Brian B. Borg

The effects of discontinuing pioglitazone in patients with nonalcoholic steatohepatitis

A pilot study of a 48‐week course of pioglitazone demonstrated significant improvements in the biochemical and histological features of nonalcoholic steatohepatitis (NASH). The aim of the study was to assess the effects of stopping pioglitazone. Twenty‐one patients with NASH were treated with pioglitazone (30 mg/day) for 48 weeks and underwent baseline and end‐of‐treatment evaluation including liver biopsy. Thirteen patients were followed for at least 48 weeks after stopping therapy and 9 underwent repeat liver biopsy. Statistical comparisons were made to evaluate whether discontinuation of pioglitazone resulted in a reversal of improvements seen on therapy. Stopping pioglitazone was associated with subsequent elevation in serum alanine aminotransferase levels (from 34 ± 13 to 70 ± 39 IU/l), decrease in adiponectin (from 9.7 ± 9.1 to 5.1 ± 4.5 μg/ml), worsening insulin sensitivity (HOMA Index: from 2.9 ± 1.8 to 5.5 ± 5.4), and increase in total hepatic fat (from 30% ± 32% to 71% ± 33%) despite no change in average body weight compared to the end of treatment. Repeat liver biopsy in 9 patients revealed significant worsening of parenchymal inflammation (from 1.2 ± 0.7 to 2.9 ± 1.1) and steatosis (from 0.9 ± 0.6 to 2.1 ± 1.3) but no change in fibrosis (from 1.1 ± 1.2 to 1.2 ± 1.3). NASH was again present on liver biopsy in 7 patients. Conclusion: These findings suggest that long‐term therapy with pioglitazone may be necessary to maintain improvements in disease activity in patients with NASH, although weight gain during treatment may ultimately limit its beneficial effects. (HEPATOLOGY 2007.)

Clinical trial: pilot study of metformin for the treatment of non-alcoholic steatohepatitis

Background  Non‐alcoholic steatohepatitis (NASH) is a form of progressive fatty liver disease that is strongly associated with insulin resistance, which suggests that insulin sensitizing agents such as metformin may be beneficial for NASH.

Immunization with hepatitis C virus-like particles results in control of hepatitis C virus infection in chimpanzees

Recombinant hepatitis C virus (HCV)-like particles (HCV-LPs) containing HCV structural proteins (core, E1, and E2) produced in insect cells resemble the putative HCV virions and are capable of inducing strong and broad humoral and cellular immune responses in mice and baboons. Here, we present evidence on the immunogenicity and induction of protective immunity by HCV-LPs in chimpanzees. Chimpanzees (two in each group), were immunized with HCV-LPs or HCV-LPs plus AS01B adjuvant. After immunizations, all animals developed an HCV-specific immune response including IFN-γ+, IL-2+, CD4+, and CD8+ T cell and proliferative lymphocyte responses against core, E1, and E2. Upon challenge with an infectious HCV inoculum, one chimpanzee developed transient viremia with low HCV RNA titers (103 to 104 copies per ml) in the third and fourth weeks after the challenge. The three other chimpanzees became infected with higher levels of viremia (104 to 105 copies per ml), but their viral levels became unquantifiable (<103 copies per ml) 10 weeks after the challenge. After the HCV challenge, all four chimpanzees demonstrated a significant increase in peripheral and intrahepatic T cell and proliferative responses against the HCV structural proteins. These T cell responses coincided with the fall in HCV RNA levels. Four naïve chimpanzees were infected with the same HCV inoculum, and three developed persistent infection with higher viremia in the range of 105 to 106 copies per ml. Our study suggests that HCV-LP immunization induces HCV-specific cellular immune responses that can control HCV challenge in the chimpanzee model.

A functional SNP of interferon-γ gene is important for interferon-α-induced and spontaneous recovery from hepatitis C virus infection

Cytokine polymorphisms are associated with disease outcome and interferon (IFN) treatment response in hepatitis C virus (HCV) infection. We genotyped eight SNPs spanning the entire IFN-γ gene in two cohorts and assessed the association between those polymorphisms and treatment response or spontaneous viral clearance. The first cohort was composed of 284 chronically HCV-infected patients who had received IFN-α-based therapy and the second was 251 i.v. drug users who had either spontaneously cleared HCV or become chronically infected. A SNP variant located in the proximal IFN-γ promoter region next to the binding motif of heat shock transcription factor (HSF), −764G, was significantly associated with sustained virological response [P = 0.04, odds ratio (OR) = 3.51 (confidence interval 1.0–12.5)]. The association was independently significant in multiple logistic regression (P = 0.04) along with race, viral titer, and genotype. This variant was also significantly associated with spontaneous recovery [P = 0.04, OR = 3.51 (1.0–12.5)] in the second cohort. Functional analyses show that the G allele confers a two- to three-fold higher promoter activity and stronger binding affinity to HSF1 than the C allele. Our study suggests that the IFN-γ promoter SNP −764G/C is functionally important in determining viral clearance and treatment response in HCV-infected patients and may be used as a genetic marker to predict sustained virological response in HCV-infected patients.

Impact of Obesity on Bowel Preparation for Colonoscopy

BACKGROUND & AIMS An inadequately cleansed colon can lead to missed lesions, repeat procedures, increased cost, and complications from colonoscopy. Because obesity, with its known link to colorectal neoplasia, might be associated with inadequate bowel cleansing, we investigated the impact of increased body mass index (BMI) on quality of bowel preparation at colonoscopy. METHODS All colonoscopy procedures performed at a tertiary referral center during a 4-month period were evaluated. Bowel preparation was assigned a unique composite outcome score that took into account a subjective bowel preparation score, earlier recommendation for follow-up colonoscopy as a result of inadequate bowel preparation, and the endoscopists confidence in adequate evaluation of the colon. Univariate and multivariate logistic regression analyses were performed to identify the role of BMI in predicting an inadequate bowel preparation. RESULTS During the study period, 1588 patients (59.1% female; mean age, 57.4 +/- 0.34 years) fulfilled inclusion criteria. An abnormal BMI (> or =25) was associated with an inadequate composite outcome score (P = .002). In multivariate logistic regression analyses, both BMI > or =25 (P = .04) and > or =30 (P = .006) were retained as independent predictors of inadequate bowel preparation. Each unit increase in BMI increased the likelihood of an inadequate composite outcome score by 2.1%. Additional independent predictors of inadequate preparation exponentially increased the likelihood of an inadequate composite outcome score; 7 additional risk factors identified 97.5% of overweight patients with an inadequate composite outcome score. CONCLUSIONS Obesity is an independent predictor of inadequate bowel preparation at colonoscopy. The presence of additional risk factors further increases the likelihood of a poorly cleansed colon.

Steatosis and progression of fibrosis in untreated patients with chronic hepatitis C infection.

Hepatic steatosis is common in patients with chronic hepatitis C (CHC) and is reported to be a risk factor for progression of fibrosis. The aims of this study were to evaluate the interactions between hepatic steatosis and fibrosis in a well‐defined cohort of patients with CHC. The computerized pathology database at the National Institutes of Health Clinical Center was searched for patients with CHC who had undergone liver biopsy between 1980 and 2003. Biopsies were scored for necroinflammation using a modified histology activity index, fibrosis using the Ishak system, and steatosis as either none (<5% of cells), mild (5%–25%), or moderate‐to‐severe (>25%). Four hundred ninety‐four patients were identified. The mean age was 44 ± 9.8 years; 60% were male, 80% Caucasian, and 65% were infected with genotype 1. Steatosis was mild in 31% and moderate to severe in 9% of patients. In univariate analysis, steatosis was associated with increased age, body weight, body mass index (BMI), alanine aminotransferase (ALT) levels, histological necroinflammatory activity, and fibrosis. However, in multivariate analysis, steatosis was associated only with increased age, BMI, and ALT levels and not with fibrosis. One hundred thirty‐six patients had 2 liver biopsies separated by 0.5 to 17 years. Worsening of fibrosis occurred in 40% of patients and correlated independently with increasing age, periportal necroinflammation, and ALT elevations but not with steatosis. In conclusion, in this cohort of patients with CHC, steatosis was associated with older age, higher BMI, and higher serum ALT levels but not with the presence of or subsequent progression of fibrosis. (HEPATOLOGY 2006;43:780–787.)

Reactivation of hepatitis B with reappearance of hepatitis B surface antigen after chemotherapy and immunosuppression.

BACKGROUND & AIMS HBV infection may reactivate in the setting of immunosuppression, although the frequency and consequences of HBV reactivation are not well known. We report 6 patients who experienced loss of serologic markers of hepatitis B immunity and reappearance of HBsAg in the serum as a result of a variety of acquired immune deficiencies. METHODS Between 2000 and 2005, six patients with reactivation of hepatitis B were seen in consultation by the Liver Diseases Branch at the Clinical Center, National Institutes of Health. The course and outcome of these 6 patients were reviewed. RESULTS All 6 patients developed reappearance of HBsAg and evidence of active liver disease after stem cell transplantation (n = 4), immunosuppressive therapy (n = 1), or change in human immunodeficiency virus antiretroviral regimen (n = 1), despite having antibody to HBsAg (anti-HBs) or antibody to hepatitis B core antigen (anti-HBc) without HBsAg before. All 6 patients developed chronic hepatitis B, 2 patients transmitted hepatitis B to their spouses, and 1 patient developed cirrhosis. The diagnosis of hepatitis B reactivation was frequently missed or delayed and often required interruption of the therapy for the underlying condition. None of the patients received antiviral prophylaxis against HBV reactivation. CONCLUSIONS Serologic evidence of recovery from hepatitis B infection does not preclude its reactivation after immunosuppression. Screening for serologic evidence of hepatitis B and prophylaxis of those with positive results by using nucleoside analogue antiviral therapy should be provided to individuals in whom immunosuppressive therapy is planned.

Queue Position in the Endoscopic Schedule Impacts Effectiveness of Colonoscopy

OBJECTIVES:Endoscopist fatigue potentially impacts colonoscopy. Fatigue is difficult to quantitate, but polyp detection rates between non-fatigued and fatigued time periods could represent a surrogate marker. We assessed whether timing variables impacted polyp detection rates at a busy tertiary care endoscopy suite.METHODS:Consecutive patients undergoing colonoscopy were retrospectively identified. Indications, clinical demographics, pre-procedural, and procedural variables were extracted from chart review; colonoscopy findings were determined from the procedure reports. Three separate timing variables were assessed as surrogate markers for endoscopist fatigue: morning vs. afternoon procedures, start times throughout the day, and queue position, a unique variable that takes into account the number of procedures performed before the colonoscopy of interest. Univariate and multivariate analyses were performed to determine whether timing variables and other clinical, pre-procedural, and procedural variables predicted polyp detection.RESULTS:During the 4-month study period, 1,083 outpatient colonoscopy procedures (57.5±0.5 years, 59.5% female) were identified, performed by 28 endoscopists (mean 38.7 procedures/endoscopist), with a mean polyp detection rate of 0.851/colonoscopy. At least, one adenoma was detected in 297 procedures (27.4%). A 12.4% reduction in mean detected polyps was detected between morning and afternoon procedures (0.90±0.06 vs. 0.76±0.06, P=0.15). Using start time on a continuous scale, however, each elapsed hour in the day was associated with a 4.6% reduction in polyp detection (P=0.005). When queue position was assessed, a 5.4% reduction in polyp detection was noted with each increase in queue position (P=0.016). These results remained significant when controlled for each individual endoscopist.CONCLUSIONS:Polyp detection rates decline as time passes during an endoscopists schedule, potentially from endoscopist fatigue. Queue position may be a novel surrogate measure for operator fatigue.

Interleukin-6 haplotypes and the response to therapy of chronic hepatitis C virus infection.

Chronic hepatitis C virus (HCV) infection affects nearly 170 million individuals worldwide. Treatment of HCV with pegylated interferon-α-2a is successful in eradicating virus from only 30 to 80% of those treated. Interleukin-6 (IL-6) is an important cytokine involved in the immune response to infectious agents and in vitro studies suggest that host genetic variation, particularly haplotypes, may affect IL-6 expression. We examined the contribution of haplotypes in the IL-6 gene on sustained viral response (SVR) to the therapy for chronic HCV infection. We observed the IL-6 T-T-G-G-G-G-C-A-G-A haplotype to be associated with a lower risk of achieving SVR among Caucasian Americans (CAs) ((relative risk) RR=0.80; 95% CI: 0.66−0.98; P=0.0261). Using a sliding window approach, the rs1800797-(G)-rs1800796-(G)-rs1800795-(G) haplotype was associated with a reduced chance of SVR (RR=0.79; 95% CI: 0.66–0.94; P=0.0081), as was the rs1800796-(G)-rs1800795-(G)-rs2069830-(C) haplotype (RR=0.78; 95% CI: 0.66–0.94; P=0.0065) among CAs. Overall, the rs1800797-(G)-rs1800796-(G)-rs1800795-(G) haplotype was independently associated with a reduced chance of SVR (RR=0.78; 95% CI: 0.62–1.0; P=0.0489) after adjustment for potential confounding factors. Our findings further illustrate the complexity of IL-6 genetic regulation and the potential importance of haplotypes on IL-6 expression. Our findings provide additional support for the potential importance of genetic variation in the IL-6 gene and the response to HCV therapy.

Immune response to extracellular matrix collagen in chronic hepatitis C–induced liver fibrosis

Hepatitis C virus (HCV) infection and its recurrence after orthotopic liver transplantation (OLT) are associated with the remodeling of extracellular matrix (ECM) components [particularly collagen (Col)], which leads to fibrosis. Our aim was to determine whether the development of antibodies (Abs) to self‐antigen Col in HCV‐infected patients correlates with the fibrosis stage and the peripheral cytokine response. Patients with chronic HCV infection, patients with HCV recurrence after OLT who had undergone a biopsy procedure, and healthy control subjects were enrolled. The HCV subjects (n = 70) were stratified as follows: (1) a non‐OLT group without fibrosis (Scheuer stages 0‐2), (2) a non‐OLT group with fibrosis (Scheuer stages 3‐4), (3) a post‐OLT group without fibrosis (Scheuer stages 0‐2), and (4) a post‐OLT group with fibrosis (Scheuer stages 3‐4). Serum samples were analyzed for Abs against Col1, Col2, Col4, Col5, and vimentin with enzyme‐linked immunosorbent assays. Serum levels of cytokines were measured with multiplex bead immunoassays. The levels of Abs to Col1 were higher in the fibrosis groups versus the no‐fibrosis groups and the controls for both non‐OLT patients (P < 0.001) and post‐OLT patients (P = 0.01). There were increased levels of Abs to Col2, Col4, Col5, and vimentin in the non‐OLT fibrosis group (Col2, P = 0.0001; Col4, P = 0.122; Col5, P < 0.0001; vimentin, P = 0.36) and in the post‐OLT fibrosis group (Col2, P = 0.006; Col4, P = 0.19; Col5, P < 0.0001; vimentin, P = 0.24) in comparison with the no‐fibrosis groups. The non‐OLT and post‐OLT fibrosis groups demonstrated significantly higher T helper 2 (Th2) and T helper 17 (Th17) cytokine levels and lower T helper 1 cytokine levels in comparison with the no‐fibrosis groups. Our results demonstrate that in HCV‐infected patients, the levels of Abs to ECM Col1, Col2, and Col5 positively correlate with liver fibrosis, which is associated with a predominantly Th2 and Th17 cytokine profile. Liver Transpl 17:814‐823, 2011.