Occult hepatitis B virus infection: a covert operation

Update on occult hepatitis B virus infection

The event of mutations in the surface antigen gene of hepatitis B virus (HBV) results in undetectable hepatitis B surface antigen with positive/negative anti-hepatitis B core (anti-HBc) antibody status in serum and this phenomenon is named occult hepatitis B infection (OBI). The presence of anti-HBc antibody in serum is an important key for OBI tracking, although about 20% of OBI cases are negative for anti-HBc antibody. The diagnosis of OBI is mainly based on polymerase chain reaction (PCR) and real-time PCR assays. However, real-time PCR is a more reliable method than PCR. OBI is a great issue for the public health problem and a challenge for the clinical entity worldwide. The persistence of OBI may lead to the development of cirrhosis and hepatocellular carcinoma. With regard to OBI complications, the screening of HBV DNA by the highly sensitive molecular means should be implemented for: (1) patients with a previous history of chronic or acute HBV infection; (2) patients co-infected with hepatitis C virus/human immunodeficiency virus; (3) patients undergoing chemotherapy or anti-CD20 therapy; (4) recipients of organ transplant; (5) blood donors; (6) organ transplant donors; (7) thalassemia and hemophilia patients; (8) health care workers; (9) patients with liver related disease (cryptogenic); (10) hemodialysis patients; (11) patients undergoing lamivudine or interferon therapy; and (12) children in time of HBV vaccination especially in highly endemic areas of HBV. Active HBV vaccination should be implemented for the close relatives of patients who are negative for OBI markers. Thus, the goal of this review is to evaluate the rate of OBI with a focus on status of high risk groups in different regions of the world.

Relationship between long non-coding RNAs and liver-related diseases and injuries

Long non-coding RNAs (lncRNAs) are a class of non-coding RNAs>200 bp in length. In recent years, it was discovered that lncRNAs play an important role in many physiological processes, such as transcription activation, transcriptional interference, X chromosome silencing, genomic imprinting and chromatin modification, transport and so on. More and more studies show alterations of lncRNA expression in primary liver cancer, hepatitis and other liver diseases. This paper reviews the relationship between long non-coding RNAs and liver-related diseases and injuries.

Clinical significance of miRNA changes in chronic liver diseases

MicroRNAs (miRNAs) are small molecules that regulate gene expression at the post-transcriptional level. MiRNAs could exhibit specific changes in many liver diseases, which reflects pathologic changes of hepatic tissue. To better understand the relationship between miRNAs and liver diseases, this review summarizes the roles of miRNAs in hepatitis, alcohol-induced liver injury, drug-induced liver injury and hepatocellular carcinoma. Investigation of miRNA changes in humans might not only help to elucidate the mechanism of chronic hepatitis B virus infection, but also provide new molecular markers for clinical diagnosis and evaluation of the curative effect of antiviral treatment. In addition, it might provide new ideas and methods for the diagnosis and treatment of alcoholic liver disease, drug-induced liver injury, fatty liver disease and hepatocellular carcinoma.

FibroScan vs hepatic histopathology for diagnosis of liver fibrosis in chronic hepatitis B patients with liver stagnation and spleen deficiency syndrome or damp and heat accumulation syndrome

AIM: To assess the application of FibroScan, a new non-invasive diagnostic technique, in the diagnosis of liver fibrosis in chronic hepatitis B (CHB) patients with liver stagnation and spleen deficiency syndrome or damp and heat accumulation syndrome.

METHODS: According to the clinical diagnosis of CHB and the TCM diagnostic criteria, we selected 180 CHB patients with damp and heat accumulation syndrome and 159 CHB patients with liver stagnation and spleen deficiency syndrome. The liver fibrosis stage was assessed by the liver stiffness measurement (LSM) evaluated by FibroScan, and the pathological diagnosis of liver fibrosis was determined using the METAVIR scoring system.

RESULTS: The total incidence rates of liver fibrosis exceeding F2 diagnosed by pathology in CHB patients with liver stagnation and spleen deficiency syndrome and those with damp and heat accumulation syndrome were 65.56% and 62.89%, with no significant difference (P > 0.05). The incidence rate of F4 liver fibrosis in CHB patients with damp and heat accumulation syndrome was 25.56%, which was significantly higher than that in patients with liver stagnation and spleen deficiency syndrome (16.35%) (χ² = 4.2748, P < 0.05). The incidence rate of F4 liver fibrosis determined by FibroScan in CHB patients with damp and heat accumulation syndrome was 15%, which was significantly higher than that in patients with liver stagnation and spleen deficiency syndrome (5.67%) (χ² = 7.7586, P < 0.01). Based on the "gold standard" diagnosis by hepatic histopathology, the total accuracy rates for diagnosis of liver fibrosis from ≥ F2 to F4 by FibroScan in CHB patients with liver stagnation and spleen deficiency syndrome and those with damp and heat accumulation syndrome were 75.42% and 66%, respectively, with no significant difference (P > 0.05). The accracy rate for diagnosis of liver fibrosis ≥ F2 by FibroScan in CHB patients with damp and heat accumulation syndrome was significantly higher than that in patients with liver stagnation and spleen deficiency syndrome (84.85% vs 63.04%, χ² = 4.5396, P < 0.05), while the accuracy rate for liver fibrosis ≥ F3 or F4 was similar between the two groups (P > 0.05).

CONCLUSION: There is a high incidence rate of liver fibrosis in CHB patients with liver stagnation and spleen deficiency syndrome or damp and heat accumulation syndrome. CHB patients with damp and heat accumulation syndrome are more susceptible to F4 liver fibrosis (cirrhosis). FibroScan can be used for non-invasive diagnosis of liver fibrosis in CHB patients with liver stagnation and spleen deficiency syndrome or damp and heat accumulation syndrome, especially for the initial stage of liver fibrosis in CHB patients with damp and heat accumulation syndrome.