European Association for the Study of the Liver (EASL). Electronic address: easloffice@easloffice.eu. EASL Clinical Practice Guidelines on the prevention, diagnosis and treatment of gallstones

Liver Fibrosis Is Associated With Corrected QT Prolongation During Ledipasvir/Sofosbuvir Treatment for Patients With Chronic Hepatitis C

Combination treatment of ledipasvir and sofosbuvir (LDV/SOF) is first-line treatment for patients with chronic hepatitis C genotype 1 in the United States, Europe, and Japan. However, the influence of LDV/SOF on the cardiovascular system is poorly characterized. A total of 470 chronic hepatitis C patients who started LDV/SOF treatment between September 2015 and February 2016 at nine hospitals in Japan were prospectively enrolled in this study. Corrected QT (QTc) prolongation was defined as a QTc interval ≥450 milliseconds. The sustained virologic response rate was 96.0% (451/470), and the discontinuance rate due to adverse effects was 0.9% (4/470). Among 395 patients whose electrocardiogram was evaluated over time and compared with baseline, the QTc interval was significantly prolonged during treatment and returned to baseline levels 12 weeks after the end of treatment. Twenty-four of 376 patients with baseline QTc intervals <450 milliseconds experienced on-treatment QTc prolongation. Higher aspartate aminotransferase-to-platelet ratio index scores (≥0.76; odds ratio, 4.375; P = 0.005) and longer QTc intervals (≥416 milliseconds; odds ratio, 4.823; P = 0.003) at baseline were significantly associated with on-treatment QTc prolongation on multivariate analysis. Patients with cirrhosis showed significantly longer QTc intervals than those without cirrhosis during treatment but not at baseline, and they developed on-treatment QTc prolongation at a higher rate than patients without cirrhosis. No cardiovascular events occurred, except for 1 patient who developed paroxysmal supraventricular tachycardia. Conclusion: Newly developed QTc prolongation was observed in 6.4% of Japanese patients during treatment and was associated with more advanced fibrosis. (Hepatology Communications 2018; 00:000-000).

Pancreatitis

Acute pancreatitis is an inflammation of the glandular parenchyma of the retroperitoneal organ that leads to injury with or without subsequent destruction of the pancreatic acini. This inflammatory process can either result in a self-limited disease or involve life-threatening multiorgan complications. Chronic pancreatitis consists of endocrine and exocrine gland dysfunction that develops secondary to progressive inflammation and chronic fibrosis of the pancreatic acini with permanent structural damage. Recurrent attacks of acute pancreatitis can result in chronic pancreatitis; acute and chronic pancreatitis are different diseases with separate morphologic patterns. Acute pancreatitis has an increasing incidence but a decreasing mortality.

Current clinical algorithms for predicting common bile duct stones have only moderate accuracy

BACKGROUND AND AIM

A risk-stratified approach for selecting patients likely to harbor common bile duct (CBD) stones to proceed directly to endoscopic or surgical stone clearance, rather than undergo less invasive testing, has been proposed. We assessed the performance of three clinical algorithms used to predict CBD stones.

METHODS

All patients undergoing first-time endoscopic retrograde cholangiopancreatography (ERCP) in 2011-2012 as a result of suspected CBD stones were enrolled prospectively in a clinical database. Data such as imaging test findings and liver function tests (LFTs) were collected 48 h prior to and on the day of ERCP. Patients were stratified into different risk groups for harboring CBD stones according to three clinical algorithms using imaging and laboratory data. Findings on ERCP were used as gold standard. Performance characteristics of each algorithm were separately calculated for each time point of LFT assessment.

RESULTS

Overall, 186 patients were analyzed, 75% of whom presented CBD stones on ERCP. Proportion of patients categorized as high-risk for harboring CBD stones varied among the three algorithms (67% vs 73% vs 56%). Also, the algorithms showed only moderate, albeit comparable, accuracy for predicting the presence of CBD stones (0.65, 95% confidence interval [CI] 0.62-0.68 vs 0.68, 95% CI 0.63-0.67 vs 0.59, 95% CI 0.57-0.61). Similar results were obtained when performance characteristics were recalculated using LFT from 48 h prior to ERCP (data not shown).

CONCLUSION

Three diagnostic algorithms commonly used for predicting CBD stones have comparable but only moderate accuracy. Further research is warranted to improve risk stratification of patients with suspected CBD stones.

Cholelithiasis and choledocholithiasis in children; risk factors for development

PURPOSE

To compare anthropometric data (body mass index [BMI]) in patients without lithiasis to patients with symptomatic simple cholelithiasis or choledocholithiasis.

METHODS

We retrospectively reviewed data from 147 patients undergoing laparoscopic cholecystectomy between 2001-2015. Complete growth data from 98 patients was compared with anthropometric data from the population of the Czech Republic and a control group (BMI of 100 consecutive patients without biliary stones in abdominal ultrasound who were admitted to a surgical department for suspected appendicitis).

RESULTS

The BMI of 75 children with simple cholelithiasis and 23 with choledocholithiasis was compared to the standard Czech pediatric population and to the control group. The median age (simple cholelithiasis and choledocholithiasis) was 16 years, and 35 patients (24%) had a family history of gallstones. Types of lithiasis included multiple (n = 120), solitary (n = 11), and sludge (n = 10). Five cases had polyps and one had gallbladder dysplasia. Patients with simple cholelithiasis had significantly higher BMI compared to the control group without cholelithiasis (p<0.0001) and the standard Czech population (p = 0.03). Patients with choledocholithiasis had a mean BMI significantly higher than that of the general population (p = 0.001) and the control group (p = 0.0001). Patients with choledocholithiasis had significantly higher BMI than those with simple cholelithiasis (p = 0.03).

CONCLUSION

Patients with cholelithiasis had significantly higher BMI than the general population, and patients with choledocholithiasis had significantly higher BMI than patients with simple lithiasis. Elevated BMI is a risk factor for developing choledocholithiasis. ERCP and early laparoscopic cholecystectomy in patients with choledocholithiasis offer equivalent outcomes in patients with simple cholelithiasis.

Recurrent biliary acute pancreatitis is frequent in a real-world setting

BACKGROUND

Data about recurrent acute pancreatitis (RAP) are limited.

AIMS

To evaluate the rate of RAP and associated factors.

METHODS

Single-centre prospective study of consecutive patients at first episode of acute pancreatitis (AP) being followed-up.

RESULTS

Of 266 consecutive AP patients, (47% biliary, 15.4% alcoholic, 14.3% idiopathic) 66 (24.8%) had RAP in a mean follow-up of 42 months; 17.9% of recurrences occurred within 30 days from discharge. Age, gender, smoking and severity of first AP were not associated with RAP risk. The rate of biliary RAP was 31.3% in patients who did not receive any treatment, 18% in those treated with ERCP only, 16% in those who received cholecystectomy only, and 0% in those treated both with surgery and ERCP. Patients with biliary AP who received cholecystectomy had a significantly longer time of recurrence-free survival and reduced recurrence risk (HR = 0.45). In patients with alcoholic AP, the rate of recurrence was lower in those who quit drinking (5.8% vs 33%; p = 0.05). The alcoholic aetiology was associated with a higher risk of having >2 RAP episodes.

CONCLUSION

RAP occurs in about 25% of cases, and failure to treat biliary aetiology or quitting drinking is associated with increased recurrence risk.

An update on the pathogenesis of cholesterol gallstone disease

PURPOSE OF REVIEW

Gallstone disease is a major epidemiologic and economic burden worldwide, and the most frequent form is cholesterol gallstone disease.

RECENT FINDINGS

Major pathogenetic factors for cholesterol gallstones include a genetic background, hepatic hypersecretion of cholesterol, and supersaturated bile which give life to precipitating cholesterol crystals that accumulate and grow in a sluggish gallbladder. Additional factors include mucin and inflammatory changes in the gallbladder, slow intestinal motility, increased intestinal absorption of cholesterol, and altered gut microbiota. Mechanisms of disease are linked with insulin resistance, obesity, the metabolic syndrome, and type 2 diabetes. The role of nuclear receptors, signaling pathways, gut microbiota, and epigenome are being actively investigated.

SUMMARY

Ongoing research on cholesterol gallstone disease is intensively investigating several pathogenic mechanisms, associated metabolic disorders, new therapeutic approaches, and novel strategies for primary prevention, including lifestyles.

Nonalcoholic fatty liver disease, cholesterol gallstones, and cholecystectomy: new insights on a complex relationship

PURPOSE OF REVIEW

Gallstone disease (GSD) and nonalcoholic fatty liver disease (NAFLD often coexist in a given patient and both conditions are associated to obesity and insulin resistance. The relationship between GSD and NAFLD is complex and bidirectional. In the present review, we summarize the existing information on the complex link between GSD and NAFLD and the potential implications for patient care.

RECENT FINDINGS

Several clinical studies and systematic reviews have addressed the association between NAFLD and GSD underscoring that NAFLD is an independent risk factor for GSD. Conversely, GSD has been found also to be an independent risk factor for NAFLD with GSD potentially being linked to greater disease severity. In addition to the data showing association of NAFLD and GSD, recent evidence has also showed that cholecystectomy may itself be a risk factor for NAFLD development. The complex and bidirectional relationship between these diseases is partially explained by a number of common pathogenic links but the precise underlying mechanisms of the association of GSD and NAFLD need to be better delineated. Also, although the mechanisms of the promotional effect of cholecystectomy on NAFLD development are unknown, recent findings unveiling new aspects of gallbladder physiology and endocrine actions of bile acids provide a framework to advance research in this field.

SUMMARY

In this review, we address the different aspects of the complex association between NAFLD and GSD. The potential underlying mechanisms and recent information on endocrine actions of bile acids and the gallbladder are reviewed.

Papillary balloon dilatation combined with endoscopic sphincterotomy for treatment of common bile duct stones: Efficacy and factors affecting stone recurrence

AIM

To evaluate the efficacy of endoscopic papillary balloon dilatation (EPBD) combined with endoscopic sphincterotomy (EST) in the treatment of common bile duct stones and to identify the factors affecting the recurrence of stones.

METHODS

One hundred patients with choledocholithiasis who underwent endoscopic retrograde cholangiopancreatography (ERCP) at our hospital between January 2014 and January 2016 were randomly divided into a control group and an experimental group. The patients in the control group and experimental group were given EST lithotomy and small-incision endoscopic sphincterotomy (SEST) combined with EPBD, respectively. The one-time success rate, total success rate, and the incidence of complications after ERCP were comparatively analyzed. The Kaplan-Meier survival curve of patients with postoperative stone recurrence was plotted, and the Cox regression model was used to explore the risk factors for postoperative recurrence in patients.

RESULTS

The maximum diameter of the stones (t = -1.055, P = 0.294), the rate of multiple stones (χ² = 0.644, P = 0.422), the maximum diameter of bile duct (t = -0.820, P = 0.414), and the stone removal success rate (94.0% and 100.0%, χ² = 1.375, P = 0.241) differed significantly between the control group and the experimental group. There was no significant difference in the one-time success rate between the control group and the experimental group (84.0% and 96.0%, χ² = 4.332, P = 0.037). The incidence of complications after ERCP in the control group and experimental group was 17.02% and 6.0%, respectively (χ² = 4.337, P = 0.036). A total of 97 patients were followed, with stone recurrence occurring in 11 cases. In the 97 patients followed, the incidence of complications after ERCP in the control group and experimental group was 17.02% and 6.0%, respectively (χ² = 2.927, P = 0.087). Log-rank test showed that the risk of gallstone recurrence in the experimental group was significantly lower than that in the control group (HR = 0.285, 95%CI: 0.095-0.888, P = 0.044). Multivariate Cox regression analysis showed that multiple endoscopic procedures, common bile duct angulation (≤ 145°), and EST were risk factors for ERCP recurrence.

CONCLUSION

The success rate and safety of EPBD combined with LEST in the management of common bile duct stones are high, and the risk of long-term stone recurrence is low. Multiple endoscopic operations and common bile duct angulation (≤ 145°) are risk factors for stone recurrence.

Tokyo Guidelines 2018: diagnostic criteria and severity grading of acute cholecystitis (with videos)

The Tokyo Guidelines 2013 (TG13) for acute cholangitis and cholecystitis were globally disseminated and various clinical studies about the management of acute cholecystitis were reported by many researchers and clinicians from all over the world. The 1^st edition of the Tokyo Guidelines 2007 (TG07) was revised in 2013. According to that revision, the TG13 diagnostic criteria of acute cholecystitis provided better specificity and higher diagnostic accuracy. Thorough our literature search about diagnostic criteria for acute cholecystitis, new and strong evidence that had been released from 2013 to 2017 was not found with serious and important issues about using TG13 diagnostic criteria of acute cholecystitis. On the other hand, the TG13 severity grading for acute cholecystitis has been validated in numerous studies. As a result of these reviews, the TG13 severity grading for acute cholecystitis was significantly associated with parameters including 30-day overall mortality, length of hospital stay, conversion rates to open surgery, and medical costs. In terms of severity assessment, breakthrough and intensive literature for revising severity grading was not reported. Consequently, TG13 diagnostic criteria and severity grading were judged from numerous validation studies as useful indicators in clinical practice and adopted as TG18/TG13 diagnostic criteria and severity grading of acute cholecystitis without any modification. Free full articles and mobile app of TG18 are available at: http://www.jshbps.jp/modules/en/index.php?content_id=47. Related clinical questions and references are also included.

Recent advances in understanding and managing cholesterol gallstones

The high prevalence of cholesterol gallstones, the availability of new information about pathogenesis, and the relevant health costs due to the management of cholelithiasis in both children and adults contribute to a growing interest in this disease. From an epidemiologic point of view, the risk of gallstones has been associated with higher risk of incident ischemic heart disease, total mortality, and disease-specific mortality (including cancer) independently from the presence of traditional risk factors such as body weight, lifestyle, diabetes, and dyslipidemia. This evidence points to the existence of complex pathogenic pathways linking the occurrence of gallstones to altered systemic homeostasis involving multiple organs and dynamics. In fact, the formation of gallstones is secondary to local factors strictly dependent on the gallbladder (that is, impaired smooth muscle function, wall inflammation, and intraluminal mucin accumulation) and bile (that is, supersaturation in cholesterol and precipitation of solid crystals) but also to "extra-gallbladder" features such as gene polymorphism, epigenetic factors, expression and activity of nuclear receptors, hormonal factors (in particular, insulin resistance), multi-level alterations in cholesterol metabolism, altered intestinal motility, and variations in gut microbiota. Of note, the majority of these factors are potentially manageable. Thus, cholelithiasis appears as the expression of systemic unbalances that, besides the classic therapeutic approaches to patients with clinical evidence of symptomatic disease or complications (surgery and, in a small subgroup of subjects, oral litholysis with bile acids), could be managed with tools oriented to primary prevention (changes in diet and lifestyle and pharmacologic prevention in subgroups at high risk), and there could be relevant implications in reducing both prevalence and health costs.

Cholecystectomy: a way forward and back to metabolic syndrome?

The gallbladder provides rhythmic secretion of concentrated bile acids (BAs) during fasting and postprandially contributes to digestion of dietary lipids. In addition, BAs activate metabolic pathways governing gluco-lipid homeostasis and energy expenditure via the farnesoid X nuclear receptor (FXR), G protein-coupled BA receptor 1 (GPBAR-1), and fibroblast growth factor 19 (FGF19) in the liver, intestine, brown fat, and muscle. Cholecystectomy is standard treatment worldwide for symptomatic gallstone patients. As excellently reviewed by Chen et al, cholecystectomy may disrupt enterohepatic recycling of, and signaling by, BAs. Further studies are needed to investigate whether gallbladder removal is an independent risk factor for development of the metabolic syndrome.

Surgery in biliary lithiasis: from the traditional "open" approach to laparoscopy and the "rendezvous" technique

BACKGROUND

According to the current literature, biliary lithiasis is a worldwide-diffused condition that affects almost 20% of the general population. The rate of common bile duct stones (CBDS) in patients with symptomatic cholelithiasis is estimated to be 10% to 33%, depending on patient's age. Compared to stones in the gallbladder, the natural history of secondary CBDS is still not completely understood. It is not clear whether an asymptomatic choledocholithiasis requires treatment or not. For many years, open cholecystectomy with choledochotomy and/or surgical sphincterotomy and cleaning of the bile duct were the gold standard to treat both pathologies. Development of both endoscopic retrograde cholangiopancreatography (ERCP) and laparoscopic surgery, together with improvements in diagnostic procedures, influenced new approaches to the management of CBDS in association with gallstones.

DATA SOURCES

We decided to systematically review the literature in order to identify all the current therapeutic options for CBDS. A systematic literature search was performed independently by two authors using PubMed, EMBASE, Scopus and the Cochrane Library Central.

RESULTS

The therapeutic approach nowadays varies greatly according to the availability of experience and expertise in each center, and includes open or laparoscopic common bile duct exploration, various combinations of laparoscopic cholecystectomy and ERCP and combined laparoendoscopic rendezvous.

CONCLUSIONS

Although ERCP followed by laparoscopic cholecystectomy is currently preferred in the majority of hospitals worldwide, the optimal treatment for concomitant gallstones and CBDS is still under debate, and greatly varies among different centers.

Alcohol, smoking and benign hepato-biliary disease

Gallstone disease and pancreatitis are the most frequent benign hepato-biliary causes of hospital admissions. Gallstone disease is prevalent, but symptomatic disease develops only in about one out of five carriers. Alcohol intake seems to protect gallstone formation in cohort studies possibly through effects on bile cholesterol metabolism, the enterohepatic circulation, and gallbladder function. The impact of smoking on gallstone formation seems minor. Both alcohol intake and smoking do not alter the clinical course of gallstone disease carriers. Cholecystectomy is the preferred treatment for symptomatic gallstone disease. Studies about the impact of alcohol and smoking on the post-cholecystectomy state are few and future studies should be performed. Pancreatitis is associated with both excessive alcohol intake and smoking in observational studies. Interpretation of associations with pancreatitis is hampered by an incomplete understanding of underlying mechanisms and by the co-existence of excessive alcohol intake and smoking. Smoking cessation and alcohol abstinence is recommended in the treatment of pancreatitis, but higher-level evidence is needed.

Risk assessment of choledocholithiasis prior to laparoscopic cholecystectomy and its management options

Background

Accurate risk evaluation of choledocholithiasis prior to laparoscopic cholecystectomy is essential to determine optimal management strategy.

Objective

Our study aimed to evaluate the accuracy of separate predictors and Vilnius University Hospital Index (VUHI = A/30 + 0.4 × B; A = total bilirubin concentration (µmol/l), B = common bile duct (CBD) diameter (mm) measured by ultrasound) diagnosing choledocholithiasis and to assess different management strategies (cholecystectomy with intraoperative cholangiography and endoscopic retrograde cholangiopancreatography (ERCP)).

Methods

The retrospective study included 350 patients admitted to a tertiary care centre for laparoscopic cholecystectomy for cholecystolithiasis who were investigated for concomitant choledocholithiasis.

Results

Choledocholithiasis was diagnosed in 182 (76.2%) cases in the high-risk group (VUHI value ≥4.7) and 44 (39.6%) in the low, odds ratio is 4.86 (95% CI: 3.00-7.88). Its sensitivity was 80.5%, specificity 54.0%, accuracy 71.1%. Dilated CBD had the highest sensitivity (92.5%) of predictors.ERCP showed better diagnostic performance than intraoperative cholangiography. Complications of ERCP were more frequent for patients without stones. There was no significant difference of outcomes between the two management strategies.

Conclusion

The prognostic index has good diagnostic accuracy but dividing patients into two risk groups is insufficient. The suggested model allows determining an intermediate-risk group, which requires additional investigation. Both management approaches are appropriate.

Genetic determinants of cholangiopathies: Molecular and systems genetics

Familial cholangiopathies are rare but potentially severe diseases. Their spectrum ranges from fairly benign conditions as, for example, benign recurrent intrahepatic cholestasis to low-phospholipid associated cholelithiasis and progressive familial intrahepatic cholestasis (PFIC). Many cholangiopathies such as primary biliary cholangitis (PBC) or primary sclerosing cholangitis (PSC) affect first the bile ducts ("ascending pathophysiology") but others, such as PFIC, start upstream in hepatocytes and cause progressive damage "descending" down the biliary tree and leading to end-stage liver disease. In recent years our understanding of cholestatic diseases has improved, since we have been able to pinpoint numerous disease-causing mutations that cause familial cholangiopathies. Accordingly, six PFIC subtypes (PFIC type 1-6) have now been defined. Given the availability of genotyping resources, these findings can be introduced in the diagnostic work-up of patients with peculiar cholestasis. In addition, functional studies have defined the pathophysiological consequences of some of the detected variants. Furthermore, ABCB4 variants do not only cause PFIC type 3 but confer an increased risk for chronic liver disease in general. In the near future these findings will serve to develop new therapeutic strategies for patients with liver diseases. Here we present the latest data on the genetic background of familial cholangiopathies and discuss their application in clinical practice for the differential diagnosis of cholestasis of unknown aetiology. As look in the future we present "system genetics" as a novel experimental tool for the study of cholangiopathies and disease-modifying genes. This article is part of a Special Issue entitled: Cholangiocytes in Health and Disease edited by Jesus Banales, Marco Marzioni, Nicholas LaRusso and Peter Jansen.

Effect of cholecystectomy on hepatic fat accumulation and insulin resistance in non-obese Hispanic patients: a pilot study

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is highly prevalent worldwide. Experimental studies have shown that cholecystectomy (XGB) increases hepatic fat content in mice and appears associated to NAFLD in large retrospective population-based studies. The aim of this study was to prospectively assess the effects of XGB on hepatic fat content (HFC) and insulin resistance (IR) in non-obese, middle aged Hispanic subjects.

METHODS

Twenty-six gallstone patients undergoing elective XGB and 16 control subjects with normal livers and gallbladders at ultrasonography were prospectively followed 24 months for changes in HFC and IR. Clinical, biochemical determinations and hepatic imaging were performed at baseline and 24 months after surgery. MRI technique quantified HFC in four hepatic segments. IR was assessed by the Homeostasis Model Assessment (HOMA_-IR) index.

RESULTS

Initial body mass index (BMI) was 25.6 ± 0.4 and 24.3 ± 1.0 in the control and XGB groups of subjects, respectively. Serum insulin level increased from 8.1 ± 0.7 to 10.0 ± 1.9 (μU/ml) 24 months after surgery in XGB patients (p < 0.05); no significant changes were detected in control individuals. Median HOMA_-IR index increased from 1.31 (interquartile range, 1.01-1.68) to 2.20 (interquartile range, 1.57 - 2.60) 24 months after XGB, (p < 0.003). Median HOMA_-IR index of control subjects remained unchanged at the end of the study. Serum apoB concentration increased from 61.5 ± 3.4 to 79.0 ± 7.8 (μg/ml) in XGB patients (p < 0.03). Serum apoB levels remained within normal ranges in both periods of the study in control subjects. HFC significantly increased in 2 of the 4 segments 24 months after XGB: right posterior hepatic lobe (from 5.3 ± 0.2% to 6.0 ± 0.2%, p > 0.04) and right anterior hepatic lobe (from 5.8 ± 0.2% to 6.6 ± 0.3%, p < 0.02). The average HFC of the four hepatic segments studied slightly increased from 5.4 ± 0.2 to 5.8 ± 0.3 2 years after XGB (p < 0.03). No significant changes were found in HFC in the control subjects at the end of the study.

CONCLUSIONS

Elective XGB increases HFC, HOMA_-IR index and serum apoB concentration. These results support the notion that XGB is a risk factor non-alcoholic fatty liver disease and other IR - associated disease conditions.

Assessment of available evidence in the management of gallbladder and bile duct stones: a systematic review of international guidelines

BACKGROUND

Gallstone disease is a frequent disorder in the Western world with a prevalence of 10-20%. Recommendations for the assessment and management of gallstones vary internationally. The aim of this systematic review was to assess quality of guideline recommendations for treatment of gallstones.

METHODS

PubMed, EMBASE and websites of relevant associations were systematically searched. Guidelines without a critical appraisal of literature were excluded. Quality of guidelines was determined using the AGREE II instrument. Recommendations without consensus or with low level of evidence were considered to define problem areas and clinical research gaps.

RESULTS

Fourteen guidelines were included. Overall quality of guidelines was low, with a mean score of 57/100 (standard deviation 19). Five of 14 guidelines were considered suitable for use in clinical practice without modifications. Ten recommendations from all included guidelines were based on low level of evidence and subject to controversy. These included major topics, such as definition of symptomatic gallstones, indications for cholecystectomy and intraoperative cholangiography.

CONCLUSION

Only five guidelines on gallstones are evidence-based and of a high quality, but even in these controversy exists on important topics. High quality evidence is needed in specific areas before an international guideline can be developed and endorsed worldwide.

Re-analysis of unassigned hepatitis C virus (HCV) strain CYHCV025: Evidence of a highly divergent lineage within genotype 1

HCV global sequences have been classified into 7 genotypes, several subtypes and a number of unassigned sequences. Our aim was to perform an in depth investigation of the taxonomic relationships of the unclassified CYHCV025 strain by means of phylogenetic analysis. Phylogenetic tree reconstructions were performed using ML methods on full-length genomic and partial HCV alignments. Phylogenetic analysis of full-length sequences revealed that CYHCV025 clustered close to the root node of genotype 1, showing distant genetic relationships to all previously classified subtypes and unclassified sequences. Single section analysis using the SSE showed that the distances between the query and all subtypes were much higher than distances within and between subtypes of genotype 1 (p<0.05). Recombination analysis revealed no evidence for intersubtype or genetic mixing between the query and the references from different genotype 1 subtypes. Different analyses revealed that CYHCV025 is the most genetically divergent within genotype 1, showing no high- or low-level clustering with any of the previous subtypes or unclassified sequences. Identification of a single lineage within a genotype without any late branching can be explained by "genetic isolation" until the late stage of HCV epidemic spread.

Choledocholithiasis: Evaluation, Treatment, and Outcomes

Choledocholithiasis occurs in up to approximately 20% of patients with cholelithiasis. A majority of stones form in the gallbladder and then pass into the common bile duct, where they generate symptoms, due to biliary obstruction. Confirmatory diagnosis of choledocholithiasis is made with advanced imaging, including magnetic resonance cholangiopancreatography and endoscopic retrograde cholangiopancreatography (ERCP). Treatment varies locally; however, ERCP with sphincterotomy is most commonly employed with a high degree of success. Difficult anatomy and difficult stone burden require advanced surgical, endoscopic, and percutaneous techniques to extract or expel biliary stones. Knowledge of these treatment strategies will optimize outcomes.