S2074 Failure of Liver Stiffness Measurement Using Transient Elastography (FibroScan®) - Predictor Factors

did not have any risk factors for acute HBV, suggesting HBV reactivation (median viral load: 7.2 log copies); 8/14 (57%) were of Asian descent, median age: 46 years. Chemotherapy was administered a median of 21 days (range 8-141 days) prior to reactivation. Underlying diagnoses included: 5 lymphomas, 2 hepatocellular carcinomas, 2 glioblastomas, 1 leukemia, 1 esophageal CA, 1 sarcoma, 1 breast CA, and 1 jejunal CA. Multiple different chemotherapeutic agents were administered; 2 developed reactivation with high dose steroids alone. Two patients required transfer to a transplant center for fulminant liver failure; 3 patients ultimately died from liver failure. Thirteen patients (93%) required hospitalization; median length of stay: 5 days (range 2-33 days). Four patients experienced clinically significant delays in treatment due to HBV reactivation. Patients with lymphoma at our institution have had pre-treatment evaluation of hepatitis serologies with antiviral prophylaxis for HBV carriers since 2006, when a protocol for this was initiated. Since then, there has been only 1 reactivation of HBV on the lymphoma service. Conclusions: Reactivation of HBV after chemotherapy or steroid administration can occur in patients of various ethnicities, without association with a particular malignancy or medication. Reactivation resulted in significant hospitalizations, as well as delays in cancer treatments; 3 patients died from liver failure in a 5 year period. Antiviral prophylaxis for HBV may be effective in preventing reactivation; prospective studies are needed to identify the optimal timing, duration and type of prophylaxis. S2076 Antiviral Resistance in Patients with Chronic Hepatitis B Arathi Rajendra, Arkady Broder, Priyanka Mittar, Patricia Friedmann, Denis Kapkov, David J. Clain, Henry C. Bodenheimer, Albert D. Min Nucleos(t)ide analogues for treatment of chronic hepatitis B virus (HBV) infection have excellent safety profiles, but have potential limitations for long-term management of patients with antiviral resistance. Our aim was to identify factors associated with the occurrence of antiviral resistance. Methods: We reviewed the charts of 300 consecutive patients with chronic hepatitis B seen between 2000 and 2008. Data regarding age, ethnicity, mode of transmission, serial labs (HBeAg, HBV DNA, anti-HBe), and antiviral agents used were collected after excluding those with HIV, HCV, or liver transplant. Patients defined as having antiviral resistance were LAM-refractory (previously treated with LAM for >1 year but persistent HBV DNA>100,000 copies/mL), had virologic breakthrough (VB) (serum HBV DNA> 1 log10 above nadir) and/or had genotypic resistance (GR) (presence of polymerase genetic mutations on antiviral treatment) and were analyzed separately. Statistical analysis was performed using chi-square and Fisher's exact tests and multivariate logistic regression. Results: 201 patients (76% male, mean age 44 +/- 13, 69% Asian) with chronic hepatitis B being treated with antiviral agents were identified. 61 patients were LAM-refractory, 39 had VB, and 18 had GR. Multivariate predictors of having any type of resistance (LAM-refractory, VB, and/or GR) were having acquired HBV through vertical transmission (adjusted OR (AOR)=2.1, 95% CI 1.0-4.1), receiving LAM for > 3 years(AOR=16.5, 95% CI 3.5-77.2), and being HBeAg-positive(AOR=2.1, 95% CI 1.1-3.9). Multivariate predictors of being LAMrefractory were having acquired HBV through vertical transmission (AOR=4.0: 95% CI 1.79.7) and receiving LAM for > 3 years (AOR=30.4: 95% CI 6.3-147.2). Adefovir resistance (A181T/V and/or N236T) occurred in 5% (6/118) of patients with antiviral resistance. In the LAM-refractory group, the following treatment regimens were given: adefovir 39%, entecavir 12%, tenofovir 10%, LAM and adefovir 12%, LAM and tenofovir 3%, entecavir and adefovir 8%, entecavir and tenofovir 3%, tenofovir and telbivudine 2%, telbivudine and adefovir 2%, emtricitabine and tenofovir 3%, and unknown 6%. At present, 61% are on monotherapy and 39% are on combination therapy. Conclusions: Those HBV patients who were LAM-refractory were more likely to have acquired HBV through vertical transmission and received LAM for > 3 years. Despite a recent trend towards “add-on” therapies in patients with antiviral resistance, a significant proportion of patients remain on sequential monotherapy suggesting a need for standardized ways of preventing and optimizing anitiviral resistance management.

S2074 Failure of Liver Stiffness Measurement Using Transient Elastography (FibroScan®) - Predictor Factors Roxana Sirli, Ioan Sporea, Alexandra E. Deleanu, Adriana Tudora, Simona I. Bota, Alina Popescu, Mirela Danila Objective: Liver stiffness measurement (LSM) using transient elastography (FibroScan® device) is a novel rapid, non-invasive technique that evaluates liver fibrosis. In some cases, however, no elasticity measurement is obtained. The aim of this study was to assess the prevalence and factors associated with failure of LSM in patients with chronic liver disease. Material and methods: Our study included 2609 successive patients with chronic liver disease of diverse etiologies. Failure was defined if 10 valid measurements (VM) could not be obtained. We analyzed the factors that influence failure rate. We divided our group in under weight (BMI≤18.5 kg/m2), normal weight (BMI 17-24.9 kg/m2), overweight (BMI 25-29.9 kg/m2), class I obesity (BMI 30-34.9 kg/m2), class II obesity (BMI 35-39.9 kg/m2), class III obesity (BMI ≥40kg/m2). Results: From the 2609 patients, failure to obtain a VM was observed in 6.1% (160) of the cases. The mean body mass index (BMI) in the failure group was 30.8±5.7 kg/m2, extremely significant higher than in the VM group (26.1±4.2 kg/m2) (p<0.0001). The influence of BMI on the failure rate of LSM is presented in table I. The proportion of failure among women was significantly higher - 8.2% (103/1262), than in men -4.2% (57/1347) (OR=1.848, 95%CI: 1.324-2.58, p=0.0003). The mean age in the failure group was 55.4±11.7, extremely significantly higher than in the VM group (50.6±14.1) (p<0.0001). Conclusions: Failure to obtain valid LSM was observed in 6.1% of the patients. Female gender, older age and higher BMI were statistically significant associated with failure to obtain valid LSM. The failure rate increases with BMI, double in overweight patients as compared to normal weight ones (4.2% vs. 2.0%, OR 2.12), reaching 45% in class III obese patients, as compared to 2.0% in normal weight ones (OR 39.48). Table I

S2077 Are High Risk Individuals Appropriately Screened for Hepatitis B Virus (HBV) Infection? a Survey of Physician Knowledge, Attitudes and Beliefs About CDC Guidelines Temitope Foster, Fasiha Kanwal, Steven-Huy B. Han, Brennan M. Spiegel Background: The overall incidence of HBV has steadily declined since the introduction of universal vaccine guidelines, yet there has not been a concomitant drop in men >19 & women >40 years. The CDC responded in 2006 by expanding universal vaccine guidelines to include people with >2 sexual partners/year, men who have sex with men, and IV drug users. Despite highly effective vaccines and widely publicized guidelines, the incidence of HBV in high risk groups remains unnecessarily elevated, suggesting underuse of vaccines. We conducted a national survey to measure practice patterns of HBV vaccination, and to identify predictors of vaccination underuse. Methods: We created a survey with 4 clinical vignettes, each describing a patient at high risk for contracting HBV, per CDC guidelines. Vignettes were followed by questions regarding knowledge, attitudes, & beliefs (KAB) of HBV screening/vaccination. Respondents rated the appropriateness of HBV screening in each patient using a standard 9-point RAND Appropriateness Scale (RAS) (1-3=inappropriate, 46=unsure, 7-9=appropriate). We calculated a composite “HBV vaccination index” by summing the 4 RAS items (max=36 pts; higher score=higher guideline compliance), and performed multivariable regression to identify specific KAB profiles that predict scores. We surveyed a random sample of 930 physicians, including internists, family medicine, OB/GYN and GI/ Hepatologist, along with 50 experts in HBV epidemiology. Results: 15% responded (N= 144; 15 experts). Respondents correctly endorsed 74% of CDC-supported actions, on average. The mean vaccination index was 29+5. In stepwise regression, we identified 4 KAB predictors of diminished screening proclivity, categorized by KAB: (1) stronger belief that a sexual history is not an important part of a new visit [Belief]; (2) lower willingness to take a history of condom frequency [Attitude]; (3) stronger belief that HBV is not a prominent public health problem [Belief]; & (4) lower awareness that adult HBV in is contracted primarily through heterosexual sex [Knowledge]. Adherence was also lower in younger respondents.

S2075 Reactivation of Hepatitis B Viral Infection in Association with Chemotherapeutic and Immunosuppressive Agents: 5 Year Experience At a Single Cancer Center Satish Nagula, Emmy Ludwig Background: Reactivation of hepatitis B viral infection (HBV) following immunosuppression from chemotherapeutic agents can cause significant morbidity and mortality. This has been best documented in patients receiving chemotherapy for lymphoma; most reports have been in Asian populations. The incidence and ramifications of reactivation in a heterogenous group of cancer patients is unknown. Methods: We performed a retrospective review of all patients with a malignancy at Memorial Sloan-Kettering Cancer Center who had an HBV PCR >1000 copies between 2003 and 2008 associated with an acute increase in serum aminotransferase values. The medical record was used to distinguish between reactivation of latent HBV or de novo infections. Patient demographics, type of malignancy, timing and type of chemotherapy or immunosuppressive agent, and clinical outcome were recorded. Results: We identified 168 patients with an HBV PCR >1000 copies, of which 15 patients had an associated acute elevation in serum aminotransferases. Fourteen of these patients

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if it included at least 8 portal tracts and very good if it included at least 11 portal tracts. The LS was measured by means of FibroScan (EchoSens, France). We evaluated the correlation and predictive value of LS for fibrosis, according to the quality of liver sample. Results: According to the Metavir scoring system, from the 166 patients, 2 had no fibrosis (F0), 8 had mild fibrosis (F1), 69 had moderate fibrosis (F2), 37 had severe fibrosis (F3) and 22 had cirrhosis (F4). The correlations between LS measurements and fibrosis, as well as the predictive value of LS for significant fibrosis (F≥2 Metavir), according to the quality of liver sample, are presented in table 1: For an optimized cut-off value of 6.8 kPa, the predictive values of LSM for significant fibrosis were similar: AUROC 0.769 in patients in which liver samples that included at least 11 portal tracts, with 54.5% Se and 100% Sp; AUROC 0.736 in the subgroup of patients with liver samples at least 2.5 cm, with 53.9% Se and 90% Sp (p=0.7259); and AUROC 0.723 in the whole group, with 53.2% Se and 91.7% Sp (p= 0.6508). Conclusions: The correlation between the liver stiffness measured by FibroScan and fibrosis in patients with chronic C hepatitis is influenced by the quality of the liver sample. If the liver specimen included less than 11 portal tracts, the liver stiffness was not correlated with the severity of fibrosis. For fragments less than 2.5 cm or including less than 11 portal tracts, LSM could not predict significant fibrosis. Table I