Occult hepatitis C virus infection: what does it mean?

Occult hepatitis C virus infection (OCI) is a recently identified entity of which the existence became evident when nucleic acid amplification assays of enhanced sensitivity were introduced for the detection of hepatitis C virus (HCV) genome and its replication. This form of HCV infection has been found to persist in the presence of antibodies against HCV and normal levels of liver enzymes for years after spontaneous or antiviral therapy‐induced resolution of hepatitis C and, therefore, can be termed as secondary OCI. HCV RNA in OCI circulate at fluctuating levels normally not exceeding 200 genome copies per millilitre of serum or plasma, while low levels of virus genome and its replicative intermediate RNA‐negative strand are detectable in the liver and, importantly, immune cells, which provide an opportunity to detect active virus replication without the need for acquiring a liver biopsy. In addition to secondary OCI, a form of OCI accompanied by persistently moderately elevated serum liver enzymes in the absence of antibodies to HCV, which can be termed as cryptogenic OCI, has also been described. The current understanding of the nature and characteristics of OCI, methods and pitfalls of its detection, as well as the documented and expected pathological consequences of OCI will be summarized in this review.     

Is hepatitis C virus infection of dendritic cells a mechanism facilitating viral persistence?

More than 170 million people worldwide are chronically infected with hepatitis C virus (HCV), which is a major cause of chronic hepatitis, cirrhosis, and hepatocellular carcinoma. Impaired T-cell reactivity to HCV, a hallmark of inefficient adaptive immunity, is believed to be responsible for the high propensity of HCV to cause chronic infection. Dendritic cells are the most potent antigen-presenting cells and many viruses affect various dendritic cell functions. Data suggest that such changes induced by HCV may have an important role in viral persistence. HCV has been shown to bind to dendritic cells, although viral replication within these cells occurs at a very low level. Dendritic cells from people with chronic HCV infection are impaired in their capacity to stimulate T cells. This impairment may be a consequence of changes in the expression of major histocompatibility complex and costimulatory molecules on its surface, as well as in the production of cytokines such as interleukin 12. In addition, hepatic dendritic cells may be affected by the tolerogenic microenvironment of the liver, possibly generating dendritic cells that promote regulatory T cells, which suppress the cellular immune response mounted against HCV.     

Does Fasciola hepatica infection modify the response of acute hepatitis C virus infection to IFN-α treatment?

Immunologic response to acute hepatitis C is mainly a Th1 response, whereas fasciolopsiasis is associated with a diverse T-cell response. Interferon-alpha has immunomodulatory effects and enhances Th1 immune response. Fasciola infection could theoretically interfere with the Th1 immune response, even when acquired after an initial response to interferon-alpha treatment for acute hepatitis C virus (HCV) infection. We report here the case of a male patient who acquired Fasciola hepatica infection after an initial response to IFN-alpha therapy with a favorable outcome     

The course and therapy of acute hepatitis C viral infection. Is a prevention of its becoming chronic possible?

Due to the large number of patients chronically infected with hepatitis C virus and not responding to combination therapy with interferon-alfa 2 and ribavirin new therapeutic regimens are required. Early treatment of the viral infection might improve the response, as seen in treatment of HIV infection, thereby preventing progression to chronicity. The article reviews the natural course of an acute HCV infection after different modes of transmission like i.v.-drug abuse, transfusion, needle stick injury and blood products. As there are no good animal models for HCV infection, models of an acute infection with other noncytopathic viruses might improve our understanding of the mechanisms of viral clearance. Results from an acute infection of mice with the lymphocytic chorionmeningitis virus are demonstrating the development of a T-cell tolerance by anergy or deletion of virus specific T-cells as possible mechanisms for the failure of the immune system to clear the virus. These findings are compared to the results of CD4+ and CD8+ T-cell responses in patients with acute HCV infection. Several clinical trials have demonstrated a benefit of an early treatment of HCV infection. Although the natural course of acute HCV is changing during the last few years, even recent trials indicate that progression to chronicity might be prevented by early therapy. The studies show that therapy could be improved by daily dosing, higher single doses of interferon compared and prolongation of therapy up to six month. As most patients with acute HCV infection are rather seen in an outpatient practise than in hospitals cases of acute infections should be collected and treatment protocols be standardized to confirm these results in prospective trials. First results in 21 patients show that viral clearance under therapy was achievable in all of the patients.     

Unexpected long‐lasting anti‐HEV IgM positivity: Is HEV antigen a better serological marker for hepatitis E infection diagnosis?

Hepatitis E virus (HEV) is the leading cause of acute hepatitis worldwide. The minimum criterion for diagnosis of acute infection is detection of anti‐HEV antibodies, although there are scant data on IgM duration. Our aim was to assess the persistence of HEV markers after acute self‐limited hepatitis E. HEV serological tests (IgM by Mikrogen and Wantai and HEV‐Ag) and HEV RNA were carried out in two cohorts: (a) patients with prior acute hepatitis E (ALT >10 x ULN plus positive IgM ± HEV RNA) currently self‐limited and (b) 50 blood donors with positive HEV RNA. Among 25 cases of prior acute hepatitis E, after a median follow‐up of 34 months, all presented undetectable HEV RNA. However, anti‐HEV IgM remained detectable in 14 (56%) by Mikrogen, 6 (24%) by Wantai and none for HEV‐Ag. Anti‐HEV IgM tested positive in 80%‐100% within the second year and 17%‐42% over 3 years later, by Wantai and Mikrogen, respectively. Among HEV RNA‐positive donors, 12 (25%) tested positive for either IgM by Mikrogen or Wantai, 9 (18%) for both and 18 (36%) for HEV‐Ag. HEV‐Ag positivity was more likely as HEV RNA was higher (14% if <2.2 log IU/mL; 64% if RNA ≥ 3.7). Overall, HEV‐Ag performed best, with a positive predictive value of 100% and diagnostic accuracy of 57%. Anti‐HEV IgM exhibited unexpectedly long persistence after a self‐limited acute hepatitis E. HEV‐Ag had the best performance and could be especially useful in settings where HEV RNA is not available.     

Is it possible to detect ulcerative colitis‐related respiratory syndrome early?

OBJECTIVE: Obstructive airway disease, bronchiectasis, non-specific parenchymal infiltration and bronchiolitis obliterans organizing pneumonia are seen occasionally in patients with inflammatory bowel disease. In the present study, we evaluated ulcerative colitis (UC) patients for latent pulmonary involvement. METHODS: Fifteen patients (nine females, six males, mean age 44 years) were admitted into the study. All patients were free of respiratory symptoms. Ulcerative colitis was active in nine patients and all patients were using anti-inflammatory treatment. Pulmonary function tests (PFT), high resolution computed tomography of thorax (HRCT) and bronchoscopy with bronchoalveolar lavage (BAL) and transbronchial biopsy (TBLB) were carried out in all subjects. RESULTS: Mild airways obstruction was found in 1 of 13 patients. High resolution CT was abnormal in 4 of 15 patients. Ground glass appearance suggestive of an interstitial lung disease was present in three patients. Radiolucency and pneumocysts were present in the fourth patient suggesting obstructive small airway disease. High resolution CT findings correlated with disease activity (P < 0.05). Fiberoptic bronchoscopy was performed in 10 patients. A mixed type alveolitis was detected in BAL fluid in five patients. In eight patients, TBLB showed alveolar septal thickening by connective tissue, lymphocytic accumulation in the septal area and minimal septal fibrosis, suggesting subclinical pulmonary parenchymal involvement linked to UC. CONCLUSIONS: Our data suggest that latent interstitial pulmonary involvement may occur during the course of UC, despite an absence of symptoms of lung disease.     

Reactivation of resolved hepatitis B virus infection after immunosuppression: Is it time to adopt pre-emptive therapy?

New therapeutic options like monoclonal antibodies (anti-CD20/rituximab) and hematopoietic stem cell transplantation (HSCT) have increased both the effectiveness of therapies and the risk for reactivation of Hepatitis B virus (HBV). We describe two cases with serological evidence of resolved HBV infection (hepatitis B surface antigen (HBsAg) negative/antibody to hepatitis B core antigen (anti-HBc) and antibody to hepatitis B surface antigen (anti-HBs) positive), who developed reverse seroconversion (clearance of HBsAb/appearance of HBsAg) with active HBV infection after treatment with combination of conventional chemotherapy, rituximab and autologous HSCT for hematological malignancies. Review of the literature highlights the increasing incidence of HBV reactivation in patients with resolved infection and raises concerns as to whether current guidelines for pre-chemotherapy screening with sensitive HBV-DNA assays and serial monitoring for anti-HBs titres should be implemented also for patients with resolved infection. Future studies should aim at clarifying the cost-benefit from administration of nucleoside analogues in these patients.     

Is it possible to cure childhood acute myeloid leukaemia without significant cardiotoxicity?

Since cardiotoxicity is a life threatening late effect, a reduction of cardiotoxicity in the treatment of acute myeloid leukaemia (AML) is essential. This review is a compilation of the current knowledge about cardiotoxicity after AML treatment and of how future directions in treatment may affect its incidence. A total of six studies concerning AML and cardiotoxicity were identified. The incidence of late subclinical cardiotoxicity varied between 1·3 and 15·3%, and late clinical cardiotoxicity varied between 1·3 and 9·3%. Cumulative dose of anthracyclines (ACs) and history of relapse were the most common risk factors identified. No conclusions could be drawn about new, potentially less toxic ACs. Differences in treatment data and variations in study populations made comparisons uncertain. The echocardiographic techniques used in the majority of the studies are inferior to more modern echocardiographic methods. This decreases reproducibility and may increase the risk of overestimation of cardiotoxicity. In summary, AML cannot be cured today without ACs. However, some ACs may cause less cardiotoxicity than others. Furthermore there is currently no consensus on equipotent doses of ACs and risk factors for cardiotoxicity. Further research including randomized trials is needed to evaluate whether or not the potentially less cardiotoxic agents fulfil their promise.     

Is it possible to stop nucleos(t)ide analogue treatment in chronic hepatitis B patients?

Chronic hepatitis B(CHB) remains a challenging global health problem, with nearly one million related deaths per year. Nucleos(t)ide analogue(NA) treatment suppresses viral replication but does not provide complete cure of the hepatitis B virus(HBV) infection. The accepted endpoint for therapy is the loss of hepatitis B surface antigen(HBs Ag), but this is hardly ever achieved. Therefore, indefinite treatment is usually required. Many different studies have evaluated NA therapy discontinuation after several years of NA treatment and before HBs Ag loss. The results have indicated that the majority of patients can remain off therapy, with some even reaching HBs Ag seroconversion. Fortunately, this strategy has proved to be safe, but it is essential to consider the risk of liver damage and other comorbidities and to ensure aclose follow-up of the candidates before considering this strategy. Unanswered questions remain, namely in which patients could this strategy be effective and what is the optimal time point at which to perform it. To solve this enigma, we should keep in mind that the outcome will ultimately depend on the equilibrium between HBV and the host's immune system. Viral parameters that have been described as good predictors of response in HBe Ag(+) cases, have proven useless in HBe Ag(-) ones. Since antiviral immunity plays an essential role in the control of HBV infection, we sought to review and explain potential immunological biomarkers to predict safe NA discontinuation in both groups.     

Is psychosocial and cognitive dysfunction misattributed to the virus in hepatitis C infection? Select psychosocial contributors identified

Chronic hepatitis C is associated with health‐related quality of life and cognitive impairments, even in mild disease. Recent evidence demonstrating hepatitis C virus (HCV) neurotropism has strengthened a neuropathophysiological hypothesis. However, sample heterogeneity confounds study outcomes. A uniquely homogeneous cohort of Irish women, following an iatrogenic HCV outbreak, offers a rare opportunity to control for HCV chronicity and the virus’ purported impact on quality of life and cognition. A multi site, three‐group, cross‐sectional design was employed. Noncirrhotic, iatrogenically infected women, developing either acute or chronic infection, were recruited from prospective tertiary‐care liver clinics and the community. Well‐matched healthy controls were also recruited. All participants completed a psychosocial survey and were invited to undergo a comprehensive neuropsychological test battery. Significantly distressed psychosocial symptom profiles were observed in those with an iatrogenic HCV exposure history, which was independent of viral chronicity. Chronic and cleared HCV cohorts were not differentiated from each other. Two distinct subgroups, demarcated along ‘impaired’ vs ‘nonimpaired’ quality‐of‐life reports, were clearly identified and logistic regression analysis identified depressed mood and cognitive fatigue, rather than viral status, as statistically significant predictors of group membership. Compared with matched controls, significant cognitive impairments were not observed in either HCV cohort. Our findings provide strong evidence of nonviral factors accounting for quality of life impairment in chronic HCV and they also appear to question existing reports of cognitive dysfunction in mild disease. Depressed mood and cognitive fatigue appear to be critical psychosocial mediators of reduced quality‐of‐life and we hypothesize that metabolite abnormalities reported in HCV samples may also be confounded by these factors, given the associated literature.     

What is (cost) effective in patients with chronic hepatitis C virus infection?

Hepatitis C virus (HCV) infection often progresses to chronic hepatitis, cirrhosis, and possibly hepatocellular carcinoma. Chronic hepatitis C infection is a leading cause of chronic liver disease and the most common indication for liver transplantation. Combination therapy of interferon alpha and ribavirin is currently the standard regimen for chronic hepatitis C. This combination can achieve viral clearance in approximately 40% of patients, and improve histology and prognosis. The most cost-effective approach to guide duration of combination therapy is HCV genotyping. Cost effectiveness cannot be improved further by taking other well-defined predictive factors for sustained virological response into account. Recent insights into HCV kinetics and the correlation between initial viral decline and sustained virological response will allow us to optimize and individually tailor antiviral treatment Individualized treatment according to the initial viral decline, together with further improvements in drugs (e.g. by long-acting pegylated interferons), will have new impact on antiviral efficacy and cost effectiveness.     

Is it necessary to administer anti‐D to prevent RhD immunization after the transfusion of RhD‐positive platelet concentrates?

Serology for the presence of anti-D after RhD-incompatible platelet transfusions was performed in 24 RhD-negative patients with haematological disease and 59 RhD-negative patients with non-haematological disease. None of the patients were given prophylaxis with anti-D to prevent RhD immunization. Eight out of 59 (13.5%) non-haematology patients developed detectable anti-D, whereas 0 out of 24 (0%) of the haematology patients formed anti-D (P = 0.06). The risk of alloimmunization after RhD-incompatible platelet transfusions using platelet concentrates prepared by modern technical methods appears to be small in patients with haematological disease, but is significant in non-immunocompromised patients.