Vol. 13 Issue 2
On the cover: Contrast-enhanced multidetector-row computed tomography (CE-MDCT) image of the heart reformatted on frontal (A) and sagittal (B) plane. 3D volume-rendered (C) and multi-intensity projection (D) images of celiac trunk reformatted on coronal plane
Nonalcoholic fatty liver disease (NAFLD) is an alarming public health problem. The disease is one of the main causes of chronic liver disease worldwide and is directly linked to the increased prevalence of obesity and type 2 diabetes mellitus (T2DM) in the general population. The worldwide prevalence of NAFLD has been estimated at 20-30%, but the prevalence is unknown in the Americas because of a lack of epidemiological studies. However, given the trends in the prevalence of diabetes and obesity, the prevalence of NAFLD and its consequences are expected to increase in the near future. The aim of the present study is to present the current data on the prevalence of NAFLD in the Americas. We performed an electronic search of the main databases from January 2000 to September 2013 and identified 356 reports that were reviewed. We focused on the epidemiology and prevalence of known NAFLD risk factors including obesity, T2DM, and the metabolic syndrome (MS). The prevalence of the MS was highest in the United States, Mexico, Costa Rica, Puerto Rico, Chile, and Venezuela. In addition, Puerto Rico, Guyana, and Mexico have the highest prevalence of T2DM in the Americas, while USA has the most people with T2DM. In conclusion, the prevalence rates of NAFLD and obesity were highest in the United States, Belize, Barbados, and Mexico.
A limited number of medications are typically considered for the management of hepatic encephalopathy occurring as a complication of transjugular intrahepatic portosystemic shunt (TIPS) placement. Multiple alternative compounds aimed at disrupting ammoniagenesis are or will soon be available, though their use tends to be limited by a lack of large data sets and of clinical awareness. In this review, we provide a targeted overview of the mechanisms and availability of five anti-ammoniagenic compounds (sodium phenylbutyrate, glycerol phenylbutyrate, sodium benzoate, L-ornithine L-aspartate, and ornithine phenylacetate) identified as possibly useful alternative therapeutic agents for cirrhotic encephalopathy. Three of these medications have been FDA approved for use in congenital urea cycle disorders only, while two are under active investigation for use in cirrhotic patients. In spite of limitations posed by cost and comorbidities, familiarity with these options may prove beneficial in cases refractory to conventional management.
Hepatitis B is a chronic viral infection of the liver leading to complications including cirrhosis and hepatocellular carcinoma. The leading cause of acquisition is vertical transmission from an infected mother to the newborn. Despite newborn immunoprophylaxis, vertical transmission may still occur in 1-14%. The aim of this article is to provide a concise review of the mechanisms and risk factors involved in vertical transmission, as well as prophylactic strategies using immunoprophylaxis and antiviral medications. Mechanisms of vertical transmission include intrauterine and perinatal transfer of virus. High HBV viral load and presence of HBeAg increases risk of transmission. Combination vaccine and hepatitis B immunoglobulin given at birth reduces risk of transmission, as does HBIG given to mothers in the third trimester. Three antivirals have been studied in pregnancy: lamivudine, telbivudine, and tenovofir. All have shown significant reduction in viral loads and vertical transmission and have favorable safety profiles. In conclusion, HBV vertical transmission is preventable through use of immunoprophylaxis and antiviral medications. Recommendation for antiviral use in third trimester in mothers whose HBV VL is greater than 1 x 106 copies/mL.
Background and aim. In patients with chronic hepatitis C receiving Peg interferon/ribavirin (PEG-IFN/RBV) who do not achieve ? 2log-reduction in HCV-RNA at week 12 (null responders, NR) and in those with ? 2log-decrease but detectable at week 24 (partial responders, PR) the probability to achieve the sustained virological response (SVR) is almost null. The aim of this study was to investigate the efficacy of individualized schedule of progressively increased RBV doses in the setting of PEG-IFN/RBV treatment. Material and methods. PR or NR to PEG-IFN/RBV instead of discontinuing treatment were enrolled to receive increasing doses of RBV until a target theoretical concentration ([tRBV]) of ? 15 ?mol/L (by pharmacokinetic formula based on glomerular filtration rate). HCV-RNA was assessed every 4 weeks and, if detectable, RBV dose was gradually increased until negativization. Twelve weeks later, patients with detectable HCV-RNA discontinued therapy while those with undetectable HCV-RNA continued for further 48 weeks. Results. Twenty genotype-1 patients (8 NR and 12 PR) were enrolled. After 12 weeks 9 (45%) were still HCV-RNA positive and were discontinued, while remaining 11 had undetectable HCV-RNA. One stopped treatment for side effects. Ten completed treatment. Five (all PR) achieved SVR. Side effects incidence was similar to that observed during PEG-IFN/RBV. Conclusions. In conclusion, RBV high doses, according to individualized schedule, increase SVR in PR on a similar extent to that of triple therapy but without increase of side effects. Such treatment should be considered in PR with no access or intolerant to protease inhibitors (PI).
Background and aim. Hepatocellular carcinoma (HCC) is a frequent cancer. Its prognosis is highly dependent on early diagnosis. Patients at risk for developing HCC should be enrolled in a surveillance programme. Nevertheless, many patients at risk are not regularly screened. We aimed at exploring the characteristics that affect enrolment in a surveillance programme. Material and methods. The characteristics of the patients included in the prospective Bern HCC cohort between August 2010 and August 2011 were analysed according to their participation in a surveillance programme. Results. Among the 82 patients included in the cohort during this period of time, 48 were in a surveillance program before the diagnosis of HCC. Thirty five percent of cirrhotic patients were not screened. Age, sex, level of education, Child-Pugh status and MELD score were similar between the patients who were screened and those who were not screened. Patients with a private insurance and patients treated by a liver specialist were more frequently enrolled in a surveillance program. Sixty seven percent of the screened patients were eligible for curative treatment whereas only 15% of the non-screened patients were. Conclusions. In conclusion the surveillance of patients at risk for developing HCC increases their chances to be diagnosed at an early stage to allow curative treatment. More than one third of cirrhotic patients were not regularly screened. Patients with chronic liver disease should be referred to identify those at risk and enrol them in a surveillance program.
Background. Incidental hepatocellular carcinoma (iHCC) generates uncertainty over risk of recurrence after liver transplantation (LT). Aim. To compare recurrence between iHCC and confirmed HCC diagnosed prior to transplant based on imaging criteria (cHCC). Material and methods. Fifty-four HCC patients were analyzed from a series of 309 consecutive adult transplanted patients. We developed a recurrence predicting score (RPS) applying ORs based on pathologic risk variables. Results. Incidence of iHCC was 4.8% (n = 15) and overall recurrence 12.9% (cHCC 15.4% and iHCC 7%; P = 0.39). Variables included in the RPS were: microvascular invasion OR 17.8 (1.78-178.97; P = 0.014: 2 points), neural invasion OR 15.5 (1.13-212.17; P = 0.04: 1.5 points), nuclear grade > II OR 9.3 (1.17-74.84; P = 0.035: 1 point), and beyond Up-to 7 criteria OR 13.1 (1.66-103.67; P = 0.015: 1.5 points). Two risk groups were identified: low risk for recurrence (0-1 point) and intermediate-high risk groups (2-6 points). Low risk category remained an independent predictor of recurrence: OR 0.11 (0.01-0.67; P = 0.017); AUROC of 0.75 (0.54-0.96). A tendency towards more patients categorized as low risk group among iHCC patients was observed (69.2%; P = 0.13). Conclusions. In this series iHCC was not associated to lower risk of recurrence when compared to cHCC. We propose application of an RPS as a clinical tool for recurrence risk estimation.
The optimal timing to treat recurrent hepatitis-C virus (HCV) after liver transplantation (LT) remains uncertain. We compared the outcome of early (acute phase) and deferred (chronic phase) antiviral treatment for recurrent HCV infection in this population. Consecutive HCV genotype-1 infected LT patients receiving antiviral therapy between 2001-2010 were retrospectively classified according to histology at treatment start into the early or deferred treatment group. Measured endpoints included sustained virological response (SVR) rates and long-term survival. The study cohort comprised 105 patients: 60 (57%) received early treatment (ET) and 45 (43%) deferred treatment (DT). The median interval from LT to antiviral start was 3 (1-9) and 18 months (11-74) in ET and DT respectively. The SVR rate was similar in both treatment groups (23% ET and 36% DT; p = 0.27). After a median follow-up of 5.8 years, all-cause and liver-related mortality were similar in both groups. Variables independently associated with mortality included pre-treatment bilirubin > 2 mg/dL (HR 6.1, 95%CI: 2.8-13.7; p < 0.001), donor age > 60 (HR 3.1, 95%CI: 1.4-6.7; p = 0.01), and failure to achieve SVR (HR 10.3, 95%CI: 1.3-18.3; p = 0.03). In conclusion, early treatment of recurrent HCV is safe, but does not lead to higher SVR rates. In HCV-infected LT recipients, elevated bilirubin, older donor age, and failure to achieve SVR are independently associated with increased mortality.
Introduction. Drug-induced liver injury (DILI) remains a major problem for drug development and represents a challenging diagnosis for clinicians. The absence of specific biomarkers for diagnosing DILI precludes the availability of reliable data on the epidemiology of the disease. In this study we aimed to describe the features of idiosyncratic hepatotoxicity reports in Latin American countries. Material and methods. A literature search was performed using the online version of MEDLINE, EMBASE, Scopus, Google Scholar and specific data bases from Latin America (LA) (Scielo, Lilacs) to identify any case report or case series of published DILI from 1996 to 2012. From 1996 to 2012, a total of 176 patients with DILI were published in LA, involving 53 suspicious drugs. The median age in the adult population of these patients was 55 years (17-82) with prevalence of women (67%). Among main therapeutic classes, the rank order was led by non-steroidal anti-inflammatory (61 cases) and systemic antibacterial drugs (37 cases). Nimesulide was the individual drug responsible for the highest number of cases (53), followed by cyproterone acetate (18), nitrofurantoin (17), antituberculous drugs (13) and flutamide (12). Thirty two percent of published cases evolved to acute liver failure (ALF), and half of the subjects required liver transplantation or eventually died. Conclusions. This study represents the first structured attempt to assess the spectrum of DILI profile in LA. The establishment of a Latin American registry to collect prospective DILI cases using a standardized protocol will advance our knowledge about idiosyncratic DILI in this region.
Aim. The aim of this study was to assess the effects of the molecular absorbent recirculating system (MARS) on patients with acute liver failure (ALF) and liver failure with cirrhosis (AoCLF) as well as in cholestatic patients with intractable pruritus in a Mexican population. Material and methods. From August 2003 to December 2011, MARS was used in 38 patients with ALF, 15 patients with AoCLF, and 17 cholestatic patients with intractable pruritus. The patients were examined using a standard liver function test and for vital signs, presence of ascites and encephalopathy before and after each treatment. The therapeutic response, patient status, follow-up status, and need for liver transplantation were determined. Results. Seventy-nine MARS procedures were performed. MARS was used for ALF in 54.3% of patients, AoCLF in 24.2%, and cholestatic disease in 21.5%. There were significant improvements in serum bilirubin (p = 0.000), aspartate aminotransferase (p = 0.000), alanine aminotransferase (p = 0.030), gamma-glytamyl transpeptidase (p = 0.044), alkaline phosphatase (p = 0.006), and encephalopathy grade (p = 0.000). Thirty-eight ALF patients were listed for emergency liver transplantation and treated with MARS; 20 of these patients died on a waiting list, 18 survived. only four underwent liver transplantation and 14 (37%) recovered without transplantation after the MARS procedure. Conclusion. MARS is a safe and effective procedure, especially for ALF patients. Our results suggest that MARS therapy can contribute to native liver recovery in ALF patients.
The diagnosis of drug induced liver injury (DILI) is based primarily on the exclusion of alternative causes. To assess the frequency of alternative causes in initially suspected DILI cases, we searched the Medline database with the following terms: drug hepatotoxicity, drug induced liver injury, and hepatotoxic drugs. For each term, we used the first 100 publications. We reviewed references, selected those reports relevant to our study, and retrieved finally 15 publications related to DILI and alternative causes. A total of 2,906 cases of initially assumed DILI were analyzed in these 15 publications, with diagnoses missed in 14% of the cases due to overt alternative causes. In another 11%, the diagnosis of DILI could not be established because of confounding variables. Alternative diagnoses included hepatitis B, C, and E, CMV, EBV, ischemic hepatitis, autoimmune hepatitis, primary biliary cirrhosis, primary sclerosing cholangitis, hemochromatosis, Wilson's disease, Gilbert's syndrome, fatty liver, non alcoholic steatohepatitis, alcoholic liver diseases, cardiac and thyroid causes, rhabdomyolysis, polymyositis, postictal state, tumors, lymphomas, chlamydial and HIV infections. Causality assessment methods applied in these 15 publications were the CIOMS (Council for International Organizations of Medical Sciences) scale alone (n = 5) or combined with the Maria and Victorino (MV) scale (n = 1), the DILIN (Drug-Induced Liver Injury Network) method (n = 4), or the Naranjo scale (n = 1); the qualitative CIOMS method alone (n = 3) or combined with the MV scale (n = 1). In conclusion, alternative diagnoses are common in primarily suspected DILI cases and should be excluded early in future cases, requiring a thorough clinical and causality assessment.
Introduction. This work focuses on ammonia metabolism of Liver Microorgans (LMOs) after cold preservation in a normothermic reoxygenation system (NRS). We have previously reported the development of a novel preservation solution, Bes-Gluconate-PEG 35 kDa (BG35) that showed the same efficacy as ViaSpan® to protect LMOs against cold preservation injury. The objective of this work was to study mRNA levels and activities of two key Urea Cycle enzymes, Carbamyl Phosphate Synthetase I (CPSI) and Ornithine Transcarbamylase (OTC), after preservation of LMOs in BG35 and ViaSpan® and the ability of these tissue slices to detoxify an ammonia overload in a NRS model. Material and methods. After 48 h of cold storage (0°C in BG35 or ViaSpan®) LMOs were rewarmed in KHR containing an ammonium chloride overload (1 mM). We determined ammonium detoxification capacity (ADC), urea synthesis and enzyme activities and relative mRNA levels for CPSI and OTC. Results. At the end of reoxygenation LMOs cold preserved in BG35 have ADC and urea synthesis similar to controls. ViaSpan® group demonstrated a lower capacity to detoxify ammonia and to synthesize urea than fresh LMOs during the whole reoxygenation period which correlated with the lower mRNA levels and activities for CPSI and OTC observed for this group. Conclusion. We demonstrate that our preservation conditions (48 hours, BG35 solution, anoxia, 0ºC) did not affect ammonia metabolism of cold preserved LMOs maintaining the physiological and biochemical liver functions tested, which allows their future use as biological component of a BAL system.
Introduction. Hepatorenal tyrosinemia (HT1) is a treatable, inherited, metabolic disease characterized by progressive liver failure with pronounced coagulopathy. The aim of this study is to describe the clinical, biochemical, and histopathological findings in a group of Mexican HT1 patients and their outcome. Material and methods. Medical records of HT1 patients diagnosed between 1995 and 2011 were analyzed. The diagnosis of HT1 was confirmed by detection of succinylacetone in urine or blood. Results. Sixteen nonrelated HT1 cases were analyzed. Mean age at clinical onset was 9 months, and the mean age at diagnosis was 16.3 months. Main clinical findings were hepatomegaly, splenomegaly, cirrhosis, liver failure, tubulopathy, nephromegaly, Fanconi syndrome, seizures and failure to thrive. Histopathological findings were cirrhosis, fibrosis and steatosis. The HT1 group had a mortality rate of 78%. Patients who received supportive care or nutritional treatment had a 3-year survival rate of 10%. For those who underwent liver transplantation, the 6-year survival rate was 60%. In most cases pharmacological treatment with nitisinone and special dietary products were not available. The leading causes of death were fulminant liver failure, metastatic hepatocellular carcinoma, and porphyria-like neurologic crisis. Newborn screening programs in combination with the availability of orphan drugs, proper monitoring, genetic counseling, and clinical practice guidelines are needed to enable physicians to identify the disease, delay its progression, and improve patients' quality of life. Conclusion. The devastating natural history of HT1 is still observed in Mexican patients because they are not diagnosed and treated during the early stages of the disease.
Spirulina platensis is a blue-green alga used as a dietary supplement because of its hypocholesterolemic properties. Among other bioactive substances, it is also rich in tetrapyrrolic compounds closely related to bilirubin molecule, a potent antioxidant and anti-proliferative agent. The aim of our study was to evaluate possible anticancer effects of S. platensis and S. platensis-derived tetrapyrroles using an experimental model of pancreatic cancer. The anti-proliferative effects of S. platensis and its tetrapyrrolic components [phycocyanobilin (PCB) and chlorophyllin, a surrogate molecule for chlorophyll A] were tested on several human pancreatic cancer cell lines and xenotransplanted nude mice. The effects of experimental therapeutics on mitochondrial reactive oxygen species (ROS) production and glutathione redox status were also evaluated. Compared to untreated cells, experimental therapeutics significantly decreased proliferation of human pancreatic cancer cell lines in vitro in a dose-dependent manner (from 0.16 g·L-1 [S. platensis], 60 μM [PCB], and 125 μM [chlorophyllin], p<0.05). The anti-proliferative effects of S. platensis were also shown in vivo, where inhibition of pancreatic cancer growth was evidenced since the third day of treatment (p < 0.05). All tested compounds decreased generation of mitochondrial ROS and glutathione redox status (p = 0.0006; 0.016; and 0.006 for S. platensis, PCB, and chlorophyllin, respectively). In conclusion, S. platensis and its tetrapyrrolic components substantially decreased the proliferation of experimental pancreatic cancer. These data support a chemopreventive role of this edible alga. Furthermore, it seems that dietary supplementation with this alga might enhance systemic pool of tetrapyrroles, known to be higher in subjects with Gilbert syndrome.
Severe liver dysfunction during pregnancy implies a serious risk for both mother and fetus, and represents a technical and ethical challenge for treating physicians. We report a case of a previously healthy 32-year old woman who was admitted to our hospital with idiopathic fulminant hepatic failure and underwent successful orthotopic liver transplantation (OLT) at gestation week 21. Patient's and fetus' immediate postoperative course were relatively uneventful until week six after OLT, when the mother developed oligohydramnios and preeclampsia. At pregnancy week 27, after inducing baby's lung maturation, a cesarean section was performed with the delivery of an otherwise healthy girl. After 3 years of follow-up, mother and child are leading normal lives with no complications related either to pregnancy or to OLT. We describe the case of a successful emergency liver transplant in a woman during the second trimester of pregnancy, demonstrating that OLT can be a viable option to preserve the life of the mother and an otherwise unviable fetus. Intrauterine baby's growths until the attainment of a viable gestational age was feasible despite the mother's fulminant hepatic failure and liver transplant surgery.
For the last decade, the combination therapy of pegylated interferon (Peg-IFN) plus ribavirin (RBV) has been considered as the standard of care treatment for chronic hepatitis C virus (HCV) infection. However, it has been associated with an increased incidence of many adverse cutaneous reactions and emergence of autoantibodies or even autoimmune diseases. We report a case of irreversible alopecia universalis (AU) with complete hair loss extended to the whole body, which started after discontinuation of Peg-IFN/RBV combination therapy for chronic HCV infection. In conclusion, this case represents an uncommon presentation of a common disease. Physicians must be aware of the potential adverse reactions of an antiviral therapy containing IFN, which might occur even after the discontinuation, and fully inform the patient at the beginning of his treatment course. We hope that interferon-free regimens will utterly supplant interferon- based therapy for most or all HCV patients avoiding the emergence of autoimmune manifestations.
In recent years, the use of diffusion weighted MRI (DW-MRI) has increased for the diagnosis of focal liver lesions (FLLs). DW-MRI may help in the differentiation of benign and malignant FLLs by measuring the apparent diffusion coefficient (ADC) values. Unfortunately, liver metastases present different histopathologic features with variable MRI signals within each lesion; this histologic variability explains the intra- and interlesion variations of ADC measurements. We present the case of a 64-year-old female with diagnosis of liver metastasis from small cell lung carcinoma admitted to the emergency unit due to symptoms of inappropriate antidiuretic hormone secretion. Quantitative comparison of two liver MRI, on admission and 2-months after transcatheter arterial chemoembolization showed persistence of the hyperintense metastatic lesions with significant difference in the ADC values in the with-in metastatic lesions (p = 0.001) and between normal tissue and liver metastases only at the end of treatment (p < 0.001). Several publications state that DWMRI is capable to predict the response to chemotherapy in malignant tumors, the histologic variability of liver metastasis and their response to different treatments is reflected in intra- and inter-lesion variations of ADC measurements that might delay an accurate imaging diagnosis. We present evidence of this variability, which might encourage prospective clinical trials that would define better cut-off values, would help understand the ADC biological behaviour, and would reach consensus about the best acquisition parameters for this promising quantitative biomarker.