Subjects with an htTKLV ≥2340 mL/m showed an 8.7-fold higher risk of malnutrition, after adjusting for age, hemoglobin, and eGFR.

Conclusions

Nutritional risk was detected in 30% of ambulatory ADPKD patients with relatively good renal function. Intra-abdominal organomegaly was related to nutritional status independently from renal function deterioration.

Electronic supplementary material

The online version of this article (doi:10.1186/s12882-016-0434-0) contains supplementary material, which is available to authorized users.

Predicting liver cyst severity by mutations in patients with autosomal-dominant polycystic kidney disease

BACKGROUND

Most patients with autosomal-dominant polycystic kidney disease (ADPKD) develop liver cysts and polycystic liver disease as they age. To date, no simple clinical indicator has been confirmed to predict polycystic liver disease exacerbation. Furthermore, the effect of the type and location of mutation on disease progression of polycystic liver disease remains unclear. Here, we aimed to establish a simple liver cyst indicator for clinical practice and investigate whether gene mutations determined liver phenotype in patients with autosomal-dominant polycystic kidney disease.

METHODS

In total, 129 patients with ADPKD were enrolled and liver cyst indicators were assessed based on mutation type (truncating mutation: nonsense, frameshift, and splicing mutation; non-truncating mutation: substitution) and mutation position. Liver cyst severity was determined using Gigot and Drenth classifications, based on their number, maximum diameter, and area ratio with the liver.

RESULTS

We observed an overall prevalence of 62.8% for polycystic liver disease. Patients with PKD1 nonsense mutations, a type of PKD1 truncating mutation, exhibited more severe liver disease phenotypes than those without the mutation. We identified maximum diameter as a potential liver cyst indicator. Moreover, a subgroup analysis that included a PKD1 nonsense mutation cohort revealed that genetic mutations located closer to the 5' end of PKD1 were associated with a maximum diameter index value ≥ 6 cm.

CONCLUSION

PKD1 nonsense mutations were associated with liver cyst severity, which along with maximum diameter index as a simple clinical indicator for liver cysts, may improve the treatment of polycystic liver disease associated with ADPKD.

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.

Predictors of treatment response following aspiration sclerotherapy of hepatic cysts: an international pooled analysis of individual patient data

OBJECTIVES

To identify predictive variables of treatment response following aspiration sclerotherapy of large symptomatic hepatic cysts.

METHODS

We collected individual patient data from two tertiary referral centres and included all patients treated with aspiration sclerotherapy of a large (>5 cm), symptomatic hepatic cyst. At six months, clinical response was defined as complete or incomplete. Secondary, suboptimal technical response was defined as lower quartile of cyst reduction. Predictive variables of clinical and technical response were analyzed by logistic regression analysis.

RESULTS

We included 86 patients (58 ± 10 years; female 90 %). Complete clinical response rate was 55 %. Median cyst diameter and volume reduction were 71 % (IQR 50-87 %) and 98 % (IRQ 88-100 %), respectively. Patients with complete clinical response had a significantly higher cyst reduction compared to incomplete responders (OR 1.02, 95 % CI 1.00-1.04). Aspiration of haemorrhagic cyst fluid (OR 4.39, 95 % CI 1.34-14.39) or a lower cyst reduction at one month (OR 1.06, 95 % CI 1.02-1.10) was associated with a suboptimal technical response at six months.

CONCLUSION

Complete clinical response is associated with effective cyst reduction. Aspiration of haemorrhagic cyst fluid or a restricted diameter reduction at one month predicts a suboptimal technical treatment response, however, these variables did not predict symptom disappearance.

KEY POINTS

• Aspiration sclerotherapy of hepatic cysts shows excellent clinical and technical efficacy. • Optimal clinical responders have a markedly higher cyst reduction. • Haemorrhagic aspirate and a strong fluid reaccumulation predict suboptimal cyst reduction.

Tolvaptan for the Treatment of Enlarged Polycystic Liver Disease

A 44-year-old Japanese woman with autosomal dominant polycystic kidney disease was admitted to our hospital for evaluation of abdominal distension. Her eGFR was 53.7 mL/min/1.73 m². Total kidney volume was 2,614 mL. Tolvaptan (60 mg/day) was started to treat renal involvement. The patient's abdominal fullness began to improve and liver volume, indicating advanced polycystic liver disease (PLD), decreased from 9,750 mL to 8,345 mL after 17 months of tolvaptan treatment, though there was no significant change in kidney volume. This case indicates that tolvaptan may be a therapeutic option for hepatomegaly in patients with symptomatic PLD.

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.

Novel GANAB variants associated with polycystic liver disease

BACKGROUND

Polycystic liver disease (PLD) is an inherited disorder characterized by numerous cysts in the liver. Autosomal dominant polycystic kidney and liver disease (ADPKD and ADPLD, respectively) have been linked to pathogenic GANAB variants. GANAB encodes the α-subunit of glucosidase II (GIIα). Here, we report the identification of novel GANAB variants in an international cohort of patients with the primary phenotype of PLD using molecular inversion probe analysis.

RESULTS

Five novel GANAB variants were identified in a cohort of 625 patients with ADPKD or ADPLD. In silico analysis revealed that these variants are likely to affect functionally important domains of glucosidase II α-subunit. Missense variant c.1835G>C p.(Arg612Pro) was predicted to disrupt the structure of the active site of the protein, likely reducing its activity. Frameshift variant c.687delT p.(Asp229Glufs*60) introduces a premature termination codon predicted to have no activity. Two nonsense variants (c.2509C>T; p.(Arg837*), and c.2656C>T; p.(Arg886*)) and splice variant c.2002+1G>C, which causes aberrant pre-mRNA splicing and affecting RNA processing, result in truncated proteins and are predicted to cause abnormal binding of α- and β-subunits of glucosidase II, thus affecting its enzymatic activity. Analysis of glucosidase II subunits in cell lines shows expression of a truncated GIIα protein in cells with c.687delT, c.2509C>T, c.2656C>T, and c.2002+1G>C variants. Incomplete colocalization of the subunits was present in cells with c.687delT or c.2002+1G>C variants. Other variants showed normal distribution of GIIα protein.

CONCLUSIONS

We identified five novel GANAB variants associated with PLD in both ADPKD and ADPLD patients supporting a common pathway in cystogenesis. These variants may lead to decreased or complete loss of enzymatic activity of glucosidase II which makes GANAB a candidate gene to be screened in patients with an unknown genetic background.

An in vitro model of polycystic liver disease using genome-edited human inducible pluripotent stem cells

In the developing liver, bile duct structure is formed through differentiation of hepatic progenitor cells (HPC) into cholangiocytes. A subtype of polycystic liver diseases characterized by uncontrolled expansion of bile ductal cells is caused by genetic abnormalities such as in that of protein kinase C substrate 80 K-H (PRKCSH). In this study, we aimed to mimic the disease process in vitro by genome editing of the PRKCSH locus in human inducible pluripotent stem (iPS) cells. A proportion of cultured human iPS cell-derived CD13+CD133+ HPC differentiated into CD13- cells. During the subsequent gel embedding culture, CD13- cells formed bile ductal marker-positive cystic structures with the polarity of epithelial cells. A deletion of PRKCSH gene increased expression of cholangiocytic transcription factors in CD13- cells and the number of cholangiocytic cyst structure. These results suggest that PRKCSH deficiency promotes the differentiation of HPC-derived cholangiocytes, providing a good in vitro model to analyze the molecular mechanisms underlying polycystic diseases.

An update on ductal plate malformations and fibropolycystic diseases of the liver

A variety of cystic and fibrocystic lesions can occur in the liver, which may be single or multiple and etiologically can be acquired or have genetic underpinnings. Although the morphology of ductal plate development and various associated malformations has been well described, the genetic etiologies of many of these disorders are still poorly understood. Multiple clinical phenotypes in the liver are proposed to originate from ductal plate malformations: congenital hepatic fibrosis, Caroli's disease, Von Meyenburg complex, and the liver cysts of autosomal dominant polycystic kidney and liver diseases. Although many of the patients with these disorders, particularly with isolated liver involvement remain asymptomatic, some develop portal hypertension or symptoms from cyst enlargement. Development of hepatocellular malignancy is a risk in a small subset. Recent advances have made it now possible for some of these phenotypes to be genetically defined, and intriguingly animal models of adult polycystic liver disease suggest that abnormal organ development is not required. This review describes the current understanding, genetic underpinning, and key clinicopathologic and imaging features of these fibropolycystic liver diseases.

Comparison of MRI segmentation techniques for measuring liver cyst volumes in autosomal dominant polycystic kidney disease

PURPOSE

To compare MRI segmentation methods for measuring liver cyst volumes in autosomal dominant polycystic kidney disease (ADPKD).

METHODS

Liver cyst volumes in 42 ADPKD patients were measured using region growing, thresholding and cyst diameter techniques. Manual segmentation was the reference standard.

RESULTS

Root mean square deviation was 113, 155, and 500 for cyst diameter, thresholding and region growing respectively. Thresholding error for cyst volumes below 500ml was 550% vs 17% for cyst volumes above 500ml (p<0.001).

CONCLUSION

For measuring volume of a small number of cysts, cyst diameter and manual segmentation methods are recommended. For severe disease with numerous, large hepatic cysts, thresholding is an acceptable alternative.

Expanding the variability of the ADPKD-GANAB clinical phenotype in a family of Italian ancestry

BACKGROUND

Causative mutations in the GANAB gene have been described in only 14 families, 9 diagnosed with late-onset Autosomal Dominant Polycystic Kidney Disease (ADPKD) and 5 with Autosomal Dominant Polycystic Liver Disease (ADPLD).

CASE

Diagnosis of ADPKD was made in a 45-year old man during screening for hernia repair. CT scan showed enlarged cystic kidneys, nephrolithiasis and normal-sized liver with multiple cysts. Hematuria, hypertension and aortic root dilatation were also documented. Renal function was normal. Molecular analysis of PKD genes disclosed a heterozygous p.R839W GANAB variant inherited from the mother. Both his elderly parents presented normal-sized bilateral cystic kidneys but normal renal function. The GANAB-ADPKD mother had no liver cysts. The father was screened for PKD-related genes and no variant was found.

GENETIC ANALYSIS

We describe a new family with late-onset ADPKD due to the p.R839W GANAB variant, previously reported in a severe ADPLD patient, requiring liver transplantation.

DISCUSSION

Since ADPKD-GANAB is an ultrarare, recently described disease, reporting further patients may help unraveling gene-related phenotype. In our patients the p.R839W GANAB variant was not related to severe ADPLD, as previously reported, but with mild ADPKD and a plethora of renal and extrarenal manifestations, usually described in PKD1/PKD2 patients. The evidence that the GANAB variant may cause both ADPKD and ADPLD of variable severity supports that renal and hepatic cystogenesis are the result of a common defective polycystin-1 pathway.

Obstructive jaundice in polycystic liver disease related to coexisting cholangiocarcinoma

Although jaundice rarely complicates polycystic liver disease (PLD), secondary benign or malignant causes cannot be excluded. In a 72-year-old female who presented with increased abdominal girth, dyspnea, weight loss and jaundice, ultrasound and computed tomography confirmed the diagnosis of PLD by demonstrating large liver cysts causing extrahepatic bile duct compression. Percutaneous cyst aspiration failed to relief jaundice due to distal bile duct cholangiocarcinoma, suspected by magnetic resonance cholangiopancreatography (MRCP) and confirmed by endoscopic retrograde cholangiopancreatography (ERCP). Coexistence of PLD with distal common bile duct cholangiocarcinoma has not been reported so far.