HBV Diagnosis Research Articles

Prevalence and characteristics of hepatitis B and C virus infections in treatment-naïve HIV-infected patients

In HIV-infected treatment-naïve patients, we analyzed risk factors for either chronic hepatitis B (HBV) infection, occult HBV infection (OHBV) or a positive hepatitis C (HCV) serostatus. A total of 918 patients of the RESINA-cohort in Germany were included in this study. Before initiating antiretroviral therapy, clinical parameters were collected and blood samples were analyzed for antibodies against HIV, HBV and HCV, HBs antigen and viral nucleic acids for HIV and HBV. Present or past HBV infection (i.e. HBsAg and/or anti-HBc) was found in 43.4% of patients. HBsAg was detected in 4.5% (41/918) and HBV DNA in 6.1% (34/554), resulting in OHBV infection in 2.9% (16/554) of patients. OHBV infection could not be ruled out by the presence of anti-HBs (50.1%) or the absence of all HBV seromarkers (25%). A HCV-positive serostatus was associated with the IVDU transmission route, non-African ethnicity, elevated liver parameters (ASL or GGT) and low HIV viral load. Replicative HBV infection and HCV-positive serostatus both correlated with HIV resistance mutations (P=0.001 and P=0.028). HBV and HCV infection are frequent co-infections in HIV treatment-naive patients. These co-infections influence viral evolution, clinical parameters and serological markers. Consequently, HIV patients should routinely be tested for HBV and HCV infection before initiating HIV treatment. OHBV infection constituted almost half of all HBV infections with detectable HBV DNA. Due to a lack of risk factors indicating OHBV infection, HBV diagnosis should not only include serological markers but also the detection of HBV DNA.

Occult hepatitis B in the genotype H‐infected Nahuas and Huichol native Mexican population

Mexico is considered to be a low endemic country for HBV infection. However, a high anti-HBc against a low hepatitis B surface antigen (HBsAg) seroprevalence is the reported characteristic of native Mexicans. HBV diagnosis and genotype distribution was examined in native populations (Nahuas and Huichol, n = 306), and compared to a non-native population (Mestizos, n = 17). Overall, 6% of the natives were positive for HBsAg and 33% had detectable anti-HBc. HBsAg prevalence was lower in Nahuas compared to Huichols (1.4% vs. 9.4%, P < 0.002). Occult hepatitis B was detected in 14.2% (41/289) of natives, who either tested positive (5.88%, 17/289 HBsAg-negative) or negative for anti-HBc marker (8%, 24/289 HBsAg-negative). Age-adjusted anti-HBc seroprevalence and HBsAg quantitation revealed a sub-optimal sensitivity of conventional immunoassays. Nahuas had HBV/H and Huichol had HBV/A as the predominant genotypes followed by genotypes D, C, B, A, and D, G and H, respectively. A less variable HBV/H was characteristic in Mestizos, compared to a much variable HBV/H identified among the Nahuas. In conclusion, these findings indicate a high HBV endemicity among native Mexican groups where occult B infection is common. The different distribution of HBV genotypes among natives suggests multiple reservoirs of HBV from which these genotypes spread into the local communities. High anti-HBc seroprevalence against a low HBsAg prevalence rate may be due to the limited sensitivity of the immunoassays for the detection of HBsAg that are available in Mexico and/or unknown immunogenetic characteristics of native Mexicans.

Application of PCR‐LDR‐nucleic acid detection strip in detection of YMDD mutation in hepatitis B patients treated with lamivudine

Chronic hepatitis B virus (CHBV) infection causes cirrhosis and hepatocellular carcinoma. Lamivudine (LAM) has been successfully used to treat CHBV infections but prolonged use leads to the emergence of drug-resistant variants. This is primarily linked to a mutation in the tyrosine-methionine-aspartate-aspartate (YMDD) motif of the HBV polymerase gene at position 204. Rapid diagnosis of drug-resistant HBV is necessary for a prompt treatment response. Common diagnostic methods such as sequencing and restriction fragment length polymorphism (RFLP) analysis lack sensitivity and require significant processing. The aim of this study was to demonstrate the usefulness of a novel diagnostic method that combines polymerase chain reaction (PCR), ligase detection reaction (LDR) and a nucleic acid detection strip (NADS) in detecting site-specific mutations related to HBV LAM resistance. We compared this method (PLNA) to direct sequencing and RFLP analysis in 50 clinical samples from HBV infected patients. There was 90% concordance between all three results. PLNA detected more samples containing mutant variants than both sequencing and RFLP analysis and was more sensitive in detecting mixed variant populations. Plasmid standards indicated that the sensitivity of PLNA is at or below 3,000 copies per ml and that it can detect a minor variant at 5% of the total viral population. This warrants its further development and suggests that the PLNA method could be a useful tool in detecting LAM resistance.

Detection of antibodies to hepatitis B core antigen using the Abbott ARCHITECT ® anti-HBc assay: Analysis of borderline reactive sera

Routine use of the automated chemiluminescent microparticle immunoassay Abbott ARCHITECT ® anti-HBc for diagnosis of hepatitis B is limited in case of borderline reactive sera with low signal close to the cut-off index. In order to determine the significance of anti-HBc detection when borderline reactivity occurs using the ARCHITECT ® anti-HBc assay, a comparative study was designed. 3540 serum samples collected over a 2-month period in the hospital of Nice were examined for markers of HBV infection (HBsAg, anti-HBs and anti-HBc). One hundred seven samples with sufficient volume and with borderline reactivity by the ARCHITECT ® assay were tested by two other anti-HBc assays, a microparticle enzyme immunoassay (MEIA, AxSYM ® Core™, Abbott Laboratories, IL, USA) and an enzyme linked fluorescent assay (ELFA, VIDAS ® Anti-HBc Total II, bioMérieux, Lyon, France). Only 46 samples were confirmed by the AxSYM ® and the VIDAS ® assays. Additional serological information linked to patient history showed that the remaining samples (61) were false positives (11), had low titer of anti-HBc antibodies (13), or were inconclusive (37). This comparative study highlighted the existence of a grey zone around the cut-off index. Confirmative results through a different immunoassay are needed to confirm the diagnosis of HBV on borderline reactive sera using the ARCHITECT ® anti-HBc assay.

High throughput detection of drug-resistance gene mutations in HBV using MALDI-TOF mass spectrometry

To develop a high-throughput clinical method on drug-resistance gene mutations of HBV using MALDI-TOF-MS. Using MassArray Assay Design software designed the iPLEX primers and followed the iPLEX instruction for amplification, SAP reaction, primer extenction, desalination, dispensing, MALDI-TOF-MS screening and data analysis of the gene mutation locus. 138 serum samples of chronic HBV patients with single drug-resistance or multiple drug-resistance on Lamivudin, adefovi, Entecavir were detected. The HBV gene mutation platform was successfully developed and applied on the high-throughput dectection of clinical serum samples. It was also a high throughput assay which could be used to detect for more than 138 samples once. The MALDI-TOF-MS technology and the DNA sequencing simultaneously examine 33 samples, in which result of 10 sample is inconsistent, the including 2 samples by MALDI-TOF-MS technology has not tested, 1 sample has 2 inconsistent mutations. Detection of HBV gene mutations using MALDI-TOF-MS is highly-sensitive, highly-accurate, high-throughput, fast achieved and suitable to use in the diagnosis and monitoring of HBV.

Strategien zur Prävention des hepatozellulären Karzinoms bei der Hepatitis-Virus-Infektion

Liver cirrhosis induced by HBV and HCV infections is the main risk factor for the development of hepatocellular carcinoma (HCC). Therefore, prevention of chronic infection with hepatitis viruses and prevention of the development of cirrhosis are essential for the primary prevention of HCC. A consequent vaccination program for HBV is suitable to reduce the rate of infections and the HCC-associated mortality. Since no vaccine is available for HCV, the reduction of risky behaviour and the improvement of hygiene standards are the mainstays for prevention of HCV. An efficient antiviral therapy aimed at the durable suppression of the viral load reduces the risk of progression to cirrhosis and development of HCC in precirrhotic stages of chronic HBV or HCV infections. In cirrhotic patients, the risk of developing HCC remains elevated even if a sustained virological response is achieved, thus requiring further screening with the intention of the early detection of HCC. It is too early to judge whether virological nonresponders profit from continued antiviral therapy. Therefore, the early diagnosis of chronic HBV or HCV infection is the single most important factor for the prevention of HCC. Secondary prevention after surgical resection or local ablative therapy may reduce the frequency of late recurrence. Liver transplantation is today the most effective measure of secondary prevention for selected patients with HCC. Due to its antiproliferative effects, the immunosuppressive drug sirolimus may play a role for secondary prevention of HCC following transplantation.

Hepatitis B and C Viruses in Infants and Young Children

Advances during the past 20 years have led to a better understanding of the prevention, diagnosis, and treatment of acute and chronic hepatitis B (HBV) and hepatitis C (HCV) infections in the pediatric population. Universal vaccination and prenatal testing for HBV have decreased the incidence rate of acute HBV infections from more than 3/100,000 to 0.34/100,000 in all children. Diagnosis of chronic HBV is confirmed with positive serologic testing on two occasions at least 6 months apart. Current approved therapies with interferon alpha and lamivudine for children with chronic HBV infection have shown some efficacy, but results have been variable. In contrast, the lack of an effective HCV vaccine and the risk of mother-to-child transmission may increase the number of children with vertically acquired HCV that ultimately go on to develop liver fibrosis or cirrhosis. Diagnosis of HCV in the neonate should be postponed until after the child reaches 1 year of age because infants may have transient viremia. Treatment for HCV infected children has not been studied extensively. Peginterferon alpha-2a and Ribavirin are not currently approved for pediatric use; however, recent studies in children have shown potential benefit. More effective and less toxic therapies for young patients with HBV and HCV are needed, as are methods to interrupt perinatal transmission of HBV and HCV.

Occupational blood-borne diseases in surgery

Background Human immunodeficiency virus (HIV), hepatitis B (HBV), and hepatitis C (HCV) infections are transmitted by blood exposure. Surgeons have been concerned about the risks of blood exposure in the operating room as a potential source of occupational infections from these viruses. The actual risk and frequency of operating room transmission remains poorly understood by many surgeons. Methods The pertinent recent literature on the pathophysiology, diagnosis, prevention, and treatment of HIV, HBV and HCV were reviewed to address the current understanding of these viruses as occupational risks to surgeons. Results HIV transmission to surgeons has not been documented in the United States by the Centers for Disease Control. HIV transmission from a surgeon to a patient in the environment of the operating room, as well as transmission from an HIV-infected surgeon to a patient, has not been documented. HBV infection of surgeons has declined with the general acceptance of the HBV vaccine. HCV infection remains a real risk for transmission in the operating room, given that no vaccine is currently available and that the overall number of chronically infected patients remains quite high. Conclusion The risk of occupational infection from known viral pathogens for surgeons is low, but it is not zero. Effective barriors, modified patterns of behavior, and prompt responses to blood exposure events are the best methods for prevention.

Visual gene diagnosis of HBV and HCV based on nanoparticle probe amplification and silver staining enhancement.

A visual gene-detecting technique using nanoparticle-supported gene probes is described. With the aid of gold nanoparticle-supported 3'-end-mercapto-derivatized oligonucleotide serving as detection probe, and 5'-end -amino-derivatized oligonucleotide immobilized on glass surface acting as capturing probe, target DNA was detected visually by sandwich hybridization based on highly sensitive "nano-amplification" and silver staining. Different genotypes of Hepatitis B and C viruses in the serum samples from infected patients were detected using home-made HBV, HCV, and HBV/HCV gene chips by the gold/silver nanoparticle staining amplification method. The present visual gene-detecting technique may avoid limitations with the reported methods, for its high sensitivity, good specificity, simplicity, speed, and cheapness. This technique has potential applications in many fields, especially in multi-gene detection gene chips coupled with the detection will find applications in clinic. Additionally, resonance Rayleigh light scattering (RLS) spectroscopy is used, for the first time, to judge and monitor the immobilization of gene probes on gold nanoparticle surfaces.

SHOULD LIVER TRANSPLANTATION BE PERFORMED FOR PATIENTS WITH HEPATITIS B?

Because of the almost universal recurrence of hepatitis B surface antigenemia (HBsAg) after liver transplantation, some centers have questioned whether these patients are appropriate allograft candidates. Since January 1984, 51 patients with hepatitis B (HBV) underwent OLT at our center. No therapy was given to prevent reinfection. Three patients underwent retransplantation. The indications for transplant included fulminant HBV (13 patients), chronic HBV (33 patients), and hepatocellular carcinoma (HCCA) in addition to HBV (5 patients). Incidental HCCA was found in 2 of the 33 patients thought to have only chronic HBV. Actuarial survival for the entire group was 57% at 1 year and 54% at 3 years. Of the 23 patients who died, only 4 deaths were attributable to recurrent HBV liver disease. Four patients survived less than 4 days due to primary graft nonfunction. Ten patients died in the first 3 months from sepsis. Although all patients who died beyond 30 days had recurrent HBsAg, only 4 deaths were attributable to recurrent HBV. The remaining 5 deaths were caused by portal vein thrombosis, bile leak, lymphoma, pancreatitis, and sepsis occurring at 15 months. Excluding the 4 patients who died from primary graft nonfunction, actuarial survival was 63% at 1 year and 60% at 3 years. Of the 28 survivors, 24 are HBsAg positive; however, only 5 have recurrent HBV liver disease. Multiple factors were evaluated to determine their influence on survival; i.e., HBV serology, United Network for Organ Sharing status, fulminant versus chronic HBV, incidence of rejection, immunosuppression, transfusion requirements, and presence of HCCA. Of these, only the presence of HCCA adversely affected outcome. Of the 7 patients with HCCA and HBV, 6 patients died within the first 6 months and 1 patient has recurrent HBV liver disease at 25 months. Actuarial survival excluding those patients with HCCA was 64% at 1 year and 61% at 3 years. Based on our results, patients with HBV and associated HCCA have a poorer prognosis and should probably be excluded from transplantation. Although the survival for patients with HBV undergoing liver transplantation is inferior to that expected in patients with some other diagnoses, long-term survival can be achieved in a majority of these patients despite recurrence of HBsAg. We believe that appropriately selected patients with a diagnosis of HBV alone should continue to be candidates for liver allografts.