Computer clinical decision support that automates personalized clinical care: a challenging but needed healthcare delivery strategy.

How to deliver best care in various clinical settings remains a vexing problem. All pertinent healthcare-related questions have not, cannot, and will not be addressable with costly time- and resource-consuming controlled clinical trials. At present, evidence-based guidelines can address only a small fraction of the types of care that clinicians deliver. Furthermore, underserved areas rarely can access state-of-the-art evidence-based guidelines in real-time, and often lack the wherewithal to implement advanced guidelines. Care providers in such settings frequently do not have sufficient training to undertake advanced guideline implementation. Nevertheless, in advanced modern healthcare delivery environments, use of eActions (validated clinical decision support systems) could help overcome the cognitive limitations of overburdened clinicians. Widespread use of eActions will require surmounting current healthcare technical and cultural barriers and installing clinical evidence/data curation systems. The authors expect that increased numbers of evidence-based guidelines will result from future comparative effectiveness clinical research carried out during routine healthcare delivery within learning healthcare systems.

Intrahepatic CD206+ macrophages contribute to inflammation in advanced viral-related liver disease.

BACKGROUND & AIMS: Liver inflammation is key in the progression of chronic viral hepatitis to cirrhosis and hepatocellular carcinoma. The magnitude of viral replication and the specific anti-viral immune responses should govern the degree of inflammation, but a direct correlation is not consistently found in chronic viral hepatitis patients. We aim to better define the mechanisms that contribute to chronic liver inflammation. METHODS: Intrahepatic CD14+ myeloid cells from healthy donors (n=19) and patients with viral-related liver cirrhosis (HBV, HBV/HDV or HCV; n=15) were subjected to detailed phenotypic, molecular and functional characterisation. RESULTS: Unsupervised analysis of multi-parametric data showed that liver disease was associated with the intrahepatic expansion of activated myeloid cells mainly composed of pro-inflammatory CD14+HLA-DRhiCD206+ cells, which spontaneously produced TNFα and GM-CSF. These cells only showed heightened pro-inflammatory responses to bacterial TLR agonists and were more refractory to endotoxin-induced tolerance. A liver-specific enrichment of CD14+HLA-DRhiCD206+ cells was also detected in a humanised mouse model of liver inflammation. This accumulation was abrogated following oral antibiotic treatment, suggesting a direct involvement of translocated gut-derived microbial products in liver injury. CONCLUSIONS: Viral-related chronic liver inflammation is driven by the interplay between non-endotoxin-tolerant pro-inflammatory CD14+HLA-DRhiCD206+ myeloid cells and translocated bacterial products. Deciphering this mechanism paves the way for the development of therapeutic strategies specifically targeting CD206+ myeloid cells in viral-related liver disease patients. Lay summary: Viral-related chronic liver disease is driven by intrahepatic pro-inflammatory myeloid cells accumulating in a gut-derived bacterial product-dependent manner. Our findings support the use of oral antibiotics to ameliorate liver inflammation in these patients.

Toll-like receptor 8 agonist and bacteria trigger potent activation of innate immune cells in human liver.

The ability of innate immune cells to sense and respond to impending danger varies by anatomical location. The liver is considered tolerogenic but is still capable of mounting a successful immune response to clear various infections. To understand whether hepatic immune cells tune their response to different infectious challenges, we probed mononuclear cells purified from human healthy and diseased livers with distinct pathogen-associated molecules. We discovered that only the TLR8 agonist ssRNA40 selectively activated liver-resident innate immune cells to produce substantial quantities of IFN-γ. We identified CD161(Bright) mucosal-associated invariant T (MAIT) and CD56(Bright) NK cells as the responding liver-resident innate immune cells. Their activation was not directly induced by the TLR8 agonist but was dependent on IL-12 and IL-18 production by ssRNA40-activated intrahepatic monocytes. Importantly, the ssRNA40-induced cytokine-dependent activation of MAIT cells mirrored responses induced by bacteria, i.e., generating a selective production of high levels of IFN-γ, without the concomitant production of TNF-α or IL-17A. The intrahepatic IFN-γ production could be detected not only in healthy livers, but also in HBV- or HCV-infected livers. In conclusion, the human liver harbors a network of immune cells able to modulate their immunological responses to different pathogen-associated molecules. Their ability to generate a strong production of IFN-γ upon stimulation with TLR8 agonist opens new therapeutic opportunities for the treatment of diverse liver pathologies.

IL-7 licenses activation of human liver intrasinusoidal mucosal-associated invariant T cells.

Human mucosal-associated invariant T (MAIT) cells are a T cell population characterized by the expression of a semi-invariant TCR capable of recognizing bacterial products in the context of MR1. MAIT cells are enriched in the human liver, which is constantly exposed to bacterial products from the intestine. Whether this specific parenchymal localization influences their function remains unknown. We analyzed MAIT cells resident in the vascular bed of livers and showed that they represented the majority of T cells expressing NK markers and the dominant IL-17A(+) T cell subset in the human liver sinusoids. In comparison with MAIT cells purified from peripheral blood, intrasinusoidal MAIT cells expressed markers of T cell activation; however, TCR-mediated cytokine production was equally suppressed in both circulating and intrasinusoidal MAIT cells. MAIT cells also expressed high levels of IL-7R, and we showed that IL-7, a cytokine produced by hepatocytes during inflammation, regulated TCR-mediated activation of MAIT cells, licensing them to dramatically increase Th1 cytokines and IL-17A production. Our quantitative and functional data indicate that MAIT cells are a specialized cell population highly adapted to exert their immune functions in the vascular network of the liver.

Licensing virus-specific T cells to secrete the neutrophil attracting chemokine CXCL-8 during hepatitis B virus infection.

T cell functional plasticity helps tailor antiviral immunity during different phases of infections. We tested whether, during different phases of HBV infection, virus-specific T cells can acquire specific proinflammatory functions that could drive granulocyte/mononuclear cell liver infiltration. Multifunctional analysis of HBV-specific T cells during acute and chronic HBV infection revealed that HBV-specific T cells had the capacity to produce the neutrophil chemokine CXCL-8 but not IL-17. CXCL-8 producing T cells were detectable in the liver of chronic HBV patients with active hepatitis; while in acute HBV patients CXCL-8 production by T cells was temporally limited to the acute phase of disease, concomitant with the peak of liver inflammation. Characterization of the conditions necessary for the development of CXCL-8 producing T cells showed a requirement for IL-7 and IL-15 during T cell expansion. These data show that functional plasticity of virus-specific T cells spontaneously occurs during HBV infection and that an environment rich IL-7 and IL-15 can license T cells with the ability to produce CXCL-8 and potentially influence liver pathology.

Inflammatory tumour microenvironment is associated with superior survival in hepatocellular carcinoma patients.

BACKGROUND & AIMS: Hepatocellular carcinoma (HCC) is an aggressive malignancy with few treatment options. As the status of the tumour immune microenvironment can affect progression of established tumours, we evaluated potential immune mechanisms associated with survival in HCC. METHODS: Immune gene expression profiles were analyzed in tumour and non-tumour liver tissues from resected HCC patients using quantitative PCR and immunohistochemistry. Tumour-infiltrating leukocytes (TILs) were isolated to verify the expression of immune genes and to identify proliferating TILs. These parameters were analyzed statistically in relation with patient survival and tumour phenotype (apoptosis and proliferation). RESULTS: The immune microenvironment within tumours was found to be heterogeneous, although globally more inert compared to the adjacent non-tumour liver tissue. Univariate analysis in 61 patients identified a group of innate immune genes whose expression within tumours is positively associated with patient survival. TNF, IL6 and CCL2 are the most significant genes, with TNF being an independent predictor of survival in multivariate analysis. The gene set includes macrophage and NK-associated molecules such as TLR4, TLR3, CCR2, NCR3. Most of these molecules are expressed by TILs. Importantly, proliferating immune cells, predominantly NK and T cells, are present in tumours of patients with longer survival, and exclusively in areas devoid of proliferating tumour cells. NK and CD8(+) T cell densities are correlated positively with tumour apoptosis, and negatively with tumour proliferation. CONCLUSIONS: Hence, an inflammatory immune microenvironment within HCC tumours could be an important means to control tumour progression via TIL activation and proliferation.

Modified rendezvous technique in management of biliary leak in right lobe live donor liver transplant recipients.

Biliary complication is the Achilles' heel for live donor liver transplant. Bile leak is particularly difficult to manage as the anastomotic site was often angled acutely. We described a patient with bile leak managed by a modified rendezvous technique whereby the endoscopist and radiologist work simultaneously under fluoroscopy. Unlike the traditionally described rendezvous technique where the grasping of guidewire occurred at the duodenum, the grasping of guidewire occurred at the biloma in this modified technique. Insertion of biliary stent could then be performed over the guidewire through the duodenoscope. The bile leak resolved after keeping the biliary stents in situ for 12 months.

Profile of tumor antigen-specific CD8 T cells in patients with hepatitis B virus-related hepatocellular carcinoma.

BACKGROUND & AIMS: Tumor and viral antigens are expressed by hepatocellular carcinoma (HCC) in patients with chronic hepatitis B, but little is known about the immunodominance and function of tumor- and virus-specific CD8+ T cells in these patients. METHODS: HLA-A2-restricted T-cell responses to 16 tumor antigens and hepatitis B virus (HBV) proteins were tested using 49 previously described epitopes. Cells from 30 HLA-A2+, HBV-infected patients (10 with HCC, 10 with HBV cirrhosis, and 10 HBV but no cirrhosis) were analyzed, after expansion, by enzyme-linked immunosorbent spot (ELISPOT). Interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha, and interleukin (IL)-2 production, as well as expression of the degranulation marker CD107a on tumor-specific CD8+ T cells, were evaluated. RESULTS: Cells from all groups had tumor-specific responses. The tumor antigens NY-ESO-1 and SSX-2 were most frequently targeted and were immunogenic in the HLA-A2 subtypes that are characteristic of Asian ethnicity. Tumor-specific T cells had low affinities; T cells from non-HCC patients were polyfunctional (IFN-gamma+, TNF-alpha+, CD107a+) and those from HCC patients displayed an exhausted phenotype (IFN-gamma+, CD107a+). Programmed Death 1 (PD-1) was expressed at higher levels on T cells from tumor and liver than peripheral blood from HCC patients and might contribute to T-cell exhaustion. Blocking PD-1/PD-L1 increased the frequency of tumor-specific T cells in HCC patients but did not restore T cell function. CONCLUSIONS: Patients with or without HCC have a quantitative and functional hierarchy of tumor-specific T cells. HLA-A2-restricted T cells from HCC patients target NY-ESO-1, but exist in an exhausted state that might require additional activation to restore function.

Living donor liver transplantation for hepatocellular carcinoma: a single centre experience.

BACKGROUND: The indications of liver transplantation in hepatocellular carcinoma (HCC) are evolving. With the advent of living donor liver transplantation (LDLT), there is a renewed interest in this procedure for tumors beyond the standard Milan criteria. METHODS: We retrospectively analyzed the outcome of 28 patients who underwent LDLT for HCC in one institution. Survival analysis was done using the Kaplan-Meier method. RESULTS: Of the 28 patients, 9, 12 and 7 had Child's A, B and C cirrhosis respectively; 26 (93%) had underlying hepatitis B or C. Nineteen patients (68%) had tumors exceeding the Milan criteria. Postoperative (within 90 days) mortality and morbidity rates were 2/28 (7%) and 7/28 (25%) respectively. The actuarial overall 1-year, 2-year and 3-year survival rates were 76%, 76% and 51%, respectively. The actuarial 1-year, 2-year and 3-year recurrence free survival rates (computed by censoring the data of patients who died of causes other than HCC recurrence) were 88%, 82% and 70%, respectively. Although the survival rates were better for tumors within the Milan criteria than those exceeding them, the difference was not significant. CONCLUSIONS: LDLT is an effective modality in the treatment of HCC in patients with liver cirrhosis. It may also provide an opportunity for potential cure to patients with tumors beyond Milan criteria.

Liver support devices.

PURPOSE OF REVIEW: Liver support devices are used either as a bridge to liver transplantation or liver recovery in patients with acute or acute-on-chronic liver failure. The review analyzes the recent literature and asks if the current enthusiasm for these devices is justified. RECENT FINDINGS: Many liver support devices exist and are discussed. Clinical data on artificial devices are rapidly emerging, especially on the molecular adsorbents recirculating system, and fractionated plasma separation and adsorption (Prometheus). While hepatic encephalopathy is improved by the molecular adsorbents recirculating system and probably Prometheus too, neither system has been shown to improve survival. Less clinical data exist for bioartificial support devices. These may use human hepatocytes, such as the extracorporeal liver assist device, although most devices use porcine hepatocytes, such as HepatAssist. SUMMARY: Enthusiasm in liver support devices is justified as many nonrandomized studies have suggested some biochemical and clinical benefits. The results of several ongoing multicenter randomized controlled trials are anxiously awaited. Meanwhile, because mortality without liver transplantation remains high despite the use of liver support devices, these devices should only be used in the research setting or by experts proficient in their use and as a bridge to liver transplantation rather than liver recovery.

Lactate, procalcitonin, and amino-terminal pro-B-type natriuretic peptide versus cytokine measurements and clinical severity scores for prognostication in septic shock.

The biomarkers lactate, procalcitonin, and amino-terminal pro-B-type natriuretic peptide (NT-proBNP) are often promoted as being useful for prognostication in septic shock. This study aimed to compare the prognostic utility of these biomarkers with each other and with cytokine measurements and clinical severity scores, and to assess how these biomarkers may be combined to improve their prognostic utility. Seventy-two patients with septic shock were studied. The biomarkers were measured on the first 3 days of stay in the intensive care unit together with serum IL-1beta, IL-6, IL-10, and TNF-alpha levels. Although elevated baseline lactate levels predicted 28-day mortality, elevated procalcitonin and NT-proBNP levels were only predictive from days 2 and 3, respectively. The prognostic utility of baseline lactate levels was poorer than that of baseline cytokine levels, the Acute Physiology and Chronic Health Evaluation II score, and the Sequential Organ Failure Assessment score. However, a rising trend in lactate and procalcitonin levels between days 1 and 2 had superior prognostic utility compared with absolute levels. Indeed, using multivariate analysis, the presence of a concurrent increase in both lactate and procalcitonin levels between days 1 and 2 superseded all cytokine measurements and clinical severity scores as the sole independent predictor of 28-day mortality. In conclusion, elevated baseline lactate levels offer superior prognostic accuracy to baseline procalcitonin levels, which in turn are superior to NT-proBNP levels. To improve their prognostic utility beyond those of cytokine measurements and clinical severity scores, serial lactate and procalcitonin measurements may be combined.

Spontaneous bacterial peritonitis from Salmonella: an unusual bacterium with unusual presentation.

Spontaneous bacterial peritonitis (SBP) is a common cause of morbidity and mortality in patients with advanced cirrhosis and portal hypertension. While gram-negative rods and Enterococcus species are the common offending organisms, Salmonella has also been recognized as a rare and atypical offending organism. Atypical features of Salmonella SBP include both its occurrence in cirrhotic patients with immunosuppressive state and its lack of typical neutroascitic response. Diagnosis is often delayed as it requires confirmation from ascitic fluid culture. We report a case of Salmonella SBP occurring in a patient with decompensated cryptogenic cirrhosis with concurrent low-grade non-Hodgkin lymphoma and prior treatment with rituximab. Physicians should be aware of the atypical presentation, especially in cirrhotic patients who are immunosuppressed.

Adult living donor liver transplantation in Singapore: the Asian centre for liver diseases and transplantation experience.

INTRODUCTION: Living donor liver transplantation (LDLT) has progressed dramatically in Asia due to the scarcity of cadaver donors and is increasingly performed in Singapore. The authors present their experience with adult LDLT. MATERIALS AND METHODS: Adult LDLTs performed at the Asian Centre for Liver Diseases and Transplantation, Singapore from 20 April 2002 until 20 March 2006 were reviewed. All patients received right lobe grafts and were managed by the same team throughout this period. Data were obtained by chart review. This study presents both recipient and donor outcomes in a single centre. RESULTS: A total of 65 patients underwent LDLT. Forty-three were genetically related while 22 were from emotionally-related donors. The majority were chronic liver failure while 14% were acute. The most common indication for LDLT was end-stage liver disease due to hepatitis B virus. A total of 22 patients with hepatoma were transplanted and overall 1-year disease specific survival was 94.4%. The mean model for end-stage liver disease (MELD) score was 17.4 +/- 9.4 (range, 6 to 40). Six patients had preoperative molecular adsorbent recycling system (MARS) dialysis with 83% transplant success rate. The mean follow-up was 479.2 days with a median of 356 days. One-year overall survival was 80.5%. There was 1 donor mortality and morbidity rate was 17%. Our series is in its early stage with good perioperative survival outcome with 1-month and 3-month actuarial survival rates of 95.4% and 87.3% respectively. CONCLUSION: The study demonstrates that LDLT can be done safely with good results for a variety of liver diseases. However, with dynamically evolving criteria and management strategies, further studies are needed to maximise treatment outcome.

Pre-transplant optimization by Molecular Adsorbent Recirculating System in patients with severely decompensated chronic liver disease.

BACKGROUND: The outcome of liver transplantation (LT) is influenced by the recipient's clinical condition. In a retrospective observational study, we evaluated the role of pre-LT Molecular Adsorbent Recirculating System (MARS) treatment in improving the clinical status and thereby the outcome of patients with chronic liver disease and severe hepatic decompensation. METHODS: Between March 2002 and September 2006, 70 patients with end-stage chronic liver disease underwent living-donor LT (LDLT). Of these, 9 (13%) patients with severely decompensated liver function (serum bilirubin> 350 micromol/L [20 mg/dL] and/or hepatic encephalopathy > or = grade 2) received pre-LT MARS treatment. RESULTS: The median MELD score was 33 (range, 26-47). A median of 2 (range, 1-6) sessions (8 hour/session) of MARS dialysis was performed per patient. MARS treatment was associated with reduction in serum bilirubin, creatinine and ammonia levels and no procedure-related complications. CONCLUSION: Pre-LT MARS is well tolerated and results in reduction of jaundice and improvement in renal function and may be useful in the management of patients with severe hepatic decompensation.

Long term outcome and prognostic factors for large hepatocellular carcinoma (10 cm or more) after surgical resection.

BACKGROUND: Surgical resection is the standard treatment for hepatocellular carcinoma (HCC). However, the role of surgery in treatment of large tumors (10 cm or more) is controversial. We have analyzed, in a single centre, the long-term outcome associated with surgical resection in patients with such large tumors. METHODS: We retrospectively investigated 166 patients who had undergone surgical resection between July 1995 and December 2006 because of large (10 cm or more) HCC. Survival analysis was done using the Kaplan-Meier method. Prognostic factors were evaluated using univariate and multivariate analyses. RESULTS: Of the 166 patients evaluated, 80% were associated with viral hepatitis and 48.2% had cirrhosis. The majority of patients underwent a major hepatectomy (48.2% had four or more segments resected and 9% had additional organ resection). The postoperative mortality was 3%. The median survival in our study was 20 months, with an actuarial 5-year and 10-year overall survival of 28.6% and 25.6%, respectively. Of these patients, 60% had additional treatment in the form of transarterial chemoembolization, radiofrequency ablation or both. On multivariate analysis, vascular invasion (P < 0.001), cirrhosis (P = 0.028), and satellite lesions/multicentricity (P = 0.006) were significant prognostic factors influencing survival. The patients who had none of these three risk factors had 5-year and 10-year overall survivals of 57.7% each, compared with 22.5% and 19.3%, respectively, for those with at least one risk factor (P < 0.001). CONCLUSIONS: Surgical resection for those with large HCC can be safely performed with a reasonable long-term survival. For tumors with poor prognostic factors, there is a pressing need for effective adjuvant therapy.

The role of liver transplantation for hilar cholangiocarcinoma.

BACKGROUND: Hilar cholangiocarcinoma is a devastating disease. Surgery is the only potentially curative modality. However, the results of surgical resection for hilar cholangiocarcinomas are disappointing. The introduction of liver transplantation for this condition has brought new hope for the management of this disease. The aim of this review is to discuss the role of liver transplantation in this disease. DATA SOURCES: A MEDLINE search was conducted for the articles on liver transplantation for hilar cholangiocarcinoma. Their results have been compiled and compared with the existing literature on resection for this disease. RESULTS: The earlier series on liver transplantation for hilar cholangiocarcinoma were not encouraging because of poor patient selection. The Mayo Clinic protocol of neoadjuvant chemoradiation followed by liver transplantation has shown remarkable success (survival at 1-, 3-, and 5-year post-transplantation being 92%, 82%, and 82%, respectively). With better patient selection and integration of neoadjuvant chemoradiation, the long-term survival is superior to that of the patients who undergo resection, as shown by the published literature on resection. The limitations of organ availability can be overcome by the living donor liver transplantation programme. This review article discusses the rationale, pros and cons of liver transplantation vis-á-vis resection for hilar cholangiocarcinoma. CONCLUSIONS: Liver transplantation, especially living donor liver transplantation, is a new and exciting alternative to resection for hilar cholangiocarcinoma. Integration of neoadjuvant chemoradiation has the potential to further improve the curative potential of liver transplantation. The strategy of combining neoadjuvant chemoradiation and liver transplantation brings new hope for the treatment of this difficult disease.

MARS: a futile tool in centres without active liver transplant support.

BACKGROUND AND AIM: Studies on Molecular Adsorbent Recycling Systems (MARS) showed inconclusive survival benefits. PATIENTS AND METHOD: We evaluated the efficacy of MARS for patients with either acute liver failure (ALF) or acute-on-chronic liver failure (AoCLF) at our centre, from February 2002 till April 2006 retrospectively. RESULTS: Fifty ALF patients underwent median (range) three (1-10) sessions of MARS. Acute exacerbations of chronic hepatitis B (n=26) and drug-induced liver injury (n=12) were the commonest causes. Living donors were available in 6, 2 paediatric patients underwent left lobe and four adults underwent right lobe living donor liver transplant. Among the 44 ALF patients without a suitable living donor, one underwent deceased donor liver transplant and survived, another 19-year-old male with acute exacerbations of chronic hepatitis B recovered without transplant, and the rest died. Twenty-six had AoCLF and underwent four (1-10) MARS sessions. Sepsis (n=16) and upper gastrointestinal bleeding (n=4) were the commonest precipitating factors. None had a suitable living or deceased donor, suitable for transplantation during their hospitalization. Only one of 26 AoCLF patients survived the hospitalization, but the survivor died of sepsis 1 month later. CONCLUSION: In this non-randomized study, survival after MARS was related to the availability of transplant, and in patients where living or deceased donor transplant was unavailable, MARS was of little benefit. Randomized-controlled trials on MARS((R)) are urgently needed to clarify its clinical utility.

Evaluating the pharmacoeconomic effect of adding tiotropium bromide to the management of chronic obstructive pulmonary disease patients in Singapore.

OBJECTIVE: To perform a pharmacoeconomic analysis on the treatment of chronic obstructive pulmonary disease (COPD) with the addition of tiotropium bromide. METHODS: Pharmacoeconomic modeling was performed utilizing the efficacy of tiotropium bromide from the literature on different settings and severity of COPD. Reductions in exacerbations, hospitalizations, and number of exacerbation days per year were derived from these studies. Cost of drug treatment, exacerbations, hospitalization, and loss of income were derived from local data in Singapore and reported in Singapore dollars (US$1=S$1.71). A model was constructed to calculate the impact of one-year treatment with tiotropium bromide, and the results were reported for the total incremental cost per year, cost per year needed to reduce one hospitalization in one year, and cost-savings from hospitalizations in one year. Sensitivity analysis were performed for different number of patients treated per year, differing cost of hospitalization, different cost for tiotropium bromide, different impact of tiotropium bromide on clinical outcomes, and the different amount of substitution drug utilized in the comparator group. RESULTS: Using the different clinical effects and looking at the impact on treating 1000, 2000, and 10,000 patients per year, most of the results showed a high level of decrease in overall cost per year that ranged from S$145.40 to S$840.37 per patient treated. Cost per year needed to reduce one hospitalization in one year ranged from S$3217.31 to S$18,148.92. Cost-savings from hospitalizations in one year per patient treated ranged from $57.16 to $322.49. This may contribute as high as 83% of the overall cost saving. Sensitivity analysis supports the cost savings finding. CONCLUSION: Adding tiotropium bromide for severe COPD patients would lead to a significant cost savings for the economy.