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Nezam Afdhal

Publications and source records attributed to Nezam Afdhal.

14 recordsLinked to original sources
PubMed2006

Fibrosis as an end point for clinical trials in liver disease: a report of the international fibrosis group.

Deaths due to the consequences of advanced liver fibrosis and cirrhosis remain a significant cause of mortality worldwide. Biologically plausible pathways involved in hepatic fibrogenesis have also led to the identification of numerous preclinical and clinical compounds that have received great interest as potential future therapeutic agents for patients with liver fibrosis. With this in mind, stake holders from academia, regulatory agencies, clinicians, and the pharmaceutical industry met to understand and discuss the many complex issues involved in developing potential therapeutic agents which act primarily through modifying fibrosis and to discuss appropriate end points for clinical trials in these patient populations. In this article, we summarize those discussions and attempt to highlight many of the hurdles and unanswered questions as we attempt to move forward and develop therapies to combat liver fibrosis.

Animals↗
PubMed2006

Progression of liver fibrosis among injection drug users with chronic hepatitis C.

Although most hepatitis C virus (HCV) infections are acquired by injection drug use, prospective data on the progression of liver fibrosis are sparse. Baseline liver biopsies were obtained (1996-1998) on a random sample of 210 out of 1667 HCV-positive injection drug users (IDUs). Subjects were followed biannually, with a second biopsy offered to those eligible. Paired biopsies were scored 0 to 6 (modified Ishak score), significant fibrosis was defined as score 3 or greater, and progression of fibrosis was defined as an increase 2 or more units or clinical evidence of end-stage liver disease. Predictive values of blood markers [FibroSURE, aspartate aminotransferase-to-platelet-ratio index (APRI) and alanine aminotransferase (ALT)] were assessed for detection of contemporaneous and future liver fibrosis. Among 119 prospectively followed IDUs, 96% were African American; 97% HCV genotype 1a/b; 27% HIV-infected, and median age was 42 years. Most (90.7%) did not have significant liver fibrosis at first biopsy. Although predictive value for detecting insignificant fibrosis at first biopsy was greater than 95% for FibroSURE, APRI, and ALT, specificities were 88.9%, 72.7%, and 72.7%, respectively. After 4.2 years median follow-up, 21% had progression of fibrosis, which was significantly associated with serum level of HCV RNA and ALT. No serological test had predictive value greater than 40% for contemporaneous or future significant fibrosis. Even initial biopsy result had only a 30.4% value for predicting future significant fibrosis. In conclusion, significant liver fibrosis and progression were detected in some, but not most, IDUs in this cohort. In this setting with low fibrosis prevalence, FibroSURE, ALT, and APRI tests predict insignificant fibrosis; however, further work is needed to find noninvasive markers of significant liver fibrosis.

Adult↗
PubMed2006

Modeling hepatic fibrosis in African American and Caucasian American patients with chronic hepatitis C virus infection.

Assessment of histological stage is an integral part of disease management in patients infected with the hepatitis C virus (HCV). The aim of this study was to develop a model incorporating objective clinical and laboratory parameters to estimate the probability of severe fibrosis (i.e., Ishak fibrosis > or = 3) in previously untreated African American (AA) and Caucasian American (CA) patients with HCV genotype 1. The Ishak fibrosis scores of 205 CA and 194 AA patients enrolled in the Viral Resistance to Antiviral Therapy of Chronic Hepatitis C study (Virahep-C) were modeled using simple and multiple logistic regression. The model was then validated in an independent cohort of 461 previously untreated patients with HCV. The distribution of fibrosis scores was similar in the AA and CA patients as was the proportion of patients with severe fibrosis (35% vs. 39%, P = .47). After accounting for the number of portal areas in the biopsy, patient age, serum aspartate aminotransferase, alkaline phosphatase, and platelet count were independently associated with severe fibrosis in the overall cohort, and the relationship with fibrosis was similar in both the AA and CA subgroups. The area under the receiver operating characteristic curve (AUROC) of the Virahep-C model (0.837) was significantly better than in other published models (P = .0003). The AUROC of the Virahep-C model was 0.851 in the validation population. In conclusion, a model consisting of widely available clinical and laboratory features predicted severe hepatic fibrosis equally well in AA and CA patients with HCV genotype 1 and was superior to other published models. The excellent performance of the Virahep-C model in an external validation cohort suggests the findings are replicable and potentially generalizable.

Black or African American↗
PubMed2006

Peginterferon and ribavirin treatment in African American and Caucasian American patients with hepatitis C genotype 1.

BACKGROUND & AIMS: Compared with Caucasian Americans (CA), African Americans (AA) with chronic hepatitis C are less likely to respond to interferon-based antiviral therapy. METHODS: In a multicenter treatment trial, 196 AA and 205 CA treatment-naive patients with hepatitis C virus (HCV) genotype 1 infection were treated with peginterferon alfa-2a (180 microg/wk) and ribavirin (1000-1200 mg/day) for up to 48 weeks. The primary end point was sustained virologic response (SVR). RESULTS: Baseline features were similar among AA and CA, including HCV-RNA levels and histologic severity, but AA had higher body weights, a higher prevalence of diabetes and hypertension, and lower alanine transaminase levels (P < .001 for all). The SVR rate was 28% in AA and 52% in CA (P < .0001). Racial differences in viral responses were evident as early as treatment week 4. Breakthrough viremia was more frequent among AA than CA (13% vs 6%, P = .05); relapse rates were comparable (32% vs 25%, P = .30). Proportions of patients with serious adverse events and dose modifications and discontinuations were similar among AA and CA. In multiple regression analyses, CA had a higher SVR rate than AA (relative risk, 1.96; 95% confidence interval, 1.48-2.60; P < .0001). Other factors independently associated with higher SVR included female sex, lower baseline HCV-RNA level, less hepatic fibrosis, and more peginterferon taken. CONCLUSIONS: AA with chronic hepatitis C genotype 1 have lower rates of virologic response to peginterferon and ribavirin than CA. These differences are not explained by disease characteristics, baseline viral levels, or amount of medication taken.

Adolescent↗
PubMed2005

Assessment of liver fibrosis in co-infected patients.

The evaluation of liver injury in HIV patients co-infected with HBV and HCV should follow the same principles as the evaluation of any patient with chronic liver disease. The initial clinical evaluation should include documentation of risk factors for progressive disease. HIV history is important particularly with respect to a past history of significant or prolonged immunosuppression as this has been clinically correlated with more advanced liver disease. Liver transaminases are an important predictor of disease severity and progression in HIV patients. Liver biopsy has remained the 'gold standard' for the grading of inflammation and staging of disease. We would still recommend liver biopsy in HIV patients particularly those with HCV because recent community-based studies in the HAART era have suggested slower rates of progression for HIV/HCV than studies from tertiary care centres and older cohorts. Since, liver biopsy is invasive and expensive, non-invasive techniques including serological tests and novel imaging techniques have evolved to stage liver fibrosis. A novel technique for measuring hepatic elasticity has recently been validated alone and in combination with serum markers for HCV mono-infection. Future trends for staging liver disease must not only focus on cross sectional diagnosis but on utilizing novel techniques to stratify risk for disease progression over time.

Biopsy↗
PubMed2005

Maintenance therapy for chronic hepatitis C.

Major progress has been made in the treatment of chronic hepatitis C virus (HCV) infection over the 18 years since Hoofnagle et al. initially documented response of non-A non-B hepatitis to interferon alfa. Current optimal therapy with pegylated interferon alfa (PEG-IFN) and ribavirin results in sustained virologic response rates of just over 50%. With an estimated 2.7 million Americans with active HCV infection, we can anticipate a large number of potential treatment failures with the current standard of care. At this time, no therapy is approved by the US Food and Drug Administration for treatment failures of PEG-IFN and ribavirin. Maintenance interferon therapy with the goal of prevention of disease progression rather than viral eradication appears to offer an option for HCV treatment failures with advanced disease. Alternative medical strategies to reduce hepatic fibrosis are also under investigation. With the relatively static number of available organs for transplantation, prevention of disease progression and decompensation is essential for an impact to be made upon the predicted rates of HCV morbidity and mortality in the next 10 to 20 years.

Antiviral Agents↗
PubMed2005

Noninvasive assessment of liver fibrosis.

Understanding of the pathogenesis of hepatic fibrosis on a molecular level has led to the identification of several putative serum markers of hepatic fibrosis. Either individually or in combination, these serum markers appear capable of determining early and advanced hepatic fibrosis. Radiological determination of hepatic fibrosis has insufficient sensitivity and specificity other than for detection of features of portal hypertension or features of end-stage cirrhosis. Transient hepatic elastography is a novel technology demonstrating promise as a noninvasive means of fibrosis determination. This article outlines the accuracy of all these modalities in the diagnosis of hepatic fibrosis and discusses how they may be incorporated into clinical practice.

Biomarkers↗
PubMed2004

Hepatic CD1d expression in hepatitis C virus infection and recognition by resident proinflammatory CD1d-reactive T cells.

A subset of CD161(+)CD56(+/-) NKT cells can recognize glycolipids presented by CD1d and positively or negatively regulate inflammatory responses, including those implicated in several models of hepatitis. CD1d is expressed at very low levels in the healthy liver, but there is a large fraction of CD161(+)CD56(+) NKT cells. There are high levels of nonclassical proinflammatory hepatic CD1d-reactive T cells in hepatitis C virus (HCV) infection. Hepatic inflammatory cells and biliary cells adjacent to portal tract fibrotic areas of HCV-infected donors specifically up-regulated CD1d. A hepatocyte cell line expressing minimal CD1d was efficiently recognized by hepatic CD1d-reactive T cells, suggesting a role for these cells in disease. Hepatic CD1d-reactive T cells from HCV-positive as well as negative donors produced large amounts of IFN-gamma with some IL-13, but only rarely detectable IL-4. We confirmed large numbers of hepatic CD161(+) T cells, lower levels of CD56(+) T cells, and small numbers of classic invariant NKT cells. However, hepatic CD1d-reactivity was not restricted to any of these populations. We suggest virally infected hepatic cells can process potent CD1d-presented liver Ag(s), for surveillance by resident Th1 hepatic CD1d-reactive T cells. This process may be beneficial in acute viral clearance, but in chronic infection could contribute to liver injury.

Acute Disease↗
PubMed2004

Comparison of HCV-specific intrahepatic CD4+ T cells in HIV/HCV versus HCV.

Persons with human immunodeficiency virus (HIV) and hepatitis C virus (HCV) coinfection are at increased risk for progression to cirrhosis compared with persons with HCV alone, but the reasons for this are unclear. In chronic HCV, the mechanism of liver injury is presumed to be due to HCV-specific T cell destruction of hepatocytes, so it is paradoxical that immunosuppressed hosts have higher rates of fibrosis progression. We examined intrahepatic cellular immune responses to HCV antigens to determine whether there were qualitative or quantitative differences in subjects with and without HIV. Expanded, CD4-enriched, liver-infiltrating lymphocytes from 18 subjects with chronic HCV and 12 subjects with HIV/HCV were cultured in the presence of HCV core protein, nonstructural proteins NS3 and NS5, and recall antigens tetanus toxoid and Candida. Secretion of interferon gamma (IFN-gamma), tumor necrosis factor alpha (TNF-alpha), and interleukin (IL) 10 was determined using enzyme-linked immunosorbent spot assay. There were no significant differences in liver biopsy grade or stage for HIV/HCV versus HCV groups. There were no significant differences between groups in the secretion of IFN-gamma or TNF-alpha in response to HCV or recall antigens. However, there was a significant increase in IL-10 secretion in response to NS3 and NS5 in subjects with HCV compared with HIV and HCV coinfection. In conclusion, subjects with coinfection have an alteration of intrahepatic HCV-specific IL-10 cytokine response that may have implications for HCV-related disease progression.

Acquired Immunodeficiency Syndrome↗
PubMed2003

Integrin alpha1beta1 and alpha2beta1 are the key regulators of hepatocarcinoma cell invasion across the fibrotic matrix microenvironment.

As with many types of cancer, cell motility is an important factor in the progression and metastasis of hepatocellular carcinomas (HCC). HCC is associated with significant fibrosis in the liver. The fibrotic microenvironment in the liver is characterized by an altered composition of the extracellular matrix (ECM) and an abundance of growth factors that are likely conducive to migration of HCC cells. The purpose of this study was to delineate promigratory stimuli within the fibrotic microenvironment and to identify specific targets for prevention of HCC cell migration. We used a modified Boyden chamber system that allowed distinction between chemotactic (indirect stimulation) and haptotactic (direct stimulation) migration of two distinct HCC cell lines across the ECM-coated membrane. Fibrotic microenvironment-associated growth factors, such as transforming growth factor beta1 (TGF-beta1), basic fibroblast growth factor (bFGF), and epidermal growth factor (EGF), induced chemotactic and haptotactic migration of HepG2 and Chang cells. Neutralizing antibodies to individual growth factors significantly decreased chemotactic and haptotactic migration. Haptotactic stimulation, but not chemotactic stimulation of HCC cell lines with TGF-beta1, bFGF, and EGF, induced production of matrix metalloproteinase (MMP) 2, a potential mediator of migration. Inhibition of MMPs significantly decreased haptotactic migration induced by individual growth factors but had an insignificant effect on chemotactic migration, suggesting an MMP-independent migration in this setting. Inhibition of cell-ECM interactions with blocking antibodies to alpha1 and alpha2 integrins were sufficient to inhibit both haptotactic and chemotactic migration induced by individual growth factors, strongly suggesting that targeting these integrins to abrogate pathogenic cell-ECM interactions might be a promising tool for inhibiting growth factor-induced invasion and metastasis of HCC.

Carcinoma, Hepatocellular↗
PubMed2003

Liver fibrosis: insights into migration of hepatic stellate cells in response to extracellular matrix and growth factors.

BACKGROUND & AIMS: In liver fibrosis, alterations within the space of Disse microenvironment occur and facilitate further progression of chronic liver disease. The normal basement membrane-like matrix present within the space of Disse converts to a matrix rich in fibril-forming collagens during fibrosis. METHODS: To further understand the pathogenesis of liver fibrosis, we modified an in vitro Boyden chamber system to partially mimic in vivo conditions of hepatic stellate cells (HSCs) during health and disease. RESULTS: Stimulation of HSCs with platelet-derived growth factor (PDGF)-BB, transforming growth factor (TGF)-beta1, and/or epithelial growth factor (EGF) resulted in an increase in their migratory capacity and up-regulated matrix metalloproteinase (MMP)-2 activity. Migration induced by PDGF-BB was associated with increased proliferation, whereas TGF-beta1/EGF-induced migration was proliferation independent. COL-3, an inhibitor of MMP-2 and MMP-9, inhibited migration of HSCs induced by direct activation of PDGF-BB or TGF-beta1 but had no effect on migration induced by chemotactic stimuli without direct contact, suggesting 2 distinct MMP-dependent and MMP-independent mechanisms of PDGF-BB- or TGF-beta1-induced migration. Additionally, we show that type I collagen by itself induced migration of HSCs. Migration induced by PDGF-BB, TGF-beta1, and collagen I could be inhibited by alpha(1)- and/or alpha(2)-integrin blocking antibodies, collectively suggesting an integrin-dependent, MMP-2-mediated migration of HSCs. CONCLUSIONS: Basement membrane matrix integrity, composition, and cell-matrix interactions play an important role in anchoring HSCs and preventing them from spreading within the space of Disse and potentially elsewhere in the liver. Additionally, our data provide strong evidence for MMPs in regulation of HSCs migration.

Animals↗
PubMed2002

Cholangiocarcinoma of the Hepatic Hilum (Klatskin Tumor).

Since the description by Klatskin in 1965, the management of patients with adenocarcinoma of the hepatic bile duct bifurcation is viewed as a challenging clinical problem with a relatively poor prognosis. Surgery continues to be the mainstay of therapy. Complete resection of the tumor with negative histologic margins offers the best possibility of long-term survival, and hepatic resection is a critical component of the operative approach. Adjuvant chemoradiotherapy has failed to provide a significant survival benefit. Orthotopic liver transplantation for otherwise unresectable lesions remains controversial, as tumor recurrence has been reported in more than 90% of patients. With the shortage of organs, such patients to be selected carefully for transplanation. For patients who present with widespread disease and those with high operative risks, advances in interventional radiology and endoscopy have facilitated nonsurgical management options. Biliary decompression using expandable metallic stents provides superior patency and decreased frequency of hospitalization when compared with plastic stents. Moreover, patients treated with expandable metal stents have survival rates comparable with those who undergo surgical decompression, with fewer early complications. The benefit of external beam radiotherapy for palliation of proximal cholangiocarcinoma is uncertain. Radiotherapy in conjunction with biliary stenting has a survival benefit over stenting alone, but is not without potential toxicity. It should be considered as an adjunct to biliary decompression in all patients with good performance status, because modern conformal CT-based dosimetry can minimize toxicity to normal adjacent tissue. Photodynamic therapy is emerging as a new palliative treatment modality for patients with unresectable tumors in whom stenting has failed. It offers the advantage of an endoscopic delivery system, and unlike radiotherapy, photodynamic therapy may be delivered repeatedly.

Journal Article↗
PubMedDate not supplied

Symptomatic focal nodular hyperplasia during pregnancy: a case report.

A 30-year-old woman presented with hepatomegaly and an audible hepatic bruit at 24 weeks gestation. Non-contrast MRI demonstrated an exophytic 12.6 x 7.8 x 12.8 cm mass arising from the right lobe of the liver with a central scar, suggestive of focal nodular hyperplasia (FNH). Conservative management included monthly abdominal ultrasound examinations until the time of delivery, to assess growth of the mass and monitor for risk of rupture. Seven weeks post partum the patient experienced severe right upper quadrant pain. A CT angiogram of the liver demonstrated a stable mass with no evidence of bleed or rupture and multiple hypervascular masses throughout the liver. Surgical resection of the dominant lesion was performed. Histological examination of the lesion confirmed FNH. The patient is now 22 months post surgery with radiographic evidence of stable multifocal FNH.

Abdominal Pain↗