Factors associated with hepatitis B virus (HBV) DNA breakthrough and the significance of YMDD variants without the presence of wild-type YMDD during prolonged lamivudine treatment are unknown. We studied the amino acid sequence of codon 552 (YMDD motif) and codon 528 by means of a line probe assay in 159 chronic HBV patients (median follow-up 29.6 months). Pretreatment HBV DNA levels and alanine transaminase (ALT) levels correlated inversely with the time to HBV DNA breakthrough with YMDD variants (r ‫؍‬ ؊0.46, P ‫؍‬ .001; r ‫؍‬ ؊0.45, P ‫؍‬ .001 respectively). Patients harboring YMDD variants 3 months before HBV DNA breakthroughs had higher HBV DNA breakthrough levels compared with those without YMDD variants 3 months before HBV DNA breakthroughs (18.9 ؋ 10 6 vs. 5.4 ؋ 10 6 copies/mL, P ‫؍‬ .007). Patients with HBV DNA breakthroughs had higher percentages of YMDD variants without the presence of wild-type YMDD compared with patients without HBV DNA breakthrough (25.6% vs. 9%, P ‫؍‬ .007 for single M552I variant; 20.9% vs. 8.1%, P ‫؍‬ .026 for single M552V variant; 30.2% vs. 9.9%, P ‫؍‬ .004 for M552I/M552V variants). Patients with HBV DNA levels of more than 10 3 copies/mL after 6 months of lamivudine therapy had a 63.2% chance of subsequently developing YMDD variants. HBeAg seroconversion occurred in 2 patients after the emergence of YMDD variants. Only one patient developed YMDD variant after HBeAg seroconversion. There was no increase in the rate of development of YMDD variants or L528M mutation in patients receiving lamivudine 25 mg daily or famciclovir 500 mg 3 times a day before being given lamivudine 100 mg daily. (HEPATOLOGY 2001;34:785-791.)Hepatitis B virus (HBV) infection is a major international health problem leading to around 1.2 million deaths per year world-wide. 1 Because of its profound suppression of HBV replication resulting in significant histologic improvement, lamivudine is commonly used as a treatment of chronic HBV infection. [2][3][4] However, in 14% to 32% of patients, a 1-year treatment regimen of lamivudine 100 mg daily is associated with mutation of the tyrosine, methionine, aspartate, aspartate (YMDD) motif in the C domain of the HBV DNA polymerase gene, corresponding to the amino acid codon 552 of the HBV. 2,3 The number of patients with YMDD mutation is higher with prolonged use of lamivudine. 5 For the YMDD variants, the methionine is substituted with either isoleucine (I), designated M552I or valine (V), giving rise to M552V. There may be another concomitant mutation occurring at the B domain of the HBV polymerase gene with the leucine (L) at amino acid codon 528 substituted by methionine (L528M). This mutation has been described for patients on famciclovir. 6,7 With lamivudine treatment, L528M is usually associated with M552V though M552I/L528M has also been reported. 8 Both in vitro and in vivo studies show that YMDD variants are less replication-competent compared with the wild-type, are associated with lower HBV DNA levels compared with pretreatment HBV DNA levels, and can...

Background Hepatitis B virus-related acute liver failure (HBV-ALF) may occur following acute HBV infection (AHBV-ALF) or during an exacerbation of chronic HBV infection (CHBV-ALF). Clinical differentiation of the two is often difficult if a prior history of hepatitis B is not available. Quantitative measurements of anti-hepatitis B core immunoglobulin M (IgM anti-HBc) titers and of HBV viral loads (VLs) might allow separation of acute from chronic HBV-ALF. Methods Of 1602 patients with ALF, 60 met clinical criteria for AHBV-ALF and 27 for CHBV-ALF. Sera were available on 47 and 23 patients, respectively. A quantitative immunoassay was used to determine IgM anti-HBc levels, and real-time polymerase chain reaction (rtPCR) to determine HBV VLs. Results AHBV-ALFs had much higher IgM anti-HBc titers than CHBV-ALFs, (signal to noise (S/N) ratio median 88.5, range 0–1,120, vs. 1.3, 0–750, p<0.001); a cut point for S/N ratio of 5.0 correctly identified 44/46 (96%) AHBV-ALFs and 16/23 (70%) CHBV-ALFs; the area under the receiver operator characteristic curve was 0.86, p<0.001. AHBV-ALF median admission VL was 3.9 (0–8.1) log10 IU/mL, vs. 5.2 (2.0–8.7) log10 IU/mL for CHBV-ALF, p<0.025. Twenty percent (12/60) of the AHBV-ALF group had no hepatitis B surface antigen (HBsAg) detectable on admission to study, while no CHBV-ALF patients experienced HBsAg clearance. Rates of transplant-free survival were 33% (20/60) for AHBV-ALF vs. 11% (3/27) for CHBV-ALF, p=0.030. Conclusions AHBV-ALF and CHBV-ALF differ markedly in IgM anti-HBc titers, in HBV VLs and in prognosis, suggesting that the two forms are indeed different entities that might each have a unique pathogenesis.

Background Osteopontin (OPN) is a novel phosphoglycoprotein expressed in Kupffer cells that plays a pivotal role in activating natural killer cells, neutrophils and macrophages. Measuring plasma OPN levels in patients with acute liver failure (ALF) might provide insights into OPN function in the setting of massive hepatocyte injury. Methods OPN levels were measured using a Quantikine® ELISA assay on plasma from 105 consecutive ALF patients enrolled by the US Acute Liver Failure Study Group, as well as controls including 40 with rheumatoid arthritis (RA) and 35 healthy subjects both before, and 1 and 3 days after undergoing spine fusion (SF) surgery as a model for acute inflammation. Results Median plasma OPN levels across all etiologies of ALF patients were elevated 10- to 30-fold: overall median 1055 ng/mL; range: 33 – 19127), when compared to healthy controls (median in pre-SF patients: 41 ng/mL; range 2.6 – 86.4). RA and SF post op patients had elevated OPN levels (37 ng/mL and 198 ng/mL respectively), well below those of the ALF patients. Median OPN levels were highest in acetaminophen (3603 ng/mL) and ischemia-related ALF (4102 ng/mL) as opposed to viral hepatitis (706 ng/mL), drug-induced liver injury (353 ng/mL) or autoimmune hepatitis (436 ng/mL), correlating with the degree of hepatocellular damage, as reflected by aminotransferase values (R value: 0.47 for AST, p < 0.001). Conclusions OPN levels appeared to correlate with degree of liver necrosis in ALF. Very high levels were associated with hyperacute injury and good outcomes. Whether OPN exerts a protective effect in limiting disease progression in this setting remains uncertain.

Commercially available rapid strip assays (RSAs) for hepatitis B surface antigen (HBsAg) are used for most routine clinical testing in sub-Saharan Africa. This study evaluated the validity of RSA and a more sophisticated enzyme immunoassay (EIA) with confirmation by nucleic acid testing (NAT) in hospitalized patients in Uganda. Sera from 380 consecutive patients collected and tested for HBsAg and anti-HIV in Kampala, Uganda by RSA were sent frozen to Dallas for EIA including HBsAg, total anti-hepatitis B core, hepatitis B e antigen, and anti-HIV. NAT was performed on all HBsAg-positives and on a random sample of 102 patients that were HBsAg-negative by both assays. Overall, 31 (8%) were HBsAg positive by RSA while 50 (13%) were HBsAg-positive by EIA; 26 were concordant between the two assays. Of 55 HBsAg-positive patients, nearly all showed detectable serum hepatitis B virus (HBV) DNA by bDNA (46) or PCR (4) assay. The 26 patients who were HBsAg positive by both EIA and RSA had significantly higher median serum HBV DNA levels than the 24 patients who were HBsAg positive by EIA alone. An additional 12/102 (12%) HBsAg negative patients had very low serum HBV DNA levels by NAT. Several differences in expected results of serologic testing were observed in this large series of African patients. RSA HBsAg testing is less sensitive than EIA; even EIA failed to detect all HBV DNA positive sera. A more complex testing protocol than RSA alone will be needed in Africa to improve patient care.

Respiratory dendritic cells (DC) play a pivotal role in the initiation of adaptive immune responses to influenza virus. To do this, respiratory DCs must ferry viral antigen from the lung to the draining lymph node without becoming infected and perishing en route. We show that respiratory DCs up-regulate the expression of the antiviral molecule, interferon-induced transmembrane protein 3 (IFITM3) in response to influenza virus infection, in a manner dependent on type I interferon signaling and the transcription factors IRF7 and IRF3. Failure of respiratory DCs to up-regulate IFITM3 following influenza virus infection resulted in impaired trafficking to the draining LN and consequently in impaired priming of an influenza-specific CD8+ T cell response. The impaired trafficking of IFITM3-deficient DC correlated with an increased susceptibility of these DC to influenza virus infection. This work shows that the expression of IFITM3 protects respiratory DCs from influenza virus infection, permitting migration from lung to LN and optimal priming of a virus specific T-cell response.

Tirofiban bolus over 3 min followed by maintenance infusion appears to be a safe and efficient prophylactic protocol for the endovascular treatment of ruptured intracranial aneurysms and may be an alternative to intraoperative oral antiplatelet therapy, especially in the case of stent-assisted embolization.

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