Caroli's disease: Liver resection and liver transplantation. Experience in 33 patients

Safety and benefit of modified mesohepatectomy in the treatment of bilobar involvement congenital biliary dilatation

BACKGROUND

The diseased bile duct in bilobar congenital biliary dilatation is extensive and often requires major hepatectomy or liver transplantation associated with a higher risk. We aimed to evaluate the safety and benefit of modified mesohepatectomy, in comparison with trisectionectomy, to treat bilobar congenital biliary dilatation.

METHODS

This study included 28 patients with type IV and V bilobar congenital biliary dilatation. An innovative mesohepatectomy comprising the hepatectomy technique beyond the P/U point and bile duct shaping was applied to 14 patients to address the extensively diseased bile duct and difficulty in hepaticojejunostomy. Another 14 patients received trisectionectomy. The perioperative and long-term outcomes of these patients were compared.

RESULTS

The ratio of residual liver volume to standard liver volume in the mesohepatectomy group was higher (78.68% vs. 40.90%, p = 0.005), while the resection rate of the liver parenchyma was lower (28.25% vs. 63.97%, p = 0.000), than that in trisectionectomy group. The mesohepatectomy group had a lower severe complication (>Clavein III, 0% vs. 57.70%, p = 0.019) and incidence of posthepatectomy liver failure (7.14% vs. 42.86%, p = 0.038). No significant difference was observed in blood loss and bile leakage (p > 0.05). All the patients in the mesohepatectomy group achieved optimal results in the long-term follow-up.

CONCLUSIONS

mesohepatectomy provides an efficient treatment option for bilobar congenital biliary dilatation and can achieve radical resection, retain more liver parenchyma, and reduce the difficulty of hepaticojejunostomy, especially for patients that are not eligible for major hepatectomy and liver transplantation.

Exceptional Liver Transplant Indications: Unveiling the Uncommon Landscape

Liver transplantation represents the definitive intervention for various etiologies of liver failure and encompasses a spectrum of rare indications crucial to understanding the diverse landscape of end-stage liver disease, with significantly improved survival rates over the past three decades. Apart from commonly encountered liver transplant indications such as decompensated cirrhosis and liver cancer, several rare diseases can lead to transplantation. Recognition of these rare indications is essential, providing a lifeline to individuals facing complex liver disorders where conventional treatments fail. Collaborative efforts among healthcare experts lead not only to timely interventions but also to the continuous refinement of transplant protocols. This continued evolution in transplant medicine promises hope for those facing diverse and rare liver diseases, marking a paradigm shift in the landscape of liver disease management.

Right hepatectomy with a cholangiojejunostomy and hepaticojejunostomy for unilobar Caroli's syndrome

Caroli...s syndrome is a rare entity. It is characterized by multi-cystic dilatation of intrahepatic bile ducts with congenital hepatic fibrosis. Here we describe a 43-year-old female with unilobar Carolis syndrome presented recurrent episodes of cholangitis. She subsequently had a right hepatectomy and complex bilio-enteric anastomoses which included a cholangiojejunostomy. This case illustrates a safe and novel surgical strategy employed to manage a patient with unilobar Caroli...s syndrome.

Liver transplantation for biliary cysts: perioperative and long-term outcomes

BACKGROUND

Biliary cysts (BC) is a rare indication for orthotopic liver transplantation (OLT).

METHODS

We queried the UNOS dataset to identify patients who underwent OLT for Caroli's disease (CD) and choledochal cysts (CC). All patients with BC (CD + CC) were compared to a cohort of patients transplanted for other indications. Patients with CC were also compared to those with CD. Cox proportional hazard model was performed to assess predictors of graft and patient survival.

RESULTS

261 patients underwent OLT for BC. Patients with BC had better pre-operative liver function compared to those transplanted for other indications. 5-year graft and patient survival were 72% and 81%, respectively, similar to those transplanted for other indications after matching. Patients with CC were younger and had increased preoperative cholestasis compared to those with CD. Donor age, race, and gender were predictors of poor graft and patient survival in patients transplanted for CC.

CONCLUSIONS

Patients with BC have similar outcomes to those transplanted for other indications and more frequently require MELD score exception. In patients transplanted for choledochal cysts, female gender, donor age, and African-American race were independent predictors of poor survival. Pediatric patients transplanted for Caroli's disease had better survival compared to adults.

Diagnosis and management of choledochal cysts

BACKGROUND

Choledochal cysts (CCs) are rare cystic dilatations of the intrahepatic and/or extrahepatic bile ducts. We review the pathophysiology, diagnosis, and management of CCs.

METHODS

MEDLINE/PubMed and Web of Science databases were queried for "choledochal cyst", "bile duct cyst", "choledochocele", and "Caroli disease". Data were synthesized and systematically reviewed.

RESULTS

Classified according to the Todani Classification, CCs are generally believed to arise secondary to reflux of pancreatic enzymes into the biliary tree due to anomalous pancreaticobiliary duct union. Complications of CCs include abdominal pain, jaundice, cystolithiasis, cholecystitis, pancreatitis, liver abscess, liver cirrhosis and malignant transformation (3-7.5%). Radiological and endoscopic imaging is the cornerstone of CC diagnosis and full delineation of cyst anatomy is imperative for proper management. Management is generally guided by cyst classification with complete cyst excision necessary for CCs with high potential of malignant transformation such as types I and IV. 5-year overall survival after choledochal cyst excision is 95.5%.

CONCLUSION

Most CCs should undergo surgical intervention to mitigate the risk of cyst related complications such as cholangitis and malignant transformation.

EASL Clinical Practice Guidelines on the management of cystic liver diseases

The advent of enhanced radiological imaging techniques has facilitated the diagnosis of cystic liver lesions. Concomitantly, the evidence base supporting the management of these diseases has matured over the last decades. As a result, comprehensive clinical guidance on the subject matter is warranted. These Clinical Practice Guidelines cover the diagnosis and management of hepatic cysts, mucinous cystic neoplasms of the liver, biliary hamartomas, polycystic liver disease, Caroli disease, Caroli syndrome, biliary hamartomas and peribiliary cysts. On the basis of in-depth review of the relevant literature we provide recommendations to navigate clinical dilemmas followed by supporting text. The recommendations are graded according to the Oxford Centre for Evidence-Based Medicine system and categorised as 'weak' or 'strong'. We aim to provide the best available evidence to aid the clinical decision-making process in the management of patients with cystic liver disease.

The rate of cholangiocarcinoma in Caroli Disease A German multicenter study

BACKGROUND

Caroli Disease (CD) and Caroli Syndrome (CS) are rare disorders presenting with dilation of the intrahepatic bile ducts. CD/CS are associated with cholangiocarcinoma (CCA). However, the true incidence of CCA is still unclear, although it may serve as an indication for surgery. In this paper, we analyzed (I) the incidence of CCA in German centers, (II) reviewed our single center population together with its clinical presentation and (III) performed a thorough literature review.

METHODS

17 large HPB-centers across Germany were contacted and their patients after surgical treatment due to CD/CS with histopathology were included. Medline search for all studies published in English or German literature was performed. Patients who underwent surgery at our department between 2012 and 2020 due to CD or CS were analyzed.

RESULTS

In the multicenter study, 79 patients suffered from CD and 119 patients from CS, with a total number of 198 patients. In 14 patients, CCA was found (Overall: 7,1%; CD: 6,3%, CS 7,6%). Between 2012 and 2020, 1661 liver resections were performed at our department. 14 patients underwent surgery due to CD or CS. Histological examination showed synchronous cholangiocarcinoma in one patient. The literature review revealed a CCA-rate of 7,3% in large series, whereas in case reports a rate of 6,8% was found.

CONCLUSION

There is risk of malignant transformation and patients with CD might also benefit from resection due to improvement of symptoms. Therefore, resection is strongly advised. As certain patients with CS require transplantation, treatment should not be guided by the relatively low rate of CCA but by the concomitant diseases that come along with hepatic failure.

Canine hepatobiliary anatomy, physiology and congenital disorders

The biliary system is an integral component of normal physiologic homeostasis and essential for survival. It acts as a conduit for the removal of detoxified and catabolised compounds as well as aids in fat digestion and absorption. Derangements in this system can have dangerous sequela that are associated with varying degrees of morbidity and mortality. Moreover, abnormalities in development of the biliary system can have varied and unpredictable changes on function and long-term outcome. The aims of this article were to review canine hepatobiliary anatomy, physiology and cholestasis as well as summarise congenital biliary disorders including human corollaries.

Liver transplantation for rare liver diseases and rare indications for liver transplant

Liver transplantation (LT) is currently considered the gold standard treatment for end-stage liver failure. Compared to the first decades of its use, LT is associated with lower comorbidity and mortality, with a 5-year survival over 70%. Worldwide, liver cirrhosis and hepatocellular carcinoma represent the major indications to LT. However, almost 1% of LT is performed for rare diseases or rare indications, which include non-hepatocellular malignancy, vascular disorders, metabolic and congenital liver disorders. These diseases can lead to hepatocellular necrosis, biliary tree abnormality and/or hepatomegaly. Most of these diseases are not associated with liver failure but in highly selected patients, LT represent an effective therapy improving the overall survival and quality of life. Rare indications for LT often overlap with rare diseases. However, rare LT indications for non-rare diseases are rising in the last decades, especially for benign primary liver tumor, colon rectal liver metastasis, neuroendocrine liver metastasis, and cholangiocarcinoma (CCA). Non-rare diseases with rare indication for LT and rare adult disease with an indication for LT are categorized and discussed in detail, focusing on some disorders for which the literature provides a more definitive evidence base. Early referral to a transplant center is encouraged to provide an effective therapeutic option in these non-standard indications for LT.

Laparoscopic liver resection in Caroli disease: A single-centre case series

Background:

Liver resection is the treatment of choice for patients with localised Caroli disease. While liver resection was traditionally performed as open procedure, this case series aims to evaluate the safety and efficacy of minimally invasive, laparoscopic liver surgery in these patients.

Methods:

A systematic review of electronic case files of patients seen between April 2015 and December 2017 at the Department of Surgery, Charité University Hospital Berlin, was conducted. Patients with Caroli disease in whom laparoscopic liver resection had been performed were identified and analysed in this single-centre case series.

Results:

Seven patients who underwent laparoscopic liver surgery for Caroli syndrome were identified and presented with a median age of 49 (range = 44–66) years, of which four (57%) were female. Preoperatively, six patients were classified as the American Society of Anaesthesiologists (ASA) 2 and one patient as ASA 3. Two operations were performed as single-incision laparoscopic surgery, whereas the others were done as multi-incision laparoscopic surgery. One patient required a conversion to an open procedure. The length of operation varied between patients, ranging from 128 to 758 min (median = 355). The length of stay in the intensive care unit ranged from 0 to 2 days. Two patients presented with post-operative complications (Clavien–Dindo Grade ≥3a), whereas no patient died. In histopathological analysis, all patients demonstrated characteristic findings of Caroli disease and no cholangiocarcinoma was found.

Conclusion:

These results indicate that minimally invasive, laparoscopic liver surgery is a safe and efficacious treatment option for patients with Caroli disease who require liver resection.

Portal hypertension: An uncommon presentation of Caroli's syndrome

Portal hypertension is not a classical presentation of Caroli's syndrome. However, some young children can present with overt signs and symptoms indicative of advanced disease state despite the improvement in imaging technology which has decreased its diagnostic age. High index of clinical suspicion can help in timely diagnosis and management.

Factors contributing to diagnostic delay of Caroli syndrome: a single-center, retrospective study

Background

Caroli syndrome (CS) is a rare congenital disorder without pathognomonic clinical symptoms or laboratory findings; therefore, the diagnosis is often delayed. The objective of this study was to investigate the diagnostic delay and associated risk factors in CS patients.

Methods

This was a retrospective analysis of 16 CS patients admitted to a single tertiary medical center on mainland China. The diagnostic timelines of CS patients were reviewed to demonstrate the initial findings of CS at diagnosis, the risk factors associated with diagnostic delay, and potential clues leading to early diagnosis.

Results

The median diagnostic delay was 1.75 years (range: 1 month to 29 years, interquartile range: 6.2 years) in 16 enrolled CS patients. Sex, age, and initial symptoms were not associated with diagnostic delay. 87.5% of CS patients were diagnosed by imaging, and the accuracies of ultrasonography, computed tomography (CT), and magnetic resonance cholangiopancreatography were 25, 69.2, and 83.3%, respectively. The median diagnostic delays for patients with or without CT performed at the first hospital visited according to physician and radiologist suspicion of the diagnosis were 7.4 months and 6 years, respectively (p = 0.021). Hepatic cysts with splenomegaly were detected by ultrasound in over half of CS patients.

Conclusions

The majority of CS patients were not diagnosed until complications of portal hypertension had already developed. Recognition and early suspicion of the disease were important factors influencing diagnostic delay of CS. Hepatic cysts plus splenomegaly detected by US might raise the clinical suspicion to include CS in the differential diagnosis.

Risk of malignancy in Caroli disease and syndrome: A systematic review

BACKGROUND

Congenital intrahepatic bile duct dilatation without fibrosis is called Caroli disease (CD), and is called Caroli syndrome (CS) when it has fibrotic and cirrhotic liver morphology. The development of intrahepatic carcinoma is described in both conditions, but the reported incidence varies extensively. Potential risk factors for the malignant transformation were not described. Furthermore, conservative or surgical treatment is performed depending on the extent of cystic malformation, hepatic dysfunction and structural hepatic changes, but little is known about which treatment should be offered to patients with CD or CS and cancer.

AIM

To further investigate the malignant transformation in these conditions.

METHODS

A systematic review of the current literature until January 2019 was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. A search using Medline (PubMed) was performed using a combination of Medical Subject Headings terms “caroli disease”, “caroli syndrome”, “tumor”, “malignant”, and “cholangiocarcinoma”. Only human studies published in English were used for this systematic review. The following parameters were extracted from each article: year of publication, type of study, number of patients, incidence of malignant tumor, duration of symptoms, age, sex, diagnostics, identification of tumor, surgical therapy, survival and tumor recurrence.

RESULTS

Twelve retrospective studies reporting the courses of 561 patients (53% females) were included in this systematic review. With a mean age of 41.6 years old (range 23 to 56 years old), patients were younger than other populations undergoing liver surgery. Depending on the size of the study population the incidence of cholangiocarcinoma varied from 2.7% to 37.5% with an overall incidence of 6.6%. There were only few detailed reports about preoperative diagnostic work-up, but a multimodal work-up including ultrasound of the liver, computed tomography, magnetic resonance imaging and endoscopic retrograde cholangiopancreatography was used in most studies. Disease duration was variable with up to several years. Most patients had episodes of cholangitis, sepsis, fever or abdominal pain. Tumor detection was an incidental finding of the surgical specimen in most cases because it is currently often impossible to detect tumor manifestation during preoperative diagnostics. Liver resection or liver transplantation was performed depending on the extent of the biliary pathology and additional alterations of the liver structure or function. No postoperative adjuvant chemotherapy was reported, but chemotherapy was administered in selected cases of tumor recurrence. Overall survival rates after one year were low at 36% and a high recurrence rate of up to 75% during the observation period.

CONCLUSION

Only few retrospective studies reported a low tumor incidence. Despite the high rate of mortality and tumor recurrence, definite surgical treatment should be offered as soon as possible.

Endoscopic therapy for gastro-oesophageal varices of Caroli's syndrome: a case report

Caroli’s disease (CD) is a very rare congenital disorder that is characterized by non-obstructive, segmental and cystic dilatation of intrahepatic ducts. Most patients with CD are asymptomatic, but some patients may suffer from hepatic fibrosis, liver cirrhosis or/and portal hypertension. In complex CD, cystic dilatations of the intrahepatic bile ducts can be present with congenital hepatic fibrosis, liver cirrhosis, portal hypertension, oesophageal varices and autosomal recessive polycystic kidney disease; a condition known as Caroli’s syndrome. This report describes the case of a 28-year-old woman that had gastro-oesophageal varices that were caused by hepatic fibrosis and portal hypertension as part of Caroli’s syndrome. The patient underwent successful treatment with endoscopic injection sclerotherapy with lauromacrogol and endoscopic variceal obturation using tissue adhesive. There were no immediate complications and the patient remained free of complications at 1-year follow-up. There are no current reports in the published literature describing Caroli’s syndrome induced by gastro-oesophageal varices that were treated by a combination of endoscopic injection sclerotherapy and endoscopic variceal obturation. Endoscopic therapy was an effective technique for the treatment of gastro-oesophageal varices in a patient with Caroli’s syndrome awaiting a liver transplant.

Liver resection and transplantation in Caroli disease and syndrome

INTRODUCTION

Caroli disease (CD) is a congenital dilatation of the intrahepatic bile ducts. In combination with liver fibrosis or cirrhosis, it is called Caroli syndrome (CS). Infectious complications and intrahepatic cholangiocarcinoma are secondary problems. The aim of this study was to analyse the clinical pattern and outcome in patients with CD/CS who underwent liver surgery.

METHODS

Between January 2004 and December 2016, 21 patients with CD/CS were treated with liver resection or transplantation (LTX) and post-operative data of patients with CD/CS were retrospectively analysed in a database.

RESULTS

Two patients underwent LTX, and 19 patients underwent liver resection due to CD/CS. During follow-up, one patient developed lung cancer nine years after LTX. Patients resected due to CD/CS were predominantly females (74%) with an overall low incidence of co-morbidities. The median post-operative Clavien-Dindo score was 1 (range: 0-3). There was no death during a median follow-up period of over five years. In four patients, cholangiocarcinoma was confirmed. Tumor recurrence was seen in three patients, and was treated with chemotherapy or repeated liver resection.

CONCLUSIONS

LTX and liver resections due to CD/CS are rare and associated with an acceptable post-operative morbidity and low mortality. Surgical treatment should be performed as early as possible to avoid recurrent episodes of cholangitis or carcinogenesis.

Caroli's Disease as a Cause of Chronic Epigastric Abdominal Pain: Two Case Reports and a Brief Review of the Literature

Caroli's disease is a very rare congenital malformation, currently included in cystic diseases of the biliary tract, and is characterized by ectasia and dilatation of the intrahepatic bile ducts. Two clinical entities can be distinguished, Caroli's disease in which congenital hepatic impairment is limited to cystic dilatation and Caroli's syndrome in which congenital hepatic fibrosis coexists. We present two cases of atypical presentations of Caroli's disease. Case one was a 76-year-old man who was referred to our hospital for chronic non-remitting epigastric pain prior to diagnosis. Magnetic resonance cholangiopancreatography (MRCP) was performed, which revealed findings consistent with Caroli's disease. Laboratory investigation disclosed a raised α-fetoprotein. Left hepatectomy was performed due to suspected cholangiocarcinoma. Morphological findings were compatible with Caroli's disease and no evidence of malignancy was found. Case two was a 47-year-old man who presented with chronic epigastric pain and generalized abdominal discomfort. MRCP revealed findings compatible with Caroli's disease. The patient was discharged with ursodeoxycholic acid treatment and was later admitted twice due to inaugural episodes of cholangitis that were medically managed. Bisegmentectomies II and III were performed for suspected neoplasia after a gradual rise in α-fetoprotein and CA19-9 values were noted during follow-up. The surgical specimen confirmed Caroli's disease and there was no evidence of malignancy. Postoperative periods for both patients were favorable, and they remain asymptomatic and well to date.

Epidemiology and Risk Factors of Cholangiocarcinoma

BACKGROUND

Cholangiocarcinoma (CCA) is the second most common primary liver cancer, being characterized by its late diagnosis and fatal outcome. Recent epidemiological reports indicate an increasing worldwide incidence of intrahepatic CCA but a decreasing incidence of extrahepatic CCA.

METHODS

In this review, we present an overview of the incidence and epidemiology of CCA and possible strategies for screening and surveillance.

RESULTS

Efficient strategies for the screening and surveillance of CCA have not been established so far. The vast majority of CCA occur sporadically without any apparent cause; however, several risk factors such as liver flukes, chronic biliary and liver diseases, and lifestyle-related aspects causing chronic inflammation and cholestasis in the liver have been linked to the development of CCA. These risk factors likely contribute to the increased incidence observed in some countries and also explain the wide geographical differences in the incidence of CCA.

CONCLUSION

Several risk factors for CCA have been identified. Given the dismal prognosis of advanced CCA, regular surveillance examinations with a combination of ultrasonography and laboratory tests appear to be useful in patients at risk and need to be explored in prospective trials.

Recurrent Cholangitis in a Patient with Autosomal Dominant Polycystic Kidney Disease (ADPKD) and Caroli's Disease

We herein present a rare case of an autosomal dominant polycystic kidney disease (ADPKD) patient with Caroli's disease, a congenital embryonic biliary tree ductal plate abnormality often associated with autosomal recessive polycystic kidney disease. A 76-year-old woman with ADPKD on hemodialysis was admitted to our hospital with recurrent cholangitis and hepatobiliary stones. Caroli's disease was diagnosed according to typical imaging findings of cystic intrahepatic bile duct dilatation and the central dot sign. Hepatobiliary system abnormalities such as Caroli's disease should be considered in febrile ADPKD patients, even in the absence of typical clinical signs or symptoms.

Liver Resection for Primary Intrahepatic Stones: Focus on Postoperative Infectious Complications

BACKGROUND

Primary intrahepatic lithiasis is defined by the presence of gallstones at the level of cystic dilatations of the intrahepatic biliary tree. Liver resection is considered the treatment of choice, with the purpose of removing stones and atrophic parenchyma, also reducing the risk of cholangiocarcinoma. However, in consequence of the considerable incidence of infectious complications, postoperative morbidity remains high. The current study was designed to evaluate the impact of preoperative bacterial colonization of the bile ducts on postoperative outcome.

METHODS

The clinical records of 73 patients treated with liver resection were reviewed and clinical data, operative procedures, results of bile cultures, and postoperative outcomes were examined.

RESULTS

Left hepatectomy (38 patients) and left lateral sectionectomy (19 patients) were the most frequently performed procedures. Overall morbidity was 38.3 %. A total of 133 microorganisms were isolated from bile. Multivariate analysis identified previous endoscopic or percutaneous cholangiography (p = 0.043) and preoperative cholangitis (p = 0.003) as the only two independent risk factors for postoperative infectious complications.

CONCLUSIONS

Postoperative morbidity was strictly related to the preoperative biliary infection. An effective control of infections should be always pursued before liver resection for intrahepatic stones and an aggressive treatment of early signs of sepsis should be strongly emphasized.

Choledochal Cyst Disease in a Western Center: A 30-Year Experience

BACKGROUND

The aim of this study was to report a Western experience in the diagnosis and management of choledochal cyst disease.

RESULTS

Sixty-seven patients were identified including 15 children and 52 adults; 76.1 % were females. The median age at diagnosis was 3 [inter-quartile range (IQR) = 6.0-0.7] years for children, and 46 [IQR = 55.6-34.3] years for adults. Forty-eight patients (72 %) were symptomatic. Types of choledochal cyst included: I (n = 49, 73.1 %), II (n = 1, 1.5 %), IV (n = 9, 13.4 %), and V (n = 8, 12 %). The median diameter of the type I choledochal cyst was 35 [IQR = 47-25] mm. All 48 patients underwent excision of cyst with Roux-en-Y hepaticojejunostomy, and eight underwent resection with hepaticoduodenostomy. Six patients underwent liver resection, and five patients underwent orthotopic liver transplantation. Malignancy was concomitant in five adult patients, being identified on preoperative imaging in three cases; and atypia was seen in three additional patients. Early morbidity included Clavien-Dindo classification grades III (n = 7) and II (n = 5), while long-term complications consisted of Clavien-Dindo grades V (n = 5), IV (n = 2), III (n = 18), and II (n = 1).

CONCLUSIONS

Presentation and management of choledochal cyst is varied. Malignant transformation is often detected incidentally, and so should be the driving source for resection when a choledochal cyst is diagnosed.

Surgical Management of Caroli's Disease: Single Center Experience and Review of the Literature

BACKGROUND

Caroli's disease is a rare congenital condition characterized by non-obstructive dilatation of intrahepatic ducts. In Caroli's syndrome, there is additionally an associated congenital hepatic fibrosis.

METHODS

With institutional review board approval, we identified all patients with Caroli's disease and syndrome.

RESULTS

Nine patients were identified, seven males and two females, with a median age of 40 years. Final pathological diagnoses included Caroli's disease (n = 6) and Caroli's syndrome (n = 3). Patients presented with deranged liver function, cholangitis, cholangiocarcinoma, abdominal pain, cirrhosis, or were diagnosed incidentally. Four patients underwent resection and two underwent liver transplantation. Of the resection group, two patients subsequently underwent transplantation for recurrent cholangitis due to anastomotic stricture in one patient and for end-stage liver disease in the other. All patients with Caroli's syndrome underwent liver transplantation. Three patients died during follow-up at 26.2, 7.8, and 3 months post-diagnosis with recurrence of cholangiocarcinoma, liver failure, and metastatic cholangiocarcinoma, respectively. Six patients are alive with a median follow-up of 60 months since presentation (range = 10-134 months).

CONCLUSIONS

Caroli's disease and syndrome have a varied presentation. Most individuals with Caroli's disease may be adequately treated by resection, but transplantation is required for Caroli's syndrome patients due to the associated hepatic fibrosis.

Proposal for an algorithm for liver transplantation in Caroli's disease and syndrome: putting an uncommon effort into a common task

Liver transplantation (LT) represents an uncommon indication for Caroli's disease (CD) or syndrome (CS). Excellent results of LT have been reported as shown by recent multicentric European and American registry reports. Clear therapeutic flowcharts to adopt in these diseases are still lacking. This review aims at analyzing highlighting recent transplant experiences in this field and also at focusing on the role of LT in case-specific comorbidities such as development of cholangiocellular cancer or renal failure are present.

Nephronophthisis 13: implications of its association with Caroli disease and altered intracellular localization of WDR19 in the kidney

BACKGROUND

Nephronophthisis 13 (NPHP 13) is associated with mutations in the WDR19 gene, which encodes for a protein in the intraflagellar transport complex. Herein, we describe six additional cases accompanied by Caroli syndrome or disease.

METHODS

Targeted exome sequencing covering 96 ciliopathy-related genes was performed for 48 unrelated Korean patients with a clinical suspicion of NPHP. Mutations were confirmed by Sanger sequencing. We evaluated the expression of WDR19 in the biopsied kidney by immunohistochemistry in patients and controls.

RESULTS

We detected three (3/48, 6.3 %) unrelated index cases with WDR19 mutations. One of the cases involved two siblings with the same mutation. Later, we detected an additional index case with a similar phenotype of kidney and liver involvement by Sanger sequencing of WDR19. The p.R1178Q mutation was common in all patients. All of the six affected patients from four families progressed to chronic kidney disease. Of note, all six patients had Caroli syndrome or disease. Immunohistochemistry for WDR19 showed localized expression along the luminal borders of the renal tubular epithelium in controls, whereas it showed diffuse cytoplasmic staining in the affected patients.

CONCLUSIONS

Caroli disease is a major extra-renal phenotype associated with mutations in WDR19 in the Korean population. In this study, we visually validated the expression pattern of mutant WDR19 protein in the kidneys of NPHP 13 patients. More data are needed to identify the true frequency of p.R1178Q. Functional studies including transfection assay will provide solid grounds for the pathogenicity of each mutation.

Caroli's disease misdiagnosed as intraductal papillary neoplasm of the bile duct

Caroli's disease is a rare autosomal-recessive disorder caused by malformation of the ductal plate during embryonic development. Although it is present at birth, Caroli's disease is typically not diagnosed until between the second and fourth decades of life, as it was in the present patient. Here we report a rare case of Caroli's disease limited to one liver segment, which was initially misdiagnosed as an intraductal papillary neoplasm of the bile duct. The asymptomatic patient was treated with liver segmentectomy.

Clinical presentation, risk factors and staging systems of cholangiocarcinoma

Cholangiocarcinoma (CCA) is the second most common primary liver tumour. Intra-hepatic CCA develops within the liver parenchyma while extrahepatic CCA involves the biliary tree within the hepatoduodenal ligament. Hilar CCA are also called Klatskin tumour. The CCA incidence has increased worldwide over the last years, but there are also geographic differences, with focus in Asian countries. Known risk factors are primary sclerosing cholangitis (PSC), hepatolithiasis, Caroli's disease, hepatitis B and C infection, liver flukes, cirrhosis, diabetes, obesity, alcohol consumption and probably tobacco smoking. Patients with early CCA have only little discomfort, but can later show episodes with jaundice and other non-specific tumour symptoms. For the staging of the disease different classifications are available, which consider various factors like tumour size, location, regional lymph nodes, metastasis, vascular involvement and tumour marker.

Clinical classification of Caroli's disease: an analysis of 30 patients

BACKGROUND

Caroli's disease (CD) is a rare congenital disorder. The early diagnosis of the disease and differentiation of types I and II are of extreme importance to patient survival. This study was designed to review and discuss observations in 30 patients with CD and to clarify the clinical characteristics of the disease.

METHODS

The demographic and clinical features, laboratory indicators, imaging findings and pathology results for 30 patients with CD were reviewed retrospectively.

RESULTS

Caroli's disease can occur at any age. The average age of onset in the study cohort was 24 years. Patients who presented with symptoms before the age of 40 years were more likely to develop type II CD. Approximately one-third of patients presented without positive signs at original diagnosis and most of these patients were found to have type I CD on pathology. Anaemia, leucopoenia and thrombocytopoenia were more frequent in patients with type II than type I CD. Magnetic resonance cholangiopancreatography (MRCP) and computed tomography (CT) examinations were most useful in diagnosing CD.

CONCLUSIONS

No typical symptoms, signs or laboratory indicators are able to distinguish CD from other conditions. Both MRCP and CT were most valuable in diagnosis. The two types of CD may be differentiated by age of onset and routine blood tests.

Caroli disease associated with vein of Galen malformation in a male child

We report the first case of a male child with both Caroli disease and vein of Galen malformation. The neonate presented to our department with congestive heart failure as a result of the intracranial arteriovenous high-flow shunt. Over time, several endovascular embolizations led to a complete angiographic occlusion of the shunt. Additionally, the diagnosis of Caroli disease was made at the age of 2 months. He developed choledocholithiasis necessitating endoscopic sphincterotomy and stone extraction. As a prolonged medical treatment he received ursodeoxycholic acid and antibiotics. A coincidence of Caroli disease and vein of Galen malformation has not yet been described. Both diseases are very rare, leading to the question of whether there is a link in the pathogenesis. Based on the few previously described underlying mechanisms, we develop hypotheses about the relationship between both rare diseases. We consider overexpression of vascular endothelial growth factor and its receptors as a possible common molecular mechanism in their pathogenesis. We also highlight the critical role of increased expression of the Notch ligand Jagged 1 both in the development of cerebral arteriovenous malformations in general and in the formation of dilated intrahepatic bile ducts (eg, in Caroli disease).

Whole exome sequencing identifies recessive PKHD1 mutations in a Chinese twin family with Caroli disease

BACKGROUND

Mutations in PKHD1 cause autosomal recessive Caroli disease, which is a rare congenital disorder involving cystic dilatation of the intrahepatic bile ducts. However, the mutational spectrum of PKHD1 and the phenotype-genotype correlations have not yet been fully established.

METHODS

Whole exome sequencing (WES) was performed on one twin sample with Caroli disease from a Chinese family from Shandong province. Routine Sanger sequencing was used to validate the WES and to carry out segregation studies. We also described the PKHD1 mutation associated with the genotype-phenotype of this twin.

RESULTS

A combination of WES and Sanger sequencing revealed the genetic defect to be a novel compound heterozygous genotype in PKHD1, including the missense mutation c.2507 T>C, predicted to cause a valine to alanine substitution at codon 836 (c.2507T>C, p.Val836Ala), and the nonsense mutation c.2341C>T, which is predicted to result in an arginine to stop codon at codon 781 (c.2341C>T, p.Arg781*). This compound heterozygous genotype co-segregates with the Caroli disease-affected pedigree members, but is absent in 200 normal chromosomes.

CONCLUSIONS

Our findings indicate exome sequencing can be useful in the diagnosis of Caroli disease patients and associate a compound heterozygous genotype in PKHD1 with Caroli disease, which further increases our understanding of the mutation spectrum of PKHD1 in association with Caroli disease.

Surgical management of congenital intrahepatic bile duct dilatation, Caroli's disease and syndrome: long-term results of the French Association of Surgery Multicenter Study

OBJECTIVE

To assess clinical presentation and long-term results of surgical management of congenital intrahepatic bile duct dilatation (IHBDD) (Caroli disease and syndrome) in a multicenter setting.

BACKGROUND

Congenital IHBDD predisposes to biliary stasis, resulting in intrahepatic lithiasis, septic complications, and cholangiocarcinoma. Although liver resection (LR) is considered to be the treatment of choice for unilobar disease extent into the liver, the management of bilobar disease and/or associated congenital hepatic fibrosis remains challenging.

METHODS

From 1978 to 2011, a total of 155 patients (median age: 55.7 years) were enrolled from 26 centers. Bilobar disease, Caroli syndrome, liver atrophy, and intrahepatic stones were encountered in 31.0%, 19.4%, 27.7%, and 48.4% of patients, respectively. A complete resection of congenital intrahepatic bile ducts was achieved in 90.5% of the 148 patients who underwent surgery.

RESULTS

Postoperative mortality was nil after anatomical LR (n = 111) and 10.7% after liver transplantation (LT) (n = 28). Grade 3 or higher postoperative morbidity occurred in 15.3% of patients after LR and 39.3% after LT. After a median follow-up of 35 months, the 5-year overall survival rate was 88.5% (88.7% after LT), and the Mayo Clinic score was considered as excellent or good in 86.0% of patients. The 1-year survival rate was 33.3% for the 8 patients (5.2%) who presented with coexistent cholangiocarcinoma.

CONCLUSIONS

LR for unilobar and LT for diffuse bilobar congenital IHBDD complicated with cholangitis and/or portal hypertension achieved excellent long-term patient outcomes and survival. Because of the bad prognosis of cholangiocarcinoma and the sizeable morbidity-mortality after LT, timely indication for surgical treatment is of major importance.

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.

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.

Bile duct cyst in adults: Interventional treatment, resection, or transplantation?

Cystic dilatations of the bile ducts may be found along the extrahepatic biliary tree, within the liver, or in both of these locations simultaneously. Presentation in adults is often associated with complications. The therapeutic possibilities have changed considerably over the last few decades. If possible, complete resection of the cyst(s) can cure the symptoms and avoid the risk of malignancy. According to the type of bile duct cyst, surgical procedures include the Roux-en-Y hepaticojejunostomy and variable types of hepatic resection. However, the diffuse forms of Todani type V cysts (Caroli disease and Caroli syndrome) in particular remain a therapeutic problem, and liver transplantation has become an important option. The mainstay of interventional treatment for Todani type III bile duct cysts is via endoscopic retrograde cholangiopancreatography. The diagnostic term “bile duct cyst” comprises quite different pathological and clinical entities. Interventional therapy, hepatic resection, and liver transplantation all have their place in the treatment of this heterogeneous disease group. They should not be seen as competitive treatment modalities, but as complementary options. Each patient should receive individualized treatment after all of the clinical findings have been considered by an interdisciplinary team.

Caroli disease, bilateral diffuse cystic renal dysplasia, situs inversus, postaxial polydactyly, and preauricular fistulas: a ciliopathy caused by a homozygous NPHP3 mutation

We report the rare association of Caroli disease (intrahepatic bile duct ectasia associated with congenital hepatic fibrosis), bilateral cystic renal dysplasia, situs inversus, postaxial polydactyly, and preauricular fistulas in a female child. She presented with end-stage renal disease at the age of 1 month, followed by a rapidly progressing hepatic fibrosis and dilatation of the intrahepatic bile ducts, leading to secondary biliary cirrhosis and portal hypertension. Combined liver-kidney transplantation was performed at the age of 4 years, with excellent outcome. DNA analysis showed a NPHP3 (coding nephrocystin-3) homozygote mutation, confirming that this malformation complex is a ciliopathy.

CONCLUSION

This rare association required an exceptional therapeutic approach: combined simultaneous orthotopic liver and kidney transplantation in a situs inversus recipient. The long-term follow-up was excellent with a very good evolution of the renal and hepatic grafts and normalization of growth and weight. This malformation complex has an autosomal recessive inheritance with a 25% recurrence risk in each pregnancy.

Unilobar Caroli's disease and its management in an 8-year-old girl

A case of unilobar Caroli's disease in an 8-year-old girl treated with left hepatectomy is reported here.

Liver transplant for cholestatic liver diseases

Cholestatic liver diseases include a group of diverse disorders with different epidemiology, pathophysiology, clinical course, and prognosis. Despite significant advances in the clinical care of patients with cholestatic liver diseases, liver transplant (LT) remains the only definitive therapy for end-stage liver disease, regardless of the underlying cause. As per the United Network for Organ Sharing database, the rate of cadaveric LT for cholestatic liver disease was 18% in 1991, 10% in 2000, and 7.8% in 2008. This review summarizes the available evidence on various common and rare cholestatic liver diseases, disease-specific issues, and pertinent aspects of LT.

Surgical management of cystic lesions in the liver

BACKGROUND

Liver cysts are common, occurring in up to 5% of the population. For many types of cysts, a variety of different treatment options exist and the preferred management is unclear.

METHODS

A PubMed and Medline literature review was undertaken and articles pertaining to the diagnosis and management of cystic lesions within the liver were retrieved.

RESULTS

Therapy for symptomatic cysts may incorporate aspiration with sclerotherapy or de-roofing. Polycystic liver disease presents a unique management problem because of the high morbidity and mortality rates from intervention and high rates of recurrence. Careful patient counselling and assessment of symptom index is essential before embarking on any treatment. New medical treatments may ameliorate symptoms. Acquired cystic lesions in the liver require a thorough work-up to fully characterize the abnormality and direct appropriate treatment. Hydatid cysts are best treated by chemotherapy, followed by some form of surgical intervention (either aspiration and sclerotherapy or surgery). Liver abscesses can be effectively treated by aspiration or drainage.

CONCLUSION

All patients with cystic lesions in the liver require discussion at multidisciplinary meetings to confirm the diagnosis and determine the most appropriate method of treatment.

Anatomic hepatectomy as a definitive treatment for hepatolithiasis: a cohort study

BACKGROUND

Treatment requirements in hepatolithiasis may vary and may involve a multidisciplinary approach. Surgical resection has been proposed as a definitive treatment.

OBJECTIVES

This study aimed to evaluate the clinical results of anatomic liver resection among Chilean patients with hepatolithiasis.

METHODS

An historical cohort study was conducted. Patients who underwent hepatectomy as a definitive treatment for hepatolithiasis from January 1990 to December 2010 were included. Patients with a preoperative diagnosis of cholangiocarcinoma were excluded. Preoperative, operative and postoperative variables were evaluated.

RESULTS

A total of 52 patients underwent hepatectomy for hepatolithiasis. The mean ± standard deviation patient age was 49.8 ± 11.8 years (range: 24-78 years); 65.4% of study subjects were female. A total of 75.0% of subjects had a history of previous cholecystectomy. The main presenting symptom was abdominal pain (82.7%). Hepatic involvement was noted in the left lobe in 57.7%, the right lobe in 34.6% and bilaterally in 7.7% of subjects. The rate of postoperative clearance of the biliary tree was 90.4%. Postoperative morbidity was 30.8% and there were no postoperative deaths. Three patients had recurrence of hepatolithiasis, which was associated with Caroli's disease in two of them. Overall 5-year survival was 94.5%.

CONCLUSIONS

Anatomic liver resection is an effective treatment in selected patients with hepatolithiasis and is associated with low morbidity and no mortality. At longterm follow-up, anatomic hepatectomy in these patients was associated with a lower rate of recurrence.

Focal intrahepatic strictures: a review of diagnosis and management

INTRODUCTION

Focal intrahepatic strictures are becoming more common owing to more prevalent and accurate cross-sectional imaging. However, data relating to their management are lacking. The purpose of the present review was to synthesize the current evidence regarding these lesions and to formulate a strategy for diagnosis and management.

METHODS

A literature search of relevant terms was performed using Medline. References of papers were subsequently searched to obtain older literature.

RESULTS

Focal intrahepatic strictures involve segmental hepatic ducts and/or left and right main hepatic ducts during their intrahepatic course. Most patients are asymptomatic while the minority present with vague abdominal pain or recurrent sepsis and only rarely with jaundice. Investigations used to distinguish benign from malignant aetiologies include blood tests (CEA, Ca19.9), imaging studies [ultrasonography (US), computed tomography (CT), magnetic resonance cholangiopancreatography (MRCP) and fluorodeoxyglucose-positron emission tomography (FDG-PET)], endoscopic modalities [endoscopic retrograde cholangiopancreatography (ERCP)/endoscopic ultrasound (EUS)/cholangioscopy] and tissue sampling (brush cytology/biopsy).

CONCLUSIONS

A focal intrahepatic stricture requires thorough investigation to exclude malignancy even in patients with a history of biliary surgery, hepatolithiasis or parasitic infection. If during the investigative process a diagnosis or suspicion of malignancy is demonstrated then surgical resection should be performed. If all diagnostic modalities suggest a benign aetiology, then cholangioscopy with targeted biopsies should be performed.

Congenital hepatic fibrosis and autosomal recessive polycystic kidney disease

OBJECTIVES

The published natural history of congenital hepatic fibrosis (CHF) was examined to inform clinical decision making in autosomal recessive polycystic kidney disease (ARPKD).

METHODS

A systematic literature search of the data on CHF, ARPKD, Caroli disease, Caroli syndrome, and type V choledochal cyst was performed to extract data related to portal hypertension, infection, malignancy, mortality, and transplantation.

RESULTS

Information related to 1230 patients with CHF was extracted from 155 articles. Median and mean age at diagnosis were 2 and 11.2 years, respectively. Median and mean time followed after diagnosis were 5.0 and 7.5 years, respectively (range 0-38 years). Sequelae of portal hypertension (n = 409), cholangitis (n = 152), and malignancy (n = 21) were noted. The nature of the portal hypertension was similar to that in other pediatric conditions (164 with varices, 74 bleeding varices, 81 underwent portosystemic shunting). Documented cholangitis was fatal in 3 of 23 children who were infected after renal transplantation. Twenty-one patients developed hepatobiliary cancer, with the majority having cholangiocarcinoma (n = 19). Cholangiocarcinoma (CCA) was predominant in individuals older than 40 years with either Caroli syndrome or isolated CHF, not ARPKD (median and mean age at CCA diagnosis were 70.3 and 60.1 years, respectively; range 33-75 years). There was a relative paucity of data on combined liver-kidney transplantation.

CONCLUSIONS

Clinical decision making in ARPKD should reflect an understanding of the potential issues emanating from CHF. Accepted pediatric specific approaches to portal hypertension are warranted but must take into consideration the stage of renal insufficiency and potential plans for renal transplantation. Cholangitis is a major issue and necessitates anticipatory guidance and awareness. CCA, although a dreaded complication, does not appear to be a major issue during childhood. The indications for liver and combined liver-kidney transplantation are controversial and warrant further analysis.

Caroli disease patients have excellent survival after liver transplant

BACKGROUND

Caroli disease (CD) is characterized by dilation of the intrahepatic biliary tree, which may result in malignancy. Treatments include management of symptoms and hepatic resection to decrease disease burden. In patients with CD not amenable to these treatments, orthotopic liver transplantation (OLT) has been used. This study examines if OLT is a reasonable treatment for patients with CD.

MATERIALS AND METHODS

The United Network of Organ Sharing/Organ Procurement and Transplantation Network database between September 30, 1987 and March 31, 2011 was queried. Cases without patient or allograft survival time or without a diagnosis were excluded from analysis. Patients with CD were compared to patients with primary biliary cirrhosis (PBC), secondary biliary cirrhosis (BC), primary sclerosing cholangitis (PSC), and all indications for OLT. Survival analysis was performed by log-rank test and Kaplan-Meier.

RESULTS

One hundred forty patients with CD were compared to 4797 patients with PBC, 489 patients with secondary BC, 6033 patients with PSC, and 92,210 patients post-OLT. Patient and allograft survivals of CD patients at 1, 3, 5, and 10 y are, respectively, 88.5%, 83.4%, 80.9%, and 77.8%; and 81.2%, 74.8%, 70.6%, and 67.9%. CD patients have significantly improved patient and allograft survivals after OLT compared to patients with secondary BC (P = 0.003, P = 0.015) and all other patients undergoing OLT (P = 0.003, P = 0.026). There is a trend towards long-term improved patient and allograft survival in transplanted patients with CD compared to patients with PBC and PSC.

CONCLUSIONS

These results suggest that OLT should be considered an effective treatment modality for patients with CD resulting in excellent long-term outcomes.

Surgical management of cystic lesions in the liver

BACKGROUND

Liver cysts are common, occurring in up to 5% of the population. For many types of cysts, a variety of different treatment options exist and the preferred management is unclear.

METHODS

A Pubmed and Medline literature review using key words non-parasitic hepatic cysts, polycystic liver disease, echinococcus, hydatid cysts parasitic cysts, Caroli's disease, cystadenoma; liver abscess, surgery, aspiration and treatment was undertaken and papers pertaining to the diagnosis and management of cystic lesions within the liver were retrieved.

RESULTS

Asymptomatic simple cysts in the liver require no treatment. Therapy for symptomatic cysts may incorporate aspiration with sclerotherapy or de-roofing. At present, insufficient evidence exists to recommend one over the other. Polycystic liver disease presents a unique management problem because of high morbidity and mortality rates from intervention and high rates of recurrence. Careful patient counselling and assessment of symptom index is essential before embarking on any treatment. New medical treatments may ameliorate symptoms. Acquired cystic lesions in the liver require a thorough work-up to fully characterize the abnormality and direct appropriate treatment. Hydatid cysts are best treated by chemotherapy followed by some form of surgical intervention (either aspiration and sclerotherapy or surgery). Liver abscesses can effectively be treated by aspiration or drainage. With improved antimicrobial efficacy, prolonged treatment with antibiotics may also be considered.

CONCLUSION

All patients with cystic lesions in the liver require discussion at multi-disciplinary meetings to confirm and the diagnosis and determine the most appropriate method of treatment.

Pediatric liver transplantation for fibropolycystic liver disease

Fibropolycystic liver disease includes CHF, Caroli's syndrome, and Caroli's disease. Patients with Caroli's disease and Caroli's syndrome have an increased risk of recurrent cholangitis, intrahepatic calculi, biliary cirrhosis, and cholangiocarcinoma. The aim of this study was to examine the post-transplantation outcomes of children with fibropolycystic liver disease. Of the 158 children transplanted at Seoul National University Hospital, there were four patients with Caroli's syndrome, two patients with CHF, and one patient with Caroli's disease. One patient underwent combined liver/kidney transplantation. Associated renal manifestations included ARPKD in three children and nephronophthisis in one child. The indications for LT were recurrent cholangitis, decompensated cirrhosis, and refractory complications of portal hypertension. Both graft and patient survival rates were 100% at a median follow-up period of two yr after LT. Three children with growth failure achieved catch-up growth after LT. In three patients with ARPKD, mean serum creatinine levels increased from 0.53 mg/dL at the time of LT to 0.91 mg/dL at the last follow-up (p = 0.01). LT is an excellent option for children with complications from fibropolycystic liver disease. Renal function should be monitored cautiously after LT in the patients with ARPKD.

Caroli's Disease: Current Knowledge of Its Biliary Pathogenesis Obtained from an Orthologous Rat Model

Caroli's disease belongs to a group of hepatic fibropolycystic diseases and is a hepatic manifestation of autosomal recessive polycystic kidney disease (ARPKD). It is a congenital disorder characterized by segmental saccular dilatations of the large intrahepatic bile duct and is frequently associated with congenital hepatic fibrosis (CHF). The most viable theory explaining its pathogenesis suggests that it is related to ductal plate malformation. The development of the polycystic kidney (PCK) rat, an orthologous rodent model of Caroli's disease with CHF as well as ARPKD, has allowed the molecular pathogenesis of the disease and the therapeutic options for its treatment to be examined. The relevance of the findings of studies using PCK rats and/or the cholangiocyte cell line derived from them to the pathogenesis of human Caroli's disease is currently being analyzed. Fibrocystin/polyductin, the gene product responsible for ARPKD, is normally localized to primary cilia, and defects in the fibrocystin from primary cilia are observed in PCK cholangiocytes. Ciliopathies involving PCK cholangiocytes (cholangiociliopathies) appear to be associated with decreased intracellular calcium levels and increased cAMP concentrations, causing cholangiocyte hyperproliferation, abnormal cell matrix interactions, and altered fluid secretion, which ultimately result in bile duct dilatation. This article reviews the current knowledge about the pathogenesis of Caroli's disease with CHF, particularly focusing on studies of the mechanism responsible for the biliary dysgenesis observed in PCK rats.