Advances and challenges in cirrhosis and portal hypertension

Incidence of portal vein thrombosis after splenectomy and its influence on transjugular intrahepatic portosystemic shunt stent patency

BACKGROUND

Transjugular intrahepatic portosystemic shunt (TIPS) is widely accepted as an alternative to surgery for management of complications of portal hypertension. TIPS has been used to treat portal vein thrombosis (PVT) in many centers since the 1990s. Although TIPS has good therapeutic effects on the formation of PVT, the effect of PVT on TIPS stenting has rarely been reported. Patients with splenectomy and pericardial devascu-larization have a high incidence of PVT, which can markedly affect TIPS stent patency and increase the risk of recurrent symptoms associated with shunt stenosis or occlusion.

AIM

To investigate the incidence of PVT after splenectomy and its influence on the patency rate of TIPS in patients with cirrhosis and portal hypertension.

METHODS

Four hundred and eighty-six patients with portal hypertension for refractory ascites and/or variceal bleeding who required TIPS placement between January 2010 and January 2016 were included in this retrospective analysis. Patients without prior splenectomy were defined as group A (n = 289) and those with prior splenectomy as group B (n = 197). The incidence of PVT before TIPS was compared between the two groups. After TIPS placement, primary patency rate was compared using Kaplan–Meier analysis at 3, 6, 9 and 12 mo, and 2 and 3 years. The clinical outcomes were analyzed.

RESULTS

Before TIPS procedure, the incidence of PVT in group A was lower than in group B (P = 0.003), and TIPS technical success rate in group A was higher than in group B (P = 0.016). The primary patency rate in group A tended to be higher than in group B at 3, 6, 9 and 12 mo, 2 years and 3 years (P = 0.006, P = 0.011, P = 0.023, P = 0.032, P = 0.037 and P = 0.028, respectively). Recurrence of bleeding and ascites rate in group A was lower than in group B at 3 mo (P ≤ 0.001 and P = 0.001), 6 mo (P = 0.003 and P = 0.005), 9 mo (P = 0.005 and P = 0.012), 12 mo (P = 0.008 and P = 0.024), 2 years (P = 0.011 and P = 0.018) and 3 years (P = 0.016 and P = 0.017), respectively. During 3-years follow-up, the 1-, 2- and 3-year survival rate in group A were higher than in group B (P = 0.008, P = 0.021, P = 0.018, respectively), but there was no difference of the incidence of hepatic encephalopathy (P = 0.527).

CONCLUSION

Patients with prior splenectomy have a high incidence of PVT, which potentially increases the risk of recurrent symptoms associated with shunt stenosis or occlusion.

Disparities over Time in Volume, Day of the Week, and Patient Complexity between Paracentesis and Thoracentesis Procedures Performed by Radiologists versus Those Performed by Nonradiologists

PURPOSE

To compare the disparities between the paracenteses and thoracenteses performed by radiologists with those performed by nonradiologists over time. Variables included the volume of procedures, the days of the week, and the complexity of the patient's condition.

MATERIALS AND METHODS

Using carrier claims files for a 5% national sample of Medicare beneficiaries from 2004 to 2016, paracentesis and thoracentesis examinations were retrospectively classified by physician specialty (radiologist vs nonradiologist), day of the week (weekday vs weekend), and the complexity of the patient's condition (using Charlson comorbidity index scores). The Pearson chi-square and independent samples t-test were used for statistical analysis.

RESULTS

Between 2004 and 2016, the proportion of all paracentesis and thoracentesis procedures performed by radiologists increased from 70% to 80% and from 47% to 66%, respectively. Although radiologists increasingly performed more of both services on both weekends and weekdays, the share performed by radiologists was lower on weekends. For most of the first 9 years across the study period, radiologists performed paracentesis in patients with more complex conditions than those treated by nonradiologists, but the complexity of patients' conditions was similar during recent years. For thoracentesis, the complexity of patients' conditions was similar for both specialty groups across the study period.

CONCLUSIONS

The proportion of paracentesis and thoracentesis procedures performed in Medicare beneficiaries by radiologists continues to increase, with radiologists increasingly performing most of both services on weekends. Nonetheless, radiologists perform disproportionately more on weekdays than on weekends. Presently, radiologists and nonradiologists perform paracentesis and thoracentesis procedures in patients with similarly complex conditions. These interspecialty differences in timing and complexity of the patient's condition differ from those recently described for several diagnostic imaging services, reflecting the unique clinical and referral patterns for invasive versus diagnostic imaging services.

Serum 25-hydroxyvitamin D levels and mortality risk in patients with liver cirrhosis: a protocol for a systematic review and meta-analysis of observational studies

BACKGROUND

Liver cirrhosis represents a substantial global burden in terms of morbidity and mortality. Observational studies have reported an increased risk of death with low circulating 25-hydroxyvitamin D concentrations in such patients. Because the occurrence of inadequate vitamin D status is very common in patients with liver cirrhosis, the aim of this study is to conduct a meta-analysis of observational studies in such patients to assess whether vitamin D deficiency increases their risk of mortality.

METHODS

We will search electronic databases (MEDLINE, Embase, Web of Science, CENTRAL and Google Scholar from time of inception until now), conference proceedings and conduct manual searches to identify studies eligible for inclusion. There will be no restrictions based on publication status or language, and the meta-analysis will be reported in accordance with the MOOSE guidelines. We will employ random-effects meta-analysis to assess the relationship between vitamin D deficiency and risk of mortality. Quality of studies will be judged using the Newcastle-Ottawa scale, and between-trial heterogeneity will be evaluated by means of subgroup and sensitivity analyses.

DISCUSSION

The study will assess the effects of serum 25-hydroxyvitamin D concentrations on mortality in patients with liver cirrhosis. The results will be published in a high-quality peer-reviewed journal.

SYSTEMATIC REVIEW REGISTRATION

Prospero CRD42016052007 .

Ultrasound of Diffuse Liver Disease Including Elastography

Diffuse liver disease is a substantial world-wide problem. With the combination of conventional ultrasound of the abdomen and elastography-appropriate staging of the patient can be assessed. This information allows for the detection of fibrosis as well as prognosis, surveillance, and prioritization for treatment. With the potential for reversibility with appropriate treatment, accurate assessment for the stage of chronic liver disease is critical.

AMPK agonist AICAR ameliorates portal hypertension and liver cirrhosis via NO pathway in the BDL rat model

Recent studies have indicated that the Adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) pathway is closely involved in liver fibrosis and other fibrotic diseases. However, whether targeting the AMPK pathway can rescue liver fibrosis and its complications, such as portal hypertension, is unknown. This study aimed to explore the therapeutic value of AICAR (5-aminoimidazole-4-carboxyamide ribonucleoside), an agonist of the AMPK pathway, on liver fibrosis and portal hypertension in bile duct ligation (BDL) rats. In vitro experiments showed that the gene expression levels of TGF-b, a-SMA, and collagen 1 in primary rat hepatic stellate cells (HSCs) were significantly decreased after AICAR treatment. The p-eNOS expression and nitric oxide (NO) production were increased by AICAR administration in sinusoidal endothelial cells (SECs). For in vivo animal studies, AICAR acutely decreased portal pressure in the BDL and CCL4 fibrotic rats, but not in the partial portal vein ligation (PVL) rats, without changes in systemic hemodynamics. It was also observed by using intravital fluorescence microscopy that AICAR led to sinusoidal vasodilation in situ experiment. We propose that the relevant mechanisms may be related to the activation of the AMPK/NO pathway in SECs and that this activation promoted NO production in the liver, thereby promoting hepatic sinusoid microcirculation and decreased intrahepatic resistance. The results were verified using the NO inhibitor L-NAME. Chronic AICAR treatment also showed profound beneficial effects on the BDL model rats. The hemodynamic condition was greatly improved, but the positive effect could be partially blocked by L-NAME. Moreover, AICAR also decreased hepatic fibrogenesis in the BDL rats. KEY MESSAGES: Acute and chronic use of AICAR could alleviate portal pressure without changing systemic hemodynamics. AICAR induced sinusoidal vasodilation by improving NO bioavailability and ameliorating endothelial dysfunction in vivo and in vitro. AICAR could alleviate liver cirrhosis in the BDL model rats.

Influence of Probe Pressure on Ultrasound-Based Shear Wave Elastography of the Liver Using Comb-Push 2-D Technology

It has been postulated that in the liver, applying increased probe pressure during ultrasound-based shear wave elastography (SWE) might lead to a false increase in the SWE result. We aimed to determine the influence of increased intercostal probe pressure when performing SWE of the liver. We also investigated the number of measurements required to achieve technically successful and reliable SWE examinations. This prospective, clinical study included 112 patients and 2240 SWE measurements of the liver. We applied probe pressure intercostally, to reduce the skin-to-liver capsule distance (SCD), which could stabilize the SWE signal and thus increase the number of technically successful measurements. We performed 10 measurements with maximum probe pressure and 10 with normal pressure in each patient. Thus, two analysis groups were compared for differences. Compared with normal pressure, maximum probe pressure significantly reduced the SCD (p < 0.001) and significantly increased the number of technically successful measurements from 981 to 1098, respectively (p < 0.001). The SWE results with normal and maximum probe pressure were 5.96 kPa (interquartile range: 2.41) and 5.45 kPa (interquartile range: 1.96), respectively (p < 0.001). In obese patients, a large SCD poses a diagnostic challenge for ultrasound SWE. We found that maximum intercostal probe pressure could reduce the SCD and increase the number of technically successful measurements, without falsely increasing the SWE result. Only three measurements were required to achieve technically successful and reliable SWE examinations.

Unsolved Issues in the Treatment of Spontaneous Peritonitis in Patients with Cirrhosis: Nosocomial Versus Community-acquired Infections and the Role of Fungi

INTRODUCTION

Historically, spontaneous bacterial peritonitis (SBP) has represented one of the most frequent and relevant infectious complications of advanced liver disease, and this is still valid today. Nevertheless, in recent years the role of fungi as causative pathogens of primary peritonitis in patients with cirrhosis has become not negligible. Another issue is linked with the traditional distinction, instrumental in therapeutic choice, between community-acquired and nosocomial forms, according to the onset. Between these two categories, another one has been introduced: the so-called "healthcare-associated infections".

OBJECTIVE

To discuss the most controversial aspects in the management of SBP nowadays in the light of best available evidence.

METHODS

A review of recent literature through MEDLINE was performed.

RESULTS

The difference between community-acquired and nosocomial infections is crucial to guide empiric antibiotic therapy, since the site of acquisition impact on the likelihood of multidrug-resistant bacteria as causative agents. Therefore, third-generation cephalosporins cannot be considered the mainstay of treatment in each episode. Furthermore, the distinction between healthcare-associated and nosocomial form seems very subtle, especially in areas wherein antimicrobial resistance is widespread, warranting broad-spectrum antibiotic regimens for both. Finally, spontaneous fungal peritonitis is a not common but actually underestimated entity, linked to high mortality. Especially in patients with septic shock and/or failure of an aggressive antibiotic regimen, the empiric addition of an antifungal agent might be considered.

CONCLUSION

Spontaneous bacterial peritonitis is one of the most important complications in patients with cirrhosis. A proper empiric therapy is crucial to have a positive outcome. In this respect, a careful assessment of risk factors for multidrug-resistant pathogens is crucial. Likewise important, mostly in nosocomial cases, is not to overlook the probability of a fungal ascitic infection, namely a spontaneous fungal peritonitis.

Endovascular Treatment for Variceal Hemorrhage: TIPS, BRTO, and Combined Approaches

Variceal hemorrhage is a feared complication of portal hypertension, with high rates of morbidity and mortality. Optimal management requires a thoughtful, multidisciplinary approach. In cases of refractory or recurrent esophageal hemorrhage, endovascular approaches such as transjugular intrahepatic portosystemic shunt (TIPS) have a well-defined role. For hemorrhage related to gastric varices, the optimal treatment remains to be established; however, there is increasing adoption of balloon-occluded retrograde transvenous obliteration (BRTO). This article will review the concept, history, patient selection, basic technique, and outcomes for TIPS, BRTO, and combined TIPS + BRTO procedures for variceal hemorrhage.